Behavior and Ethology Commons^™

Sandhill Crane Roost Selection, Human Disturbance, And Forage Resources, Aaron T. Pearse, Gary L. Krapu, David A. Brandt

USGS Northern Prairie Wildlife Research Center

Sites used for roosting represent a key habitat requirement for many species of birds because availability and quality of roost sites can influence individual fitness. Birds select roost sites based on numerous factors, requirements, and motivations, and selection of roosts can be dynamic in time and space because of various ecological and environmental influences. For sandhill cranes (Antigone canadensis) at their main spring staging area along the Platte River in south-central Nebraska, USA, past investigations of roosting cranes focuse donphysical channel characteristics related to perceived security as motivating roost distribution.We used 6,310 roost sites selected by 313 sandhill cranes over …

Differential Wolf-Pack-Size Persistence And The Role Of Risk When Hunting Dangerous Prey, Shannon M. Barber-Meyer, L. David Mech, Wesley E. Newton, Bridget L. Borg

USGS Northern Prairie Wildlife Research Center

Risk to predators hunting dangerous prey is an emerging area of research and could account for possible persistent differences in gray wolf (Canis lupus) pack sizes. We documented significant differences in long-term wolf-pack-size averages and variation in the Superior National Forest (SNF), Denali National Park and Preserve, Yellowstone National Park, and Yukon, Canada (p < 0.01). The SNF differences could be related to the wolves’ risk when hunting primary prey, for those packs (N = 3) hunting moose (Alces americanus) were significantly larger than those (N = 10) hunting white-tailed deer (Odocoileus virginianus) (F1,8 = 16.50, p = 0.004). Our data support the hypothesis that differential pack-size persistence may be perpetuated by differences in primary prey riskiness to …

Patuxent’S Long-Term Research On Wolves, L. David Mech

USGS Northern Prairie Wildlife Research Center

The gray wolf (Canis lupus) was one of the first species placed on the Endangered Species List in 1967. The Endangered Species Act of 1973 legally protected the wolf along with other listed species.

Patuxent Wildlife Research Center (Patuxent) in Laurel, MD, began its Endangered Wildlife Program in 1966, and U.S. Fish and Wildlife Service (USFWS) biologist Ray Erickson was assigned to lead it. In 1973, I was transferred to the program from Region 3 of the USFWS, having been employed there since 1969 to study wolves in Minnesota.

Endangered Species Act protection of the wolf fostered its quick …

Wolf (Canis Lupus) Generation Time And Proportion Of Current Breeding Females By Age, L. David Mech, Shannon M. Barber-Meyer, John Erb

USGS Northern Prairie Wildlife Research Center

Information is sparse about aspects of female wolf (Canis lupus) breeding in the wild, including age of first reproduction, mean age of primiparity, generation time, and proportion of each age that breeds in any given year. We studied these subjects in 86 wolves (113 captures) in the Superior National Forest (SNF), Minnesota (MN), during 1972–2013 where wolves were legally protected for most of the period, and in 159 harvested wolves from throughout MN wolf range during 2012–2014. Breeding status of SNF wolves were assessed via nipple measurements, and wolves from throughout MN wolf range, by placental scars. In …

Territoriality And Inter-Pack Aggression In Gray Wolves: Shaping A Social Carnivore's Life History Rudyard Kipling's Law Of The Jungle Meets Yellowstone's Law Of The Mountains, Kira A. Cassidy, Douglas W. Smith, L. David Mech, Daniel R. Macnulty, Daniel R. Stahler, Matthew C. Metz

USGS Northern Prairie Wildlife Research Center

When Rudyard Kipling wrote The Jungle Book in 1894 and included the famous line "For the strength of the Wolf is the Pack, and the strength of the Pack is the Wolf," he would have had no idea that over a century later, scientific research would back up his poetic phrase. Recent studies in Yellowstone have found that both the individual wolf and the collective pack rely on each other and play important roles in territoriality. At a time when most fairy tales and fables were portraying wolves as demonic killers or, at best, slapstick gluttons, Kipling seemed to have …