University of Montana
ScholarWorks at University of Montana
Theses, Dissertations, Professional Papers
Graduate School
1973
The ecology of polar bears on North Twin Island
Northwest Territories
Brian Murray Knudsen
The University of Montana
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Recommended Citation
Knudsen, Brian Murray, "The ecology of polar bears on North Twin Island Northwest Territories" (1973). Theses, Dissertations,
Professional Papers. Paper 6412.
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T H E E C O L O G Y O F P O L A R B E A R S O N N O R T H T W IN IS L A N D ,
NORTHW EST
T E R R IT O R IE S
By
B r ia n M . Knuds en
B . Sc. (H ons. ),
U n iv e r s ity of M a n ito b a , 1969
P re s e n te d in p a r t ia l f u lf illm e n t o f th e r e q u ir e m e n ts f o r th e d e g re e of
M a s t e r of S cien c e
U N IV E R S IT Y
OF
M ONTANA
1973
A p p ro v e d by:
School
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ACKNOW LEDGM ENTS
I a m p a r t ic u la r ly In d eb ted to D r . John J. C ra ig h e a d w ho
ta u g h t m e , d u rin g th e y e a r s w h en I w as h is s tu d e n t, m u ch m o r e th an
is in d ic a te d in th is th e s is .
M y thanks a ls o go to th e o th e r m e m b e r s of
m y a d v is o r y c o m m itte e , D r s . L . M e tz g a r , D . J e n n i, K . F e v o ld , and
e s p e c ia lly D r . B . W . O 'G a r a , f o r t h e ir e n c o u ra g e m e n t, a s s is ta n c e ,
and sound a d v ic e .
D r . C h a r le s J o n k e l, o f th e C a n a d ia n W ild lif e S e r v ic e , w as m y
g u a rd ia n a n g e l d u rin g th e t e r m of th is s tu d y and f o r s e v e r a l y e a rs
e a r lie r .
F o r h is h e lp , h is a d v ic e , and his fr ie n d s h ip , I a m m o s t
g r a te fu l.
F r e d B la c k n e d , T im S e a s te d t, D e r e k C ra ig h e a d , P e te H u sby,
and D ic k R u s s e ll h e lp e d w ith f ie ld w o r k on N o r th T w in Is la n d .
W ith o u t
t h e ir h a rd w o r k and good h u m o r f o r m o n th s on end, th is p r o je c t cou ld
n e v e r have b een conducted.
H en k K ilia a n a s s is te d in g a th e rin g and o rg a n iz in g e q u ip m e n t
and D e r e k C ra ig h e a d p ro v id e d m e w ith a p h o to g ra p h ic r e c o r d of th e
p r o je c t .
W h ile in F o r t G e o rg e , Q u e b e c , m a n y p e o p le h e lp e d m e .
I
e x te n d s p e c ia l th an ks to th e m and to th e p e rs o n n e l o f F e c te a u T r a n s p o r t
A e r ie n .
ii
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T h e fo llo w in g a g e n c ie s p ro v id e d fin a n c ia l s u p p o rt;
th e
C a n a d ia n W ild lif e S e r v ic e , th e U . S. B u re a u of S p o rt F is h e r ie s and
W ild lif e , th e M o n ta n a C o o p e ra tiv e W ild lif e R e s e a rc h U n it * ,
N a tio n a l G e o g ra p h ic S o c ie ty .
and th e
F o r t h e ir a id , I a m e s p e c ia lly g r a te fu l.
E r i c and R o b e rta N e ls o n p ro v id e d e x te n s iv e help d u rin g th e
p r e p a r a tio n of th e m a n u s c rip t; m y thanks to th e m f o r t h e ir a d v ic e and
p a tie n c e .
F in a lly , I w o u ld li k e to th a n k tw o p o la r b e a rs w ho p ro v e d to
b e g o o d -n a tu re d at tim e s w hen it r e a l l y cou nted.
W ith o u t t h e ir c o o p e r ­
a tio n th is s tu d y m ig h t not h a ve been c o m p le te d .
* T h e B u r e a u o f S p o rt F is h e r ie s and W i ld lif e , M o n ta n a F is h
and G a m e D e p a r tm e n t, U n iv e r s it y o f M o n ta n a , and th e W ild lif e
M a n a g e m e n t In s titu te , C o o p e ra tin g .
iii
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TABLE
OF
CONTENTS
Page
A C K N O W L E D G M E N T S ......................................................................................
ü
L IS T
OF
T A B L E S .............................................................................................
vi
L IS T
OF
F I G U R E S .............................................................................................
v ii
I N T R O D U C T I O N .................................................................................
1
STUDY
A R E A .................................................................................
4
L o c a t i o n ......................................................................................
C l i m a t e .............................................................................................
T o p o g ra p h y ......................................................................................
V e g e t a t i o n ..............................................
F a u n a .............................................................................................
A c c e s s to th e i s l a n d ..................................................................
D u ra tio n o f F ie ld Seasons on th e Is la n d
. . . .
4
4
7
9
10
12
12
M E T H O D S ..............................................................................................
13
C a p tu rin g and M a r k i n g ............................................................
O b s e r v a t i o n ................................................................................
C ensus T e c h n i q u e s ...................................................................
13
16
18
R E S U L T S ..............................................................................................
21
A r r i v a l of B e a r s on N o r th T w in I s l a n d ...........................
A n n u a l M o v e m e n ts o f N o r th T w in Is la n d B e a r s .
.
A c t iv it y P a t t e r n s ..................................................................
.
F o o d H a b i t s ................................................................................
D is p e r s io n of B e a r s on N o r th T w in Is la n d
. . .
21
25
25
27
31
CHAPTER
I.
II.
III.
IV .
IV
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CHAPTER
V.
V I.
Page
D I S C U S S I O N ........................................................................................
40
A n n u a l M o v e m e n t s ..................................................................
A c t iv it y P a t t e r n s .........................................................................
D i s p e r s i o n ......................................................................................
40
41
42
S U M M A R Y ...............................................................................................
45
L IT E R A T U R E
C IT E D
.
47
A P P E N D IX
I.
II.
III.
K O L M O G O R O V -S M IR N O V A N A L Y S IS O F A C T I V I T Y
P A T T E R N S .............................................................................................
49
M A P S S H O W IN G T H E D IS P E R S IO N O F B E A R S O N
N O R T H T W IN IS L A N D
.................................
57
D IS P E R S IO N O F P O L A R
BEARS ALONG TH E
SO U TH W E S TE R N CO ASTO F HUDSON B A Y
. .
67
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.
L IS T O F
TABLES
T a b le
1.
2.
3.
4.
5.
6.
Page
M e a n H ig h and L o w T e m p e r a tu r e s f o r J u ly in th e
J a m e s B a y A r e a ................................................................
7
O b s e rv a tio n s of M a rk e d B e a rs on N o r th T w in Is la n d ,
S u m m e r and F a l l , 1 9 7 0 ..................................................................
A bundance of B e a rs on Is la n d s A d ja c e n t to N o rth
T w in Is la n d , 1 9 7 1 .........................................................
23
24
L o c a tio n o f I n i t i a l M a r k in g f o r M a r k e d B e a rs O b s e rv e d
on N o rth T w in Is la n d , S u m m e r and F a l l , 1970 . . .
26
T im e D e v o te d b y P o la r B e a rs to C e r t a in A c t iv it ie s
D u rin g D a y lig h t, A u g u st and S e p te m b e r,
1969 and 1970 ......................................................................................
28
M e a s u re m e n t of th e D is p e r s io n of B e a rs on N o rth T w in
Is la n d , 1970 and 1 9 7 1 , f r o m A e r ia l C en su ses
. . .
33
VI
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L IS T
OF
F IG U R E S
Page
F ig u r e
1.
M a p of
Lidson B a y .........................................................................
5
2.
M a p of
im es B a y ........................................................................
.
6
3.
M a p of
o rth T w in I s l a n d ............................................................
8
4.
M ap
a p of N o r th T w in Is la n d , Show ing L o c a tio n s of
S n a re s , 1970
14
T ra n s e c ts F lo w n o v e r N o r th T w in Is la n d D u rin g
C en su ses in 1970 and 1 9 7 1 ........................................................
20
S easo n al In c r e a s e in N u m b e rs o f P o la r B e a r s on
N o rth T w in Is la n d , 1 9 7 1 , as D e te r m in e d b y
A e r i a l C e n s u s ................................................................................
22
M a p o f N o rth T w in Is la n d , Show ing A p p r o x im a te
D is p e r s io n o f C r o w b e r r ie s , 1 9 7 1 ........................................
30
R V a lu e s R e s u ltin g f r o m N e a r e s t N e ig h b o r A n a ly s is
o f the D is p e r s io n of P o la r B e a r s on N o r th T w in
Is la n d in 1970 and 1 9 7 1 ............................................................
34
c V a lu e s R e s u ltin g f r o m N e a r e s t N e ig h b o r A n a ly s is
o f the D is p e r s io n of P o la r B e a rs on N o r th T w in
Is la n d in 1970 and 1 9 7 1 ............................................................
35
L o c a tio n s o f a l l B e a r s Seen on N o r th T w in Is la n d
D u r in g A e r i a l C en su ses in 1970
37
L o c a tio n s of a l l B e a r s Seen on N o r th T w in Is la n d
D u rin g A e r i a l C e n s u s e s in 1 9 7 1 .........................................
38
L o c a tio n s of a l l B e a r s Seen on N o r th T w in Is la n d
D u rin g A e r i a l C e n su s e s in 1970 and 1971
.
.
39
5.
6.
7.
8.
9.
10 .
1 1.
12.
V ll
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.
.
CHAPTER
I
IN T R O D U C T IO N
B e tw e e n 1960 and 1 9 6 5 , C a n ad a , D e n m a r k , N o rw a y , th e
U n ite d S ta te s , and th e S o v ie t U n io n e n te re d in to an in te r n a tio n a l p r o ­
g r a m to g a th e r in fo r m a tio n on th e b io lo g y of th e p o la r b e a r (U rs u s
m a r it im u s ).
T h e p o s s ib ility th a t r e c e n t h e a v y h a rv e s ts of p o la r b e a rs
w e r e p la c in g th e m in d a n g e r of e x tin c tio n , and th e re c o g n itio n th a t
p o la r b e a r s w e r e of e c o n o m ic v a lu e to n o r th e r n c o m m u n itie s , s t im u ­
la te d th e fiv e c o u n trie s to b e g in o r in te n s ify r e s e a r c h on th e s p e c ie s .
T h e h a rv e s t of p o la r b e a r s in th e C a n a d ia n A r c t ic in c r e a s e d
f r o m an a n n u a l k i l l o f a p p r o x im a te ly 100 in th e 1 9 3 0 's and 1 9 4 0 's to
a p p ro x im a te ly 550 p e r y e a r in th e 1 9 5 0 's ; in s o m e a r e a s , one t h ir d of
th e k i l l c o n s is te d of cubs (H a rin g to n , 1 9 6 1 ).
In G re e n la n d , th e a n n u a l
h a r v e s t of a p p ro x im a te ly 100 b e a r s has r e m a in e d con stan t s in c e 1920
(U .S . G o v t ., 1 9 6 6 ).
T h e a n n u a l k i l l in N o rw a y g r a d u a lly d e c re a s e d
d u rin g th e p o s tw a r y e a r s (1 9 4 6 -1 9 6 5 ), a v e ra g in g 324; N o rw e g ia n
b io lo g is ts b e lie v e d th a t th e re d u c e d h a r v e s t r e s u lte d p r i m a r i l y f r o m
d e c re a s e d hu n tin g p r e s s u r e (ib id . ).
A f t e r 10 y e a r s w ith an n u a l
h a r v e s ts of a p p r o x im a te ly 2 0 0 b e a r s in A la s k a , no d e c lin e in n u m b e rs
w as no ted (ib id . ).
P o la r b e a r p o p u la tio n s in th e S o v ie t U n io n w e r e so
1
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d e p le te d b y 1955 th a t a l l hu nting o f p o la r b e a r s w a s p r o h ib ite d
(ib id , ).
In th e p a s t, th e e c o n o m ic im p o r ta n c e of p o la r b e a rs has b een
e x p re s s e d as p r ic e s p a id f o r r a w h id es (H a rin g to n , 1 9 6 1 ).
I b e lie v e
th e in d ic a to r of v a lu e used b y A la s k a , an e s tim a te o f th e to t a l in c o m e
to th e s ta te r e s u ltin g f r o m p o la r b e a r h u n tin g , is m o r e r e a l is t ic .
