185
A erial surveys of G reater W hite-fro nted
Geese Anser a lbifrons frontalis and
other w a te rfo w l in the Rasmussen Lowlands
of the Central Canadian Arctic
J . E. H ines, M . F. Kay1 & M . O. Wiebe
Canadian Wildlife Service, Environment Canada, Suite 3 0 1, 5204 - 50th Avenue,
Yellowknife, Northwest Territories X1A 1E2, Canada.
Email: jim. hinesBec. gc. ca; myra. robertson0ec. gc.ca
'Present address: 68 Fair Oaks Drive, St. Albert, Alberta T8N 1R1, Canada.
H e licopter s u r v e y s w e r e c a r ried out in J u n e 1 9 9 4 -9 5 to d e t e r m i n e the
n u m b e r s and distrib ution of Gre a ter W h it e-fro nted G e e s e Anser a lbifrons
frontalis and o th e r w a t e r f o w l in the R a s m u s s e n L o w l a n d s of the C entra l
C a n a d i a n Arctic. The r e s u l t s provide info rm atio n n e eded for the m a n ­
a g e m e n t of G re a te r W h ite-fronted G e e s e a s w e l l a s fo r eva lu a tin g the
biolo gi cal i m p o r ta n c e of the R a s m u s s e n L o w l a n d s a s a potential ' p ro ­
tected a r e a '. E st im a t e d n u m b e r s of w a t e rfo w l in the 6, 2 6 5 k m 2 s u r v e y
area w e r e 42, 041 L e s s e r S n o w G e e s e Anser caerulescens caerulescens,
23, 516
G re a te r W h it e -fro n t e d
spectabilis, 6, 4 1 2
Canada
Geese,
13, 690
K in g
E id e r s Somateria
G e e s e Branta canadensis hutchinsii, 5, 427
L o n g -t a ile d D u c k s Clangula hyemaIis a nd 3, 8 22 T u n d ra S w a n s Cygnus
columbianus. S m a l l e r n u m b e r s of s e v e r a l o th e r s p e c i e s of a qu a tic and
te rre s t ria l bird s w e r e o b s e r v e d and m i n i m u m popula ti on e s t i m a t e s are
reported for t h o s e s p e c i e s a s well. N u m b e r s of L e s s e r S n o w , Gre ater
Wh it e-fronted and C a n a d a G e e s e have in c re a s e d s u b s t a n tia lly in the
R a s m u s s e n L o w l a n d s s in c e the m i d - 1 9 70s, but K in g E i d e r s and L o n g ­
tailed D u c k s have declined markedly. Th e r e s u lt s s u p p o r t pre vio u s fi nd­
i n g s that the R a s m u s s e n L o w l a n d s is a critical b re eding a n d s u m m e r
are a for Gre a ter W h ite-fronted G e e s e and o th er a r c t ic - n e s tin g w a t e r ­
fowl, and f u rt h e r s tr e n g t h e n the r e c o m m e n d a t i o n s that th is site s h o u l d
be protected.
Key Words: Greater W hite -fro n ted Goose, Canada Goose, Lesser Snow Goose, Tundra
Swan, King Eider, Long-tailed Duck, a e ria l surveys, Rasmussen Lowlands, Central
Canadian Arctic
© Wildfowl & Wetlands Trust
Wildfowl [2003] 54: 183-199
186 W aterfow l surveys in the Rasmussen Lowlands
T h e Arctic G o o s e Joint Ventu re (part
of
the
North
Am erica n
W a t e rfo w l
Ducks
C la n g u la
hye m a Iis and
many
s p e c i e s of s h o re bir d s. The fi n d in g s led
the
to the design a tio n of the R a s m u s s e n
Gre ate r W hite-fronted G o o s e A n s e r a lb ­
L o w l a n d s a s a W etland of Internat ional
Management
P la n )
identified
ifrons fro n ta lis (hereafter a ls o referred
Im p o r ta n c e ( R a m s a r site; I U C N 1987)
to a s W hite-fronted Goose) a s a priority
a nd a s a C a n a d i a n Wildlife Servic e Key
for res e a rch and monitoring , and rec­
M ig r a to ry Bird Habitat Site (Ale xander
ommended
et al. 1991). A s a result, the site h a s
a
'breed ing
ground'
a p p r o a c h for delineating and m o n i t o r ­
been identified a s a potential candidate
ing
for protection a s a N a t io n a l Wildlife
p o pulations
species
of
of
t h is
and
o th e r
arctic-nesting
(Anonym ous
of
The objective of the a u t h o r s ' stu dy
w a s to de t e rm in e the cu rrent n u m b e r s
a p p r o a c h req uires inform ation on the
and distribution of G re ate r W h it e - fro n t­
bre eding d istributio n s and n u m b e r s of
ed G e e s e and o th er waterfow l in the
g e e s e from different breeding a r e a s in
Lo w la n d s . The r e s u lts are intended to
to
routes
Management
A rea ( J o hn sto n et al. 2000).
W hite-fronted G e e s e following s u c h an
addition
1995).
geese
know ledge
and
Rasm ussen
of m ig r a t i o n
provide
in f o r m a t io n
needed
for the
w intering
a re a s.
Th e
m a n a g e m e n t of W hit e-fronted Geese,
Low lan d s
site
('the
and to help in evaluation of the biologi­
L o w la n d s ') h a s been identified a s one
ca l
of the m a j or breeding
L o w l a n d s in view of its p o s s ib le d e s i g ­
Central
Canadian
fronted
Geese
areas
A r c tic
(Allen
&
in the
for W h it e Hogg
The
Low lan ds
site
the
Rasm ussen
nation a s a N a tio n a l Wildlife Area.
