Treesearch

Two Elevations-above 800m and above 300m- define the montane forests of the caribbean islands. Of the 36 islands considered, 27 have mountains above 300m and 14, above 800m. of the 233,000 km2 of the island, at least 118,000 km2 are above 300m m, and 60,000 km2 are above 800 m.

We studied avian resource use in a native West Indian pine (Pinus occidentalis) forest in the Cordillera Central of the Dominican Republic during the nonbreeding season. The forest is characterized by a fairly open pine canopy and a dense mixed-broadleaf and pine understory. We used a principal components analysis of 23 foraging characters for 23 bird species, including foraging height, the proportional use of 5 different foraging methods, 3 horizontal positions and foliage densities, and 11 foraging substrates. Five principal components accounted for 74 percent of the total variance of...

Long-tcrm smdif's are needed to undersrand rhc dynamics of tropical forests, particularly those subject to pcriodic disturbances such as hurricanes. We studied a flood plain Prestoea montana palm forest in the Luquillo Mountains of Puerro Rico over a 15-yr period (1980-1995), which included the passage of Hurricane Hugo in September 1989. The passage of the hurricane caused the dominant species to become more dominant and created low instamaneous rree morrality (1 o/o of stems) and reductions in tree biomass (-16 Mg/ha/yr) and density, although not in basal area. Five years after the...

Responding to near total deforestation in Puerto Rico , in the 1920's the U.S. Department of Agriculture, Forest Service, began to produce tree seedlings, reforest degraded lands, establish planting trials, and conduct silvicultural research. In 75 years an extensive body of knowledge has been accumulated. Advances in tree-seed handling , nursery practice, plantation establishment , and plantation management made in Puerto Rico are summarized. Tree species recommended by local research and experience for planting in wildland, farm, and urban forestry are detailed in this report. Site...

This paper is a brief summary of the natural history and importance of the insects of Puerto Rico. We briefly discuss the orders of insects present in Puerto Rico and some of their families. Where possible, we have tried to avoid technical terms for better comprehension of a general audience. We present the observations or characteristics of insects that humans admire. Our intent is that this paper serve as an introduction for students, teachers and those with interest in insects and maybe motiviate some of them to dedicate themselves to the study of this group of animals that is so...

Although Camponotus ustus Forel, originally described from St. Thomas, now a part of the American Virgina Islands, has been long considered common in Puerto Rico, we found that such specimens are misidentified and actually represent two distinct species, both previously undescribed. These are described herein as C. kaura and C. taino. Based on the types and additional material from Mona Island, we have redescribed C. ustus. The following new synonymy is proposed: C. ustus = C. ulysses Forel = C. furnissi Wheeler and Mann = C. sublautus Wheeler and Mann = C. depolitus Wheeler = C. larvigerus...

The venom alkaloids from the workers of nine collections of Solenopsis (Diplorhoptrum) from California contain either (5E,9E)-3-hexyl-5- methylindolizidine (Ic) or (SZ,9E)-3-hexyl-5-methylindolizidine (Id) along with cis-2-methyl-6-nonylpiperidine. The structures of these compounds were determined from their mass spectra and by comparison of their GC-FTIR spectra with those of a synthetic mixture. In view of the facts that a third diastereomer of 3-hexyl-5-methylindolizidine had been reported in previous collections of Solenopsis (Diplorhoptrum) queens from Puerto Rico, and that indolizidin...

We studied microhabitat use, foraging and social behavior of Broad-billed (Todus subulatus)a nd Narrow-billed (T. angustirostrisT) odies in two areaso f sympatry in the Cordillera Central of the Dominican Republic. Solitary Broad-billed and Narrow-billed Todies occupied distinct microhabitats in both shade coffee plantations and native pine forest while generally sharing similar foraging strategies. In both habitats, Broad-billed Todies foraged higher in the vegetation and occurred in more outer horizontal positions with lower foliage density than did their congener. Movement rates and...