In
1 9 6 5 , f o r e x a m p le , an e s tim a te d $ 4 5 0 ,0 0 0 w as d e r iv e d f r o m th e
h a rv e s tin g of 292 b e a r s ( U .S . G o v t. , 1 9 6 6 ).
T h is w a s a p p r o x im a te ly
$ 1 , 550 p e r a n im a l as opposed to $ 1 5 0 -$ 2 0 0 p e r r a w h id e a t th a t t im e
(H a rin g to n , 1 9 6 1 ).
T h u s , th e e c o n o m ic im p o r ta n c e o f p o la r b e a r s to
n o rth e r n c o m m u n itie s , a lr e a d y a s ig n ific a n t f a c t o r , b ec o m e s even
m o r e n o te w o rth y w hen th e e c o n o m ic v a lu e of a c tiv it ie s p e r ip h e r a l to
p o la r b e a r h a rv e s tin g is c o n s id e re d .
In S e p te m b e r 1 9 6 5 , a c o n fe re n c e w a s h e ld in F a ir b a n k s ,
A la s k a , to e s ta b lis h g u id e lin e s f o r th e c o o rd in a tio n of r e s e a r c h and
exchange of in fo r m a tio n b e tw e e n th e f iv e c o u n trie s h a v in g p o p u la tio n s
of p o la r b e a r s .
P a r tic ip a n ts in th is c o n fe re n c e , and tw o subsequent
ones in M o rg e s , S w itz e rla n d , in 1968 and 1 9 7 0 , re c o m m e n d e d th e
a c q u is itio n of b a s ic l i f e h is t o r y in fo r m a tio n such as food h a b its , a g e s e x c o m p o s itio n , d e n s ity , and lo c a l and lo n g -r a n g e m o v e m e n t p a tte rn s
(th ro u g h e x te n s iv e ta g g in g p r o g r a m s ).
P a r t ic ip a t io n b y g ra d u a te
studen ts in th e s e in v e s tig a tio n s w as d e c la r e d d e s ir a b le .
In lin e w ith
th e s e re c o m m e n d a tio n s , th e C a n a d ia n W ild lif e S e r v ic e , U . S. B u re a u
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of S p o rt F is h e r ie s and W ild lif e , and the M o n ta n a C o o p e ra tiv e W ild lif e
R e s e a rc h U n it jo in t ly s u p p o rted th is s tu d y on N o r th T w in Is la n d in
J a m e s B a y , N o rth w e s t T e r r i t o r i e s .
T h e o b je c tiv e s o f th is s tu d y w e r e to:
1.
d e s c rib e th e y e a r - t o - y e a r m o v e m e n ts o f b e a r s s e e n on
th e is la n d in o r d e r to d e te rm in e th e c o n tin u ity of use of th e is la n d b y
in d iv id u a ls ;
2.
d e s c rib e th e a c t iv it y - t im e budget of th e b e a r s (th e a m o u n t
o f t im e devoted to th e m a in c a te g o rie s o f b e h a v io r);
3.
d e s c rib e th e s u m m e r food h a b its o f p o la r b e a r s on N o rth
T w in Is la n d ;
4.
d e s c rib e th e s u m m e r m o v e m e n ts of b e a rs and a s c e r ta in
how long th e y r e m a in on th e is la n d ;
5.
r e c o r d the d is p e rs io n of b e a r s on th e is la n d ;
6.
m e a s u re th e s iz e and s tr u c tu r e o f th e s u m m e r p o p u latio n ;
7.
e v a lu a te th e e c o lo g ic a l r o le of th e is la n d f o r p o la r b e a rs
in J a m e s B a y .
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CHAPTER
STUDY
II
AREA
L o c a tio n
N o rth T w in Is la n d is s itu a te d in c e n tr a l J a m e s B a y (F ig . 1) at
la titu d e 5 3 °2 0 * N o r th and lo n g itu d e 8 0 ° 0 0 ' W e s t.
T h e is la n d is a p p ro x ­
im a t e ly 7. 5 m ile s w id e and 11 m ile s long w ith an a r e a , b ecau se of
s h o re lin e i r r e g u l a r i t i e s , of 50 s q u a re m ile s .
South T w in Is la n d ,
w h ic h is ro u g h ly tw o th ir d s th e s iz e o f N o r th T w in , lie s 10 m ile s to
th e south.
D is ta n c e s to n e a r e s t s e ttle m e n ts , m a in la n d , and o th e r
is la n d s a r e in d ic a te d in F ig . 2 .
C lim a t e
N o rth T w in Is la n d has a s u b a rc tic c lim a te .
w ind s p r e v a il.
Ic e is continuous a ro u n d m o s t o f th e is la n d f r o m e a r ly
J a n u a ry to m id -J u n e .
D e c e m b e r.
N o r th w e s te r ly
F lo e ic e o c c u rs n e a r th e is la n d in J u ly and
B re a k u p c h a r a c t e r is t ic a lly in v o lv e s a m o v e m e n t of ic e
r a f t s to th e n o rth , in to H udson B a y (B e a ls and Shenstone, 1 9 6 8 ).
Ic e
fo r m a tio n in J a m e s B a y p ro c e e d s f r o m th e is la n d s and m a in la n d
to w a rd s th e open w a t e r .
J a m e s B a y does not c o m p le te ly f r e e z e o v e r
d u rin g th e w in te r ; th e r e a r e a lw a y s s o m e open lea d s o ff th e co a sts of
th e is la n d s .
4
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NORTH W
TERRITORIES
FOXE
B A SIN
O
HUDSON
S fR A IT
HUDSON
BAY
CHURCHILL
QU EBEC
BELCHER
MA N
W IN IS K
ISLANDS
JAMES
BAY
ORT
GEORGE
NORTH TW IN
ISLA ND
ONEE
O NTARIO
SOO m i l # *
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
/N
N
NORTH
ISLAND
BEAR
ISLAND
BARE
ISLAND
TW IN
GREY G O O S E
ISLAND
ISLAND
JAM ES
SOUTH
LONG
TW IN
FORT GEORGE
ISLA ND
SPENCER
IS LA N D
WALTER
ISLA N D
AK IM ISKI
I SLAND
P AIN T
HILLS
ATTAWAPISKiV
BAY
F OR T
ALBANY
EASTMAIN
CHARLTON
RUPERT
HOUSE
MOOSONEE
ICO
miles
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ISLAND
7
D u rin g the s u m m e r , te m p e r a tu r e s on N o rth T w in Is la n d f a ll
w ith in the ra n g e of te m p e r a tu r e s e n c o u n te re d a t s e ttle m e n ts alo n g the
J a m e s B a y coast (T a b le 1),
TABLE
1.
M e a n H ig h and L o w T e m p e r a tu re s f o r
J u ly in th e J a m e s B a y A r e a
M e a n H ig h
M e a n Lo w
M oosonee^
70° F.
47° F.
N o rth T w in Is la n d ^
68° F .
47° F.
F o r t G e o rg e ^
61° F.
43° F.
S ite
^ E r o m C an ad a D e p a r tm e n t of T r a n s p o r t
m e te o r o lo g ic a l r e c o r d s , a v e ra g e o f s e v e r a l y e a rs
(B e a ls and Shenstone, 1 9 6 8 ).
^ F r o m m a x im u m -m in im u m t h e r m o m e te r
a t c a m p s ite . N o r th T w in Is la n d , 1 9 70 .
T o p o g ra p h y
N o rth T w in Is la n d is e s s e n tia lly f la t w ith a la r g e n u m b e r of
s h a llo w la k e s ( F ig . 3 ).
A r id g e , v a r y in g in a ltitu d e f r o m 20 to 135
fe e t, n e a r ly rin g s th e is la n d ju s t in la n d f r o m th e b e a c h .
T h e rid g e
is r id d le d w ith b e a r dens on th e s o u th e rn and e a s te rn c o a s ts .
T h e is la n d is com po sed of sand s u b s tra te w h ic h is obvious
e x c e p t in th e low in t e r la k e r e g io n w h e r e th e r e is an e x te n s iv e o v e r ­
b u rd e n of p e a t.
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
5
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X
V e g e ta tio n
X e r ic uplands and h y d r lc lo w la n d s on N o r th T w in Is la n d
c o n s titu te tw o to p o g ra p h ic ty p e s , e a ch w ith d is tin c tiv e f lo r a .
uplands a r e w e ll- d r a in e d sand and g r a v e l r id g e s .
The
T h e lo w la n d s c o n ­
s is t of th e in t e r i o r a r e a and sedge m ead o w s lo c a te d b e tw e e n th e r id g e
and b e a c h on th e e a s te rn s id e o f th e is la n d .
A p p r o x im a te ly 75 p e r cent
of th e is la n d is w e tla n d and 2 5 p e r c e n t is d r y u p la n d .
T w o v e g e ta tio n a l c o m m u n itie s o c c u r on th e uplands; th o se
s ite s exposed to th e a b r a s iv e e ffe c ts of b lo w n ic e c ry s ta ls in the
w in t e r , and tho se s h e lte re d f r o m such e ffe c ts .
E x p o s e d s ite s a r e
c h a r a c te r iz e d b y an e x t r e m e ly lo w (le s s th a n 6 in c h e s ) v e g e ta tio n a l
p r o f ile .
T h e w illo w s p e c ie s (e. g . , S a lix r e t ic u la t a ) a r e p r o s t r a t e .
O th e r t y p ic a l v a s c u la r p la n ts a r e D r y a s in t e g r if o lia , V a c c in iu m
u lig in o s u m ,
V . V it is - id a e a , A rc to s ta p h y lo s a lp in a , S a x ifra g a
o p p o s itifo lia , S. a iz o o n , E p ilo b iu m la t if o liu m , E ly m u s a r e n a r iu s ,
P y r o la r o tu n d ifo lia , P . u lig in o s a , and L in n a e a b o r e a lis .
T h e s h e lte re d s ite s h av e a v e g e ta tio n a l p r o f ile of a p p r o x i­
m a te ly 2 to 24 in c h e s .
E r e c t s p e c ie s o f w illo w , B e tu la g la n d u lo s a ,
S h e p h e rd ia c a n a d e n s is . R h o d o d en d ro n la p p o n ic u m . L e d u m d e c u m b e n s ,
and E p ilo b iu m a n g u s tifo liu m a r e t y p ic a l of th e s e s ite s .
B o th th e s h e lte r e d and expo sed p la n t c o m m u n itie s h av e an
e x te n s iv e g rou nd l a y e r o f lic h e n s and c r o w b e r r y (E m p e tr u m n ig r u m ).
B e c a u s e o f its abund ance, c r o w b e r r y is c a p a b le of p ro d u c in g la r g e
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
10
b e r r y c ro p s w h ic h , w hen th e y o c c u r, p ro v id e a m a jo r food s o u rc e f o r
b e a rs .
T w o s u b d iv is io n s o f th e lo w la n d s , t a ll w illo w sw am ps and
sedge m e a d o w s , h ave a g rou nd la y e r of m o s s e s .
T h e sedge m ead ow s
a r e com posed of sed g es, C a lth a p a lu s t r is , E r io p h o r u m a n g u s tifo liu m ,
and P a r n a s s ia p a lu s t r is .
T h e t a ll w illo w a r e a s s u p p o rt a t le a s t th r e e
sp e c ie s of w illo w , S a lix a la x e n s is ,
S. c o r d if o lia , and S. p la n if o lia .
M a n y o th e r lo w la n d s p e c ie s a r e found in th e s e tw o b ro a d s u b d iv is io n s
o f th e lo w la n d s .
A few s m a ll stands o f P ic e a m a r ia n a a r e s c a tte re d about the
is la n d .
T h e m a x im u m h e ig h t o f th e s e tr e e s is a p p ro x im a te ly 9 fe e t.
L a r i x la r ic in a is le s s abundant; 20 to 30 in d iv id u a l p la n ts , none o v e r
4 fe e t t a l l , o c c u r on th e is la n d .
Fauna
D u rin g th is s tu d y , th e o n ly t e r r e s t r i a l m a m m a ls o b s e rv e d on
N o rth T w in Is la n d w e r e p o la r b e a r s , a r c t ic fo xe s (A lo p e x la g o p u s ),
and re d foxes ( V u lp e s v u lp e s ).
N u m b e rs o f a r c t ic fo x e s v a r ie d g r e a tly f r o m y e a r to y e a r .
