223
SOME OBSERVATIONS OF THE MOOSE HUNT IN
THE BLACK STURGEON AREA OF NORTHWESTERN ONTARIO.
H. R. Timmermann
Ontario Ministry of Natural Resources
Wildlife Biologist, Thunder Bay, Ontario
Abstract ,c Antler development, body size and eye lens
weight were related to age. Moose of ages 8.5 to 11. 5
years generally produced the largest sized antlers as
measured by three dimensions. Body measurements and
weights continued to increase with age, with males being
larger than females. Eye lens weights separated only
calf and yearling age classes reliably.
The Black Sturgeon timber cutting limits bordering the west
side of Lake Nipigon is a vast area stretching nearly 150 miles'
north to the town of Armstrong and south to the Trans Canada Highway
#17.
These limits, for many years a favourite haunt of sportsmen,
represent an ideal model of timber cutting followed by regeneration
and moose harvesting.
The pulpwood operations that began in the
late 19)0's have followed what we believe to be a progression most
compatible with moose production.
Although major cutting operations
in the area ceased in 1965 some logging is planned to continue
until 1975, generally in a scattered pattern throughout the limits.
The land when disturbed by logging produces highly favourable
moose habitat.
The Black Sturgeon Limits (B.S.L.) is placed by Rowe in Section
B9 of the boreal forest and is typical of a large area of that
Section that is not under the immediate influence of Lake Superior.
224
Throughout the area the precambrian basic intrusive bedrock of
gabbro and diabase is overlain by relatively deep glacial deposits
according to Ellis (1972).
To the west and south of Black
Sturgeon Lake this consists mainly of water worked till.
sand plains occur to the northwest.
ing with only occasional rock bluffs.
quent.
The topography is gently rollBedrock exposures are infre-
In the numerous streams and rivers stretches of rapid flow
alternate with sluggish sections and swampy areas.
materials vary
deep.
Extensive
Soil parent
in texture from sand to clay loam and is usually
Stands composed of aspen, birch, spruce and balsam fir are
typical of most sites.
Past logging disturbance appears to favour
the development of hardwoods at the expense of the conifers.
On
moist sites black spruce becomes prominent and on dry sites jack
pine becomes important.
Although the ARDA land classification did
not include this area, extrapolation of their findings would indicate
a rating of high 4 or even a 3 in some sections.
Access for hunting is provided by a network of main and secondary haul roads estimated at 600 miles, plus countless miles of tote
roads and skid trails.
Because the logging was carried out on an
extensive basis, with small cuts occurring over a period of years,
the roads were kept in a constant state of good repair.
l-iore recently
recreational funds have been spent on an annual maintenance of main
and secondary arteries.
Public use of the area had been controlled
by a timber company gate situated 18 miles north of Highway #17 on
the main Armstrong road.
by permit only.
During the late 1950's access was allowed
The year 1965, however, marked the end of major
cutting operations and hence gate control.
The gatehouse was subse-
quently turned over to the Department of Lands and Forests (now Ontario
Ministry of Natural Resources) for use as a game and fish check
225
station.
Alternate access routes to the area were developed in
1969 and 1970.
A second check station situated on the Spruce River
Road (Highway #800) was subsequently established in order to monitor
all hunters in the area.
kept since 1962.
Records of the moose harvest have been
Company gate men cooperated by recording the moose
kill for the period 1962-65.
Beginning in 1966 the Department conducted an intensive study
of the early season moose hunt in the area.
Hunters and harvested
game were monitored past the check station during the first two
weeks of the season at a time when approximately 80% of the annual
kill takes place.
Interim.reports concerning the early season moose
harvest for the area were documented by Timmermann (1966) and (1968)
and Tolmie (1967).
Initially check station activities were patterned after those
carried out on the long established Red Lake Road Station.
During
the six year study many new approaches at data collection were attempted, some discarded and others retained in an overall effort to
obtain factual information concerning moose hunter activities in
specific areas within the B.S.L.
This data includes information on
hunter activity and harvest, sex and age composition of the kill,
time of day and location of kill, antler development related to age,
weights and measurements related to age, eye lens weight related to
age, as well as specific data concerning kill locations related to
access, and past logging activities.
We are now specifically concerned with how long a quality hunt
can be maintained under the present reduced logging operation.
The
purpose of this paper is to examine the data that has been collected
to determine which information will be most valuable to indicate
changes in the moose population or in the utilization of the resource
226
by hunters.
