habitats

HABITAT SEGREGATION OF DENGUE VECTORS ALONG AN URBAN ENVIRONMENTAL GRADIENT

Cox, J, Grillet, ME, Ramos, OM, Ammador, M, et al. Habitat
segregation of dengue vectors along an urban environmental
gradient. Am J Trop Med Hyg 2007; 76:820–826.

Abstract: 
Differential distributions of Aedes aegypti and Ae. mediovittatus (potential inter-epidemic dengue vector) and other mosquitoes colonizing bamboo pots in San Juan, Puerto Rico were studied along an urban-rural gradient. City regions (urban, suburban, and rural) and landscape elements within regions (forest [F], low-density housing [LDH], and high-density housing [HDH]) were identified using satellite imagery. Aedes species extensively overlapped in LDH of urban, suburban, and rural areas. Mosquito species showed their high specificity for landscape elements (96.6% correct classification by discriminant analysis); absence of Ae. mediovittatus in HDH or absence of Ae. aegypti in forests were the main indicator variables. The gradient was explained using a canonical correspondence analysis, which showed the association of Ae. aegypti with HDH in urban areas, Culex quinquefasciatus with LDH in suburbs, and Ae. mediovittatus and other native mosquitoes (Cx. antillummagnorum, Toxorhynchites portoricencis) with less disturbed habitats (forests, LDH).

Factors Influencing Tropical Island Freshwater Fishes: Species, Status, and Management Implications in Puerto Rico

Neal JW, Lilyestrom CG, Kwak TJ (2009) Factors influencing tropical island freshwater fishes: species, status, and management implications in Puerto Rico. Fisheries 37:546-554

Abstract: 
Anthropogenic effects including river regulation, watershed development, contamination, and fish introductions have substantially affected the majority of freshwater habitats in Europe and North America. This pattern of resource development and degradation is widespread in the tropics, and often little is known about the resources before they are lost. This article describes the freshwater resources of Puerto Rico and identifies factors that threaten conservation of native fishes. The fishes found in freshwater habitats of Puerto Rico represent a moderately diverse assemblage composed of 14 orders, 29 families, and 82 species. There are fewer than 10 species of native peripherally-freshwater fish that require a link to marine systems. Introductions of nonindigenous species have greatly expanded fish diversity in freshwater systems, and native estuarine and marine species (18 families) also commonly enter lowland rivers and brackish lagoons. Environmental alterations, including land use and development, stream channelization, pollution, and the impoundment of rivers, combined with nonnative species introductions threaten the health and sustainability of aquatic resources in Puerto Rico. Six principal areas for attention that are important influences on the current and future status of the freshwater fish resources of Puerto Rico are identified and discussed.

Quantitative Assessment of Habitat Preferences for the Puerto Rican Terrestrial Frog, Eleutherodactylus coqui

Beard, Karen H.; Mccullough, Sarah; Eschtruth, Anne K. 2003. Quantitative Assessment of Habitat Preferences for the Puerto Rican Terrestrial Frog, Eleutherodactylus coqui. Journal of Herpetology, Vol. 37, No. 1, :10-17,.

Abstract: 
We conducted a quantitative analysis of adult and juvenile Eleutherodactylus coqui (coquí) habitat preferences in Puerto Rico. The analysis consisted of two surveys: one to quantify potential habitat and another to quantify habitat use. Coquís were found to use most habitats available to them; however, adults and juveniles preferred different plant species, habitat structural components, and heights from the forest floor. Adult and juvenile coquís had opposite associations with many important plant species in the forest (e.g., Prestoea montana and Heliconia carabea) and habitat structural components. Adults had a negative association with leaves and a positive association with leaf litter. Juveniles showed the opposite trend. Adults were more evenly distributed with respect to height than were juveniles, with adults preferring heights around 1.1 m and juveniles preferring heights closer to the forest floor. The quantitative survey technique for determining habitat preferences used in this study generally confirmed coquí habitat preferences known from qualitative assessments.
Syndicate content