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Providing evidence to improve practice

Individual study: Cross-fostering in Gray Wolves (Canis lupus lupus)

Published source details

Scharis I. & Amundin M. (2015) Cross-fostering in Gray Wolves (Canis lupus lupus). Zoo Biology, 34, 217-222


This study is summarised as evidence for the intervention(s) shown on the right. The icon shows which synopsis it is relevant to.

Place captive young with captive foster parents Terrestrial Mammal Conservation

A replicated study in 2011 in six zoos in Sweden and Norway (Scharis & Amundin 2015) found that grey wolf Canis lupus lupus pups placed with foster parents in captivity had higher survival rates but weighed less than pups that stayed with their biological mother. After 32 weeks, more fostered cubs survived (75%) than cubs that remained with their biological mother (65%). At 24–26 days age, fostered cubs weighed less (1,337 g) than cubs that remained with their biological mother (2,019 g). In 2011, eight pups born at zoos were removed from their biological mothers at 4–6 days of age. Pups were microchipped, to allow identification, given fluids to reduce dehydration, and transported by car or plane to new zoos. Foster pups were placed in litters containing 7–10 pups. On arrival, the tails of foster pups were rubbed in the urine of other pups so that they smelled similar. A total of 35 pups stayed with their biological mother. Cameras were placed at the den of each litter. Pups were weighed at irregular intervals and all deaths recorded.

(Summarised by Phil Martin)