All data is being collated and evaluated to be presen-
ted in a larger report.
with here.
Only three of the sections will be dealt
Results will be reported and tentative conclusions made
wherever possible.
ANTLER
DEVELOP~ffiNT
RELATED TO AGE
***~,~,* *~,*********
******* ** ***
Antlers of big game are considered souvenirs or trophies of
the hunt by most sportsmen.
Moose exhibit the greatest antler dev-
elopment of any North American big game animal.
Few studies except
those conducted by Cringan (1955) exist regarding moose antler
development related to age.
Cringan's findings related antler dev-
elopment to wear class age and concluded that the greatest developed
antlers generally occur in the wear class Vll or 8.5 to 10 year old
age category.
The incisor cementum ring count ageing of bulls being
transported past the check station presented an opportunity to compare actual age to antler development.
METHODS
All specimens were measured during the first two weeks of the
fall season 1966, 1968, 1969, 1970 and 1971 at the Black Sturgeon
check station.
Three basic measurements were taken using a steel
tape measure calibrated in 1/8 inch intervals.
The beam circumfer-
ence was measured on either the left or right side as most convenient and recorded.
The maximum antler spread was measured between
the widest points judged to touch two parallel lines drawn perpendicular to the main axis of the skull.
The third criterion used in
determining development tallied the total number of points on both
beams over one inch long and longer than wide.
The incisor cementum
227
ring count ageing technique as described by Sergeant and Pimlott
(1959) was used to correlate antler development with age.
For each
age classification (1.5 to 14.5 years) each of the three measurements
were averaged to the nearest 1/10 of an inch.
RESULTS AND DISCUSSION
Table 1 illustrates thrGe moose antler measurements related
to age based on 383 specimens harvested in October.
Figurel further
illustrates antler variability related to age, based on the total
number of points more than one inch in length as well as the maximum
antler spread.
It was found that moose in the Black Sturgeon area,
of ages 8.5 to 11.5 years, generally produced the largest development
of antlers (Timmermann, 1971).
A progressive increase occurred in
all three measured characteristics from the age of 1.5 to 6.5 years.
The greatest average maximum spread (51.3") occurred at 11.5 years
of age; the greatest average number of points (19.8) occurred at
10.5 years; and the largest average beam circumference (8.2")
occurred at 11.5 years.
Animals older than 11.5 years showed a
marked reduction in antler development.
A great deal of variation
occurs in antler shape and size for each age classification.
sets are ever exactly alike.
No two
The typical antlers of a Black Sturgeon
yearling have two or three points on each side; however, antlers
bearing four or five and in one case, seven points on each side were
recorded in the sample of 107 yearlings measured and aged.
Their
greatest spread varied from 14.8 to 32.0 inches with an average of
24.8 inches.
Older moose show a great deal of variability and this
fact makes judging the animal's age by antler growth an impossible
task.
Antlers from 55 moose at the age of 2.5 years, for example,
ranged from a minimum of 24.8 inches to a maximum of 46.5 inch spread.
Table 1.
Three moose antler measurements related to age based on 383 specimens harvested in October.
Age
*(CRC)
(Years)
Average
Beam Circumference
(in.)
Sample
Size
107
1.5
2.5
55
56
3.5
/,.5
34
31
5.5
6.5
17
23
7.5
8.5
19
10
9.5
10.5
9
8
11.5
6
12.5
6
13.5
2
14.5
*CRC = Cementum Ring Count
Variability
Age (year)
Minimum
Average
MaJdmum
Sample Size
in
Average
Maximum Spread
(in. )
4.9
5.9
6.3
7.0
7.3
7.8
7.6
8.0
7.6
7.7
8.2
8.0
6.9
7.5
Average
Number of Points
more than 1" long
5.5
10.2
12.1
16.2
18.5
17.9
17.2
17.9
16.2
19.9
17.6
18.2
16.7
15.0
24.3
33.3
38.3
42.6
48.0
Ie.4
48.1
51.0
51.2
50.5
51.3
49.3
45.6
44.3
greatest spread of moose antlers based on 383 specimens
h~vested
N
N
00
in October.
