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1.
At the Calakmul Biosphere Reserve in Campeche, Mexico, the prey spectra of sympatric jaguars (Panthera onca) and pumas (Puma concolor) were studied by examination of their scats. 10 vertebrate species were identified for jaguars and 7 for pumas, mainly mammals and some birds. Based on these diet analyses, we conclude that jaguars and pumas coexist at Calakmul by means of different food habits.  相似文献   

2.
There is a great need to develop efficient, noninvasive genetic sampling methods to study wild populations of multiple, co‐occurring, threatened felids. This is especially important for molecular scatology studies occurring in challenging tropical environments where DNA degrades quickly and the quality of faecal samples varies greatly. We optimized 14 polymorphic microsatellite loci for jaguars (Panthera onca), pumas (Puma concolor) and ocelots (Leopardus pardalis) and assessed their utility for cross‐species amplification. Additionally, we tested their reliability for species and individual identification using DNA from faeces of wild felids detected by a scat detector dog across Belize in Central America. All microsatellite loci were successfully amplified in the three target species, were polymorphic with average expected heterozygosities of HE = 0.60 ± 0.18 (SD) for jaguars, HE = 0.65 ± 0.21 (SD) for pumas and HE = 0.70 ± 0.13 (SD) for ocelots and had an overall PCR amplification success of 61%. We used this nuclear DNA primer set to successfully identify species and individuals from 49% of 1053 field‐collected scat samples. This set of optimized microsatellite multiplexes represents a powerful tool for future efforts to conduct noninvasive studies on multiple, wild Neotropical felids.  相似文献   

3.
4.
This paper reports the growth status of a sample of Mopan Maya school children living in a rural village in Belize. These children exhibit a growth pattern typical of chronic undernutrition, in that a high percentage are stunted (66%), but virtually none are wasted by WHO criteria. The Belize Maya children are compared to four other Amerindian groups and found to be shorter and lighter than a semi-urban group from Guatemala, but taller and heavier than three rural groups from Guatemala and Mexico. The Belize children exhibit the largest arm circumferences among all five groups. This pattern of growth is discussed in light of current ideas concerning the contribution of genetics vs. environment to childhood growth and population wellbeing. © 1994 Wiley-Liss, Inc.  相似文献   

5.
The Belize atolls—Glovers Reef, Lighthouse Reef and Turneffe Islands—show differences in geomorphology, lagoonal depth, bottom sediment, growth of mangroves and sea-grass, exposure to waves and currents as well as in their sedimentation rates and their age. Bivalve shell assemblages in lagoonal areas reflect these geomorphological differences. On each atoll, 32 to 44 recent sediment samples were taken (total number of samples 111) and bivalve shells subsequently identified. The resulting database (32,122 bivalve shells in total) was analysed using Q-mode cluster analyses. Both the distribution of species characteristic of different lagoonal habitats and the distribution of bivalves with different life and feeding habits were investigated. Epifaunal suspension feeders were found particularly on hard-bottom along the reef-crests or clinging to mangrove roots. Infaunal suspension feeders show a more diverse distribution. Deeper lagoonal parts and areas with mangrove growth are often inhabited by chemosymbiont-carrying bivalves, indicating locations of reduced sediment. Deep burrowing detritus feeders are very abundant in shallow-water areas with moderate to high water agitation and were seldom found in Halimeda-rich sediments.  相似文献   

6.
Women of Belize: Gender and Change in Central America. Irma McClaurin. New Brunswick, NJ: Rutgers University Press, 1996.218 pp.  相似文献   

