The potential consequences of climate variability and change on coastal areas and marine resources: report of the Coastal Areas and Marine Resources Sector Team, U.S. National Assessment of the Potential Consequences of Climate Variability and Change, U.S. Global Change Research Program

Coastal and marine ecosystems support diverse and important fisheries throughout the nation’s waters, hold vast storehouses of biological diversity, and provide unparalleled recreational opportunities. Some 53% of the total U.S. population live on the 17% of land in the coastal zone, and these areas become more crowded every year. Demands on coastal and marine resources are rapidly increasing, and as coastal areas become more developed, the vulnerability of human settlements to hurricanes, storm surges, and flooding events also increases. Coastal and marine environments are intrinsically linked to climate in many ways. The ocean is an important distributor of the planet’s heat, and this distribution could be strongly influenced by changes in global climate over the 21st century. Sea-level rise is projected to accelerate during the 21st century, with dramatic impacts in low-lying regions where subsidence and erosion problems already exist. Many other impacts of climate change on the oceans are difficult to project, such as the effects on ocean temperatures and precipitation patterns, although the potential consequences of various changes can be assessed to a degree. In other instances, research is demonstrating that global changes may already be significantly impacting marine ecosystems, such as the impact of increasing nitrogen on coastal waters and the direct effect of increasing carbon dioxide on coral reefs. Coastal erosion is already a widespread problem in much of the country and has significant impacts on undeveloped shorelines as well as on coastal development and infrastructure. Along the Pacific Coast, cycles of beach and cliff erosion have been linked to El Niño events that elevate average sea levels over the short term and alter storm tracks that affect erosion and wave damage along the coastline. These impacts will be exacerbated by long-term sea-level rise. Atlantic and Gulf coastlines are especially vulnerable to long-term sea-level rise as well as any increase in the frequency of storm surges or hurricanes. Most erosion events here are the result of storms and extreme events, and the slope of these areas is so gentle that a small rise in sea level produces a large inland shift of the shoreline. When buildings, roads and seawalls block this natural migration, the beaches and shorelines erode, threatening property and infrastructure as well as coastal ecosystems.

An integrated biogeographic assessment of reef fish populations and fisheries in Dry Tortugas: Effects of No-take Reserves

The Tortugas Integrated Biogeographic Assessment presents a unique analysis of demographic changes in living resource populations, as well as societal and socioeconomic benefits that resulted from the Tortugas Ecological Reserves during the first five years after their implementation. In 2001, state and federal agencies established two no-take reserves within the region as part of the Florida Keys National Marine Sanctuary. The northern reserve (Tortugas Ecological Reserve North) was established adjacent to the Dry Tortugas National Park, which was first declared a national monument in 1935. The reserves were designed to protect a healthy coral reef ecosystem that supports diverse faunal assemblages and fisheries, serves as important spawning grounds for groupers and snappers, and includes essential feeding and breeding habitats for seabirds. The unique ecological qualities of the Tortugas region were recognized as far back as 1850, and it remains an important ecosystem and research area today. The two main goals of the Tortugas Ecological Reserve Integrated Ecological Assessment were: 1) to determine if demographic changes such as increases in abundance, average size and spawning potential of exploited populations occurred in the Tortugas region after reserve implementation; and 2) whether short-term economic losses occurred to fishers displaced by the reserve. This project utilized a biogeographic approach in which information on the physical features (i.e., habitat) and oceanographic patterns were first used to determine the spatial distribution of selected fish populations within and outside the Tortugas Ecological Reserve. Before-and-after reserve implementation comparisons of selected fish populations were then conducted to determine if demographic changes occurred in reef fish assemblages. These comparisons were done for the Tortugas region and also for a subset of available habitats within the Tortugas Ecological Reserve Study Area. Social and economic impacts of the reserves were determined through: 1) analyses of commercial landings and revenues from fishers, operating in the Tortugas region before and after reserve implementation and 2) surveys of recreational tour guides. Analyses of the commercial landings and revenues excluded areas inside Dry Tortugas National Park because commercial fishing has been prohibited within park boundaries since 1992. Key findings and outcomes of this integrated ecological assessment are organized by chapter and listed below.

1987 ecosystem view of management research in the Myakka River: review of Phase I and Phase II reports

This memorandum has four parts. The first is a review and partial synthesis of Phase 1 and Phase 2 Reports by Dr. Ernest Estevez of the Mote Marine Laboratory to the Board of County Commissioners of Sarasota County, Florida. The review and synthesis emphasizes identification of the most important aspects of the structure of the Myakka system in terms of forcing functions, biological components, and major energy flows. In this context, the dominant primary producers, dominant fish species and food habits, and major environmental variables were of articular interest. A major focus of the review and synthesis was on the river zonations provided in the report and based on salinity and various biological indicators. The second part of this memorandum is a review of a draft report by Mote Marine Laboratory on evaluation of potential water quality impacts on the Myakka River from proposed activities in the watershed. This Memorandum's third part is a review of resource-management related ecosystem models in the context of possible future models of the Myakka River Ecosystem. The final part of this memorandum is proposed future work as an extension of the initial reports.

On continued culture trials of Lates calcarifer (Bloch) and Oreochromis mossambicus in the ponds of Kharland Research Station, Panvel, Maharashtra

Pond culture trials of Lates calcarifer (Bloch) were initiated in the ponds of Kharland Research Station, Panvel, from 1985 up to 1989 by adopting varying methods of inputs of commonly available organic substances comprising de-oiled cake of groundnut, rice bran and raw cattle dung. Although provision of zooplankton generated under phased fertilisation technique resulted in considerable yield level, subsequent trials in combination with direct feed methods gave higher yield. Trials during 1990-91 adopting similar feed input techniques were continued but by stocking the seed of both Lates and Oreochromis mossambicus with yield percentage around 72.23 for Lates and 27.73 for Oreochromis. Trials were further continued during next three years. In relation to the organic input levels the yields rate for seven months period was in the range of 119.4 kg/ha to 250.4 kg/ha for Lates. In case of Oreochromis the yield rate varied between 28.5 to 153.32 kg/ha indicating the influence of differential stocking rates and size of the seed of two species.

Final report of the targeted research on Indian mackerel and sharks and national plan of action for conservation and management of shark resources, Thailand

Research included: population structure of Indian mackerel (Rastrelliger kanagurta); a National Plan of Action for the conservation and management of sharks; levels of heavy metals in shark products; and a database on rays.

Hard days and nights: hardships at work, a lack of support at home, and little or no social security combine to create a bleak future for women fishsellers in Mangalore, India

Mangalore is a port city situated in the west coast state of Karnataka in India. The city hosts both large-scale and small-scale fisheries along its coastline. Traditionally, fishermen catch the product and sell it at a daily auction in the harbour to women vendors, who thereafter transport the goods to the market for commercial sale. The trade starts early in the morning, when the fishermen return to the harbour from their nightly fishing.

Stock enhancement in Japan and Taiwan

Stock enhancement has been recognized as one of the essential strategies that can sustain and increase the resources of coastal fisheries. It has been practiced for over a century, with more than 100 species released to date in worldwide programs. Among the countries in Asia, Japan and Taiwan have already established the practice of stock enhancement. Details are given of the main species, number or seedstock produced and released in 1996 in Japan. The species released by the Taiwan Fisheries Research Institute 1976-1995 are also described.