In 1969 and 1 9 70, fo xes w e r e r a r e l y s ig h te d , b u t in 1 9 7 1 , th e y w e r e
seen a lm o s t e v e r y d a y .
T w e lv e w e r e c o lo r m a r k e d w ith p a in t p e lle ts
shot f r o m a COg p is to l and an e s tim a te d 12 o th e r in d iv id u a ls w e r e
s een .
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
11
R e d fo xes w e r e o b s e rv e d o n ly in N o v e m b e r and D e c e m b e r,
1971.
T h e g r e a te s t n u m b e r s e e n a t one t im e w as tw o .
R in g e d s e a ls (P h o c a h is p id a ) and b e a rd e d o r s q u a r e flip p e r
s e a ls (E rig n a th u s b a r b a tu s ) w e r e id e n tifie d b y c o lle c tin g a s p e c im e n of
each.
B o th s p e c ie s w e r e c o m m o n ly seen d u rin g canoe t r ip s aro u n d
th e is la n d .
A c c o rd in g to M a n s fie ld (1 9 6 7 ), th e s e a r e th e o n ly tw o
s p e c ie s of s e a ls in J a m e s B a y .
W h ite w h a le s (D e lp h in a p te ru s le u c a s )
w e r e fr e q u e n tly s een f r o m a i r c r a f t .
W a te r fo w l w e r e abundant on th e is la n d .
F r o m o b s e rv a tio n s
o f b ro o d s and n e s ts , th e fo llo w in g s p e c ie s w e r e know n to b re e d :
C an ad a goose (B r a n ta c a n a d e n s is ),
g re e n -w in g e d te a l (A n as
c a r o lin e n s is ), b la c k duck (A n as r u b r ip e s ), p in t a il (A n as a c u ta ),
le s s e r scaup (A y th y a a f f in is ), olds qua w (C la n g u la h y e m a lis ),
co m m o n e id e r (S o m a te ria m o U is s im a ).
seen on o r n e a r th e is la n d w e re :
and
O th e r s p e c ie s c o m m o n ly
c o m m o n s c o te r (O id e m ia n ig r a ),
w h ite -w in g e d s c o te r (M e la n itt a d e g la n d i), c o m m o n m e r g a n s e r (M e rg u s
m e r g a n s e r ), r e d - b r e a s t e d m e r g a n s e r ( M e rg u s s e r r a t o r ), com m o n
lo o n (G a v ia i m m e r ), a r c t ic lo o n (G a v ia a r c t i c a ), and r e d -th r o a te d
lo o n (G a v ia s t e lla t a ).
T h e n e s tin g p o p u la tio n of C a n ad a g e e s e w as e s tim a te d a t
200 p a ir s .
In 1969 and 1 9 7 0 , th e flo c k s c o n ta in e d a p p r o x im a te ly
th r e e g o s lin g s p e r p a i r o f a d u lts .
N o g o s lin g s w e r e s ee n in 19 7 1 .
W illo w p ta r m ig a n (L a g o p u s la g o p u s ) v a r ie d in abundance
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12
d u rin g the p e r io d of s tu d y .
In 1969 and 1 9 7 0 , I e s tim a te d th e
p ta r m ig a n p o p u la tio n a t 1, 500 to 2 ,0 0 0 b ir d s .
tio n w as a p p ro x im a te ly 2 0 0 b ir d s .
In 1 9 7 1 , th e p o p u la ­
A s in th e c a s e o f g e e s e , young
w e r e c o m m o n in 1969 and 1 9 7 0 , b u t none w e r e seen in 1971.
N o rth T w in Is la n d has a lw a y s b e e n e s s e n tia lly u n in h a b ite d b y
m a n ( H om o s a p ie n s ) (R . L o u t t it, p e r s . c o m m . ).
O c c a s io n a lly , it
w as v is ite d b y c re w s f r o m b o a ts fo r c e d in to th e is la n d 's h a r b o r by
s to r m s , o r , v e r y r a r e l y , b y re s id e n ts of c o a s ta l s e ttle m e n ts .
A c c e s s to th e Is la n d
T h e e a s ie s t w a y to r e a c h N o rth T w in Is la n d is
fro m F o r t
G e o rg e , Q u e b e c , v ia F e c te a u T r a n s p o r t A e r ie n , L te e . F lo a t-e q u ip p e d
a i r c r a f t can la n d on th e b a y o ff th e e a s te r n c o as t of th e is la n d d u rin g
c a lm w e a th e r, o r w h e n th e r e is a m ild w e s t w in d .
In w in t e r , lig h t
a i r c r a f t equipped w ith s k is c a n la n d on th e fr o z e n la k e s o r th e b a y ic e .
In N o v e m b e r 1 9 71, th e ic e on th e b a y w as not th ic k enough to la n d
upon.
A t th a t t im e , a p ilo t, e x p e rie n c e d in such la n d in g s , la n d ed a
lig h t, tw in -e n g in e d a i r c r a f t ( B r it t a n - N o r m a n Is la n d e r on w h e e ls ) on
an e s k e r ( g r a v e l r id g e ) 1 m ile n o rth o f c a m p .
D u r a tio n of F ie ld Seasons on th e Is la n d
T h e p e rio d s s p e n t on th e is la n d w e re :
1969:
J u ly 15 to S e p te m b e r 15
1970:
J u ly 15 to O c to b e r 24
1971:
J u ly 25 to O c to b e r 2 2 , N o v e m b e r 12 to J a n u a ry 5, 1 97 2.
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
CHAPTER
III
M ETHODS
C a p tu rin g and M a r k in g
D u rin g m o s t of th e 1970 f ie ld seas o n , a t r a p lin e w as
o p e ra te d to c a p tu re and m a r k p o la r b e a r s (F ig . 4 ).
A ld r ic h s n a re s
w e r e used in cubby tr a p s ite s (J o n k e l and C o w an , 1 9 7 1 ).
S ince 19 66,
th e C a n a d ia n W ild lif e S e rv ic e has used th is m eth o d w ith no e v id e n c e of
in ju r y to c a p tu re d b e a r s , e x c e p t f o r s o m e s lig h t a b ra s io n s f r o m th e
c a b le on th e fo r e fo o t.
s e a l fa t w as added.
B a it w as baco n and s a rd in e s ; w hen p o s s ib le ,
T r a p s w e r e checked d a ily to e n s u re th a t a b e a r
did no t spend m o r e th a n 24 h o u rs in a s n a re and th a t th e b a it had not
b een s to le n .
In 1971, th e abundance o f fo xe s p re v e n te d the o p e ra tio n
of a t r a p lin e .
S n a re d b e a r s w e r e im m o b iliz e d b y in je c tin g p h e n c y c lid in e
h y d ro c h lo rid e (S e rn y la n , B io - C e u tic L a b o r a to r ie s ) in t r a m u s c u la r ly
w ith a P a lm e r C a p -C h u r C O 2 p is to l and d a r t . ^
D a r ts w e r e u s u a lly
f ir e d in to th e s h o u ld e r o r b a s e o f the n e c k of th e s n a re d b e a r f r o m a
ra n g e o f 15 fe e t.
T h is d ru g w as used s u c c e s s fu lly on g r i z z l y b e a rs
^U se of tr a d e and c o m p an y n a m e s does not c o n s titu te an
e n d o rs e m e n t o f a p ro d u c t o r c o m p a n y b y th e s p o n s o rin g a g e n c ie s .
13
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
5
rld««
high
point
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
X
15
(U rs u s a r c t o s ) (C ra ig h e a d and C r a ig h e a d , 1 9 6 5 ) and p o la r b e a rs
(J o n k e l, 1967; L a r s e n , 1967; L e n tf e r , 1 9 6 8 ).
D o sag es of 0 . 6 to
0 . 7 m g /lb of b o d y w e ig h t w e r e a d m in is te r e d , b a s e d on e s tim a te d
w e ig h ts of s n a re d b e a r s .
B e c a u s e of th e w id e la titu d e of th e d ru g , w e
could d e te rm in e d ru g dosages b y e s tim a tin g th e w e ig h t of a c a p tu re d
b e a r.
E s tim a te s of w e ig h t im p r o v e w ith e x p e rie n c e .
P r o m a z in e
h y d ro c h lo rid e (S p a rin e , John W y e th and B r o s . ) w as used as an a n t i­
c o n v u ls a n t in dosages e q u a l to th o s e o f th e im m o b iliz in g d ru g .
A l l c a p tu re d b e a rs w e r e m a r k e d w ith a lip ta tto o , e a r ta g s ,
and a dye m a r k on th e f u r .
T h e lip ta tto o , a p p lie d w ith a s ta n d a rd
p a i r of c a ttle ta tto o in g p lie r s , w a s used as a p e rm a n e n t m a r k e r .
T a g s can p u ll out, w h e re a s a ta tto o is p e rm a n e n t and p e r m its id e n t i­
fic a tio n i f th e b e a r is k ille d o r r e c a p tu re d .
E a r m a r k e r s w e r e p la s tic
rib b o n s and n y lo n c a ttle ta g s , c o lo re d and n u m b e re d .
r e c e iv e d one ta g and one rib b o n .
Each ear
A s y s te m of c o lo r codes w as used
so th a t a n im a ls cou ld b e id e n tifie d s im p ly b y a s c e rta in in g th e c o lo r
and p o s itio n of tw o o f th e fo u r m a r k e r s , th e r e b y e lim in a tin g the
n e c e s s ity f o r m u ltip le r e c a p tu r e s .
T h e p r a c tic e of e a r -ta g g in g w as
used s u c c e s s fu lly , not o n ly on p o la r b e a r s (J o n k e l, 1 9 6 7 ), but a ls o on
b la c k ( U rs u s a m e r ic a n u s ) and g r i z z l y b e a r s (C ra ig h e a d et a l . , 1960;
J o n k e l and C o w an , 1971;
T r o y e r and H ens e l, 1 9 6 1 ).
T h r e e d if f e r e n t dyes w e r e t r i e d on c a p tu re d b e a rs :
L a n o b ra n d , N y a n z o l, and N e l-S p o t p a in t p e lle t s .
T h e o n ly dye th a t
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16
p ro v e d s a tis fa c to r y , b o th in v i s i b i l i t y and d u r a b ility (s e v e r a l m o n th s ),
w a s N y a n z o l.
In a d d itio n to th e 12 b e a r s m a r k e d in th e above m a n n e r (both
dye and ta g s ) on N o rth T w in Is la n d , 40 b e a r s w e r e m a r k e d in the
J a m e s B a y a r e a b y th e C a n a d ia n W ild lif e S e rv ic e d u rin g th e s p rin g s
of 1 9 6 8 , 1 9 69, and 1 9 7 0 .
T h o s e b e a rs w e r e im m o b iliz e d f r o m a h e l i ­
c o p te r w h ile th e b a y w a s c o v e re d b y ic e ; s o m e w e r e o b s e rv e d o r
re c a p tu re d on N o r th T w in Is la n d .
B y th e f a l l of 1 9 7 0 , 52 b e a r s had
b e e n m a r k e d in th e J a m e s B a y a r e a .
O b s e rv a tio n
P o la r b e a r s w e r e lo c a te d f r o m v a n ta g e p o in ts on th e is la n d
w h e re e x te n s iv e a re a s cou ld be scan n ed .
O n th e p r im a r y o b s e rv a tio n
p o in t, a p p ro x im a te ly 40 f e e t abo ve th e s u rro u n d in g a r e a , a 1 0 -fo o t
to w e r w as e re c te d .
T h is w as 2 . 5 m ile s s o u th w est o f c a m p .
If b e a rs
w e r e not s e e n f r o m th e to w e r , I lo o k e d f o r th e m f r o m s ite s th a t
o ffe re d co m m an d in g v ie w s o f th e s o u th e rn p o rtio n of th e is la n d .
A tte m p ts to o b s e rv e b e a r s on th e n o r th e r n h a lf of th e is la n d w e r e
u n s u c c e s s fu l b e c a u s e th e r e w e r e no good o b s e rv a tio n a l s ite s .
I s ta lk e d b e a r s f r o m do w nw in d and o b s e rv e d th e m f r o m a
d is ta n c e of 200 y a rd s o r m o r e .
F r o m e x p e rie n c e , I le a r n e d th a t th e
b e a r s co u ld not r e a d ily d is c e r n m o v e m e n t beyo nd 2 00 y a r d s .
v a tio n s w e r e m a d e w ith Z e is s
O b s e r­
1 5 X 6 0 b in o c u la rs and a R e d fie ld
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17
1 5 X - 6 0 X v a r ia b le s p o ttin g s c o p e .