7.
Jaguars Panthera onca inhabiting tropical or subtropical evergreen moist forest have often been classified as opportunistic predators because they consume prey relative to its availability. However, these studies failed to address simultaneously the distribution of predator and prey through time and space, which may lead to an incomplete or erroneous understanding of jaguar foraging strategies. In this study, we reconstructed jaguar diet from scat, and used camera traps to investigate jaguar prey availability and the distribution of jaguar and its prey through space and time. We focused our examination of predator–prey temporal and spatial relations on forest infrastructure comprising man-made paths, small mammal trails, tapir Tapirus bairdi trail and trail-less, forested areas as they represent distinct habitats for prey selection. Overall, we observed high overlap between the prey used and available, suggestive of opportunistic foraging. However, jaguars exhibited selective tendencies in discriminating between larger prey. Jaguars used collared peccary Tayassu tajacu greater than its availability, while preying upon the equally abundant and similarly distributed white-lipped peccary Tayassu pecari and tapir less than predicted based upon availability. Armadillo Dasypus novemcinctus and paca Agouti paca , 56.6% of total consumption, were consumed relative to availability but exhibited low spatial overlap with jaguar. Armadillo and paca used trail-less, forested areas and small mammal trails not used by jaguar and were photographed more frequently at greater distances from man-made paths, major thoroughfares for jaguars. This study suggests that although forest jaguars use prey relative to its abundance, jaguars may rely on foraging strategies other than chance encounters for exploiting prey.  相似文献   

8.
Two forest associations, cohune palm (Cohune Ridge) and mixed tropical hardwood (High Bush), were assessed on the basis of nutrient movement and storage for their suitability for agriculture. Continuous monitoring of soil nitrogen and leaf litterfall over a one-year period provided information on soil building processes in the forest fallow. Destructive cuts revealed the storage of 690 kg N ha–1 in the standing biomass of the Cohune forest versus 203 kg N ha–1 in the High Bush. Litter biomass was exceptionally high in the Cohune Ridge (497 kg ha–1 dry matter) as compared to the High Bush (65 kg ha–1 dry matter) and other tropical forests. This is probably because of a low rate of decomposition in the Cohune Ridge palm forest. A substantial reserve of nitrogen is present in both forests' fallows, and this can in part be harvested by the small farmer for crop production.
Ciclo de nitrógeno en la zona de bosque seco estacional de Belize, América Central
Resumen Dos asociaciones boscosas (Palma Cohune y Matorral Alto) se estudiaron en relación a sus reservas y flujos de nutrimentos y sus posibilidades de aprovechamiento agricola. Se siguió la evolución del nitrógeno en el suelo y en la caida de hojarasca durante un año obteniéndose asi información sobre los procesos pedogenéticos en el barbecho del bosque.A través de muestreos destructivos se encontró que en la biomasa del bosque de Palma Cohune habían 690 kg N ha–1 y en el Matorral Alto solo 203 kg N ha–1. La biomasa de hojarasca era excepcionalmente alta en Palma Cohune alcanzando un valor de 497 kg materia seca ha–1; en el bosque de Matorral Alto la hojarasca era de 65 kg materia seca ha–1. Esto probablemente se deba a la baja velocidad de descomposición en el caso de la palma.Las reservas sustanciales encontradas en ambos barbechos para el nitrógeno podrían ser parcialmente utilizadas para la producción agrícola campesina.
  相似文献   

9.
Halophila baillonii Ascherson was found in Belize, Central America in 2003 and 2005. The observation extends the known range of this seagrass species to the western Caribbean. H. baillonii was previously recorded only in the eastern Caribbean and at one Pacific site in Panama. Both fruits and flowers of H. baillonii were observed at two locations in Belize in 2005. H. baillonii in Belize is an important food for manatee, forms a productive seagrass-based ecosystem, and is adversely affected by shoreline development and watershed run-off.  相似文献   

10.
Scarlet Macaw diet was determined during the breeding season of February–June 1998. Macaws were primarily granivorous, exhibiting a narrow diet during the dry season, with low variety of food items in adult and nestling diets. Seeds of Cnidoscolus spp. and Schizolobium parahybum, tree species characteristic of floodplain forest, were predominant in nestling diets, and may provide protein‐rich food resources. River floodplains provided important nest sites and food resources for Scarlet Macaws during the breeding season.  相似文献   

11.
The Cockscomb Basin Wildlife Sanctuary, Belize was established in 1986 following Rabinowitz and Nottingham's 1986 study on jaguar diet and distribution. In 2002, we reexamined jaguar diet following two decades of mitigated human hunting of jaguar prey. We observed high overlap between historical and current jaguar diet constructs. Nine‐banded armadillo remained the most frequently consumed prey item. However, collared peccary consumption increased by nearly 20 percent while dietary breadth decreased by 60 percent presumably reflecting increased prey availability following reduced human hunting pressure.  相似文献   