1.5
2.5
3.5
4.5
5.5
6.5
7.5
8.5
9.5
10.5
11.5
12.5
13.5
U.5
14.8
24.3
32.0
107
24.8
33.3
46.5
55
30.8
38.3
49.0
56
29.0
42.6
53.3
34
31.8
48.0
58.8
31
35.8
48.4
53.3
17
34.3
48.1
55.3
23
41.3
51.0
63.5
19
33.8
51.2
57.0
10
L.1... 8
45.5
51..3
59.5
8
42.0
49.3
58.8
6
31.5
1..5.6
51.5
6
43.0
J..4.3
1..5.5
2
50.5
61.3
9
Variability in number of points (more than one inch long) on moose antlers based on 383 specimens
harvested in October.
Age (year)
Minimum
Average
Maximum
Sample Size
1.5
2.5
3.5
4.5
5.5
6.5
7.5
8.5
9.5
10.5
11.5
12.5
13.5
14.5
2.0
5.5
14.0
107
5.0
10.2
14.0
55
7.0
12.1
20.0
56
9.0
16.2
21.0
34
10.0
18.5
26.0
31
12.0
17.9
27.0
17
9.0
17.2
26.0
23
14.0
17.9
24.0
19
9.0
16.2
29.0
10
14.0
19.9
28.0
9
12.0
17.6
26.0
8
9.0
18.2
29.0
6
8.0
16.7
23.0
6
12.0
15.0
18.0
2
229
The number of points also varies a great deal.
Both the 9.5 year
old and the 12.5 year old age samples included antlers with as few
as nine and as many as twenty-nine pOints.
A sample of antler measurements were compared from so-called
accessible areas (by vehicle) and inaccessible areas (by aircraft).
The accessible areas generally have been recently disturbed by logging whereas the inaccessible areas have had no logging.
ent correlation
c~uld
No appar-
be found between these two types of areas on
the basis of the data examined.
In some cases mean measurements
tended to be higher in accessible areas for some age classes and in
other age classes they were higher in inaccessible areas.
This also
tended to be the case for the total number of points related to age.
It is felt that the greatest single factor limiting a valid comparison was the small sample size availaole from inaccessible areas.
230
antler spread
~
.....
no. of points
(n·383)
sample size
107
55
56
3~
17
31
~
~
50
19
~
Ii
6
10
t
j
.E
1
23
fr. . .
6
tt
I
I
I
~
D
E
~
30
.~ ~
LJ t
1~
2'.<,
+
3'.<,
~...,
,'.<,
61(,
7'.<,
I'..,
91(,
10'..,
HI(,
121(,
13~
I~""
age in y.aol
Figure 1.
Moose antler variability related to age.
WEIGHT AND MEASUREJIlENTS RELATED TO AGE
****** **~( *********~(** *~(***** *~, ***
Hunters continually speculate on the live weight of moose which
they harvest.
Game managers on the other hand face the dilemma of
being unable to accurately calculate weight since few Ontario weights
have been fully documented.
Each year stories of moose in the 1,500
to 1,800 pound range are circulated.
Due to the large size of this
231
species, it is not an easy task to weigh moose unless special equipment is available.
One of the most difficult problems encountered
is that of getting both scale and freshly killed moose together.
Bearing these factors in mind it was decided to attempt to weigh
as many as possible of the whole dressed moose (i.e. with only the
blood and viscera removed) being transported past the check station.
V~THODS
All specimens were weighed and measured during the first two
weeks of the fall hunting season, 1966 through 1971.
Vehicles carry-
ing whole moose generally drove beneath a fixed overhead beam supporting a block and tackle with a scale attached.
The scale was lowered
and affixed to the animal by means of a heavy rope.
The entire
carcass was then elevated by hand until it swung clear of all ground
support.
Two types of weighing scales were employed.
In 1966 a
large dial scale calibrated in 20 pound intervals and found to read
accurate within 10 pounds was used.
In all subsequent years a Dillon
Dynamometer calibrated in 10 pound intervals and found to read accurate within 5 pounds was employed.
In most cases all body measurements were taken on the elevated
animal using a steel tape measure calibrated in 1/8 inch intervals.
Body measurements recorded included:
total length, shoulder height,
neck circumference, heart girth, ear length and hind foot length.
Estimated live weights were calculated using a 24% loss on field
dressing estimated by Nunan (1965).
Both wear class age as described
by Passmore, Peterson and Cringan (1955) and the incisor cementum
ring count age (Sergeant and Pim10tt, 1959) were recorded for each
specimen wherever possible.
232
RESULTS AND DISCUSSION
A total of 81 aged moose were weighed and measured during the
six year study.
The heaviest animal weighed was a 4.5 year old bull
who tipped the scale at 1,050 pounds field dressed weight.
A male
calf weighing 240 pounds field dressed was the lightest animal documented.
