Appendix A. Values used in simulation model. Two distributions were used: N = normal, B = binomial. YOY = young of the year. ESS = Eastern Scotian Shelf.
Parameter |
Symbol |
Group |
Mean |
Distribution |
SD |
Reference |
Birth rate |
b |
age |
||||
4 |
0.15 |
B |
0.0442 |
Zwanenburg and Bowen 1990 |
||
Hammill and Gosselin 1995 |
||||||
5 |
0.70 |
B |
0.0618 |
Zwanenburg and Bowen 1990 |
||
Hammill and Gosselin 1995 |
||||||
6 |
0.85 |
B |
0.0457 |
Zwanenburg and Bowen 1990 |
||
Hammill and Gosselin 1995 |
||||||
7 |
0.83 |
B |
0.0446 |
Zwanenburg and Bowen 1990 |
||
Hammill and Gosselin 1995 |
||||||
8 |
0.96 |
B |
0.0418 |
Zwanenburg and Bowen 1990 |
||
Hammill and Gosselin 1995 |
||||||
9 |
0.96 |
B |
0.0400 |
Zwanenburg and Bowen 1990 |
||
Hammill and Gosselin 1995 |
||||||
10+ |
0.90 |
B |
0.0202 |
Zwanenburg and Bowen 1990 |
||
Hammill and Gosselin 1995 |
||||||
Density dependence |
θ |
pups, juveniles |
2.4 |
. |
CONSTANT |
Taylor and DeMaster 1993, Harting 2002 |
Proportion on ESS |
||||||
Sable Island population |
m |
quarter |
||||
male |
||||||
1 |
0.66 |
B |
0.0684 |
Austin et al. 2004 |
||
2 |
0.81 |
B |
0.0566 |
Breed and Bowen unpublished data |
||
3 |
0.64 |
B |
0.0693 |
Austin et al. 2004 |
||
4 |
0.75 |
B |
0.0625 |
Breed and Bowen unpublished data |
||
female |
||||||
1 |
0.87 |
B |
0.0476 |
Austin et al. 2004 |
||
2 |
0.76 |
B |
0.0604 |
Breed and Bowen unpublished data |
||
3 |
0.60 |
B |
0.0693 |
Austin et al. 2004 |
||
4 |
0.74 |
B |
0.0620 |
Breed and Bowen unpublished data |
||
YOY |
||||||
1 |
0.92 |
B |
0.0566 |
Austin et al. 2004 |
||
2 |
0.97 |
B |
0.0356 |
Breed and Bowen unpublished data |
||
3 |
0.83 |
B |
0.0783 |
Austin et al. 2004 |
||
4 |
0.93 |
B |
0.0532 |
Breed and Bowen unpublished data |
||
Gulf population |
all |
|||||
1 |
0.39 |
B |
0.0670 |
Hammill unpublished data |
||
2 |
0.29 |
B |
0.0623 |
Hammill unpublished data |
||
3 |
0.01 |
B |
0.0412 |
Hammill unpublished data |
||
4 |
0.08 |
B |
0.0549 |
Hammill unpublished data |
||
Kleiber multiplier |
1+ |
1.7 |
N |
0.55125 |
Sparling and Fedak 2004 |
|
pups |
2.5 |
. |
CONSTANT |
Worthy 1987 |
||
females |
||||||
[summer] |
1.075 |
. |
CONSTANT |
Boily and Lavinge 1995, Beck et al. 2003 |
||
Annual growth |
GR |
male |
||||
(Gompertz parameters) |
p 1 |
52.0 |
N |
285.8 |
Mohn and Bowen 1996 |
|
p 2 |
1.6 |
N |
5.17 |
Mohn and Bowen 1996 |
||
p 3 |
0.2 |
N |
1.45 |
Mohn and Bowen 1996 |
||
female |
||||||
p 1 |
47.8 |
N |
210.3 |
Mohn and Bowen 1996 |
||
p 2 |
1.3 |
N |
4.17 |
Mohn and Bowen 1996 |
||
p 3 |
0.2 |
N |
1.23 |
Mohn and Bowen 1996 |
||
Body mass (kg) |
BM |
male |
||||
(seasonal) |
i = 1 |
241 |
N |
34.8 |
Beck et al. 2003 |
|
i = 2 |
240 |
N |
24.8 |
Beck et al. 2003 |
||
i = 3 |
199 |
N |
37.6 |
Beck et al. 2003 |
||
i = 4 |
291 |
N |
28.8 |
Beck et al. 2003 |
||
female |
||||||
i = 1 |
144 |
N |
15.6 |
Beck et al. 2003 |
||
i = 2 |
160 |
N |
17.8 |
Beck et al. 2003 |
||
i = 3 |
133 |
N |
22.9 |
Beck et al. 2003 |
||
i = 4 |
153 |
N |
13.9 |
Beck et al. 2003 |
||
i = 5 |
207 |
N |
32.9 |
Beck et al. 2003 |
||
pup at weaning |
54.0 |
N |
5.69 |
Boness et al. 1995 |
||
pup at 5 months |
36.8 |
N |
4.37 |
Cooper 2004 |
||
Total body energy (MJ) |
TBE |
male |
||||
(seasonal) |
i = 1 |
3180 |
N |
742.3 |
Beck et al. 2003 |
|
i = 2 |
2956 |
N |
486.8 |
Beck et al. 2003 |
||
i = 3 |
2014 |
N |
760.3 |
Beck et al. 2003 |
||
i = 4 |
3292 |
N |
944.7 |
Beck et al. 2003 |
||
i = 5 |
4460 |
N |
923.8 |
Beck et al. 2003 |
||
female |
||||||
i = 1 |
1729 |
N |
446.1 |
Beck et al. 2003 |
||
i = 2 |
2205 |
N |
428.4 |
Beck et al. 2003 |
||
i = 3 |
1534 |
N |
553.4 |
Beck et al. 2003 |
||
i = 4 |
2030 |
N |
384.2 |
Beck et al. 2003 |
||
i = 5 |
3504 |
N |
724.2 |
Beck et al. 2003 |
||
Energy density of growth |
TBE |
juvenile |
11.38 |
N |
2.78 |