12.
Tree species diversity was measured in a network of very small galleryforests within the Mountain Pine Ridge savanna in Belize. Research focussed onforest patches smaller than 1 ha in size (micro-forests) and linearstrips of trees along creeks lacking interior core zones with low understoreylight levels (tree thickets). Twenty-five micro-forests and 51 tree thicketsites were sampled throughout the savanna. A total of 144 morphospecies 5cm dbh (106 in micro-forests and 117 in tree thickets) werefound, which represents 1/5 of the approximately 700 native tree species in Belize.Most (85.3%) of the species encountered are typically found in tropical rainforests and few are restricted to savanna or riparian environments. Speciesaccumulated at a much faster rate in micro-forests than in tree thickets. Onlyone species, the palm Acoelorraphe wrightii, was extremelyabundant, accounting for almost 30% of all stems. Many of the species werepresent in very low densities: 19% of all species found in micro-forests and 42%of those found in tree thickets had on average one or fewer stems per hectare. Alarge proportion of species were also found infrequently across the landscape,being present in only 36% of micro-forests and at 52% of tree thicket sites. Theresults indicate that networks of very small forest patches can contain highnumbers of species and could therefore contribute to the maintenance of regionalbiodiversity.  相似文献   

13.
The marine tubificid oligochaete fauna of Belize is the most diverse that has been described for the Caribbean Sea, with records for over 50% of all known Caribbean species. Tubificids were sampled at 77 stations around the outer barrier of the coral reefs off the Belize mainland. A total of 1,529 individuals representing 52 species were collected. Species distribution patterns were controlled mainly by sediment type and the presence or absence of mangroves. Six species (Phallodrilus molestus, Tubificoides bermudae, Inanidrilus leukodermatus, Heterodrilus flexuosus, Bathydrilus formosus, Smithsonidrilus hummelincki) with diverse life history characteristics were common and had broad habitat preferences being found in various types of heterogeneous sandy sediments. Heterodrilus flexuosus was the only common species in these samples known only in Belize. The other five common species range from Belize to Florida or Bermuda. Most other species have narrower habitat preferences and are limited to specific habitats. For example, one group of gutless species was restricted to organically enriched fine to medium sands, a group of Limnodriloidinae occurred only in mud around mangrove cays, and a group of meiofaunal species were restricted to saline groundwater.  相似文献   

14.
Sedges from genus Eleocharisdominate extensive wetlands in the sugar cane growing areas of the Caribbean. Correlative data suggest that macrophytes in these wetlands are phosphorus limited. To determine effects of increased P input that can be expected, e.g. from agricultural runoff, a common sugar cane fertilizer was applied to representative plots in four marl-based and four peat-based marshes. The plots were located in the proximity of patches of Typha domingensis, which has been reported to be able to outcompete Eleocharis under nutrient rich conditions. Responses to the fertilizer treatment were documented as changes in: Plant height, density, biomass, net primary production, nutrient resorption, decomposition, plant and soil nutrient concentrations, percent cover of cyanobacterial mats, and potential colonization by Typha. Additions of phosphorus significantly increased plant density and height and, consequently, the aboveground net primary production. Phosphorus resorption efficiency following senescence was independent of fertilizer addition in Eleocharis but decreased in Typha from the fertilized plots. Phosphorus resorption proficiency was lower in fertilized plots for both Typha and Eleocharis. Decomposition of litter and cellulose assays was significantly faster in fertilized plots. No spontaneous establishment of Typha occurred in the fertilized plots, but survival of transplanted Typha was higher in fertilized plots than in controls. Increased plant density in fertilized plots led to elimination of a key component of these ecosystems, the nitrogen fixing cyanobacterial mats.  相似文献   

