Advantages and disadvantages of coloniality in the swallow, Hirundo rustica

Publication Type:Journal Article
Year of Publication:1987
Journal:Animal Behaviour
Date Published:1987
ISBN Number:0003-3472
Keywords:Hirundinidae, Hirundo, Hirundo rustica
Abstract:The advantages and disadvantages of coloniality in swallows, Hirundo rustica, were studied in 1971-1975 and 1977-1985. Nest sites were not limiting the local population density, and swallows tended to aggregate actively at specific sites. Colony size was positively correlated with local food abundance and the amount of lee for prevailing westerly winds. The amount of food per individual swallow decreased with colony size, and nestling feeding rates were lower for colonial than for solitary swallows. Social foraging effects, measured as individual feeding success in relation to the number of simultaneously foraging conspecifics, were not important. Extra-pair copulations and chases of female swallows by male nonmates of the colony were common in colonies. The percentage of time males spent mate guarding, the frequency of intraspecific nest parasitism and the percentage of time spent nest guarding during egg laying increased with colony size. Infanticide by unmated males occurred more frequently in larger colonies, being an important mortality factor. Mite infection causing nestling mortality and change of nest sites between first and second clutches increased with colony size. Nest predation averaged only 1
Short Title:Animal Behaviour
Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith