Occurrence of Feather Mites (proctophyllodidae) among Birds of Ventura County Lowlands, California

Abstract

During 1977 through 1988, an examination of 90 species of birds, totalling 47,326 individuals in and near Camarillo, Ventura County, California, established the distribution and seasonality of feather mites (Proctophyllodes spp.) on these hosts.The House Finch (Carpodacus mexicanus) was the most abundant permanent resident examined and showed peak feather mite infestations in March and September.The White-crowned Sparrow (Zonotrichia leucophrys) was the most abundant winter resident studied, arriving in September or October with few evident mites which increased to a peak in March-April.Summer resident species were fewer in number with lighter mite loads.When all birds are considered the peak year of infestation at the park was 1982 whereas at the house it was 1983.Circadian movements at dusk and other factors controlling the distribution and numbers of the mites are discussed.INCIDENCIA DE PIOJOS (PROCTOPHYLLODIDAE) EN AVES DEL CONDADO DE VENTURA, CALIFORNIA Rcsumcn.--Dcsdccl 1977 hasta cl 1988 sc cxaminaron 90 cspccics dc aves y un total dc 47,326 individuos cn y ccrca dc Camarillo (Condado dc Ventura, California) y sc cstablcci6 la distribuci6n y estacionalidad de piojos (Proctophyllodidae) en sus hu6spedes.Carpodacus mexicanus fuc la especie rcsidcntc m{s abundantc y mostr6 picos de infecci6n de piojos en marzo y scpticmbrc.Zonotrichia leucophrys fuc la cspccic rcsidcntc m{s abundantc cn cl invicrno, 11cgando al {rca dc cstudio cn scpticmbrc u octubrc con algunos piojos, los quc aumcntaron hasta alcanzar un pico cn marzo-abril.Las cspccics rcsidcntcs cn cl vcrano tuvicron 25% mcnos piojos.Las aves dc parqucs tuvicron una infccci6n m{xima cn cl 1982, micntras quc las cspccics cascras lo fucron cn cl 1983.En cstc trabajo son discutidos movimicntos circadianos al oscurcccr y otros factorcs quc controlan la distribuci6n y nfimcro de piojos. World-wide collection of birds during the 18th and 19th centuries stimulated an early interest in their ectoparasites (Trousseart 1886).Feather mites were considered innocuous, however, and not listed as potential disease vectors until Boyd (1951).The shift in interest to mites as possible disease vectors stimulated Atyeo, his staff, and students to revise several genera (Atyeo and Braasch 1966, Orwig 1968).Earlier Dubinin published several papers (1950, 1951, 1952, 1953, 1956) in Russian which reported on his comprehensive studies of mites.In 1600 pages Dubinin addressed many of the problems of feather mite dispersion both on individual hosts and within species.Gaud (1957) from France also reported on feather mites.My study in Ventura County, California, from 1977 to the present, has focused on the interrelationships between mites and their hosts.The impact of annual bird populations, host migration, and seasonality upon mite infestations is examined.Mites infesting individual hosts were followed to determine how rapidly the parasite population could expand or decline.