The variability in dressed weights are shown in Table 2
and Figure 2.
Table 2.
Male
Variability in Field Dressed Weight of Black
Sturgeon Moose by Sex and Age
Minimum
240
440
565
630
980
720
Average
309
561
718
713
1015
886
Maximum
375
740
830
800
1050
1005
7
19
8
8
2
5
FEmale Minimum
305
470
650
Average
345
509
689
Maximum
410
600
727
3
7
2
Sample Size
Sample Size
810
683
1
o
1
755
910
815
875
1
2
600
550
625
628
650
705
2
2
Seven male calves averaged 309 pounds while three female calves
averaged 345 pounds dressed weight.
weighed 410 pounds field dressed.
The heaviest calf, a female,
Nineteen male yearlings averaged
561 pounds field dressed while seven females averaged 509 pounds.
Eight bulls aged 2.5 years old averaged 718 pounds while two females
of the same age averaged 689 pounds
dres~ed.
It appears from the
limited data that in each age category except calves, males are some-
233
what heavier than females.
The greatest weight increase occurs
during the first half of an animal's life and continues somewhat
reduced up to three years of age after which increased growth tends
to level off.
The very rapid growth of calves during the first five
months of their lives has also been documented by Simard (1970) in
Quebec where calves reach a live weight of 300 to 500 pounds by
October.
Very old animals (13.5+ years) appear to be lighter on the
average than those in the prime or middle age category.
Additional
weights of older animals are needed however to draw more definite
conclusions.
The heaviest animals weighed were bulls in the 4.5 and
5.5 year old age category.
In three cases a complete live or round weight except for blood
loss, was followed by field dressing and re-weighing.
varied from 14.8 to 28.9%.
Weight loss
It appears that there may be a good deal
of variation concerning percentage weight loss due to field dressing among sexes and ages.
It should therefore be stressed that the
24% loss described by Nunan (1965) is an average rule of thumb rather
than an accurate method of calculating such weight loss.
Of the six body measurements taken along with body weight, most
tended to increase as the animal increased in age from calf to 2.5
years.
Again as found with weight, it appears from the limited data
that in each age category except calves, males are somewhat larger
in body form.
length.
This dimensional difference shows up well in total
Ear length and hind foot measurements tend to have reached
maximum growth by 2.5 years for both sexes.
234
1100
-
0
1000
t>
1 00
1
o:!
100
.
.5
i
r
1
."
600
500
400
J!
~
co:
300
male
IwnaIe •
200
meano~(n'7")
mean
.6. ~/
100
~,
I~,
21-,
31-,
41-,
,I-,
,It,
age
Figure 2.
7~
lit,
.It,
IOIt,
lilt,
12~,
13~
1.1t,
In~.
Variability in field dressed. weights of moose
related to age and sex.
EYE LENS WEIGHT RELATED TO AGE
*** **** ****** ******* ** ***
The use of the eye lens weight as a criterion of ageing is
based on the concept that lens growth does not cease with that of
the rest of the body, but is continuous throughout the whole period
of the animal's life.
Since Lord (1959) described the use of the
oven dry weight of the eye lens for ageing cottontail rabbits
(Silvilagus floridanus) this technique has been applied to a number
of other mammals and birds with varying degrees of success.
Simkin
(1967) examined eye lens weights of moose and found considerable
overlap among age classes.
The objective of this study was to gather
235
lens weight information to directly compare to that collected by
Simkin.
METHODS
The methods of collection, preservation, age determination and
lens weight calculation closely followed those described by Simkin
(1967).
All calves and yearlings were aged by tooth eruption.
The
balance of the adults 2.5 years old and older were aged by the incisor cementum ring count technique as described by Sergeant and
Pimlott (1959).
RESULTS AND DISCUSSION
Table 3 illustrates the comparison of the eye lens weights by
sex and age using this ageing criterion.
A total of 481 moose (328
males and 153 females) were aged, placed into one of sixteen age
classifications and mean weights of each classification calculated.
The lightest lens weighed came from a male calf being .2739 grams
and the heaviest from a thirteen year old male whose lens weighed
.9588 grams.
Figure 3 further illustrates the actual lens weight distribution
related to age.
Continuous data, above and below the mean is shown
by means of a diamond shaped distribution pattern centered about
each mean.
Individual lens weights which fall outside this contin-
uous distribution pattern are
s~parately
plotted.
Only 3 of 142
lenses taken from yearling moose fall in the 2.5 year old continuous
weight distribution pattern.