Methods
was
to o r n i t h o l o g i s t s
of
1978;
B r o m l e y & S t e n h o u s e 1994-).
unknown
im portance
la rg ely
until the
m i d - 1 9 7 0 s w h e n e n v iro n m e n ta l stu d ie s
The
Rasm ussen
Low lan ds
site
(68°40'N, 93°00'W] is situated on the
( M c L a r e n et al. 1977; Z d a n & Bra ck ett
m ainland
1977; Allen & H o g g
Arctic (Figure 1). It is bordered by the
1978) w ere c o n ­
of
the
Central
Canadian
ducted in the are a to d e term ine the
e s c a r p m e n t of the W a g e r H i g h l a n d s to
potential i m p a c t s of a p ro p o s e d natural
the east a n d by the arctic c o a st to the
g a s pipeline, w hich w o uld have p a s s e d
west. The land is flat to gently rolling,
th ro u g h the m id dle of the Lo w la n ds.
with s o m e e s k e r s and rock outcrops.
T h e s e s t u d ie s identified the i m p orta n ce
M o s t of the region is poorly draine d and
of the area a s a nesting and m o ult in g
n u m e r o u s la k e s and p o n d s are p r e s ­
area for W h it e-fr onted Geese, T un dra
ent. The L o w l a n d s site is located about
Swans
Cygnus
c o lu m b ia n u s ,
9 0 0 k m nort h of the tree line n e a r the
Snow
Geese
Anser
c a e ru le s c e n s ,
Canada
c an a de nsis
h u tc h in s ii,
S o m a te ria
s p e c ta b ilis ,
Lesser
c a e ru le s c e n s
boundary
the
of
two
m ajor
warm er,
e c o l o g ic a l
Geese
B ra n ta
zones:
King
Eide rs
s o u t h e r n arctic and the colder, s p a r s e ­
w e l l- v e g e t a t e d
L o n g - t a il e d
ly-vegetated northern arctic (Ecolo gica l
W aterfow l surveys in the Rasmussen Lowlands 187
Figure 1. Locations of transects surveyed within three strata in the R a sm u sse n Lowlands in June 19941995.
S tratific atio n
W orking
S ed ge-d o m in a ted
Group
1996).
meadows
and
out at a time w h e n
were
ne sting
and,
m o s t waterfowl
thus,
widely d i s ­
m a r s h e s , w hich are tu ndra c o m m u n i ­
pe rse d a s breeding o r territorial pairs.
ties frequently us e d by g e e s e and oth er
Th e
m ig ra to ry birds in the C a n a d i a n Arctic,
straight transects in a float-equipped
are widely distributed th r o u g h o u t the
Bell 2 0 6 L helicopter at an altitude of 45 m
L o w l a n d s (Jo hn sto n ef al. 2000).
above gr ound and a ground speed of 80-
A e ria l s u r v e y s w e r e carr ie d out in
the L o w l a n d s from 2 0 - 2 4 J u n e
1994
s u rv e y p ro ce dure
involved flying
100km/hr. Tra n se cts wer e oriented in an
east-w est
manner
(appro xim ate ly at
and 2 0 - 2 5 J u n e 1995, following g e n e r ­
righ t
ally accepted p ro c e d u re s for breeding
spaced
ground
expected to s u p p o r t h i g h e r den sit ie s of
surveys
of
waterfowl
( A n o n y m o u s 1987; S m it h 1995), s p e c i f­
angles
at
to
5km
the
c o a stlin e)
in t e rv a l s
g e e s e ( M c L a r e n et al.
in
and
areas
1977; Alle n &
ically modified for he li copter s u r v e y s in
H o g g 1978; B r o m l e y & S t e n h o u s e 1994)
arctic C a n a d a ( H ine s et al. 2000; H in e s
and at 1 0 k m intervals in a r e a s of lower
& W ie b e 2004). S u r v e y s w e r e carried
expected densities. A l l t r a n s e c t s wer e
188 W aterfow l surveys in the Rasmussen Lowlands
divided
into
2km
segm ents,
which
se rv ed a s a b a s i s for recording data.
Unpredicta ble w e a t h e r conditions, a
diately s o u t h of the stu dy area to verify
that the s o u t h e r n
limit of the
w aterfow l d e n s it ie s
in the
high
Low lands
s h o r t a g e of aircraft and the high cost of
had been reached. T h is area w a s not
co n ductin g
included in the overall population e sti­
he li copte r s u r v e y s
meant
that the s u r v e y s could not be restricted
m a t e s for the L o w la nds.
to a specific time of day. M o s t t r a n s e c t s
L e s s e r S n o w G e e s e typically nest in
were surveyed w h e n w i n d s w ere le ss
large co lo n ie s and are not easily s u r ­
than 2 5 k m / h r a nd the ceiling w a s m ore
veyed u s i n g widely s p a c e d aeria l t r a n ­
than 150m, a s r e c o m m e n d e d by B utler
sects. Thu s, a s well a s counti ng the
et ai. (1987, 1988], T h e s e specifi catio ns
n u m b e r s of S n o w G e e s e on the r e g u la r
could not be met on s o m e t r a n s e c t s but
t r a n s e c t s (all n o n - b r e e d e r s in flo ck s of
it is believed that this did not sig n ifi­
three or more birds), total counts of nest­
ing S n o w Gee se were carried out by flying
cantly bias the results.
