A New Species of Extinct Oryzomyine Rodent From the Quaternary of Curaçao, Netherlands Antilles

An extinct new species of Oryzomyine rodent, known since 1936 from the cave of Grot van Hato on the island of Curaçao, is described from abundant new specimens collected from owl-pellet deposits at three localities on the island

Los Roques and Las Aves archipelagos, Venezuela: A marine ecological and conservation reconnaissance of two little-known southeastern Caribbean oceanic archipelagos

The Los Roques and Las Aves oceanic coral reef archipelagos of Venezuela lie in a biogeographically unique and biologically diverse area of the Caribbean and possess extensive coral reefs, seagrass beds, mangroves and shallow macroalgae meadows. The geographic location of these archipelagos safeguards them from most Western Atlantic hurricane damage as well as the most severe Caribbean coral bleaching episodes. While the Aves islands remain uninhabited and are an area of low accessibility, Los Roques has been a managed national park since 1972. We here present an updated synthesis of recent research for these archipelagos as an aid to scientists and conservationists interested in these island groups for which no recent ecological reviews are available. Los Roques has been much better documented than Las Aves and is the largest coral reef marine protected area of Venezuela. It has about 1,500 inhabitants living principally from tourism and fisheries. Studies show that Los Roques possesses fish populations that suffer comparatively less fishing pressure and may serve as a rare benchmark for pristine fish communities elsewhere in the Caribbean. It has also successfully maintained its importance to seabird colonies for the last five decades, notwithstanding serious marine park funding and staffing shortages. A new baseline biological inventory for Las Aves is particulary critical considering the fragmentary information available for this archipelago. The relatively intact and resilient oceanic coral reef systems of Los Roques and Las Aves are of regionally significant conservation value and deserve much more conservation and biodiversity attention than so far accorded.</p

Nutrients and anti-nutrients in leaf litter of four selected mangrove species from the Sundarbans, Bangladesh and their effect on shrimp (Penaeus monodon, Fabricius, 1798) post larvae

The release of nutrients and anti-nutrients from mangrove leaf litter plays an important role in the biogeochemical cycling in aquatic environments and directly or indirectly affects water quality and food availability to shrimp. In this study, we assessed nutrient and anti-nutrient loss during decomposition of leaf litter at a concentration of 1 g/L for four mangrove species (Avicennia officinalis, Heritiera fomes, Sonneratia apetala, Sonneratia caseolaris) to monitor water quality and to estimate how leaf litter influences shrimp post larvae (PL) growth and survival. There were significant differences (P < 0.05) between the studied species in terms of mass loss of the leaf litter during the investigation period. There were also significant differences (P < 0.05) between the studied species in terms of loss of nutrients and anti-nutrients in the shrimp PL rearing tank during the four-week experimental period. Decomposing mangrove leaves stimulated availability of natural food for shrimp PLs. There was a strong positive correlation between mass loss and PL production. At the concentrations of leaf litter used, the anti-nutritional factors did not affect the PLs. PL survival with mangrove leaf litter was 75–82%, whereas all the PL died without any leaf litter. PL weight gain ranged from 0.83–3.33 mg/d where S. apetala leaf litter resulted in the highest PL growth rate, followed by A. officinalis, S. caseolaris and H. fomes, in that order (P < 0.05). Overall, mangrove leaf litter had a positive effect on shrimp performance in terms of growth and survival and this effect was highest for S. apetala leaf litter.</p

The butterflies of St. Eustatius with faunal comparisons among the adjacent islands of the Lesser Antilles

Based on four years of butterfly monitoring in four contrasting natural habitats on St. Eustatius, we document large and consistent differences in the butterfly species assemblages in the different habitats and compare the butterfly assemblages of the three windward Dutch islands to those of other islands of the Lesser Antilles. Seven new species records were established for St. Eustatius, thereby updating the butterfly list to a total of 32 species. Pieridae were the most numerically abundant group of butterflies (48%), followed by Lycaenidae (26%), Hesperiidae (12%), and smaller numbers of both Heliconiinae (6%) and Charaxinae (5%). Heliconiinae and Charaxinae both showed a significant dependence on the moister, wind-sheltered habitats of the volcanic slopes and crater of the Quill, but this dependence was particularly strong for Heliconiinae. The butterfly faunas of the windward Dutch islands numbered a total of 44 species. The presence of larval host plants needed for local reproduction was confirmed for all but two species. Cluster analysis separated the butterfly faunas of these and the surrounding islands into two groups. The more speciose butterfly assemblages of Saba, St. Eustatius, and St. Martin clustered together with the those of the surrounding higher islands of Antigua, Montserrat, Nevis, and St. Kitts, while the poorer faunas of the low-lying islands of Anguilla, St. Bartholomew, and Barbuda formed a separate cluster and had a lower species richness particularly in the Heliconiinae and Charaxinae. Based on consistent effects of elevation on butterfly faunas, at both geographic scales (between areas on St. Eustatius and between islands), our results suggest that island maximum elevation is the overriding factor explaining the distribution of butterfly faunal richness in the northern Lesser Antillean islands studied

Synergistic effects of mangrove leaf litter and supplemental feed on water quality, growth and survival of shrimp (Penaeus monodon, Fabricius, 1798) post larvae

Shrimp based mangrove-aquaculture (silvo-aquaculture) is practiced in many countries of the world and leaf litter of different mangrove tree species is a potential nutrient source in these systems. The present study evaluated the effects of mangrove leaf litter from four mangrove species (Sonneratia apetala, S. caseolaris, Avicennia officinalis and Heritiera fomes) on the production of juvenile shrimp (Penaeus monodon) with and without supplemental feed. Fifteen-day-old post larvae (PL15) with an average weight of 0.01 g were reared in 1100 L fibre-reinforced polyethylene tanks containing 1000 L of 10 ppt saline water and a water depth of 0.9 m. Leaf litter with or without supplemental feed was applied to the tanks according to a 4 × 2 factorial design. The PLs were stocked at a density of 100 per tank and the experiment was conducted for 4 weeks without any exchange of water. Both mangrove species and feed application affected shrimp performance and water quality parameters except dissolved oxygen (DO), chemical oxygen demand (COD) and zoo-plankton concentration. The average survival rate of juvenile shrimp ranged from 86 to 94% in the treatments with both leaf litter and feed, 75–82% in the treatments with only leaf litter and 88% in the treatment with only feed. However, 100% mortality was observed in the treatment without any leaf litter or supplemental feed. Combined, leaf litter and feed resulted in 21 to 33% higher weight gain of shrimp PL than based on the combined contributions of leaf litter only or feed only, indicating synergism. Among the different mangrove species, S. apetala (23.1%) contributed the highest to total weight gain followed by A. officinalis (21.6%), S. caseolaris (21.6%) and H. fomes (10%). The lower feed conversion ratio (FCR) (0.18–0.27) in the treatments combining leaf litter and supplemental feed as compared to the feed-only treatment (0.41) indicated that leaf litter (directly or by stimulating natural food production) contributed to supplemental feeding. The growth of phytoplankton also appeared to contribute in low FCR as evidenced by a positive correlation (P < 0.001, r = 0.681⁎⁎) between phytoplankton concentration and shrimp weight gain. The synergistic effect between leaf litter and supplemental feed can help the farmer to minimize the shrimp production cost by lowering the feed input and enhancing mangrove three coverage on pond dikes as an inexpensive source of natural food

Appendix A. Description of the spatial simulation model.

Description of the spatial simulation model