The agonistic and sexual functions of vocalizations of male brown-headed cowbirds, Molothrus ater

The significance of sound interception to males of the bicolor damselfish,Pomacentrus partitus, during courtship

“…To prevent the loss of, or to gain a possible spawning partner, the interceptor should move directly to the sound source, as has been shown in frogs (Wells 1977, Fellers 1979, and cowbirds (Rothstein et al 1988), and then attempt to prevent mating. Sexual interference has been observed among many animal groups, e.g., insects (Waage 1973), reptiles (Martin 1984), amphibians (Arnold 1976, Wells 1977, Fellers 1979, Verrell 1984, 1988, and mammals (Cox & LeBoeuf 1977, Wirtz 1981, Hauser 1990).…”

Acoustic mate copying: female cowbirds attend to other females' vocalizations to modify their song preferences

“…Brown-headed cowbirds (Molothrus ater) are gregarious songbirds that have been the subject of a large number of examinations of female preferences for male vocalizations (King & West 1983;King et al 1986;Rothstein et al 1988;O'Loghlen & Rothstein 2004). What benefits females gain from having preferences is unclear.…”

Status and management of neotropical migratory birds

“…During point-counts, cowbirds heard giving their distinctive "rattle" call should be recorded separately from those giving other calls. The rattle call is usually given by females (Rothstein et al 1988), whereas the other two calls are primarily or exclusively given by males. Because cowbirds have a strongly male-biased sex ratio (Rothstein et al 1986, Yokel 1989, many males present in nest-searching areas are likely to be unmated and may be searching for mates rather than nests.…”

“…The cowbird egg-laying period genernlly extends from mid-April until mid-July (Friedmann 1929, Scott 1963, which also coincides with the majo~ period of egg-laying in most neotropical migrants ). Resident and short-distance migrants genernlly have longer breeding seasons that only partially overlap that of the cowbird.…”