Study

Supplementary food is taken by Californian condors Gymnogyps californianus and may increase reproductive output

  • Published source details Wilbur S.R., Carrier W.D. & Borneman J.C. (1974) Supplemental feeding program for California condors. The Journal of Wildlife Management, 38, 343-346

Actions

This study is summarised as evidence for the following.

Action Category

Provide supplementary food for vultures to increase adult survival

Action Link
Bird Conservation

Provide supplementary food for vultures to increase reproductive success

Action Link
Bird Conservation
  1. Provide supplementary food for vultures to increase adult survival

    A study in California, USA, between February 1971 and May 1973 (Wilbur et al. 1974) found that Californian condors Gymnogyps californianus fed on at least 47 of 83 carcasses provided over the study period. Another 27 carcasses may well have been fed on and the remaining nine were taken by black bears Ursus americanus before condors could feed. Carcasses were mainly mule deer Odocoileus hemionus. This study is also discussed in ‘Provide supplementary food to increase reproductive success’.

     

  2. Provide supplementary food for vultures to increase reproductive success

    A small before-and-after study in California, USA, between February 1971 and May 1973 (Wilbur et al. 1974) found that three Californian condors Gymnogyps californianus were raised during the study period, compared to only one in the preceding three years. The authors suggest that the only substantial difference between the two time periods was the presence of the feeding station, supplied with approximately one carcass a week, normally of mule deer Odocoileus hemionus. The authors note that a longer study would be needed to confirm to role of feeding in reproductive success. This study is also discussed in ‘Provide supplementary food to increase adult survival’.

     

Output references

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