On 27 September 2014, while taking videos from a hide at the Riet Vell bird reserve in the Ebro Delta, northeastern Spain, I observed an adult Purple Swamphen (Porphyrio porphyrio) feeding on insects trapped in some spiders’ webs. The webs were hanging from reedmace (Typha sp.) bordering a shallow lagoon and the bird was climbing up some dry reed bases of the same plants to reach the insects, picking them out one by one deliberately (see video ). Although mainly vegetarian, the Purple Swamphen is regarded as omnivorous, with insects forming a small proportion of its diet (Rodríguez & Hiraldo 1975, Cramp & Simmons 1979, Taylor 1996), but I am unaware of any accounts on this peculiar way of procuring insects.
References
Carroll, A.L.K. (1966). Food habits of the Pukeko (Porphyrio melanotus, Temminck). Notornis 13: 133–144.
Rodríguez, R. & Hiraldo, F. (1975). Régimen alimenticio del Calamón (Porphyrio porphyrio) en las marismas del Guadalquivir. Doñana Acta Vertebrata 2: 201–213.
Taylor, B. (1996). Purple Swamphen (Porphyrio porphyrio). In: del Hoyo, J., Elliott, A. & Sargatal, J. (eds.). Handbook of the Birds of the World. Vol. 3. Hoatzin to Auks. Lynx Edicions, Barcelona.