American Cliff Swallow (Petrochelidon pyrrhonota) Science Article 6
abstract
For two consecutive years 24 hours or more of continuous precipitationduring early June resulted in mortality in nestlingT ree Swallows{ Iridoprocnebicolor} and Cliff Swallows {Petrochelidonp yrrhonota} in Marin County,California. There have been few reports of swallow nestling mortality caused byinclement weather in North America. Chapman (1955) reported abandoned eggsand death of nestling Tree Swallows at Princeton, Massachusetts in 1940.Paynter (1954) reported Tree Swallow nests with abandoned eggs due to astorm on 8-9 June at Kent Island, Wisconsin. Druty (1959) reported massnestling mortality due to continuous rain from 12-20 June in Massachusett
Robert M. Stewart, Calif. Birds 3: 69-70, 1972