S u r v e y s w ere co n ducted with two
over colonies at a height of 230m and
observers, one s ea ted in the left front
counting all ge ese within 1km of each
seat and the o th er in the right rear
side of the helicopter. Transects were
seat, w hich w a s eq uip ped with a bubble
spaced at 2 k m distances s o a s to provide
w i n d o w for better viewing. Al l o b s e r v a ­
1 0 0 % c o ve ra ge of the colonies. Du rin g
tions of g e e s e and oth er highly visible
both t r a n s e c t and colony surveys, the
birds within an estim ated 2 0 0 m of the
p l u m a g e c o lo u r of the birds (blue or
flight path w ere recorded on aud io tape
white) w a s recorded w h e n e v e r all indi­
and the resulting data w ere later t r a n ­
v id u a ls in a flock or pair cou ld be r e a d ­
scribed.
ily identified to c o lo u r phase.
The s tu d y site w a s divided into three
The
transects
therefore u s e d to calculate m i n i m u m
(Figure
1). A r e a s
Central
and
1, 5 2 5 k m 2,
of the
Southern
Geese
Northern,
S tr a ta
2, 6 6 8 k m 2 and
were
2, 0 7 2 k m 2,
respectively. Ea ch year, t r a n s e c t s cov­
ratio
differing
densities
W h it e - f r o n t e d
the
of
lengths
of
and
were
strata b ased on expected differences in
m ethod
was
po pulation e s t i m a t e s and den sit ie s (±
sta n d a rd errors) for eac h s t r a t u m (Jolly
1969).
Po p u la tio n
d e n s it ie s
for both
y e a rs w ere ave ra ge d to calculate the
ered approxim ate ly 8 % of the area of
m e a n n u m b e r of g e e s e in the stratum.
the
Strata.
The s ta n d a rd err o r (S. E. ) of the m e a n
of
po pulation estim ate for each stra t u m
Northern
Transects
and
a ls o
Southern
c o ve red
8%
the
C e n tral S t r a t u m in 1994, but in 1995
w a s determ ined:
additional t r a n s e c t s wer e added to the
stratum , in c re a s in g the area surv eyed
S . E. - M l S ^ l n
to 1 5 % (Figure 1).
In 1995, three additional tr a n s e c t s
w ere surv eyed in a 5 5 5 k m 2 area i m m e ­
w h e re S¡2 is the va ria n ce of the stra t u m
popu lation e stim a te in yea r i and n is
W aterfow l surveys in the Rasm ussen Lowlands 189
the n u m b e r of y e a r s the s t r a t u m w a s
veys that w a s developed by the U. S.
su rveyed (ie two years). T he total p o p u ­
Fish
lation e stim a te for the L o w l a n d s w a s
C a n a d i a n Wildlife S e rv ic e ( A n o n y m o u s
the s u m of the individual s t r a t u m esti­
1987; D i c k s o n ef at. 1997). T h i s p ro c e ­
m a t e s and the varia n ce for the total
dure treats lone m ale s, m a l e s in flo ck s
popu lation estim ate w a s the s u m of all
of two to fo ur and pa irs a s indicated
s t ra t u m varian ces.
Wild li fe
b re e d in g
F e m a le G re ate r W h it e-fr onted and
Canada
a nd
G e e s e are
infrequently s e e n
pairs.
Service
and
Calculations
the
for the
total po pu lation size u s e d the n u m b e r
of indicated bre eding pairs multiplied
from the air if they are on nests, s o
by two added to the n u m b e r of birds in
ea ch o bservation of one or two g e e s e of
g r o u p s of five or more. Thu s, o b s e r v a ­
th e s e s p e c i e s w a s treated a s an indi­
ti ons of one to fo u r fe m a le s (no m ale
cated breeding pair (ie two birds] in c a l­
present)
culating
fo ur eid e rs of unidentified s e x w e r e not
num bers
of b reeding
geese
( A n o n y m o u s 1987). C a lc u la tio n s of total
popu lation siz e u s e d the n u m b e r of
and
o b s e r v a t i o n s of one to
u sed in the calculations.
Indicated breeding pa irs w ere not
indicated breeding pa irs multiplied by
c a lc u la t e d
two p lu s the n u m b e r of birds in g r o u p s
b e c a u s e the s e x of m a n y of the birds
for
Long-tailed
Ducks
of three or more. E s t i m a t e s of L e s s e r
could not be d i s tin g u is h e d from the air.
S n o w G e e s e w ere not adjusted for visi­
C a lc u la tio n s for the total po pulation
bility b e c a u s e the colonial nature and
size u s e d only the n u m b e r of L o n g ­
light
(see
tailed D u c k s observed, and t h u s did not
R e s u lts ) m a d e t h e m relatively e a s y to
a cc ou nt for nesting fe m a le s that wer e
plu m age
of t h e s e
geese
s e e fr om the air and t h u s relatively few
m i s s e d fr o m the air. Similarly, c a lc u la ­
birds w e r e
likely to be m is s e d . The
tions for o ther s p e c i e s s u c h a s loons,
n u m b e r of breeding S n o w G e e s e w a s
cranes, g u l l s and t e r n s u s e d only the
the total n u m b e r sig hted
le s s th o s e
s e e n in flo c k s of three or m o re birds.
n u m b e r of individua ls act uall y s e e n
du rin g the survey.
T u n d ra S w a n s are high ly visible and
Ad ju stin g o b s e r v a t i o n s to a ccount
are unlikely to be m i s s e d d u rin g the
for ' m i s s e d ' fe m a le s will still, in m o s t
surv eys, and ca lc u la t io n s of total p o p u ­
ca s e s , u n d e re st im a t e the actual p o p u ­
lation size u sed only the n u m b e r of
lation size b e c a u s e th ere are groups,
sw ans
b re e d in g
pairs o r lone birds for w h ic h none of the
pairs w ere calculated by s u m m i n g all
individuals w ere s ig hted fr o m the air.
o b s e rv e d .
