© 1967 by The Society for Integrative and Comparative Biology
Some Aspects of the Population Ecology of Wolves, Alaska
Alaska Department of Fish and Game Fairbanks, Alaska
Information on Alaskan wolf populations was obtained from examination of bounty records, 4,150 wolf radii and ulnae, 1,262 wolf carcasses, and from observations of wolves inhabiting an area of 20,000 square miles where wolves were protected.
Pregnant adult female wolves averaged 6.5 fetuses; two-year-old females averaged 5.3 fetuses;female pups were not sexually mature.
In Alaska, wolves conceive from late February through early April but most females breed in March. Multiparous females breed earlier than first breeders. Multiparous females produce an average of 7.3 ova and 6.5 implanted fetuses. The loss of ova from ovulation to implantation is significant. Multiparous females produce more ova than first breeders; the difference is highly significant.
Mortality of pups rather than the lack of initial production of pups is believed to be the reason for the observed variations in the proportion of pups in wolf populations. Wolf packs include members in all categories of sex and age during the breeding season. Size of the pack is an indicator of abundance.
Wolves in an area where they were protected increased at an average rate of 20–30% per year during an 11-year period.