Treesearch

Abundance of the Puerto Rican Vireo (Vireo Zutimeri) in Guanica Forest, Puerto Rico, has declined gradually over the period 1973-1996 as determined by constant effort mist netting. Concurrent studies of breeding vireos show low nesting success, primarily due to parasitism by Shiny Cowbirds (Molothrus bonariensis). This decline may reflect the rather recent entry of the cowbird into Guanica Forest during the breeding season, as other factors (vegetation change, rainfall) do not seem to explain the decline. As a single island endemic, it is important that the cause of this decline be...

Pterocarpus officinalis Jacq., called palo de pollo in Puerto Rico, bloodwood in Guyana and Panama, and by numerous other names throughout its extensive range, is an evergreen tree that reaches 40m in height

The proliferation of degraded tropical landscapes in need of rehabilitation and the reduction of primary forest area have forced a closer collaboration between ecologist and land manager. this collaboration has led to new paradigms of forest management (combined in the term ecosystem management), new insight into forest ecology through comparative ecological functioning of these ecosystems.

Point counts and mist nets were used to sample birds in sun and shade coffee plantations, and remnant pine forests in an agricultura! region of the Cordillera Central, Dominican Republic from Jan.-Feb. 1992 to 1994. Rarefaction analysis indicated that species richness was highest in pine and lowest in plantations. Species diversity (H') was similar in point counts in the three habitats, but an "overdominance" was evident in net samples in shade coffee where the two most cornrnon species constituted 51% of all captures in contrast to 37% in pine and 27% in sun coffee. Pine forest had more...

We determined the flocking propensity of 48 species of birds occurring in native pine forest in the Cordillera Central of the Dominican Republic, and the species composition of 180 mixed-species flocks. Flocks were unusually ubiquitous, with 46 species occurring in at least one flock, 11 species regularly present, and all insectivorous species and all migrant species participating. Most birds encountered were permanent residents, but winter residents (Nearctic migrants) were an important component of the flocks and, as a group, had the highest flocking propensity. Flocks were cohesive and...