Indicate d
s i g h t i n g s of one o r two s w a n s and then
B a s e d on w o r k carr ie d out in both the
dividing by two (Wilk 1988).
W estern
T h e n u m b e r of indicated bre eding
pairs
of King
E id e rs w a s
calculated
Canadian
Rasm ussen
2000;
A r c tic
Low lan d s
and
(Hines
the
et at.
H in e s & Wie be 2004), visibility
u s i n g the s t a n d a rd opera ting pro ce dure
corre ction fa ctors (VCFs) that had been
for waterfowl breeding population s u r ­
d ev e lo p e d
by
means
of
a
doub le­
190 W aterfow l surveys in the Rasmussen Lowlands
counting
w ere
(m a r k - r e c a p t u r e ) a p p r o a c h
used
( C a u g h le y
&
Grice
1982;
co lo n ie s located, with m o re than 8 0 % of
the 6, 700
ne sting
pa irs
being found
P o llo c k & K e n d a ll 1987; A n t h o n y et al.
there [Table 2). M a n y S n o w G e e s e w er e
1992). Overall po pu lation e s t i m a t e s and
fo un d
varian ces were
co lo n ie s (Figure 3) but oth er g r o u p s of
th en
determ ined
by
in o r n e a r one
of the thre e
applying the appropriate visibility c o r ­
n o n -b r e e d i n g S n o w G e e s e w ere s e e n
rection factor to the m i n i m u m p o p u la ­
e ls e w h e r e in the stu dy area. T h e esti ­
tion
m a te d
estim ates
and
variances
as
p o p u la t i o n
s iz e
was
4 2 , 041
d es cr ib e d by S m i t h (1995). Only m in i ­
birds. Twen ty per cent of the birds in a
m u m population e s tim a te s are report­
s a m p l e of 1, 154 S n o w G e e s e wer e blue
ed for le s s c o m m o n l y s ig hted s p e c i e s
p h a s e birds.
(for w h ic h V C F s cou ld not be de vel­
C a n a d a G e e s e and T u n d ra S w a n s
w ere reg ula rly distributed t h r o u g h o u t
oped).
the
s u r v e y are a
D en sitie s
Results
(Figures 4 and 5).
of C a n a d a
Geese
ranged
fro m 0. 9-1. 3 g e e s e / k m 2 in the three
Distribution and n u m b ers of w a t e r ­
strata, a nd the total popu lati on esti ­
fowl and o th er species
m ate w a s 6,412 birds, inclu ding 2,450
pairs (Table 1 ). T un dra S w a n s occ u rred
W h it e - fro n t e d
di stributed
G e e s e w ere widely
t h r o u g h o u t the
in s o m e w h a t lower den sit ie s (0.4 - 0 . 7
Low lands
b i r d s / k m 2) th a n
Canada
(Figure 2). M o r e than 23, 500 White-
total population
estim ate for T undra
fronte d
S w a n s w a s 3, 8 22 and included 1,632
Geese were
present
6, 2 6 5 k m 2 s u r v e y area, with
m ate ly t w o - t h i r d s
of the
in the
a p p r o x i­
Gee se. T he
pairs (Table 1 ).
individua ls
K ing
E id e r s w e r e the m o s t c o m ­
o c c u rrin g in the C e n t ra l Stra tu m . The
m only
den s itie s a v e ra g e d 2. 0 g e e s e / k m 2 in the
D e n s it ie s of K in g E id e rs w ere high e s t in
N o r t h e r n and S o u t h e r n Str ata and 6. 1
the
g e e s e / k m 2 in the
area (3.3, 2. 5 and 1.0 e i d e rs / k m 2 in the
A p proxim ately
p a i r s / k m 2)
Central
4, 4 0 0
were
Stratum.
pairs
present
in
observed
no rt h e rn
ducks
s e c t io n s
(Table
1).
of the s u rv e y
(0. 7
northern, cen tr al and s o u t h e r n strata,
the
respectively). T he total po pu lation esti ­
L o w l a n d s (Table 1], with over 7 0 % of
m ate for K i n g E id e r s w a s 13, 690 birds
these
Central
and inclu ded 6,393 pairs.
Overall,
L o ng -ta iled D u c k s ra n g e d from 0. 6-0. 7
pairs
Stratum
present
(1. 1
in the
p a i r s / k m 2).
D e n s it ie s of
G re ate r W h it e-fr onted G e e s e w ere the
d u c k s / k m 2 in the three strata, with a
second
total
m ost
abundant
species
of
w aterfo w l in the s u rv e y area.
p o p u la t i o n
estim ate
of
5, 4 2 7
d u c k s (Table 1).
L e s s e r S n o w G e e s e wer e the m o st
Data w e r e adeq ua te for esti m ati ng
a b u n d a n t s p e c i e s of waterfowl in the
m i n i m u m po pu lation s i z e s ( u n co rrec t­
s u rv e y area. T h e Inglis River co lony w a s
ed for visibility bias) fo r s e v e ra l oth er
the la rg est of the three S n o w G o o s e
W aterfow l surveys in the Rasmussen Low lands 191
Figure 2. The mean number of White-fronted Geese seen on each 2km segm ent during helicopter s u r ­
veys in the R a sm u sse n Lowlands, Central Canadian Arctic, in June 1994-95. Population estimates ±
standard errors for each stratum are indicated in boxes by the strata.
s p e c i e s of birds that o ccu rre d at lower
Southern limit of high densities of
den sitie s:
w a t e rfo w l
stellata,
G lau co us
R e d -t h ro a t e d
Pacific
G u lls
Loons
Larus
Loons
Gavia
Gavia pacifica,
hyperboreus,
T ha y e r's G ulls Larus thayeri, Arctic Terns
Sterna paradisaea, J a e g e r s Stercorarius
spp., and Sa n d h ill C r a n e s Grus canaden­
sis (Table 1). In addition, s m a l l n u m b e r s
of the following sp e c ie s were sighted
du rin g the surv ey s:
Rock
P t a r m ig a n
Lagopus mutus (7 in 1994, 34 in 1995),
S n o w y O w ls Nyctea scandiaca (5 in 1994,
6 in 1995), R o u g h - le g g e d H a w k s Buteo
lagopus (2 in 1994, 5 in 1995), Yellow­
billed L o o n s Gavia adamsii (2 pairs in
1994) and No rthern P in ta ils An a s a c u ta (a
group of 12 in 1994). The data w ere not
sufficient for d e t e rm in in g
population
e stim a te s for the latter species.
