Study ID 308

Powdermill Nature Reserve monitored small mammal populations from 1979-1999.

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Realm: Terrestrial
Climate: Temperate
Biome: Temperate broadleaf and mixed forests
Central latitude: 40.170741
Central longitude: -79.260178
Duration: 21 years, from 1979 to 1999

35398 records

14 distinct species

Across the time series Peromyscus maniculatus is the most frequently occurring species


Merritt, J. (1999) Long Term Mammal Data from Powdermill Biological Station 1979-1999. Environmental Data Initiative. Available at:, accessed 2016.


Density of small mammals (numbers/ha) were estimated by direct enumeration methods on a 1 ha live trapping grid consisting of a 10 X 10 quadrat of trap stations at 10-m intervals. Trapping was conducted bimonthly from September 1979 to October 1999. Two large Sherman live-traps (7.6 X 8.9 X 30.5 cm) containing synthetic fiber nesting material and sunflower seeds as bait were located at each station. Trapping shelters were used at each station to monitor subnivean activity of mammals during winter months. Upon capture. small mammals were ear tagged or toe clipped for identification; at first capture. number. location on grid. mass. sex and reproductive status were recorded. Animals were weighed to the nearest 0.5 g using a Pesola scale and classified as adult. subadult or juvenile according to body mass and sexual maturity. Position of the testes (either abdominal or scrotal) was used to describe reproductive condition of males. Reproductive status of females was assessed by noting condition of the vulva (whether perforate or not perforate) and nipples (whether small. medium or lactating). Upon recapture during the same period. the number. location and mass was recorded and the animal released. quadrat Unit of abundance = IndCountInt, Unit of biomass = Weight