F o r tim in g , H e u e r J u n io r s to p ­
w a tc h e s w e r e u sed .
T r a v e lin g , fe e d in g , and r e s tin g w e r e th e th r e e c la s s ific a tio n s
w h ic h I used to d e s c rib e th e a c tiv itie s of b e a r s .
T r a v e lin g in v o lv e d
th e m a in te n a n c e of a m o d e r a te p a c e in a co n stan t d ir e c tio n w ith th e
h ead h e ld w e ll above th e g ro u n d .
F e e d in g b e a r s w a lk e d in a s lo w ,
m e a n d e rin g m a n n e r w ith t h e ir noses o n ly an in c h o r so above th e
g ro u n d .
S ittin g , ly in g , o r flo a tin g m o tio n le s s
in th e w a t e r w as
c la s s ifie d as r e s tin g b e h a v io r .
B e c a u s e o f th e t im e r e q u ir e d to lo c a te a b e a r in th e m o rn in g ,
to r e t u r n to cam p in th e e v e n in g , and th e d if f ic u lty o f o b s e rv in g b e a r s
a t n ig h t, d ir e c t o b s e rv a tio n s of b e a r s in v o lv e d s o m e u n a v o id a b le
b ia s e s .
A l l o b s e rv a tio n s w e r e m a d e b e tw e e n 062 5 and 2115 h o u rs ,
and 8 8 . 3 p e r ce n t o f o b s e rv a tio n a l t im e w as b e tw e e n 1000 and 1800
h o u rs .
T h u s , th e s a m p lin g o f th e b e a r s ' b e h a v io r w a s h e a v ily b ia s e d
to w a rd th e m id d le of th e d a y,
A s p a tia l b ia s w as g e n e ra te d b y u sin g
th e to w e r as th e m a in s c a n n in g p o in t; th e a c t iv it ie s r e c o rd e d w e r e
o n ly th o se of b e a r s on th e s o u th e rn h a lf of th e is la n d .
In a d d itio n ,
a e r i a l censuses show ed th a t b e a r s spen t at le a s t s o m e o f t h e i r t im e
in a re a s w h e re g ro u n d o b s e rv a tio n s w e r e im p o s s ib le .
B e a rs ly in g in
w illo w th ic k e ts , dens, n a r r o w g u llie s , o r o th e r c o n ce aled p la c e s w e r e
n o t o b s e rv e d f r o m th e g ro u n d ,
and such b e h a v io r w as not p r o p o r ­
t io n a lly r e p r e s e n te d in th e d a ta .
D u r in g 1 9 69 ,
young w e r e not seen on th e is la n d ,
fe m a le s w ith
thus o n ly d a ta f o r lo n e b e a r s
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
18
w e r e c o lle c te d .
A l l th e d a ta c o n c e rn in g th e a c tiv it ie s of f a m ilie s
w e r e c o lle c te d in 1970.
M o s t o b s e rv a tio n s w e r e m a d e on u n m a rk e d b e a r s , and
t h e r e f o r e , a p r e c is e d e te rm in a tio n o f th e n u m b e r of in d iv id u a ls
in v o lv e d w a s im p o s s ib le .
H o w e v e r, e s tim a te s of th e m in im u m
n u m b e r of a n im a ls w e r e p o s s ib le on th e b a s is of c h a r a c te r is tic s such
as s iz e , am o un t of fa t, and s c a r s .
N o fe w e r th a n n in e lo n e b e a rs and
f iv e f a m ily grou ps w e r e used to c o m p ile in fo r m a tio n on a c tiv it y
p a tte r n s .
B e c a u s e i t is m o r e d if f ic u lt to p o s itiv e ly d iffe r e n tia te
b e tw e e n lo n e b e a rs th a n b e tw e e n f a m ilie s , th e f ig u r e o f nin e is v e r y
c o n s e rv a tiv e .
C ensus T e c h n iq u e s
O n S e p te m b e r 2 and 14, 1 97 0, th e b e a r p o p u la tio n on th e
is la n d w as censused f r o m th e g ro u n d and th e p o s itio n of each b e a r
w as noted on m a p s .
O ne o b s e rv e r censu sed th e n o r th e r n h a lf of th e
is la n d and one th e s o u th e rn h a lf.
F if t e e n m in u te s w e r e spent
scann ing w ith b in o c u la rs f r o m each o f 13 p r e d e te r m in e d h ig h p o in ts .
T h e s a m e ro u te s and p o in ts w e r e used on bo th d ays.
T o te s t th e a c c u r a c y o f th e g ro u n d census m e th o d , an a e r ia l
census w as conducted on S e p te m b e r 15.
A s e r ie s of tra n s e c ts (F ig . 5)
w e r e flo w n a t an a ltitu d e of 2 50 to 300 fe e t in a lig h t a i r c r a f t .
o b s e rv e r s w e r e p re s e n t in a d d itio n to th e p ilo t.
Two
W h en a b e a r w as
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
19
s ig h te d , its p o s itio n w a s im m e d ia te ly m a r k e d on a g rid d e d m a p (F ig .
5 ),
E a c h s id e o f th e s q u a re s in th e g r id r e p re s e n te d 3 / 8 m ile and
gave r e a d y r e fe r e n c e to s c a le , th e r e b y f a c ilit a t in g r a p id p la c e m e n t of
e a c h b e a r 's lo c a tio n on th e m a p .
T h e m a n y d is t in c t iv e ly shaped la k e s
a ls o a id e d th e a c c u ra te lo c a tio n of a l l b e a r s .
A c o m p a ris o n of th e r e s u lts o f th e g ro u n d and a e r ia l censuses
in d ic a te d th a t a e r i a l censu ses w e r e th e m o s t p ro d u c tiv e and a l l s u b ­
sequent censuses w e r e f r o m a i r c r a f t .
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
♦
%
%
m
e
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
CHAPTER
IV
RESULTS
A r r i v a l of B e a r s on N o r th T w in Is la n d
Seven censu ses b e tw e e n J u ly 28 and N o v e m b e r 12, 1 97 1 ,
show ed a g ra d u a l in c r e a s e in n u m b e r of b e a r s a r r iv in g on N o r th T w in
Is la n d (F ig . 6 ).
T h e y co n tin u ed to a r r i v e a f t e r th e ic e had d r ifte d a t
le a s t 20 m ile s f r o m th e is la n d .
T h e r e w as no e v id e n c e of e m ig r a tio n f r o m th e is la n d d u rin g
im m ig r a tio n .
T a g g in g d a ta in d ic a te d th a t b e a r s r e m a in e d on N o rth
T w in Is la n d f o r th e i c e - f r e e seaso n in s p ite o f tra p p in g and o th e r
d is tu rb a n c e s b y m a n .
O n ly th r e e of th e b e a rs c a p tu re d a n d / o r s ig h te d
on th e is la n d w e r e not re s ig h te d o r r e c a p tu re d (T a b le 2 ).
Num ber
583 w as s ig h te d in th e w a te r o ff th e n o r th e r n c o ast of th e is la n d , w as
frig h te n e d , and p o s s ib ly n e v e r c a m e a s h o re .
F e m a le 662 w as tagged
17 days b e fo re w e l e f t th e is la n d in 1 9 7 0 , le a v in g l i t t l e t im e f o r h e r to
b e re s ig h te d .
A ls o , i t w a s r a in in g w hen th e dye w as a p p lie d and h e r
r e s is ta n c e to th e d ru g m a d e h e r so d if f ic u lt to h an dle th a t o n ly tw o
q u ic k ly in s e r te d e a r ta g s w e r e a tta c h e d .
T h u s , she w o u ld not be
e a s ily id e n tifie d and f a il u r e to r e s ig h t h e r on th e is la n d cannot be
ta k e n as p r o o f th a t she l e f t .
T h e o n ly e v id e n c e o f t r a v e l b e tw e e n
21
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
20
lA
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Ul
flfi
u.
O
,0 -
III
m
9
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u
28
J U IY
12
AUGUST
24
AUGUST
12
S iP T f M B E R
3
OCTOBER
22
O C TO B ER
DATE
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
12
NOVEMBER
23
TABLE
2.
O b s e rv a tio n s of M a r k e d B e a rs on N o rth T w in
Is la n d , S u m m e r and F a l l , 1970
N u m b e r and Sex
C a p tu re s
Sightings
T o ta l
583
(M )
0
1
1
62 9
(F )
1
2
3
1
2
3
1
2
3
1
2
3
0
2
2
606
631
(F )
640
635
(M)^
(F )
(F )
636
(F )
0
2
2
602
(M )
0
2
2
637
(F )
0
1
1
638
(F )
2
1
3
2
1
3
639
(F )
645
(F )
5
16
21
661
(F )
1
1
2
1
1
2
609
(M )
662
(F )
1
0
1
663
(F )
1
1
2
608
(M )
1
1
2
14
27
41
In d e n te d n u m b e rs r e p r e s e n t young w ith th e p r e ­
c edin g sow .
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
24
is la n d s d u rin g th e s u m m e r w as the m o v e m e n t of 631 and h e r cub, 640.
T h e y w e r e tagged on South T w in Is la n d in A u g u st 19 70, and w e r e seen
on N o rth T w in Is la n d in O c to b e r of th a t y e a r .
T h e above d a ta in d ic a te d th a t once b e a rs re a c h e d N o r th T w in
Is la n d , th e y did not c o n tin u e to t r a v e l b e tw e e n is la n d s .
O c c a s io n a l
censuses of the is la n d s n e a r N o rth T w in ( r e g u la r censuses w e r e not
p o s s ib le ) show ed th a t few b e a r s w e r e on th e o th e r is la n d s (T a b le 3).
O n O c to b e r 3, 1 9 71, w h en th e p o la r b e a r p o p u la tio n o f N o rth T w in
Is la n d w as 15, o n ly th r e e b e a r s w e r e on South T w in .
TABLE
3.
A b undance of B e a r s on Is la n d s A d ja c e n t to N o rth T w in
Is la n d , 1971
Is la n d
A p p ro x im a te A r e a
in S q u a re M ile s
D a te
N u m b e r of B e a rs
South T w in
33
A u g u st 24
4 (lo n e b e a r s )
South T w in
33
O c to b e r 3
3 (lo ne b e a r s )
Spencer
2
A u g u st 24
2 (lo n e b e a r s )
Spencer
2
O c to b e r 3
0
W a lt e r
1
O c to b e r 3
0
A k im is k i Is la n d , u n lik e th e o th e r is la n d s in J a m e s B a y , is
e x te n s iv e ly fo r e s te d and t h e r e f o r e im p o s s ib le to s u r v e y e f fic ie n t ly
f r o m a fix e d -w in g a i r c r a f t .
H o w e v e r, p o la r b e a rs do o c c u r th e r e
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25
s in c e e ig h t w e r e s e e n a lo n g 60 m ile s o f c o as t on O c to b e r 3, 1 971.
A n n u a l M o v e m e n ts o f N o r th T w in Is la n d B e a rs
N one of th e 30 b e a r s m a r k e d b y th e C a n a d ia n W ild lif e S e rv ic e
in th e s p rin g s o f 1968 and 1969 w e r e s e en on th e is la n d d u rin g th e
s u m m e r of 1969.
T a b le 4 lis t s th e m a r k e d b e a r s o b s e rv e d on N o rth T w in
Is la n d d u rin g th e s u m m e r and f a l l of 1 9 7 0 .
N o ne of th e s e b e a r s w e r e
s e e n on th e is la n d th e fo llo w in g y e a r , n o r w e r e th e y s e en alo n g th e
c o a s t o f Hudson B a y f r o m N o r th T w in Is la n d to C h u r c h ill (A p p e n d ix I ) .
T h e o n ly in fo r m a tio n o b ta in e d d u rin g 1971 c o n c e rn in g th e lo c a tio n of
b e a r s m a r k e d in 1970 w as th e r e c o v e r y o f ta g s f r o m a sow w ith tw o
y e a r lin g s .
T h e s e b e a r s (6 3 5 , 6 3 6 , 6 0 2 ) w e r e shot a t F o r t G e o rg e ,
55 m ile s n o rth e a s t of N o r th T w in , in A u g u s t 1 9 7 1 .
M a rk e d b e a rs w e re
not o b s e rv e d d u rin g censu ses of W a lt e r , S p e n c e r, and South T w in
Is la n d s on A u g u st 2 4 and O c to b e r 3 , 1 9 7 1 .
In 1 9 6 9 , no f a m ilie s w e r e s e e n .
