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Skip to Search Results- 4Derocher, A.E.
- 3Andrew E. Derocher
- 3Mark A. Lewis
- 2Derocher, A. E.
- 2Derocher, Andrew E.
- 2Stirling, I.
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A body composition model to estimate mammalian energy stores and metabolic rates from body mass and body length, with application to polar bears
Download2009-01-01
Derocher, Andrew E., Klanjscek, Tin, Molnár, Péter K., Lewis, Mark A., Obbard, Martyn E.
Many species experience large fluctuations in food availability and depend on energy from fat and protein stores for survival, reproduction and growth. Body condition and, more specifically, energy stores thus constitute key variables in the life history of many species. Several indices exist to...
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1999
We observed a case of adoption of a single four-month-old polar bear cub (Ursus maritimus) into an existing litter of two cubs on Hopen Island, Svalbard. We believe the high density of maternity dens in the study area may increase the likelihood of natural adoption. Speculation about theoretical...
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2007
A case of polar bear infanticide and cannibalism is reported from Phippsøya, Svalbard. In this instance, a cub of some 7 months was killed by an adult male bear, which was in poor condition, in the close proximity of the mother,which was also in poor condition. It seems probable that the attack...
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2016-01-01
Marie Auger-Méthé, Mark A. Lewis, Andrew E. Derocher
Home range size estimates are often used to assess the amount of space required for animals to perform the activities essential for their survival and reproduction. However, in moving environments, traditional home range estimates may be ill suited to this task. In particular, traditional home...
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1999
Two instances of infanticide and cannibalism in polar bears (Ursus maritimus) were observed in SE Svalbard, at Hopen Island. In the first, an adult male killed three young cubs at a den site and consumed one of them. In the second, an adult male actively pursued, killed, and consumed a dependent...
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2019-01-01
Jody R. Reimer, Marc Mangel, Andrew E. Derocher, Mark A. Lewis
Animals must balance a series of costs and benefits while trying to maximize their fitness. For example, an individual may need to choose how much energy to allocate to reproduction versus growth, or how much time to spend on vigilance versus foraging. Their decisions depend on complex...
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1993
If climatic warming occurs, the first impacts on polar bears (Ursus maritirnus) will be felt at the southern limits of their distribution, such as in James and Hudson bays, where the whole population is already forced to fast for approximately four months when the sea ice melts during the summer....
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2009
Belikov, S. E., Maslanik, J., Aars, J., Born, E. W., Amstrup, S. C., Serreze, M. C., Stirling, I., Wiig, O., Nielson, R. M., DeWeaver, E., Durner, G. M., Bailey, D. A., McDonald, T. L., Mauritzen, M., Holland, M. M., Derocher, A. E., Douglas, D. C.
Projections of polar bear (Ursus maritimus) sea ice habitat distribution in the polar basin during the 21st century were developed to understand the consequences of anticipated sea ice reductions on polar bear populations. We used location data from satellite-collared polar bears and...
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2010
Thiemann, G. W., Molnár, P. K., Derocher, A. E., Lewis, M. A.
Polar bear (Ursus maritimus) populations are predicted to be negatively affected by climate warming, but the timeframe and manner in which change to polar bear populations will occur remains unclear. Predictions incorporating climate change effects are necessary for proactive population...