However 3 lenses of 51 designated 2.5
years old, 3 out of 60 designated 3.5 years old and 1 of 44 designated
4.5 years old, fall in the yearling continuous weight distribution
pattern.
236
Comparison of Moose Eye Lens Weights by Sex
and Incisor Cementum Ring Age
Table 3.
1
Age
nM
2
x gms
5
3
nF
x gms
5
4 _
nnMF
5
xgms
-!
32
.3147
21
.3H!5
53
.3162
H
91
.5146
51
.5HlO
142
.5158
2!
36
.6031
15
.5975
51
.6014
3~
48
.6378
12
.6371
60
.6377
4!
32
.6921
12
.6781
44
.6882
5!
21
.7141
10
.7298
31
.7192
6!
10
.7488
9
.7226
19
.7341
7!
12
.7642
5
.7863
17
.7707
8!
13
.7805
3
.7867
16
.7817
9!
7
.7879
9
.7933
16
.7909
lO!
9
.8324
1
.7560
10
.8248
ll!
4
.8300
2
.8025
6
.8208
12!
.8713
1
.8460
6
.8671
13!
5
6
.8539
1
.8786
7
.8574
14!
2
.8'768
2
.8768
1
.8866
1
15!
328
.8866
153
1 By cementun annuli in first incisor
2 Number of males in sample
3 Number of females in sample
4 Total sample both sexes
5 Mean lens weight in grams
481
,
f
I
237
It appears therefore that the age of yearlings and calves can
be determined with a high degree of exactness, solely by the dried
eye lens weight.
Adult moose exhibit a much slower rate of lens
growth as age increases.
data is common.
Hence overlapping of continuous lens weight
There are cases, for example, of a lens from a
6.5 year old moose, whose weight could also fit into the continuous
weight distribution pattern of a 5.5, 4.5 and 3.5 year old animal.
The data from this study support the findings of Simkin which
indicated that lens weight reliably separated calves and yearling
moose.
Overlapping of lens weight in animals older than yearlings
indicated that lens weights appear to have little application as an
exact criterion of age.
238
5314251 80 44 31
19 17 11 18 10 8
6
7
2
1·
.9
.: · · . .
. ·· ~· · .
· ·.
~
•
--
'sampl e
size
I
~
.8
~ .7
.....
-'=
C)
.~
.6
tn
c:
Q)
.5
6_
V
.4
.3
meon - Donom eon.......
Dalo
~
.5 1.5 2 .. 3.5 4.5 5 .. 6.. 7..
a..
95 10.. 11 .. 12.0 135 14.. 15.
Age in Year.
Figure 3.
Eye lens weight distribution related to age.
239
LITERATURE CITED
Cringan, A. T. 1955. Studies of moose antler development in
relation to age. Appendix B, North American Moose by R. L.
Peterson, University of Toronto Press.
Cringan, A. T. 1955.
November, 4pp.
About moose antlers.
Northern Sportsman,
Ellis, R. C. 1972. The impact of management practice on boreal
ecosystems. Projet Program Analysis, Unpublished, Great Lakes
Forest Research Centre Canadian Forestry Service, Sault Ste.
Marie, Ontario.
Lord, R. D., Jr. 1959. The lens as an indicator of age in cottontail rabbits. J. Wildl. Mgmt. 23(3):358-360.
Nunan, P. J. 1965. Moose Weighing Project, Port Arthur District.
Unpublished District Report.
Rowe, J. S.;
Forest Regions of Canada. Canada Department of
Northern Affairs and Natural Resources, Forestry Branch,
Bulletin 123.
Sergeant, D. E., and D. H. Pimlott. 1959. Age determination in
moose from sectioned incisor teeth. J. Wildl. Mgmt. 23(3):315321.
Simard, B. R. 1970. The Moose.
Montreal, Que. 192pp.
National Meat Institute Inc.
Simkin, D. W. 1967. A comparison of three methods used to age moose.
Proc. N. E. Sec. Wildl. Soc., Quebec, P. Q. 13pp.
Timmermann, H. R. 1966, 1968. A study of the moose harvest, Black
Sturgeon area, Port Arthur District. Unpublished District
Report.
Timmermann, H. R. 1971. The Antlers of the Moose, development
related to age. Ontario Fish and Wildlife Review. 10(1-2):
11-18.
Tolmie, K. J. 1967. Black Sturgeon moose checking station.
published District Report.
Un-