V ery
few
G ee se,
E id e rs
Greater
Lesser
or
W h it e - fr o n t e d
Snow
L o n g - t a il e d
G ee se,
K in g
Ducks
were
o b s e rv e d on the three tr a n s e c t s added
s o u th of the S o u t h e r n S t r a t u m In 1995
(Figures 2 and 3) and
d en sitie s for
th e se s p e c i e s w ere m u c h low er in th is
area than In any of the three strata. In
co n tra st,
m any
Canada
Geese
and
T un d ra S w a n s w ere o b s e rv e d on the
extra three tr a n s e c t s (Figures U and 5)
and d e n sitie s of th e s e two s p e c i e s were
s im i la r or h ig h e r in th is area than in the
three s u rv e y strata.
192 W aterfow l surveys in the Rasmussen Lowlands
Table 1. Estimated numbers and densities ± standard errors (S.E.) of waterfowl and other
species observed within the 6,265km2 survey area in the R a sm ussen Lowlands, Central
Canadian Arctic in June 1994-1995. Mean estimates have been adjusted by a visibility correc­
tion factor (VCF) when possible. Refer to Table 2 for estimates of Lesser Snow Geese.
Species
Year
Greater White-fronted G oose
Anser albifrons frontalis
16,329±1859
2.61 ±0. 30
15.0 2 5 ± 1 187
2.40±0. 19
Mean
(No VCF)
M ean (VCF]a
1.617“
2,425b
15,677± 1103
23, 516± 1530
2.50±0. 18
3. 75±0. 24
1994
224b
2,786+257
0.44±0. 04
1995
Mean
(No VCF]
Mean (VCF)a
403b
3, 10 9 ± 2 5 1
0. 50±0. 04
314"
470"
2,947±180
4.421 ±269
0.47±0. 03
0.71±0. 04
3436
435"
4,314±621
4,236±538
0.69±0. 10
0.68±0. 09
3891’
584b
4, 275±411
6. 412 ± 6 16
0.68+0. 07
1.02±0. 10
131"
164b
1,651 ±230
1,61 6±216
0.26+0. 04
0.26±0. 03
1994
1995
Mean
IN o VCF)
Mean [VCFla
Tundra Sw an pairs
Density (birds/km I
±S. E.
1,312"
1.921”
Canada Goose
Branta canadensis hutchinsii
Tundra Swan
Cygnus columbianus
Numbe r of Birds
±S. E.
1994
1995
Greater White-fronted G oose
pairs
Canada Goose pairs
Number on
Transects
1994
1995
Mean
[No VCF)
148b
1.634±158
Mean (VCF)a
22Γ
2,450±236
0.26±0. 03
0.39±0. 04
1994
1995
Mean
340
373
4,254±427
3,389±328
0.68±0. 07
0.54±0. 05
[No VCFI
357
3,822±269
0.61+0. 04
1994
1995
Mean
142'
162'
1,778±117
1,485±141
0.28±0. 02
0.24±0. 02
(No VCF)
152'
1,632+92
0.26±0. 01
King Eider
1994
672d
8,445±786
1.35±0. 13
Somateria spectabilis
1995
830'
6,928±710
1.11±0. 11
Mean
King Eider pairs
(No VCF)
751"
7,687±530
1.23±0. 08
M ean (VCFla
1,338a
13,690±944
2. 19±0. 15
1994
1995
Mean
(No VCF]
Mean (VCF]
309d
392"
3,888±350
3,291 ±353
0.62±0. 06
0. 53±0. 06
35Γ
624
3, 590±249
6,393±443
0.57±0. 04
1.02±0. 07
Long-tailed D uck
1994
157
Clangula hyemaIis
1995
Mean
236
197
1,987±531
1,993±416
1,990±337
0.32±0. 08
0.32±0. 07
0.32+0. 05
Mean (VCFla
536
5,427±920
0.87±0. 15
W aterfow l surveys in the Rasmussen Lowlands 193
T ab le 1
continued
Species
Year
Red-throated Loon
Gavia stellata
Number on
Transects
Numbe r of Birds
±S. E.
Density (birds/km2]
+S. E.