H o w e v e r, in 19 7 0 , a e r i a l
censu ses show ed a t le a s t 11 d if f e r e n t f a m ilie s on th e is la n d .
N a t a lit y
can o n ly p a r t ia l l y e x p la in th e in c r e a s e in n u m b e r of f a m ilie s .
Those
f a m ilie s w h ic h c o n ta in e d y e a r lin g s in 1970 o b v io u s ly e x is te d in 1969
and m u s t have im m ig r a te d to N o r th T w in Is la n d in 1 9 7 0 .
A c t iv it y P a tte r n s
D u r in g s u m m e r , b e a r s s p e n t th e m a j o r it y o f t h e ir t im e
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
CD
■D
O
Q.
C
g
Q.
TABLE
4.
■CDD
Location of In itia l Marking fo r Marked Bears Observed on North Twin Island, Summer
and F a ll, 1970
C/)
C/)
Number
8
(O '
3.
3
"
CD
CD
■D
O
Q.
C
a
o
3
"O
o
CD
Q.
■CDD
638
639*
637
583
629
606
631
640
635
636
602
645
661
609
608
662
663
Sex
Age (1970)
Location of Marking
Date of Marking
F
F
F
M
F
M
F
F
F
F
M
F
F
M
M
F
F
adult
cub
adult
adult
adult
cub
adult
cub
adult
cub
cub
cub^
adult
cub
cub^
adult
cub^
15 m i. NW of Bare Is.
15 m i. NW of Bare Is.
15 m i. S of Bare Is.
G rey Goose Is.
15 m i. SE of G rey Goose Is.
North Twin Is.
South Twin Is.
South Twin Is.
North Twin Is,
North Twin Is.
North Twin Is.
North Twin Is.
North Twin Is.
North Twin Is.
North Twin Is.
North Twin Is.
North Twin Is.
Spring 1970
Spring 1970
Spring 1970
Spring 1969
Spring 1969
August 1970
August 1970
August 1970
Spring 1970
Spring 1970
Spring 1970
August 1970
September 1970
September 1970
September 1970
October 1970
October 1970
Distance fro m
North Twin
84
84
55
37
30
m i.
m i.
m i.
m i.
m i.
• ■
10 m i.
10 m i.
C/)
C/)
^Indented numbers represent young with the preceding sow.
b
These were so litary cubs, possibly orphans.
This cub was with a sow and another cub, neither of which were m arked.
CO
O)
27
r e s t in g , w h ile v e r y l i t t l e t im e w a s spen t on fe e d in g a c tiv itie s (T a b le
5 ).
T o d e te r m in e w h e th e r a s ig n ific a n t d iffe r e n c e e x is te d b e tw e e n
th e b e h a v io r of lo n e a n im a ls and f a m ilie s , a K o lm o g o r o v -S m irn o v
tw o -s a m p le te s t w a s a p p lie d to th e d a ta (A p p e n d ix I ) .
In a l l th r e e
c a te g o rie s o f b e h a v io r (tr a v e lin g , fe e d in g , and r e s tin g ), no s ig n if i­
cant d iffe r e n c e (®^ = 0 . 0 5 ) w as d e te c te d b e tw e e n th e b e h a v io r of lo n e
a n im a ls and f a m ilie s .
M y o b s e rv a tio n th a t th e b e a r s spend l i t t l e t im e fe e d in g w h ile
on th e is la n d d u rin g s u m m e r is f u r t h e r s u p p o rte d b y th e fa t c o n d itio n
of th e a n im a ls upon t h e ir a r r i v a l .
T h e ir g e n e r a l c o n d itio n suggested
th a t th e y could s u r v iv e a s u m m e r b y u t iliz in g t h e ir fa t r e s e r v e s .
A n a e r i a l census on N o v e m b e r 12, 1 97 1 , p r i o r to f r e e z e -u p ,
r e v e a le d 21 b e a r s on th e is la n d .
g ro u n d .
H o w e v e r, fe w w e r e seen f r o m the
In s p ite of th e p re s e n c e of t r a c k in g sn o w , tr a c k s w e r e r a r e l y
s een , in d ic a tin g th a t th e b e a r s w e r e not m o v in g at n ig h t.
T h is o b s e r ­
v a tio n suggested th a t r e s tin g a c t iv it y s t i l l p r e v a ile d o v e r o th e r
a c t iv it ie s .
F o o d H a b its
In 1969 and 1 9 7 0 , c r o w b e r r ie s w e r e abundant and w e r e th e
m a in food f o r p o la r b e a r s on N o r th T w in Is la n d .
N in e ty -o n e p e r cent
of th e 3. 31 h o u rs th a t th e b e a r s w e r e o b s e rv e d fe e d in g w as spent on
c r o w b e r r y p a tc h e s .
C r o w b e r r ie s w e r e m o s t co m m o n on th e open
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
■CDD
O
Q.
C
g
Q.
^
T A B L E 5.
C/)
W
o'
3
0
3
CD
8
Tim e Devoted by P o lar Bears to C ertain A ctivities During Daylight, August and September,
1969 and 1970
Composition
of Group
Number of
Observation
Periods (n)
Feeding
Resting
Total
Traveling
Hours Percentage Hours Percentage Hours Percentage Hours Percentage
(O'
3"
1
3
CD
"n
c
3.
3
"
CD
CD
■D
O
Q.
C
a
o
3
■D
O
Lone Bears
(1969)
29
1:51
2 .4
67:10
8 6 .4
8:44
11.2
77:45
100.0
Fem ales with
Cubs (1970)
10
1:40
4 .9
29:39
87.7
2:29
7 .4
33:48
100.0
AU Bears
(1969 and
1970)
39
3:31
3.2
96:49
86.8
11:13
10.0
111:33
100.0
CD
Q.
■CDD
C/)
C/)
CO
29
(w ith o u t w illo w s ) rid g e s (F ig . 7 ).
a lm o s t e n t ir e ly c r o w b e r r ie s .
F r e s h s c a ts found in 1970 w e re
T h is w as d e te rm in e d b y c o lo r (p u rp le )
and p re s e n c e of c r o w b e r r y s e e d s , w h ic h a r e d is tin g u is h a b le f r o m the
seeds of th e o th e r tw o c o m m o n b e r r ie s on th e is la n d , c r a n b e r r y
( V a c c in iu m V it is - id a e a ) and b a k e d -a p p le b e r r y (Rubus c h a m a e m o ru s ).
T h e c r o w b e r r y c ro p f a ile d in 1971; th e o n ly b e r r ie s found
th a t s u m m e r w e r e s c a tte re d o v e r a s m a ll a r e a .
B e ca u s e of th e
s c a r c ity of b e r r ie s in 1 9 7 1 , b e a r s w e r e not o b s e rv e d fe e d in g in the
open as th e y had b e e n d u rin g 1969 and 1 9 7 0 .
R u s s e ll (1 9 7 1 ) a n a ly z e d p o la r b e a r sc a ts c o lle c te d on N o rth
T w in Is la n d d u rin g 1968 and 1969 and re a c h e d a d iffe r e n t con clu sio n
r e g a rd in g th e im p o rta n c e of c r o w b e r r ie s .
He concluded th a t the
b e a rs fe d p r i m a r i l y on w a te r fo w l, b e r r i e s , g ra s s , and seaw eed
(Fu cus sp. and L a m in a r ia sp . ), in th a t o r d e r o f im p o rta n c e .
By
e x a m in a tio n of fe a th e r s in th e s c a ts , he found th a t oldsquaw s and
s c o te rs w e re m o s t fr e q u e n tly e a te n .
B e c a u s e th e s e ducks w e r e r a r e l y
seen on the is la n d , p o la r b e a r s a p p a re n tly c a p tu re d th e m in the w a te r .
T h is phenom enon w as o b s e rv e d in o th e r p a r ts of the a r c t ic (R u s s e ll,
op. c it. ).
In 1970 and 1 9 7 1 , alth o u g h I w as lo o k in g f o r such b e h a v io r
and fre q u e n tly saw p o la r b e a r s s w im m in g n e a r r a fts of sea du cks,
n e v e r o b s e rv e d a tte m p ts to c a tc h th e m .
I
W h e th e r m y f a ilu r e to
o b s e rv e th e c a p tu re of s ea ducks sh o u ld b e a ttr ib u te d to the d iffic u lty
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
5
%
%
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
31
o f o b s e rv in g b e a r s s w im m in g o ffs h o re , o r to th e absen ce o f such
b e h a v io r d u rin g th e y e a r s c o n c e rn e d , is in d e te r m in a b le .
B e a rs w e r e o b s e rv e d k illin g fo u r g e e s e d u rin g 19 7 0 .
Bear
tr a c k s and th e r e m a in s o f g e es e in d ic a te d th e k illin g of tw o o th e rs .
T h e r e w e r e no le n g th y s ta lk s le a d in g to th e o b s e rv e d k ill s .
B e a rs
a p p e a re d to b lu n d e r in to g ro u p s of m o u ltin g a d u lts and g o s lin g s , as
th e y fe d .
I t r e q u ir e d le s s th a n 5 m in u te s f o r a b e a r to k i l l and ea t a
g o ose.
O n ly once w as a b e a r s e e n e a tin g k e lp (J . J . C ra ig h e a d ,
p e r s . c o m m , ).
T h is s in g le in s ta n c e c o rre s p o n d s w ith R u s s e ll's
c o n c lu s io n th a t k e lp is a v e r y m in o r ite m in th e d ie t o f b e a rs on
N o r th T w in Is la n d .
P o s s ib ly s m a ll m o llu s k s a tta c h e d to th e k e lp
w e r e th e food b e in g s o u g h t.
D u rin g s o m e o b s e r v a tio n a l p e r io d s , i t a p p e a re d th a t the
b e a r s fe d on g r a s s e s .
B e c a u s e of p o o r d ep th p e r c e p tio n w hen
o b s e rv in g f r o m a d is ta n c e of s e v e r a l h u n d re d y a rd s w ith p o w e rfu l
o p tic s , I w as n e v e r a b le to lo c a te th e p r e c is e fe e d in g s ite and
c o n fir m th is o b s e rv a tio n .
D is p e r s io n o f B e a r s on N o r th T w in Is la n d
G ro u n d counts w e r e r e je c t e d as a m e th o d f o r a c c u r a te
m e a s u re m e n t o f n u m b e rs and d is p e r s io n o f b e a r s on th e is la n d .
The
g ro u n d counts m a d e on S e p te m b e r 2 and 14, 1 9 7 0 , show ed 22 and 24
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
32
b e a r s , r e s p e c tiv e ly .
b e a rs .
T h e a e r i a l census of S e p te m b e r 15 showed 39
T h e r e a f t e r , a e r i a l censu ses w e r e used e x c lu s iv e ly b e ca u se
th e y w e r e c o n s id e re d m o r e a c c u ra te th a n g rou nd counts.
N in e m aps
show ing th e d is p e rs io n of b e a r s , as in d ic a te d b y a e r ia l censuses in
1970 and 1 9 71, a r e in A p p e n d ix I I .
T o d e te rm in e th e p a tte r n ado pted b y th e b e a r s , th e n e a r e s t
n e ig h b o r te c h n iq u e ( C la r k and E v a n s , 1 9 5 4 ) w as a p p lie d .
The
s ta n d a rd v a r ia t e of th e n o r m a l c u rv e (c) p ro v id e s a te s t of s ig n ific a n c e
f o r d e v ia tio n s f r o m e x p e c te d r a tio s o f o b s e rv e d /e x p e c te d m e a n d is ­
ta n c e s to n e a re s t n e ig h b o r (R ) (T a b le 6 ).
te n d e n c y to w a rd u n ifo rm d is p e rs io n .
T h e r e a p p e a rs to be s o m e
F ig u r e 8 in d ic a te s th a t the
d e v ia tio n o f R v a lu e s f r o m p e r f e c t ran d o m n e s s (R = 1. 00) o c c u rs in
both d ir e c tio n s .
F iv e R v a lu e s a r e u n d e r 1 .0 0 ,
fo u r a r e o v e r .
Of
c o u rs e , th e r e is an in e q u a lity in th e d e v ia tio n f r o m ran d o m n e s s ; th e
v a lu e s O ver 1 .0 0 a r e l a r g e r .
F ig u r e 9 show s th e change o f c w ith t im e .
In the f i r s t h a lf
(J u ly 2 8 -S e p te m b e r 19) o f th e p a r t of th e y e a r c o v e re d b y the census
s e r ie s (c o m b in in g 1970 and 1971 d a ta ), no d is p e rs io n s w e r e s ig n if i­
c a n tly n o n ra n d o m .
