8 research outputs found
Comparison of grouper assemblages in northern areas of the wider Caribbean: A preliminary assessment
Groupers (Pisces: Serranidae) are important top-level predators in wider Caribbean, but have experienced significant exploitation, resulting in declines in abundance, size, spawning aggregations, and changes in species composition. Larger groupers are particularly vulnerable to intense fishing because of their longevity, slow growth, delayed reproduction, and aggregate spawning. Marine fishery reserves (MFR), areas permanently closed to consumptive use, offer a viable means to protect grouper resources. This study reports on fishery-independent surveys of groupers in four regions of the tropical western Atlantic during 1995 - 1997: Florida Keys, central Bahamas, southeastern Cuba, and Dominican Republic. The regions surveyed included two national parks and a national marine sanctuay, and were further categorized as: 1) intensively fished with little or no management for groupers (Cuba, Dominican Republic); 2) intensively fished with gear and effort limitations (Florida Keys); 3) lightly fished with some management (N. and S. Exuma Cays, Bahamas); and 4) a. MFR closed to fishing since 1986 (Exuma Cays Land and Sea Park, Bahamas). From 10 - 20 strip transects (20 m x 5 m) were surveyed in shallow-water (l-20 m depth) hard-bottom habitats for grouper species composition, density, and size distribution. Nine grouper species (6 Epinephelus spp., 3 Mycteroperca spp.) were documented among all regions. Areas in which groupers were partially or wholly protected from fishing had greater grouper diversity, density, and biomass, particularly for targeted species such as Nassau grouper (E. striatus). Classification of groupers by three size classes (small, intermediate, large) indicated a distinct gradient from areas with intense fishing to the MFR. In three of the regions affected by intense fishing, one of which has several grouper fishery regulations, grouper abundance and biomass were dominated by non-targeted species such as the graysby (E. cruentatus) and coney (E. fulvus). This second-order effect of fishing probably indicates competitive or predation. MFRs represent a viable means to protect grouper resources, alleviating the complications of enforcement and partially the need to gather fisheries dependent data. The ability of groupers to recover in certain regions may be deterred because of reduced larval recruitment from upstream, heavily fished sources
Density, species, and size distribution of groupers (Serranidae) in three habitats at Elbow Reef, Florida Keys
We examined the density, size and species distribution of groupers in three habitats on an inshore-to-offshore transect across Elbow Reef, Florida Keys: high-relief spur-and-groove (4–9 m depth), relict spur-and-groove (10–20 m), and deep fore reef slope (21–30 m). Physical relief was greatest in the high-relief spur-and-groove (up to 3 m), lowest in the relict spur-and-groove habitat (30%). There were significant differences in the density, size, and species distribution of groupers among the three habitats. Graysby, Epinephelus cruentatus, was numerically dominant, constituting 82–91% of individual observed. Black grouper, Mycteroperca bonaci, and Nassau grouper, E. striatus, were more abundant in high to moderate relief habitats, whereas red hind, E. guttatus, was more abundant in the low-relief habitat. The size distribution was shifted towards smaller sizes in lowest relief habitat and towards larger sizes in areas with greater (\u3e0.5 m) vertical relief. We suggest that fishing pressure in the Florida Keys has resulted in an offshore grouper assemblage dominated by graysby, a small grouper species (length) which is not targeted by fishermen, and that habitat selection and biological interactions have significantly influenced the ecological structure of the grouper assemblage of this coral reef
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Will Miami survive? the dynamic interplay between floods and finance
This SpringerBrief uses a complexity perspective to integrate risk, finance, and ecological issues in Miami, USA. It focuses on how the modern financial system, particularly the mortgage market, perceives and manages the risk of climate change. Authors Kathleen Sealey, Ray King Burch and P.-M. Binder offer the case study of South Florida to illustrate how landscapes can be either re-purposed to function ecologically when residents relocate or rebuilt to reduce the threat of future flooding, the tools needed to make these decisions, and how financial systems view and influence them. While the need to integrate financial markets into coastal (and environmental) management is increasingly recognized, the difficulty of this task is made greater by the speed of financial innovation and the obscurity and complexity of its practices. This book will discuss the innovative Southeast Florida Regional Climate Compact, and the success of public-private partnerships in planning and adapting to sea level rise, but also the broad disconnect with the cash-and-credit-driven real estate market of South Florida. The book presents an interdisciplinary approach to the understanding of the coupled human (including finance) and natural systems in coastal cities, thus breaking new ground in the approach towards sustainability research and education. The final chapter introduces the social component of resilience which include pre-disaster outreach with and the potential for decision theory to help people understand and manage risk.
