Gourmand New Caledonian crows munch rare escargots by dropping


Numerous broken shells of a rare endemic snail Placostylus fibratus, a species rated as vulnerable, were scattered around rocky beds of dry creeks in rainforest of New Caledonian. We set a video camera near one site to identify the predator. We recorded a New Caledonian crow Corvus moneduloides dropping and consuming the snail. This is the first direct evidence of the crow dropping of this native species. The assumed weight of snails relative to the crow is exceptionally heavy among prey dropped by birds.

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We are grateful to all the staff of the Syndicat Mixte des Grandes Fougères, particularly Henri Bloc, Philippe Guichard, Selelino Keletaona, and Yoann Kawa, for their indulgent support for our field investigations. We thank our laboratory members for their help, particularly the sparrow project group for lending apparatus. We are grateful to Véronique Monjo and Kentaro Takagi for useful comments. The study was aided by funds from the Japan Society for the Promotion of Science Grant no. 23255004 (Grant-in-Aid for Basic Research A; KU), 24770028 (Grant-in-Aid for Young Scientists B; KDT), and Research Fellowships (DC2: 24-4578; NJS), and from the Polish National Science Centre, grant no. NCN 2012/05/E/NZ8/02694 (JT).

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Correspondence to Keita D. Tanaka.

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Y. Okahisa and N.J. Sato are JSPS Research Fellows (DC2).

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Tanaka, K.D., Okahisa, Y., Sato, N.J. et al. Gourmand New Caledonian crows munch rare escargots by dropping. J Ethol 31, 341–344 (2013). https://doi.org/10.1007/s10164-013-0384-y

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  • New Caledonian crow
  • Prey dropping
  • Land snail
  • Foraging economics