In th e second h a lf (S e p te m b e r 2 0 -N o v e m b e r 12),
th e r e w e r e one ra n d o m and th r e e u n ifo r m d is p e rs io n s .
A F is h e r
E x a c t P r o b a b ilit y te s t sho w ed th a t th e s e tw o p ro p o rtio n s a r e s ig n if i­
c a n tly d if f e r e n t (®^ - 0 . 0 5 ) .
T h e s e d a ta su g g est th a t u n ifo r m ity m a y
in c r e a s e in th e f a l l .
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
33
T A B L E 6.
M e a s u re m e n t o f th e D is p e r s io n of B e a rs
on N o rth T w in Is la n d , 1970 and 1 971,
f r o m A e r i a l C en su ses
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to n e a re s t n e ig h b o r.
■L^
S ta n d a rd v a r ia t e o f n o r m a l c u rv e .
*^1 p e r cen t s ig n ific a n c e le v e l.
^5 p e r c e n t s ig n ific a n c e le v e l.
T h e d is p e r s io n of th e p o p u la tio n does not s e e m to v a r y w ith
its sex c o m p o s itio n .
p e rs e d ,
F o r th e p o p u la tio n s d e c la r e d u n ifo r m ly d is ­
th e m e a n p e rc e n ta g e of lo n e b e a r s w as 53 p e r cent; f o r
th e ra n d o m p o p u la tio n s ,
th e m e a n p e rc e n ta g e of lo n e b e a r s w as
48 p e r c e n t.
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1.3
1 .1—
0 .9 —
0 .7
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34
AUGUST
13 15
SEPTEMBER
3
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33
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OCTOBER
DATE
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13
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26
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22
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DATE
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NOVEMBER
36
T h e p o s s ib ility th a t th e u n ifo r m a s p e c t of th e d is p e rs io n s w as
c re a te d b y f a m ilie s w h ic h w e r e m a in ta in in g a m in im u m d is ta n c e fr o m
lo n e b e a r s , w h ile s in g le s w e r e a rr a n g e d ra n d o m ly w ith re s p e c t to
each o th e r, does not s e e m to a p p ly .
T h e m e a n d is ta n c e , f o r a l l th e
c e n s u s e s, f r o m a f a m ily to its n e a r e s t lo n e n e ig h b o r, w as 1. 32 m ile s .
T h e m e a n d is ta n c e f r o m a lo n e b e a r to its n e a re s t lo n e n e ig h b o r w as
1 .1 5 m ile s .
A z - t e s t show ed th a t th e s e tw o m ean s w e r e not s ig n if i­
c a n tly d iffe r e n t
= 0. 0 5 ).
T h e lo c a tio n s of a l l b e a r s seen in 1970 and 1971 d u rin g a e r i a l
s u rv e y s a r e show n in F ig s . 10 and 1 1 , r e s p e c tiv e ly .
f r o m th e s e tw o m ap s a r e c o m b in e d in F ig . 12,
T h e lo c a tio n s
T h e s e fig u re s show
c e r ta in a re a s of c o n s is te n t o c c u p a tio n , such as th e r id g e n e a r th e
s o u th e rn tip of th e is la n d .
In o r d e r to d e te rm in e w h e th e r the
n o rth e rn and s o u th e rn h a lv e s o f th e is la n d w e r e e q u a lly u tiliz e d , a
c h i-s q u a re te s t w a s a p p lie d to th e p r o p o r tio n o f b e a r s in each h a lf as
shown in F ig s . 10 and 11.
N o s ig n ific a n t d iffe r e n c e w as d e te c te d .
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
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X
CHAPTER
V
D IS C U S S IO N
A n n u a l M o v e m e n ts
B e fo r e d is c u s s in g th e fa te of m a r k e d b e a r s , e s p e c ia lly those
seen in 1970 but not in 1 9 7 1 , th e p o s s ib ility th a t e a r tags p u lle d out o r
b e c a m e c o v e re d b y f u r m u s t be c o n s id e re d .
M y e x p e rie n c e in o th e r
b e a r ta g g in g p r o g r a m s shôw ed th a t bo th events can o c c a s io n a lly
o c c u r so th a t c a p tu re d b e a r s cannot be re c o g n iz e d as m a rk e d ones
u n til t h e ir e a rs a r e c a r e f u lly e x a m in e d .
B y th is s ta n d a rd I ju d g e th a t
o n ly one o r tw o o f th e b e a r s w h ic h w e r e not re s ig h te d on N o rth T w in
Is la n d w o u ld h a v e b e e n u n re c o g n iz a b le in 1 9 7 1 .
P o la r b e a r s a r e r a r e l y r e p o r te d f r o m th e s o u th e rn and
e a s te r n coasts of J a m e s B a y ,
T h e r e f o r e , i f th e d is a p p e a ra n c e o f the
m a rk e d b e a rs is p a r t of a r e g u la r p a tte r n of m o v e m e n t, it is p ro b a b le
th a t in 1971 th e m a r k e d b e a r s m o v e d e ith e r n o rth , w ith the ic e
d r iftin g in to Hudson B a y , o r w e s t, to th e O n ta r io coast and th e n ce
in la n d .
T h e la t t e r is m o r e p ro b a b le th a n th e f o r m e r ; th e r e w e r e no
r e p o r ts of m a r k e d b e a r s s ig h te d o r k ille d on th e B e lc h e r Is la n d s .
Th o se is la n d s a r e th e m a in la n d m a s s th a t the b e a rs w ou ld d r if t to i f
th e y m o v e d n o rth w ith th e ic e .
T h e p la u s ib ilit y of m a rk e d b e a rs
40
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
41
m o v in g in la n d is in c r e a s e d b y o b s e rv a tio n s th a t p o la r b e a r s in
M a n ito b a c o m m o n ly spend th e hot s u m m e r m onths in dens n e a r
p e r m a f r o s t , m a n y m ile s in la n d f r o m H udson B a y (J o n k e l et a l . ,
1 9 7 2 ).
T h e s a m e s itu a tio n cou ld b e o c c u rr in g in O n ta rio .
T h e a p p a re n t d is c o n tin u ity o f use of N o r th T w in Is la n d b y
in d iv id u a l b e a r s suggests th a t th e s e b e a r s a r e a p o rtio n of a p o p u la ­
tio n w h ic h is s p re a d o v e r a n a r e a c o n s id e ra b ly l a r g e r th an th e
e n v iro n s o f th e T w in Is la n d s .
T h is c o n c lu s io n is s u p p o rte d b y th e
v a r i a b i l i t y in a g e -s e x s t r u c t u r e on th e is la n d b e tw e e n y e a r s .
b e a r s do not s e e m to le a v e J a m e s B a y .
These
B e a rs m a r k e d in J a m e s B a y
h a v e not b e e n s ig h te d o u ts id e i t (C . J o n k e l, p e r s . c o m m . ).
Con­
v e r s e ly , b e a r s m a r k e d in H udson B a y h ave not b e e n seen in J a m e s
B ay.
F o r t y p e r cen t o f th e b e a r s m a r k e d in th e S o u th e rn Hudson B a y -
J a m e s B a y re g io n w e r e a c tu a lly o u tsid e J a m e s B a y n e a r W in is k and
C a p e H e n r ie tta M a r i a .
T h u s , th e p o p u la tio n to w h ic h th e N o r th T w in
Is la n d b e a r s b e lo n g a p p a re n tly is r e s t r ic t e d to th e g e n e ra l a r e a of
Jam es B ay.
A c t iv it y P a tte r n s
D a ta c o n c e rn in g a c t iv it y p a tte rn s and food h a b its of b e a r s on
N o r th T w in Is la n d in d ic a te th a t th e y do l i t t l e fe e d in g and r e s t m o s t o f
th e t im e .
C o m p a ra b le p e rio d s of fo o d s h o rta g e a r e s u c c e s s fu lly
o v e rc o m e b y b la c k and g r i z z l y b e a r s d u rin g w in t e r .
B e fo r e it can b e
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42
s ta te d c o n fid e n tly th a t r e s tin g is th e p r i m a r y a c t iv it y o f p o la r b e a r s
on th e is la n d d u rin g i c e - f r e e m o n th s, d a ta should be g a th e re d on th e
a c tiv it ie s o f th e b e a r s d u rin g d a rk n e s s .
A lth o u g h th e la c k o f tr a c k s
in th e " la te f a l l in d ic a te d th a t b e a r s w e r e not t r a v e lin g and fe e d in g at
n ig h t d u rin g th a t t im e o f y e a r , th is m ig h t not be th e case in s u m m e r .
T h e r m o r e g u la tio n m a y a ffe c t a c tiv it y p a tte rn s of th e b e a rs
in s u m m e r .
R e s tin g cou ld be im p o s e d b y th e h e a t w h ic h fo ra g in g
w o u ld g e n e ra te .
T h e ir r e s tin g lo c a tio n s c o u ld a ls o be in flu e n c e d b y
th e e x p o s u re o f d if f e r e n t s ite s to c o o lin g w in d s .
D is p e r s io n
T h e c o n c e n tra tio n o f b e a r s on N o r th T w in Is la n d poses a
q u e s tio n (in fa c t a q u e s tio n w h ic h w as re c o g n iz e d a t th e b eg in n in g of
th is s tu d y ) c o n c e rn in g w h a t fa c to r s g e n e ra te th e d is p ro p o rtio n a te ly
la r g e p o p u la tio n of p o la r b e a r s on th e is la n d .
A n u m b e r o f e x p la n a ­
tio n s can b e p re s e n te d to acco u n t f o r th e p re s e n c e of b e a r s in c e n t r a l
Jam es B ay.
T h e m o s t l i k e l y f a c t o r is th e a v a ila b ilit y of f ir e a r m s in
th e J a m e s B a y a r e a s in c e th e fo u n d in g o f th e H u d so n 's B a y C o m p a n y
in 1 6 7 0 .
F o r 3 0 0 y e a r s , th e r e has p r o b a b ly b ee n a s e le c tiv e a d v a n ­
ta g e f o r b e a r s th a t r e m a in e d in th e c e n te r o f th e b a y d u rin g s u m m e r
and f a l l , in s te a d of on th e m a in la n d c o a s t.
T h e r e is c o n s id e ra b le
t r a f f i c b e tw e e n s e ttle m e n ts b y n a tiv e h u n te rs , b u t th e y r a r e l y ta k e
cano es to th e is la n d s in th e c e n te r of th e b a y .
T h is s t i l l does
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43
not e x p la in th e c o n c e n tra tio n o f b e a r s on ju s t N o r th T w in Is la n d .
C r i t i c a l r e s o u r c e s th a t w o u ld a t t r a c t p o la r b e a r s d id not
s e e m to e x is t e x c lu s iv e ly on N o r th T w in Is la n d .
T h e b e a r s on th e
is la n d w e r e not e x p lo itin g a n y m a jo r food s u p p ly .
N o s o c ia l a g g r e ­
g a tio n s w h ic h c o u ld in flu e n c e fu tu r e h u n tin g o r m a tin g w e r e d e te c te d .
T h u s , th e re a s o n f o r th e abundance of b e a r s on th e is la n d r e m a in s
o b s c u re .
P o s s ib ly , th e g r a d u a l a d o p tio n o f a u n ifo r m d is p e rs io n b y
th e p o p u la tio n d e m o n s tra te s th e t im e r e q u ir e d b y a p o p u la tio n to
b e c o m e s u ffic ie n tly f a m i l i a r w ith t h e ir lo c a le and t h e ir c o n s p e c ific s
to change f r o m ra n d o m to u n ifo r m d is p e rs io n .
A lt e r n a t iv e ly , th e
chan gin g d is p e rs io n cou ld be a fu n c tio n o f d e n s ity ; p o la r b e a r s m ig h t
b e c o n scio u s o f t h e ir r e la tio n s h ip s in sp ace w ith re s p e c t to one
a n o th e r a t d e n s itie s o f a p p r o x im a te ly 20 p e r 50 s q u a re m ile s , b u t
not a t d e n s itie s b e lo w th a t.
M o r e r e s e a r c h is r e q u ir e d to d e te r m in e th e e c o lo g ic a l
s ig n ific a n c e o f p o la r b e a r s p a c in g and d is p e rs io n .
I t s e e m s p ro b a b le
th a t in fo r m a tio n on th e d is p e rs io n o f p o la r b e a r s m ig h t in d ic a te th e
e c o lo g ic a l s itu a tio n of th e p o p u la tio n .
