The strong and the hungry: bias in capture methods for mountain hares Lepus timidus
Authors: Bisi, Francesco; Newey, Scott; Nodari, Mosè; Wauters, Lucas A.; Harrison, Annabel; Thirgood, Simon; Martinoli, Adriano
Source: Wildlife Biology, Volume 17, Number 3, September 2011 , pp. 311-316(6)
Publisher: Nordic Board for Wildlife Research
Abstract:Estimating density, age and sex structure of wild populations is a key objective in wildlife management. Live trapping is frequently used to collect data on populations of small and medium-sized mammals. Ideally, sampling mammal populations by live capturing of individuals provides a random and representative sample of the target population. Trapping data may, however, be biased. We used live-capture data from mountain hares Lepus timidus in Scotland to assess sampling bias between two different capture methods. We captured hares using baited cage traps and long nets on five study areas in the Scottish Highlands. After controlling for the effects of body size, individuals caught in traps were lighter than individuals caught using long nets, suggesting that the body condition of hares differed between the capture methods. This tendency may reflect an increased risk-taking of individuals in poorer body condition and less aversion to entering traps in order to benefit from eating bait. Overall, we caught more adult hares than juveniles and more female hares than males. Our results show that estimates of density and population structure of mountain hares using livecapture data could be affected by the capture method used. We suggest that live-capture studies employ more than one capture method and test for heterogeneity in capture probability to minimise potential bias and achieve reliable estimates of population parameters.
Document Type: Research Article
Publication date: September 2011
- WILDLIFE BIOLOGY was initiated in 1994 by the Nordic Council for Wildlife Research (NKV) and is published four times a year (March, June, September and December). Wildlife Biology is sponsored by NKV, and the National Environmental Research Institute (NERI), Kalø, is responsible for the technical production.
WILDLIFE BIOLOGY is a high-quality scientific forum directing concise and up-to-date information to scientists, administrators, game managers and conservationists.
- Editorial Board
- Information for Authors
- Subscribe to this Title
- ingentaconnect is not responsible for the content or availability of external websites