1994
1995
32
18
407±80
0.06±0. 01
164±49
0.03±0. 01
Mean
(No VCF]
25
285±47
0.05±0. 01
1994
1995
69
870±142
467±91
0. 14±0. 02
56
(No VCF)
63
669±84
0. 11±0.01
1994
92
102
1.138±322
879±216
0. 18±0. 05
0. 14±0. 03
(No VCF]
97
1.008±194
0. 16+0. 03
1994
1995
Mean
48
22
593+505
154+81
0.02+0. 01
(No VCF]
35
373±256
0.06±0. 04
1994
1995
19
34
236±77
259+96
0.04±0. 01
0.04±0. 02
(No VCF]
27
247±62
0.04±0. 01
1994
1995
Mean
86
81
1,070±200
722±92
0. 17±0. 03
0. 12+0. 01
(No VCF]
84
896±110
0. 14±0. 02
1994
1995
Mean
54
52
681±170
506±104
0. 11+0. 03
0.08±0. 02
(No VCF)
53
594+100
0.09±0. 02
Pacific Loon
Gavia pacifica
0.07±0. 01
Mean
Glaucous Gull
Larus hyperboreus
1995
Mean
T hayer's Gull
Larus thayeri
Arctic Tern
Sterna paradisaea
0.09±0. 08
Mean
Sand h ill Crane
Grus canadensis
Jae ger (unidentified to species]
Stercorarius spp.
a Visibility Correction Factors: Greater White-fronted Goose and Canada Goose 1.5, King Eider 1.781, and Long-tailed
D uck 2.727 (Hines et a i 2000, H ines and Wiebe 2004).
b Sigh tings of 1-2 geese considered to be a pair.
Sigh tings of 2 sw a n s considered to be a pair and sigh tin gs of 1 sw an considered to be 0.5 pair.
11 Sigh tings of pairs, lone m ales and flocks of 2-4. m ales considered to be pairs. Observations of 1-4 fem ales and 1-4
King Eiders of unidentified sex are excluded.
194 Waterfowl, surveys in the Rasmussen Lowlands
Table 2. Estimated numbers of Lesser Snow Geese in the R a sm ussen Lowlands. Central
Canadian Arctic, in June 1994-1995.
L o ca tio n
Y ear
Total B i r d s
Inglis River colony
199Λ
1995
13,708
10,763
5,943
5,330
Mean
12,236
5,637
1994
1995
8,226
3, 179
887
1,126
Mean
5,703
1,002
1994
1995
Not surveyed
99
50
Mean
99
50
1994
1995
22, 109
25,898
Mean
24,004
1994
1995
44, 043
39, 939
6,820
6,506
Mean
42,041
6,688
Shepard Bay colony
Sn ow Goose River colony
A reas outside the colonies
Total in R a sm u sse n Lowlands
N e s t in g P a i r s
-
-
Figure 3. The mean number of L esser Snow Geese in colonies and seen on each 2km segm ent during
helicopter surveys in the R a s m u s s e n Lowlands, Central Canadian Arctic, in June 1994-1995. Population
estimates for each stratum are indicated in boxes by the strata.
195
Figure 4. The mean num ber of Canada Geese seen in each 2km segm ent during helicopter surveys in
the R a s m u s s e n Lowlands in June, 1994-1995. Population estimates ± standard errors for each stratum
are indicated in boxes by the strata.
Figure 5. The mean number of Tundra Sw a n s seen in each 2km segm ent during helicopter surveys in
the R a sm u sse n Lowlands in June 1994-1995. Population estimates ± standard errors for each stratum
are indicated in boxes by the strata.
196 W aterfow l surveys in the Rasmussen Lowlands
not report V C F s for overall populations,
Discussion
such
e s t i m a t e s can be derived from
inform ation presented in their Table 2.
Reliability of estim ates
A e ria l
surveys
A v e ra g e V C F s of 1.5 for C a n a d a G e e s e
of w a t e r f o w l and
o ther wildlife are subject to a n u m b e r
of b ia s e s that influence the probability
of being sighted.
Fo r the s p e c i e s of
w aterfo w l m o s t frequently en counte red
in the pre se nt surv eys, attem p ts wer e
m a d e to ov e r c o m e this bias by applying
visibility corre ction factors. Fo r r e a s o n s
d i s c u s s e d e ls e w h e r e (Hines ef al. 2000;
H in e s & Wiebe 2004), it is probable that
the visibility correction fa ctors de vel­
oped
using
the
'do uble
'm ark-recapture'
somewhat
low,
conse rv ativ e
c o u n tin g '
approach
th e re fo re
estim ates
w o uld
or
be
producing
of population
size. The only c o m p a r a b l e information
on visibility bi as in helicopter s u r v e y s of
arctic
w aterfow l
was
presented
by
B r o m l e y ef al. (1995) for White-front ed
G e e s e and C a n a d a Geese.
B r o m l e y ef
at. (1995) indicated that the visibility of
and 1.8 for White-fronted G e e s e c a lc u ­
lated fr o m their data are s im i l a r or
slightly h i g h e r than the estim ate of 1.5
used
for
these
species
in
the
R a s m u s s e n L o w l a n d s surveys.
The
th ree
Snow
Goose
colonies
found in the L o w l a n d s are th o ugh t to
re p resen t virtually all the nesting p o p u ­
lation there. Given the high visibility of
this species, and the a m o u n t of time
s p e n t by the a u t h o r s and their c o l­
le a g u e s ( J o hn sto n ef al. 2000) in flights
over the lo wlands , it is unlikely that any
nesting co lo n ie s w ere m is s e d . In a d d i­
tion, repeat s u r v e y s of the S n o w G o o s e
co lo n ie s produ ced e s tim a te s that wer e
within
14%
of the mean, s u g g e s t i n g
that the 2 - k m wide t r a n s e c t s surv eyed
fro m
higher
altit ude
gr ou nd) w ere
(230m
above
a d eq ua te for counti ng
g e e s e in the colonies.
nesting g e e s e varied from y ea r to yea r
and w a s
nesting
lowest
in y e a r s
success.
of highest
Recognising
that
potential fo rm of bias, it w a s r e c o m ­
m e n d e d that aerial s u r v e y s s h o u l d be
repeated over m o re than one y e a r and
ave rage V C F s (derived from data from
s e ve ra l years) s h o u l d be applied to the
mean
annual
p o p u la t i o n
estim ates
(Hines ef al. 2000; H in e s & Wiebe 2004-).