Bowen et al. 1999 |
(MJ/kg) |
||||||
Metabolizable energy |
ME |
0.83 |
N |
0.0482 |
Ronald et al. 1984 |
|
Average energy density |
AE |
quarter |
||||
(kJ/g) |
1, 2 |
5.281 |
N |
0.659 |
Beck et al. submitted |
|
3 |
5.256 |
N |
0.297 |
Beck et al. submitted |
||
4 |
5.465 |
N |
0.349 |
Beck et al. submitted |
||
YOY |
5.345 |
N |
0.483 |
Beck et al. submitted |
||
Proportion cod in diet |
f |
quarter |
||||
male |
||||||
1, 2 |
0.0040 |
N |
0.0842 |
Beck et al. submitted |
||
3 |
0.0000 |
N |
0.0063 |
Beck et al. submitted |
||
4 |
0.0100 |
N |
0.0591 |
Beck et al. submitted |
||
female |
||||||
1, 2 |
0.0040 |
N |
0.0333 |
Beck et al. submitted |
||
3 |
0.0450 |
N |
0.1635 |
Beck et al. submitted |
||
4 |
0.0150 |
N |
0.0716 |
Beck et al. submitted |
||
YOY |
0.0858 |
N |
0.1839 |
Beck et al. submitted |
||
Proportion cod at age in diet |
p |
age |
||||
1 |
0.3410 |
B |
0.0463 |
This study |
||
2 |
0.3437 |
B |
0.0475 |
|||
3 |
0.2173 |
B |
0.0500 |
|||
4 |
0.0759 |
B |
0.0530 |
|||
5 |
0.0185 |
B |
0.0603 |
|||
6 |
0.0030 |
. |
CONSTANT |
|||
7 |
0.0004 |
. |
CONSTANT |
|||
8 |
0.0001 |
. |
CONSTANT |
|||
LITERATURE CITED
Austin, D., W. D. Bowen, and J. I. McMillan. 2004. Intraspecific variation in movement patterns: modeling individual behaviour in a large marine predator. Oikos105:15–30.
Beck, C. A., W. D. Bowen, and S. J. Iverson. 2003a. Seasonal energy storage and expenditure in a phocid seal: evidence of sex-specific trade-offs. Journal of Animal Ecology 72:280–291.
Boily , P., and D. M. Lavigne. 1995. Resting metabolic rates and respiratory quotients of grey seals ( Halichoerus grypus) in relation to time of day and duration of food deprivation. Physiological Zoology 68:1181–1193.
Boness , D. J., W. D. Bowen, and S. J. Iverson. 1995. Does male harassment of females contribute to reproductive synchrony in the grey seal by affecting maternal performance? Behavior, Ecology and Sociobiology 36:1–10.
Bowen, W. D., D. J. Boness, and S. J. Iverson. 1999. Diving behaviour of lactating harbour seals and their pups during maternal foraging trips. Canadian Journal of Zoology 77:978–988.
Cooper, M. H. 2004. Fatty acid metabolism in marine carnivores: implications for quantitative estimation of predator diets. PhD Thesis. Dalhousie University, Halifax, Nova Scotia.
Hammill , M. O., and J. F. Gosselin. 1995. Grey seal ( Halichoerus grypus) from the Northwest Atlantic: female reproductive rates, age at first birth, and age of maturity of males. Canadian Journal of Fisheries and Aquatic Sciences 52:2757–2761.
Harting, A. L. 2002. Stochastic simulations model for the Hawaiian monk seal. PhD Thesis. Montana State University, Bozeman, Montana, USA.
Mohn , R., and W. D. Bowen. 1996. Grey seal predation on the eastern Scotian Shelf: modelling the impact on Atlantic cod. Canadian Journal of Fisheries and Aquatic Science 53:2722–2738.
Ronald, K., K. M. Keiver, F. W. H. Beamish, and R. Frank. 1984. Energy requirements for maintenance and faecal and urinary losses of the grey seal ( Halichoerus grypus). Canadian Journal of Zoology 62:1101–1105.
Sparling , C. E., and M. A. Fedak. 2004. Metabolic rates of captive grey seals during voluntary diving. Journal of Experimental Biology 207:1615–1624.
Taylor, B. L., and D. P. DeMaster. 1993. Implications of non-linear density dependence. Marine Mammal Science 9:360–371.
Worthy, G. A. J. 1987. Metabolism and growth of young harp and grey seals. Canadian Journal of Zoology 65:1377–1382.
Zwanenburg , K. C. T., and W. D. Bowen. 1990. Population trends of the grey seal ( Halichoerus grypus) in eastern Canada. Pages 185–197 in W. D. Bowen, editor. Population biology of sealworm ( Pseudoterranova decipiens) in relation to its intermediate and seal hosts. Canadian Bulletin of Fisheries and Aquatic Sciences, No. 222, Ottawa.