Analysis of a volunteer method for collecting fish presence and abundance data in the Florida Keys
A roving diver fish survey method that requires relatively little time and equipment was developed for use by trained volunteer divers to regularly, rapidly, and inexpensively document patterns of reef fish distribution and abundance, In this method, a diver searches a dive site and records all observed fish species and their abundance in log10 categories, Results from 130 h of observation were analyzed from three regional surveys conducted in the Florida Keys at a total of 27 reefs by four observers during the summer of 1994. The Upper Keys had the most species (166) followed by the Lower Keys (151) and the Dry Tortugas (142). More uncommon species were found in the Dry Tortugas. Experienced volunteer divers were able to provide useful species listings, frequency of occurrence and abundance data. We recommend multiple surveys from one site and day and night surveys for providing most complete species listings. Cluster analysis of reefs using Jaccard similarity indicies showed that reefs within a region clustered together and that reefs in close geographical proximity generally had the highest similarity. Data showed spatial distributions and species abundance patterns consistent with previous studie
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Evaluating the use of roving diver and transect surveys to assess the coral reef fish assemblage off southeastern Hispaniola
The relatively little-studied fish fauna off southeastern Hispaniola was rapidly assessed using a combination of visual survey techniques including transects and roving diver surveys. It was found that when combined, both methods provided a more complete overall species assessment than either method was able to provide in isolation. Being able to conduct rapid species assessments is becoming increasingly more important as a conservation tool. Data on species composition, sighting frequency, and abundance of all fishes were collected using both methods. Abundance was recorded in four logarithmic-based categories (roving diver method) while the number of fishes were counted within 40-m2 transects (transect method). Both methods were similar in recording the most abundant species, while a greater number of rare species (especially fishery-targeted species) were recorded with the roving diver method. The most abundant groupers were Cephalopholis cruentata and C. fulva. The most abundant parrotfishes were Scarus taeniopterus, Sparisoma aurofrenatum, and Scarus iserti. The most conspicuous differences between fishes off southeastern Hispaniola and elsewhere in the tropical western Atlantic were the low abundance and smaller size of harvested species such as groupers, snappers (Fam. Lutjanidae), and grunts (Fam. Haemulidae). With the roving diver method, more time could be spent surveying (instead of placing transect lines), resulting in a greater number of species being recorded. Additionally, well-trained volunteers can adopt the roving diver method as part of their regular diving program. Transect surveys were able to provide information such as length (biomass) and actual density measures that were not recorded in roving diver surveys. Thus, these methods were complementary and should be used in conjunction when conducting rapid assessments of fish assemblages, especially to detect the effects of overfishing
Surveying coral reef fishes : a manual for data collection, processing, and interpretation of fish survey information for the tropical Northwest Atlantic
In order to utilize the untapped resources of volunteers, REEF and TNC, in active partnership, established the REEF Fish Survey Project. The Project involves the training and mobilization of a large corps of volunteers and is currently the only program with the technical and organizational ability to gather marine biodiversity data in a systematic and reliable manner. Objectives of the project are: 1.) to provide training and education opportunities for SCUBA divers and snorkelers to learn to identify and appreciate marine life 2.) to make data and summary reports readily accessible to the marine science, resource management, and conservation communities 3.) to promote the diving community as conservation-minded and active partner in the long-term protection of coral reefs and other marine systems 4.) to encourage support and implementation of effective marine conservation strategies developed through government, private or public frameworkshttps://nsuworks.nova.edu/cnso_bio_facbooks/1003/thumbnail.jp
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The Role Of Small Islands In Marine Subsistence Strategies: Case Studies From The Caribbean
Caribbean archaeologists have tended to focus exclusively on the prehistory of the largest islands, perhaps because large islands are believed to provide the landmass necessary to support long-term population growth and cultural development. Yet, as research here and elsewhere, e.g., the Pacific, is showing, small islands provided access to resources and landscapes that were not always readily available on the larger islands. Small islands often have superior terrestrial and, especially, marine resources; isolated ritual spaces; and more easily defended locations; although they are susceptible to more rapid overexploitation. This paper examines in detail human needs with regard to island size, demonstrating that small islands were crucial in the development of pre-Columbian Caribbean societies. Four case studies are presented to illustrate that small islands often were preferred over large islands throughout the Caribbean archipelagoes. Finally, these studies show that the prehistoric exploitation and overexploitation of small islands can provide significant insights for establishing baselines that can be used for modern management and conservation efforts. © Springer Science+Business Media, LLC 2008