Differential Parasitism Between Two Suitable Cowbird Hosts

Differential Parasitism Between Two Suitable Cowbird Hosts

Host choice by the brood parasitic Brown-headed Cowbird (Molothrus ater) is an evolved response to host suitability, resulting in patterns of differential parasitism rates among species within a community. In the ponderosa pine (Pinus ponderosa) forests of the Colorado Front Range, we recorded that Western Wood-pewee (Contopus sordidulus) is infrequently parasitized (1%, n = 259 nests) by the B...

Brown-Headed Cowbird Parasitism of Lazuli Buntings; Relationships with Habitats and Ungulate Hosts

Red-crested cardinal defences against shiny cowbird parasitism

Avian brood parasites reduce the reproductive success of the host, which favours the evolution of antiparasitic defences, such as aggression towards parasites or rejection of their eggs. The red-crested cardinal, Paroaria coronata, is a potential good-quality host of the shiny cowbird, Molothrus bonariensis. However, the frequency of cowbird parasitism in cardinal nests is very low and there ar...

Shiny cowbird Molothrus bonariensis egg size and chick growth vary between two hosts that differ markedly in body size

In birds, egg size aff ects chick growth and survival and it is an important component of reproductive success. Th e shiny cowbird Molothrus bonariensis is an extreme generalist brood parasite that uses hosts with a wide range of body masses. Survival of cowbird chicks decreases with host body mass, as competition for food with nestmates is more intense in large than in small hosts. We studied ...

Brood Parasitism in Asian Cuckoos: Different Aspects of Interactions between Cuckoos and their Hosts in Bangladesh