Geology topics

Chris Wemmer

Publications and source records attributed to Chris Wemmer.

3 recordsLinked to original sources

USGS1991

Rehabilitation of a Species: The Black-Footed Ferret (Mustela nigripes)

Black-footed ferrets ( Mustela nigripes ) are an endangered carnivore endemic to North America. This small nocturnal member of the weasel family is totally dependent on the prairie dog ( Cynomys spp.) ecosystem for survival. The ferret lives in prairie dog burrows and relies on prairie dogs for 90 percent of its diet (3,21). Poisoning of prairie dogs was largely responsible for the 98 percent reduction in geographic distribution of prairie dogs; concurrently, black-footed ferret numbers plummeted. Recently, only a single known population of black-footed ferrets remained. In 1985 that popuation, located near Meeteetse Wyoming, succumbed to an outbreak of canine distemper, and the few remaining ferrets were taken into captivity in an attempt to save the species through captive progation.

Conference Paper↗

USGS1990

Development of survival skills in captive-raised Siberian polecats ( Mustela eversmanni ) I: locating prey

Captive-raised mustelids appear to have a rudimentary capacity to kill prey, but the skills necessary for locating prey may be eroded during captivity. We tested the maturational component of prey-searching behavior with captive-raised Siberian polecats ( Mustela eversmanni ) by subjecting polecats to a simulated prairie dog colony of 6 burrows within a 200 m 2 arena. Ten naive Siberian polecats at ages 2.5, 3.5, and 4.5 months (30 total) were deprived of food for 12 hours. A dead prairie dog was placed in 1 prairie dog burrow and the other 5 were empty. A single Siberian polecat was released onto the colony shortly before sunset and its movements monitored from an observation tower. Older Siberian polecats located prey significantly quicker than younger polecats, but all age groups spent a great deal of time in surface activity not directed toward a burrow. When Siberian polecats were about 10 months old, all burrows in the arena were plugged with dirt including the burrow with the prairie dog. In this winter test, Siberian polecats located the prey but still spent a great deal of time in non-burrow directed surface activity. Economical use of surface time, with a low amount of non-burrow directed behavior, would presumably reduce the risk of predation for hunting polecats.

Journal of Ethology↗

USGS1990

Development of survival skills in captive-raised Siberian polecats ( Mustela eversmanni ) II: predator avoidance

We exposed naive Siberain polecats ( Mustela eversmanni ) (aged 2, 3, and 4 months) to a swooping stuffed great horned owl ( Buho virginianus ) and a stuffed badger ( Taxidae taxus ) mounted on a remote control toy automobile frame. The first introduction to each was harmless, the second was accompanied by a mild aversive stimulus, the third (1 day after attack) was harmless, and the fourth (30 days after attack) was harmless. Alert behavior increased after a single attack by either predator model. Escape responses of naive polecats did not differ between ages when exposed to the badger, but 4 month old polecats reduced their escape times after a single badger attack. When exposed to the swooping owl, naive 4 month old polecats redponded more quickly than the other two age groups, and 3 and 4 month old polecats reduced escape times after a single owl attack. This indicates an innate escape response to the owl model at 4 months of age, and a short-tert ability to remember a single mild aversive encounter with the badger and owl models at 3 or 4 months of age.

Journal of Ethology↗