15.
Calder  Dale R. 《Hydrobiologia》1991,216(1):221-228
Qualitative and quantitative collecting was undertaken in 1987 to determine the species composition, abundance, and distribution of hydroids in a mangrove system at Twin Cays, Belize. Of 49 species identified, the 5 most frequent were Ventromma halecioides, Nemalecium sp., Clytia hemisphaerica, Dynamena crisioides and Halopteris diaphana. Line-transect census data and qualitative observations showed that the hydroid fauna was sparse in sheltered, still-water areas of the mangal, but relatively abundant and diverse in areas exposed to waves and/or tidal currents. Species composition and relative abundance varied with depth at stations in exposed locations and in tidal creeks and channels. Although Turritopsoides brehmeri is known only from Twin Cays at present, it seems improbable that any of the species is restricted to mangrove ecosystems.  相似文献   

16.
Sruoga V  Puplesis R 《Zoological science》2003,20(10):1273-1277
Stephensia armata sp. n., a remarkable species is described from Belize (Central America). The external features and genitalia of the male are figured and described in detail. A distribution map for all six Elachistidae species, currently recorded from tropical America, is given: Perittia smaragdophanes (Meyrick), P. punatensis Kaila, Elachista albisquamella Zeller, E. saccharella (Busck), E. vasrana Kaila and Stephensia armata Sruoga, sp. n.  相似文献   

17.
Seven benthic foraminiferal assemblages were identified in vibracores through Holocene lagoons of three Belize atoll lagoons (Glovers Reef, Lighthouse Reef, Turneffe Islands). These include (1) the low-diversity Cribroelphidium assemblage (2) the Cribroelphidium-Elphidium assemblage (3) the Quinqueloculina-Triloculina-Peneroplis assemblage (4) the high-diversity miliolid assemblage (5) the Archaias-miliolid assemblage (6) the low-diversity miliolid assemblage, and (7) the mixed assemblage. Altogether, 109 species and 56 genera were identified. The highest diversities are observed in the largest lagoon (Turneffe Islands), whereas one of the smaller lagoons (Glovers Reef) exhibits the lowest diversities during the Holocene. No significant changes in diversity over time occur, however, a slight trend to higher diversity may be observed through the Holocene, suggesting that the foraminiferal faunas in the atolls are in a diversification stage. Faunal diversity in atoll lagoons appears to be controlled largely by habitat size, habitat heterogeneity, and water circulation. Habitat age and water depth only play minor roles. Substrate texture, water depth, and turbidity influence the predominant modes of life of benthic foraminifera encountered in the lagoons (epifaunal versus infaunal versus symbiont-bearing). Time-averaging effects were not observed, even though lagoonal sedimentation rates fluctuate in individual cores and the three lagoons, and despite the fact that sediments are modified through bioturbation by callianassid shrimps. This finding underlines the potential of benthic foraminifera for paleoecological studies in the fossil record of reefs and carbonate platforms.  相似文献   

18.
19.
Two new species are described from the tropical forest of Belize: Coptotriche singularis (host-plant unknown) and C. forsteroniae (leaf-miner on Forsteronia myriantha, Apocynaceae). The external features and male genitalia are figured and described for both species. A checklist of Coptotriche species comprising 31 species currently known from the Americas is given. Most of the species are known from mainland USA and Canada, and only a few from the Neotropics (the Caribbean and Belize).  相似文献   

20.
Cyanobacterial mats, widely distributed in the inland alkaline marshes of northern Belize and other regions in the Caribbean, are not only important and functionally complex components of these habitats, but they are also significant reservoirs of biological diversity. Highly diverse and (relatively) isolated marshes have provided conditions suitable for cyanoprokaryotic organisms and conditioned the adaptation and stabilization of numerous specialized eco‐ and morphotypes. Species richness of cyanobacteria assemblages follows the conductivity gradient and is highest in the marshes of medium conductivity (c. 1000–2000 µS cm?1) and decreases at low (< 500 µS cm?1) and high (> 3000 µS cm?1) conductivities. This ecologically unique cyanobacterial microflora is very sensitive to nutrient enrichment, both directly and indirectly through shading by expanding macrophytes. Species richness of cyanobacterial assemblages decreases dramatically as a result of eutrophication. Similar cyanobacterial communities are widely distributed in limestone‐based areas of Florida, Central America and Caribbean but none of them is currently under any legal protection status. The purpose of this paper is to bring attention to an ecologically important group of organisms that have traditionally not been considered in species diversity evaluations or conservation efforts.  相似文献   

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