That a p p r oa c h w a s adh ered to in the
present
s tu d y
and
should
limit the
influence of a n n u a l variation in visibility
on
estim ates
of a v e r a g e
pop u la tion
size. Alth ough, B r o m l e y ef al. (1995) did
W a te rfo w l distribution and abundance
The re s u lt s of this stu dy impro ve on
and up date pre vious f in d in g s ( M c L a r e n
ef at. 1977; Z d a n & Bra ck ett 1977; Allen
& Hogg
1994)
1978; B r o m l e y & S t e n h o u s e
that the
im p o r ta n t
Low lands
b r e e d in g
and
site
is an
sum m ering
area for w aterfo w l and, in particular,
supports
h igh
num bers
of
Greater
W hit e-fronted Geese. The a u t h o r s e sti­
mate d that 23, 500 W hite-fronted G ee s e
(3.4 g e e s e / k m 2) w ere p re se nt on their
survey
a re a
d e n s it ie s
with
average
b re e d i n g
of 0. 7 p a i r s / k m 2. S u m m e r
Waterfowl surveys in the R a s m u s s e n Low lands 197
d e n sitie s of White-fronted
G e e s e are
K e r b e s and K. M. M e e re s, pers. c o m m . ).
typically <3 g e e s e / k m 2 [Ely & Dzubin
Therefore, the a u t h o r s ' r e s u lts s u g g e s t
1994), s o the den sit ie s recorded for the
that
L o w l a n d s are c o m p a r a b l e to or h ig h e r
P o p u la t i o n
th an for m o s t o ther arctic areas. The
s u m m e r.
authors'
of
the
used
M id-con tinen t
the
Low lan d s
in
h ig h e r
M c L a r e n e ta t. (1977) estim ated that
than the 10, 000 g e e s e o b serv ed in a
few er than 1,000 C a n a d a G e e s e us e d
9, 8 2 5 k m 2 s u rv e y (1.0 g e e s e / k m 2 u n c o r ­
the L o w l a n d s in the m i d - 1 9 7 0 s w h e r e ­
rected
e s tim a te s w ere a ls o
>0. 5 %
the
a s the a u t h o r s ' re s u lt s indicated that
L o w l a n d s in the m i d - 1 9 7 0 s ( M c L a r e n et
fo r
there w ere 6,400 g e e s e present. The
al. 1977) but are co n sis te n t with oth er
C a n a d a G ee s e e n co un tered d u rin g the
findings
visibility
that
bias)
in
G r e a t e r W h it e - f r o n t e d
a u t h o r s ' s u r v e y s w e r e probably from
G o o s e n u m b e r s have in c re a s e d sin ce
the T a l l g r a s s
that time
b e lo n g
( C a na d ia n
Wildlife Serv ic e
W aterfowl C o m m itt e e
population
2002). A u t u m n
inve ntories
indicated
that
Prairi e
to the
ra ce
Popula ti on
B.
( M c L a r e n et al. 1977; B e llr o s e
The T a llg r a s s
and
c. h u tc h in s ii
1980).
Prairi e Popula ti on
has
the M id -co n tin e n t Popu la tio n of Whit e-
in cre a sed s in ce the
fronted G e e s e ave ra ge d a bout 0. 9 m i l ­
M o s e r 1998), w hich c o r r e s p o n d s with
lion birds in 19 9 4 -9 5 ( C a na dia n Wildlife
the a u t h o r s ' finding of in cre a sed n u m ­
S e rv ic e W aterfo w l
Com m ittee
2002),
1970s
(Sha rp
&
be r s in the Lo w la n d s . The m e a n winter
s u g g e s t i n g that the L o w l a n d s s u p p o r t ­
estim ate
ed > 2 % of the overall population d urin g
Po pula ti on w a s approxim ate ly 250, 000
sum m er.
birds from 19 9 2 -9 3 to 19 9 5 -9 6 (S ha rp &
It w a s esti m ate d that over 42, 000
Lesser
Snow
13, 0 00
Ge ese,
nesting
i n c lu d i n g
geese,
used
over
the
M oser
increase
fro m
the
5, 0 0 0 - 6 , 000
1998),
the
T allg rass
ind ic a t in g
L o w l a n d s s u p p o r te d
P ra irie
that
over 2 %
the
of this
population.
L o w l a n d s in 1994-95. Th is is a s u b s t a n ­
tial
for
M c L a r e n & M c L a r e n (1984) reported
that the R a s m u s s e n L o w l a n d s site is a
L e s s e r S n o w G e e s e that M c L a r e n et at.
prim e nesting area f o r T un dra S w a n s in
(1977)
the
found
there
d u rin g
the
m id -
1970s, but pa ra lle ls the large i n c r e a s e s
m id - 1 9 7 0 s .
T h e y es tim a te d
5, 500 s w a n s w ere
using
that
a 9, 8 2 5 k m 2
that have o ccu rred at o ther co lo n ie s in
area (0.6 s w a n s / k m 2) in the L o w la n ds,
the C e n t ra l C a n a d i a n Arctic ( A b ra h a m
w hich is c o m p a r a b l e to the 1 9 9 4 -1 9 9 5
& Jefferies 1997; R . H. K e r b e s and Κ. M.
esti m ate of 3, 800 s w a n s on the a u t h o r s '
Meeres,
Se rvic e,
6, 250 s u rv e y area (also a density of 0. 6
S a s k a t o o n , SK, pers. c o m m . ). The M i d ­
s w a n s / k m 2). The w in t e r e stim ate of the
Canadian
Wild li fe
continent Popula tion of L e s s e r S n o w
E a s te rn
G e e s e w a s estim ated to be clo se to 4
w a s a pproxim ate ly 80, 000 birds from
Popula ti on of T un dra S w a n s
million nesting birds in 1 9 9 7 -9 8 and
1993-1996
probably n u m b e r e d 6 million a du lt s if
Therefore, 5 % or m o re of the E a s te rn
non-breeders
Popula ti on u s e s the Lo w la n d s .
are
i n c lu d e d
( R . H.