I f th is sho uld p ro v e t r u e , th e n
s u r v e y flig h ts cou ld b e flo w n o v e r a n u m b e r of a re a s w ith in th e
ra n g e of th e s p e c ie s .
D if f e r e n t s p a c in g p a tte rn s w o u ld p ro b a b ly
r e f l e c t d iffe r e n t s e le c tiv e p r e s s u r e s a c tin g on p o p u la tio n s .
The
la b ile n a tu r e of s o c ia l p a tte rn s and d is p e rs io n s o f p o p u la tio n s has
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
44
b e e n d e m o n s tra te d f o r s e v e r a l s p e c ie s (B ro w n and O r ia n s , 1970;
C r o o k , 1965 and 1970; O r ia n s , 1 9 6 1 ).
A p p e n d ix I I I d e s c rib e s how
th e c o a s tlin e f r o m N o r th T w in Is la n d to C h u r c h ill w as cens used and
an a g g re g a te d d is p e rs io n fou nd .
T h e d iffe r e n c e b e tw e e n d is p e rs io n
on N o r th T w in Is la n d and th e c o a s t suggests p o s s ib le m a jo r e c o lo g ic a l
d iffe r e n c e s in th e tw o p o p u la tio n s .
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
CHAPTER
VI
SUMMARY
T h e e c o lo g y of p o la r b e a r s on N o r th T w in Is la n d , N o rth w e s t
T e r r i t o r i e s , J a m e s B a y w as s tu d ie d d u rin g s u m m e rs and f a lls f o r
3 y e a rs .
T e c h n iq u e s used to g a th e r d a ta in v o lv e d o b s e rv a tio n f r o m
th e g ro u n d , a e r i a l c e n s u s e s , and c a p tu rin g and m a r k in g in d iv id u a l
b e a rs .
B e a rs w e r e m a r k e d w ith e a r ta g s and dye a f t e r b ein g c a p tu re d
in a fo o t s n a re and im m o b iliz e d w ith p h e n c y c lid e n e h y d ro c h lo rid e .
G ro u n d o b s e rv a tio n s show ed th a t bo th lo n e b e a rs and f a m ilie s
s p e n t m o s t o f t h e i r t im e r e s tin g w h ile on th e is la n d .
s e ld o m o b s e rv e d ;
F e e d in g w as
w h e n fe e d in g d id o c c u r, th e m a in foods w e r e
c r o w b e r r ie s and C a n a d a g e e s e .
A e r i a l censu ses in d ic a te d th a t th e p o p u la tio n on th e is la n d
in c r e a s e d g r a d u a lly d u rin g th e i c e - f r e e seaso n (J u ly to N o v e m b e r).
N in e a e r i a l censuses d e m o n s tra te d ra n d o m d is p e rs io n s of b e a r s on
th e is la n d on s ix o c c a s io n s and u n ifo r m d is p e rs io n s on th r e e .
The
re a s o n f o r th e change f r o m ra n d o m to u n ifo r m d is p e rs io n s w a s u n d e ­
t e r m in e d .
T h e a e r i a l cen su ses a ls o show ed th a t in 1 970, th e r e w e r e
a t le a s t 40 b e a rs on th e is la n d and in 1 9 7 1 , th e r e w e r e at le a s t 2 2 .
S o m e b e a r s m a r k e d b y th e C a n a d ia n W ild lif e S e r v ic e w e r e o b s e rv e d
45
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46
on th e is la n d .
O b s e rv a tio n s of 17 tagged b e a r s in 1970 in d ic a te d th a t
b e a r s re m a in e d on th e is la n d th ro u g h th e i c e - f r e e seaso n once th e y
a r r i v e d th e r e .
F a i l u r e to r e s ig h t m a r k e d b e a r s on N o r th T w in Is la n d in 1971
s u g g ested th a t th e r e is no d is c r e te p o p u la tio n o f p o la r b e a r s r e tu r n in g
to th e is la n d each y e a r .
E v id e n tly a p o p u la tio n of p o la r b e a rs ra n g e s
o v e r th e J a m e s B a y a r e a and e v e r y y e a r s o m e p e rc e n ta g e of th a t
p o p u la tio n spends th e s u m m e r and f a l l on is la n d s in th e B a y , p r i ­
m a r i l y N o r th T w in Is la n d .
T h e p re s e n c e of f ir e a r m s in th e J a m e s
B a y a r e a f o r 300 y e a r s has a p p a re n tly p ro d u c e d , f o r p o la r b e a r s , a
s e le c tiv e ad van tag e in r e m a in in g on is la n d s d u rin g th e i c e - f r e e season ,
th e r e b y a v o id in g h u n te rs alo n g th e c o a st.
T h e o v e r a ll r o le o f N o r th T w in Is la n d in th e e c o lo g y of p o la r
b e a rs in J a m e s B a y t h e r e f o r e s e e m s to be an a r e a o f s e c lu s io n in
w h ic h to r e s t d u rin g s u m m e r and f a l l w hen food is r e la t iv e ly s c a r c e .
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
L IT E R A T U R E
C IT E D
B e a ls , C . S . , and D . A . Shenstone (E d s . ). 1 9 6 8 . S c ie n c e , h is to r y ,
and Hudson B a y , V o l. I . In fo r m a tio n C a n a d a , O tta w a .
501 pp.
B ro w n , J . L . , and G . H . O r ia n s . 1 9 7 0 . Spacing p a tte rn s in m o b ile
a n im a ls . P p . 2 3 9 -2 6 2 in: R . F . Johnston (E d . ). A n n u a l
r e v ie w o f e c o lo g y and s y s te m a tic s . V o l. I.
C l a r k , P . J . , and F . C . E v a n s . 1954. D is ta n c e to n e a r e s t n e ig h b o r
as a m e a s u r e of s p a tia l r e la tio n s h ip s in p o p u la tio n s . E c o lo g y
3 5 :4 4 5 -4 5 3 .
C r a ig h e a d , F . C . , J r . , and J. J . C ra ig h e a d . 19 6 5 .
g r i z z l y b e a r s . B io S c ie n c e 1 5 (2 ):8 8 -9 2 .
T r a c k in g
C r a ig h e a d , J , J . , M . H o rn o c k e r, W . W o o d g e rd , and F . C .
C r a ig h e a d , J r . 1 9 60 . T ra p p in g , im m o b iliz in g and c o lo r m a r k in g g r i z z l y b e a r s . T r a n s . N . A m . W ild l. C o n f. 25:
3 4 7 -3 6 3 .
C r o o k , J . H. 1 9 6 5 . T h e a d a p tiv e s ig n ific a n c e o f a v ia n s o c ia l o r g a n i­
z a tio n s . S ym p . Z o o l. Soc. L o n d . 14:181 -2 1 8 .
1 9 7 0 , S o c ia l o r g a n iz a tio n and th e e n v iro n m e n t: a s p e c ts of
c o n te m p o ra r y s o c ia l e th o lo g y . A n im . B e h a v . 1 8 :1 9 7 -2 0 9 .
H a rin g to n , C . R . 1 9 6 1 . Som e d ata on th e p o la r b e a r and its u t i l i z a ­
tio n in th e C a n a d ia n A r c t ic . U n p u b l. R p t . , C a n a d ia n W ild l.
S e rv . , O tta w a . 33 p p .
J o n k e l, C . J . 1 9 6 7 . L i f e h is t o r y , e c o lo g y , and b io lo g y of th e p o la r
b e a r , a u tu m n 1966 s tu d ie s . C a n . W ild l. S e rv . P r o g . N o te s
1. 8 pp.
_
, and I . M c T . C o w a n . 19 71. T h e b la c k b e a r in th e s p r u c e f i r fo r e s t. W il d l . M o n o g . 2 7 . 57 pp.
47
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
48
___________ G . B . K o le n o s k y , R . J. R o b e rts o n , and R . H . R u s s e ll.
1 9 7 2 . F u r t h e r notes on p o la r b e a r denning h a b its . P p . 1 4 2 158 in: B e a r s , T h e ir B io lo g y and M a n a g e m e n t. In te r n a tio n a l
U n io n f o r the C o n s e rv a tio n of N a tu r e P u b lic a tio n s , New
S e r ie s , M o r g e s , S w itz e rla n d 2 3 .
371 pp.
L a r s e n , T . 1 9 6 7 . T h e tra p p in g and study of p o la r b e a r s , S p its b e rg e n ,
1 9 6 6 . P o la r R e c . 1 3 (8 6 ):5 8 9 -5 9 3 .
L e n t f e r , J . W . 1 9 6 8 . A te ch n iq u e f o r im m o b iliz in g and m a r k in g
p o la r b e a r s . J. W ild l. M g m t. 3 2 {2 ):3 1 7 -3 2 1 .
M a n s fie ld , A . W . 1 967. S eals of a r c t ic and e a s te rn C an ad a.
F is h e r ie s R e s e a rc h B o a rd o f C an ad a B u ll. N o . 137. 35 pp.
O r ia n s , G . H . 1 9 6 1 . T h e e c o lo g y o f b la c k b ir d (A g e la iu s ) s o c ia l
s y s te m s . E c o l. M o n o g . 3 1 (3 ):2 8 5 -3 1 2 .
R u s s e ll, R . H. 1971. S u m m e r and a u tu m n food h a b its of is la n d and
m a in la n d p o p u la tio n s of p o la r b e a r s - - a c o m p a ra tiv e study.
U n p u b l. M . Sc. th e s is , U . of A lb e r t a , E d m o n to n . 87 pp.
T r o y e r , W . A . , and R . J . H e n s e l. 1 9 6 1 . S tru c tu re and d is tr ib u tio n
of a K o d ia k b e a r p o p u la tio n . J . W ild l. M g m t. 2 8 (4 ):7 6 9 772.
U n ite d States G o v e rn m e n t. 1 9 6 6 . P ro c e e d in g s of th e F i r s t I n t e r ­
n a tio n a l S c ie n tific M e e tin g on th e P o la r B e a r , F a ir b a n k s ,
A la s k a , S e p te m b e r 6 - 1 0 , 1 9 6 5 .
v i i i + 72 pp. (P u b lis h e d
jo in t ly w ith th e U . o f A la s k a . )
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
A P P E N D IX
I
K O L M O G O R O V -S M IR N O V
A N A L Y S IS
O F A C T IV IT Y P A T T E R N S
D a ta w e r e a s s e m b le d to u t iliz e as m u c h a v a ila b le in fo r m a tio n
as p o s s ib le .
F o r e a c h o b s e rv a tio n a l p e r io d , th e p r o p o r tio n of t im e
d evo ted to th r e e c a te g o r ie s of b e h a v io r (fe e d in g , tr a v e lin g , and
r e s tin g ) w a s r e c o rd e d .
F re q u e n c y d is trib u tio n s (A p p . la , Ib , and
Ic ) w e r e m a d e o f th e s e d a ta and m o d ifie d in to c u m u la tiv e fre q u e n c y
d is tr ib u tio n s (A p p . Id , le , and I f ) to a llo w th e a p p lic a tio n of the
K o lm o g o ro v S m irn o v t e s t .
B e c a u s e th e s a m p le s iz e s w e r e le s s th a n 40 (n^ = 2 9, ri 2 = 10 ),
th e c h i-s q u a r e a p p ro x im a tio n w as used (S ie g e l, S.
p a r a m e t r ic S ta tis tic s .
M c G r a w -H ill, New Y o rk .
1956,
Non-
312 p p .) .
T h is
m o d ific a tio n of th e K o lm o g o r o v -S m ir n o v te s t is b a s e d on th e fa c t
th a t th e s a m p lin g d is t r ib u t io n o f
2
„
(n in 2 )
(ni + ng)
is a p p ro x im a te d b y th e c h i- s q u a r e d is tr ib u tio n w ith 2 d e g re e s of
fr e e d o m ,
w h e re n^ and n^ a r e s a m p le and D is th e s ta n d a rd
49
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
50
K o lm o g o r o v -S m irn o v q u a n tity m e a s u rin g th e d iffe r e n c e b e tw e e n th e
tw o m o s t d iffe r e n t c u m u la tiv e p r o p o r tio n a l fre q u e n c ie s f o r th e s a m e
c la s s (A p p , Id , le , and I f ) .
T h o s e th r e e ta b le s a ls o show the c o m ­
p a r is o n of th e re s p e c tiv e c u m u la tiv e fre q u e n c y d is trib u tio n s , the
d e te r m in a tio n of th e th r e e v a lu e s o f D , and th e c a lc u la tio n of th e th r e e
c h i-s q u a r e s .
