An experimental evaluation of food hoarding by North Island robins ( Petroica australis longipes )
|Title||An experimental evaluation of food hoarding by North Island robins ( Petroica australis longipes )|
|Publication Type||Journal Article|
|Year of Publication||2005|
|Authors||Alexander, L, Duthie, C, Fyfe, J, Haws, Z, Hunt, S, Montoya, I, Ochoa, C, Siva, A, Stringer, L, Horik, JV, Burns, KC|
|Type of Article||paper|
|Keywords||competition, experiment, Food hoarding, North Island robin, Petroica australis|
We experimentally evaluated the food hoarding behaviour of North Island robins (Petroica australis longipes) at Karori Wildlife Sanctuary, Wellington. Mealworms were offered to free-ranging pairs of male and female robins to evaluate whether their food hoarding behaviour was similar to previous observations of South Island robins. We also tested theoretical predictions derived in the Northern Hemisphere, which argue that competitively subordinate birds should hoard more food than dominant birds. Results showed that the food hoarding behaviour of North Island robins was similar to South Island robins, except that North Island robins repeatedly used the same cache sites, which is rare in South Island robins. Data did not support the prediction that competitively subordinate birds hoard more food than dominant birds. Males acquired most of the mealworms offered to birds during trials, and won nearly all aggressive interactions observed between sexes. Therefore, males appeared to be competitively dominant to females in winter. However, males stored over five times as many mealworms as females, which is opposite to theoretical predictions. We interpret the reluctance of females to cache food as a strategy to avoid food loss to competitively dominant males.