(Sharp
&
M oser
1998).
198 W aterfow l surveys in the Rasmussen Lowlands
In stri kin g co n trast to the situation
(>1%) of specific p o pu la tio ns of s h o r e -
with g o o s e po pu lations, King Eid e r and
birds and o th er s pecies. The a u t h o r s '
have
r e s u lts s u p p o r t previ ous s tu d ie s that
declined greatly in the L o w l a n d s sin ce
L o n g - t a i led
Ducks
the L o w l a n d s site is an im porta nt area
the
it w a s
for w aterfo w l and fu rth er s tre ngthe n
estim ate d that 13, 690 King E id e rs and
the r e c o m m e n d a t i o n s that the area be
m id -1 9 7 0 s .
In
num bers
1 9 9 4 -1 9 9 5
5,427 Long-t ail ed D u c k s w ere present,
c o n sidere d for protection. In particular,
w h e r e a s M c L a r e n e t at. (1977) found
the a u t h o r s ’ fi n d in g s s u g g e s t that the
30, 0 0 0 -3 5 , 000 K ing E id e rs and 10, 000-
R a s m u s s e n L o w l a n d s is us e d in s u m ­
15, 000
m e r by m o r e than 2 % of the M id -co n ti-
Lo ng -ta il ed D u c k s in the m id-
1970s. The decline
in n u m b e r s
may
nent Popu la tio n of G re ate r White-front-
have been even g r ea te r than s u g g e s t e d
ed Geese,
by th e s e e s t i m a t e s b e c a u s e the aerial
Prairie
c o u n ts of M c L a r e n e ta t. (1977) w ere not
abo ut 5 % of the E a s te rn Popula ti on of
adjusted for visibility bi as (and, thus,
T un dra S w a n s and probably 1 % of the
could have been > 8 0 % higher). B a s e d
eastern
on g r o u n d
Eiders. B a s e d on n u m b e r s and d e n s i ­
c o u n t s of bre eding
pairs,
Gratto-Trevor et al. (1998) a ls o d o c u ­
ties
over 2 %
Popu la tio n
a rctic
of
of the T a llg r a s s
of C a n a d a
p o p u la tio n
sho re bird s
Geese,
of
present
K in g
in
the
m ente d a sig nifi ca nt decline in King
R a s m u s s e n Lo w la n d s , J o h n s t o n et a i
Eid e r n u m b e r s in the L o w l a n d s from
(2000) p ro p o s e d a potential bo u n d a ry
the
m id -1990s.
for a N a t io n a l Wildlife Area that w ould
P re c ise e s tim a te s of the n u m b e r s of
include all of this s t u d y 's N o rt h e rn and
m id -1 9 7 0 s
to
the
King E id e rs and Long -ta il ed D u c k s in
Central
the E a s te rn C a n a d i a n Arctic are l a c k ­
S o u t h e r n S t r a t u m and the e s c a r p m e n t
ing, but, b ased on o b s e rv a tio n s of re la ­
to the east of the stu dy area, a high
tive waterfowl n u m b e r s e ls e w h e r e in
density nesting area for the tundra race
the arctic, the a u t h o r s s u s p e c t that at
of P e r e g r i n e F a lc o n s Falco p e re g rin u s
least 1 % of the e a s tern C a n a d i a n arctic
tu n drius ( S h a n k 1995). Thus, this p ro ­
po pu la tion
po sed b o u n d a ry e n c o m p a s s e s the high
of K in g
E id e r s
uses
the
Str ata ,
plus
m ost
of
its
density a r e a s of W hite-fronted G ee s e
Lo w la n ds.
and
K in g
E id e rs ,
the
Lesser
Snow
G o o s e co lo n ie s and m o s t of the a r e a s
Potential for a N atio n al Wildlife Area
with high den s itie s of o ther waterfowl.
J o h n s t o n et al. Í2000] r e c o m m e n d e d
The a u t h o r s a gree with the s u g g e s t i o n
that the R a s m u s s e n L o w l a n d s site be
by J o h n s t o n et al. (2000) that their p ro ­
considered
posed
fo r
designation
as
a
b oundary w ould
be a u s e f u l
N at io n a l Wildlife Ar e a b e c a u s e of its
start ing point w h e n d i s c u s s i o n s about
r i c h n e s s of sh o re b ird sp eci es, its p o s i ­
the c o n se rv a t io n
tion in an eco log ic a l transition zone, its
begin.
a b u n d a n c e of di verse and suita ble bird
habitat,
and
its s ig n ific a n t
p o rt io n s
status
of the
area
W aterfow l surveys in the Rasmussen Lowlands 199
A c kn o w le d g e m e n ts
W e greatly appreciate the help of
Vicky J o h n s t o n
and
Stephen
Pepper
w h o allowed u s to u s e their field c a m p
and facilitated o u r field w o r k in oth er
w a y s a s well. In addition, w e th a n k J-F.
D u f o u r for help with the m a n u sc rip t,
the
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Continental Sh e lf
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1991 progress report, Unpublished
report. Alaska Fish and Wildlife Research
Center, Anchorage, Alaska; 30 pp.
ing aircraft and logistic support, and
two rev iewers for their c o m m e n t s on
the m anu sc ript.
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