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
24—
20—
18—
>u
16—
Z
aUl
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12 —
lO
4—
0 .0 - 0 .0 110.0- 19.obO.O-29.0 3O .O -39.0 I4O1O - 4 9 .9I 5OJO- S 9.o j6 0.0-60.0 70 .0 -7 9 .0 1 8 0 .0 -8 9 .0 0 0 0 - 1 0 0
PERCENTAGE
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98"
34—
33—
30—
18—
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3
14-
a
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jrVvyi
| 7 0 - 7 9 | 8 0 - 89 | 9 0 - 100
PERCENTAGE
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78—
26-
74—
77—
70-
18-
>-
u
2
Ul
3
a
12-
10—«
4—
0 - 9
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I 4 0 - 4 9 I SO - 5 0
| 6 0 - 6 9 | 7 0 - 7 9 18 0 - 8 0
PERCENTAGE
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9 0 -lO O l
CD
■D
O
Q.
C
g
Q.
■CDD
A P P E N D IX Id .
C/)
Cumulative Frequency Distributions fo r the Percentage of each Observational Period
Spent Resting, F am ilies and Lone Bears
o'
3
O
,
8
(O '
0.09 .9
1 0 .0 19.9
20.02 9 .9
3 0 .0 39.9
40.04 9 .9
5 0 .0 59.9
60.069.9
7 0 .0 79.9
8 0 .0 89.9
Cumulative
Frequency
4
4
5
5
6
7
8
9
Cumulative
Proportional
Frequency
0.138
0.138
0.172
0.172
0.206
0.241
0.285
0.310
0.414
Cumulative
Frequency
2
2
2
2
2
3
3
3
5
Cumulative
Proportional
Frequency
0.200
0.200
0.200
0.200
0.200
0.300
0. 300
0.300
0. 500
12
% .o 100.0
29
Lone Bears
3.
3
"
CD
CD
■D
O
Q.
C
a
o
3
■D
O
CD
Q.
1.000
10
F a m ilie s
1.000
■CDD
C/)
C/)
tn
CD
■D
O
Q.
C
g
Q.
■CDD
A P P E N D IX le .
C/)
W
o'
3
0
3
Cumulative Frequency Distributions fo r the Percentage of each Observational Period
Spent Traveling, Fam ilies and Lone Bears
0.09.9
CD
8
Cumulative
Frequency
ci'
3"
1
3
CD
19
1 0 .0 19.9
22
20.02 9 .9
22
30.039.9
23
40.049.9
23
50 .0 59.9
24
6 0 .0 69.9
24
70 .0 79.9
24
80.089.9
25
90 .0100.0
29
Lone Bears
"n
c
3.
3
"
CD
Cumulative
Proportional
Frequency
0.655
0.759
0.759
0.793
0.793
0.828
0.828
0.828
0.862
Cumulative
Frequency
8
8
8
9
9
9
9
9
9
Cumulative
P roportional
Frequency
0.800
0.800
0.800
0. 900
0.900
0. 900
0. 900
0.900
0.900
1.000
CD
■D
O
Q.
C
a
O
3
■D
O
CD
Q.
10
F a m ilie s
1.000
■CDD
C/)
C/)
Ul
Ul
CD
■D
O
Q .
C
g
Q .
■O
?
w
A P P E N D IX I f .
Cumulative Frequency Distributions for the Percentage of each Observational Period
Spent Feeding, F am ilies and Lone Bears
o'
3
0
3
CD
0.09.9
8
10.019. 9
20.02 9 .9
30.039.9
40.049.9
5 0 .0 59.9
60.069. 9
7 0 .0 79.9
8 0 .0 89. 9
90.0100.0
(O '
3"
Cumulative
Frequency
1
3
26
28
29
29
29
29
CD
"n
"
CD
■CDD
O
Q.
C
a
o
3
CD
Q.
29
29
29
Lone Bears
c
3.
3
■D
O
29
Cumulative
Proportional
Frequency
0.897
0.965
1.000
1.000
1.000
1.000
1.000
1.000
1.000
Cumulative
Frequency
7
9
9
9
9
9
9
9
9
Cumulative
Proportional
Frequency
0.700
0. 900
0. 900
0. 900
0. 900
0.900
0. 900
0. 900
0. 900
1.000
10
F a m ilie s
1.000
■CDD
C/)
cn
05
A P P E N D IX
MAPS
S H O W IN G
ON
THE
NORTH
II
D IS P E R S IO N
T W IN
OF
BEARS
IS L A N D
T h e fo llo w in g m ap s show th e lo c a tio n s o f b e a r s on N o rth
T w in Is la n d as d e te rm in e d b y a e r i a l censuses on n in e occasio ns in
1970 and 1 9 7 1 .
O n each o f th e m ap s th e fo llo w in g s y m b o ls a r e used:
O - f a m ily
•
= lo n e b e a r
57
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
t
5
r
%
I m il#
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
5
1
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ride*
b l^ h
p Q ln t
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X
%%
%
« mira
r#dg«
h ifh
p o in t
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X
t
LJüUfl
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%
i
%
m
»mil*
r*a##
hl#h
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X
5
5
4'
A
1mit#
fW#*
blah
paint
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X
11
%
I .ml4*
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
I
%
§
Irn y e
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
I
5
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»
1
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
A P P E N D IX
D IS P E R S IO N
OF
POLAR
ni
BEARS
ALONG
THE
SO U TH W E S TE R N CO AST O F HUDSON B A Y
O n O c to b e r 3 and 5, 1 9 7 1 , tw o p ilo ts and tw o o b s e rv e rs
con du cted an a e r i a l census o f th e s o u th w e s te rn c o a s t o f H udson B a y in
a tw in -e n g in e a i r c r a f t ( D C - 3 ) f ly in g a t an a ltitu d e of 2 5 0 -3 0 0 fe e t.
T h ro u g h o u t th e f lig h t , th e g ro u n d speed (v a r y in g b e tw e e n 120 and 140
k n o ts ) and t im e (to th e n e a r e s t h a lf m in u te ) o f s ig h tin g f o r e a ch b e a r
w e r e n o ted .
D is ta n c e b e tw e e n b e a r s w as th e n c a lc u la te d f o r a l l b e a r s
s ig h te d a lo n g th e 806 m ile s of c o a s t.
D is ta n c e s u n d e r 1 m i l e w e r e
e s tim a te d v is u a lly f r o m th e a i r c r a f t to th e n e a r e s t q u a r t e r m ile .
s ig h te d b e a r s w e r e o b s e rv e d w ith b in o c u la rs f o r e a r ta g s .
A ll
The
p r i m a r y o b je c tiv e o f th e f lig h t w as to lo c a te a n im a ls m a r k e d in 1970
on N o r th T w in Is la n d .
S in c e m o s t of th o s e b e a r s w e r e sow s and cubs
in 1 9 7 0 , sow s w ith y e a r lin g s w e r e c h e c k e d m o r e c a r e f u lly th a n lo n e
a n im a ls .
A to t a l of 167 b e a r s w e r e s e e n .
A s in th e a n a ly s is o f th e
d is p e rs io n of b e a r s on N o r th T w in Is la n d , e a ch f a m i l y w as t r e a t e d
a s i f i t w e r e a s in g le b e a r , w ith th e r e s u lt th a t o n ly 142 p o in ts w e r e
c o n s id e re d .
R. H.
1957.
B y u t iliz in g th e f o r m u la w h ic h M a c A r t h u r ( M a c A r t h u r ,
O n th e r e la t iv e abundance of b ir d s p e c ie s .
67
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
P r o c . N a t.
68
A c a d . S o i. 4 5 :2 9 3 -2 9 5 . ) used to g e n e ra te h is b r o k e n -s t ic k m o d e l f o r
s p e c ie s abu nd ance, in w h ic h a u n it le n g th lin e is b r o k e n in to ra n d o m
le n g th s e g m e n ts and th e le n g th o f th e r * ^ s h o rte s t s e g m e n t is
w h e r e n = th e to ta l n u m b e r of s e g m e n ts , a r a n d o m ly d is p e rs e d p o p u ­
la tio n o f b e a r s a lo n g th e c o a s tlin e c o u ld b e s im u la te d .
T h e w h o le
fu n c tio n w a s m u ltip lie d b y 8 0 6 . 2 5 to expand th e lin e f r o m u n it le n g th
to th e le n g th of th e c o a s tlin e .
T h e n u m b e r of s e g m e n ts (n) w a s s e t a t
142.
A c o m p u te r p r o g r a m w as w r it t e n w h ic h c a r r i e d out th e 142
r e p e titio n s of th e c a lc u la tio n and t h e r e f o r e p ro d u c e d a ra n k e d s e r ie s
o f 142 d is ta n c e s to n e a r e s t n e ig h b o r f o r a ra n d o m d is p e r s io n a lo n g a
lin e .
A c o m p a ris o n o f o b s e rv e d and ra n d o m d is p e rs io n s w a s m a d e
b y r a n k in g th e d is ta n c e s to n e a r e s t n e ig h b o r f o r th e 142 o b s e rv e d
p o in ts (A pp . I l i a ) .
(M a c A rth u r, R . H .
A m e r . N a t.
T h e c u s to m a r y lo g a r it h m ic a r r a n g e m e n t
1960.
9 4 :2 5 -3 6 ;
and r a r i t y , of s p e c ie s .
O n th e r e la t iv e ab u n d an ce o f s p e c ie s .
P r e s to n , F . W .
1948.
The com m onness,
E c o l. 2 9 : 2 5 4 - 2 8 3 .) w a s u s e d , in w h ic h th e
d a ta w e r e p re s e n te d in o c ta v e s in s te a d of a r it h m e t ic in t e r v a ls .
E x a m in a tio n o f th e "O” c o lu m n of A p p . I l l a show s th a t, in
th e o b s e rv e d fre q u e n c y d is t r ib u t io n , b e a r s w e r e a g g re g a te d ; th e r e
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
69
w e r e m a n y m o r e b e a r s le s s th a n o n e -fo u r th m ile f r o m t h e ir n e a r e s t
n e ig h b o r (5 7 ) th a n th e r e w e r e in th e ra n d o m fre q u e n c y d is tr ib u tio n (3 ).
T h is in fo r m a tio n is a q u a n tita tiv e c o n fir m a tio n o f r e p o r ts (C . J o n k e l
and D . C r o s s , p e r s . c o m m . ) of grou ps of b e a r s a lo n g th is c o a s tlin e .
O b s e rv a tio n s m a d e on th is f lig h t a ls o c o rre s p o n d e d w ith e a r l i e r
r e p o r ts in th a t th e s e g ro u p s o c c u rr e d p r i m a r i l y on capes and s m a ll
sand is la n d s .
A P P E N D IX I l i a .
T h e F r e q u e n c ie s of D is ta n c e s to N e a r e s t N e ig h b o r
f o r an O b s e rv e d P o p u la tio n of P o la r B e a r s on th e H udson B a y C o a s t
and a R a n d o m ly D is p e r s e d H y p o th e tic a l P o p u la tio n
O c ta v e (D is ta n c e to N e a r e s t B e a r in M ile s )
0
i
i
1
2
4
O b s e rv e d F re q u e n c y
57
7
11
18
27.5
12.5
E x p e c te d F re q u e n c y
3
6
8
16
25
34
8
16
32
4
1
15
2
4
33
T h e s ig n ific a n c e of th e s e g ro u p s is e n t ir e ly a m a t t e r of
s p e c u la tio n .
T h e g ro u p in g co u ld b e a r e s u lt o f th e lo c a liz a t io n of
s o m e im p o r ta n t f a c t o r s u ch as fr e e d o m f r o m in s e c ts , th e p r e s e n c e of
k e lp o r sea du cks, c o o lin g f r o m s o m e deep w a t e r a s h o rt d is ta n c e
o ffs h o re , o r b e a c h in g p o in ts f o r w h a le o r s e a l c a rc a s s e s .
A lte r n a ­
t iv e ly , the group cou ld have a fu n c tio n in d e p e n d e n t o f lo c a tio n ;
r e la tio n s h ip s
could b e e s ta b lis h e d w h ic h m ig h t in flu e n c e m a tin g o r
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
70
h u n tin g su c c e s s in th e w in te r s and s p rin g s .
T h e o n ly s o lu tio n to
th e s e p r o b le m s is in te n s iv e o b s e rv a tio n o f th e g ro u p s ,
ta s k .
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
a d if f ic u lt