Treesearch

The Cattle Egret (Bubulcus ibis) was first reported in the Greater Caribbean Basin from Old Providence Island in 1933. It was not reported again from the region until 1944, when an individual was sighted in Aruba, Southern Netherlands Antilles. Within 4 years, the species was reported in Puerto Rico and Jamaica more than 800 km north of Aruba in the Greater Antilles. By 1957, Cattle Egrets were successfully nesting in nearby Cuba and St. Croix. Today, the species is known from more than 50 major islands throughout the Caribbean Basin. Cattle Egrets show strong dispersal tendencies and...

The knowledge of the ways in which insects disperse is important in decisions concerning their control. The dispersal of insects aided by the wind cannot be regarded as accidental and occasional but as an adaptive feature of the phylum (Johnson and Bowden 1973). Due to its location, Puerto Rico is exposed to cyclone winds that can affect the colonization and abundance of insects. In this work I present an overview of tropical cyclones on insect dispersal, the recorded arrival of insects during cyclone events, and the effects of tropical cyclones on insect abundance in Puerto Rico.

Aspects of the Cattle Egret's reproductive ecology and habitat use in an insular environment were studied on Montserrat, West Indies. Average size of 290 nests (17.9 cm) was smaller than sizes reported in the literature and was attributed to a paucity of available nesting materials. We measured 330 eggs to determine: egg volume (24,117.04 mm3), fresh egg weight (24.4 g), egg weight loss during incubation (2.9 g), pipping egg ("star pips" only) weight (21.5 g), egg length (45.56 mm), egg breadth (32.22 mm), and a speciesspecific egg weight constant Kw (= 0.506) (where Kw is fresh egg weight...

ln response to A. Marguerite Baumgartner's request for information on the phenomenon of sex reversals in wild birds "Sex Reversal in Banded Cardinal" (North American Bird Bander 11(1|:11, 19861 I would like to report a similar e_xperience and a plausible explanation offered by Dr. Kenneth Parkes of the Carnegie Museum, pittsburgh, Pennsylvania.

Periodic disturbances caused by hurricanes constitute an integral phase of forest growth and development in the Caribbean region. The 35-year recovery in seven permanent plots in the Colorado Forest of the Luquillo Mountains in Puerto Rico covering the 14 through 49 year period after a major disturbance was characterized by: (1) ingrowth and mortality rates of 20 stems/ha/yr, or 1.1% yr of the initial number of stems; (2) shifts to larger tree diameters and heights; (3) a 3% decline in the number of trees in the intermediate and dominant crown classes and a 6% increase in the number of...

The causes of bill deformities in birds have been summarized in an excellent review by Pomeroy (Brit. Birds 55:49-72, 1962). Causes include genetic mutations, disease, accident, poor nutrition, and, in caged birds, an absence of bill-filing substrates (e.g., stones, coarse bark). In wild birds, however, bill deformities are most often associated with injury to the bill. Easterla and Todd (Auk 88: 677•678, 1971) reported such an apparent injury in a free-living Yellow-headed Blackbird {Xanthocephalus xanthocephalus} from Clay County, Missouri. The blackbird apparently had suffered a...

Pathogenesis of myiasis due to the muscid fly Philornis decepttous in nestling pearlyeyed thrashers (Margurops fuscatus) in the Luquillo Rain Forest, Puerto Rico was investigated. Philornid larvae penetrated the host integument, underwent a period of development and growth, and established, as third instar larvae, between the dermis and the body musculature. Movement into this location plus growth and development of the fly larva appeared to be linked to the ingestion of host tissues including red blood cells, mononuclear cells which infiltrated from focal accumulations adjacent to the...

Growth rates varied little among unparasitized (normally developing) Pearly eyed Thrasher nestlings. Botfiy ectoparasitism, however, significantly retarded growth and development in parasitized young. Parasitized nestlings showed different growth patterns at various ages, depending on the timing of the initial parasitic attack and the extent of larval infestation. Nestling growth was most affected within the first 1.5 weeks after hatching, the period of maximum growth rate in 4 of 5 sampled growth characters (body mass, culmen, ulna, tarsus). The ninth primary feather showed accelerated...

A rain-forest population of the Pearly-eyed Thrasher (Margarops fuscatus) suffered heavy ectoparasitism from the larvae of a tropical fly recently identified as Philornis deceptivus. The impact of parasitic attack was of less consequence to adult thrashers than to nestlings. Nestling mortality was high and was caused mostly by philomid ectoparasitism, other factors being negligible (3%). The extent of larval infestations fluctuated seasonally and was related to monthly rainfall. Infestation did not have to be heavy to cause debilitation and death. Larval infestation sites varied with the...