9 resultados para Leaders
em Aquatic Commons
Resumo:
Sea level rise and inundation were stated to be the highest priorities in the community-developed Ocean Research Priorities Plan and Implementation Strategy in 2005. Although they remain stated priorities, very few resources have been allocated towards this challenge. Inundation poses a substantial risk to many coastal communities, and the risk is projected to increase because of continued development, changes in the frequency and intensity of inundation events, and acceleration in the rate of sea-level rise along our vulnerable shorelines. (PDF contains 4 pages) There is an increasing urgency for federal and state governments to focus on the local and regional levels and consistently provide the information, tools, and methods necessary for adaptation. Calls for action at all levels acknowledge that a viable response must engage federal, state and local expertise, perspectives, and resources in a coordinated and collaborative effort. A workshop held in December 2000 on coastal inundation and sea level rise proposes a shared framework that can help guide where investments should be made to enable states and local governments to assess impacts and initiate adaptation strategies over the next decade.
Resumo:
Executive Summary: Baseline characterization of resources is an essential part of marine protected area (MPA) management and is critical to inform adaptive management. Gray’s Reef National Marine Sanctuary (GRNMS) currently lacks adequate characterization of several key resources as identified in the 2006 Final Management Plan. The objectives of this characterization were to fulfill this need by characterizing the bottom fish, benthic features, marine debris, and the relationships among them for the different bottom types within the sanctuary: ledges, sparse live bottom, rippled sand, and flat sand. Particular attention was given to characterizing the different ledge types, their fish communities, and the marine debris associated with them given the importance of this bottom type to the sanctuary. The characterization has been divided into four sections. Section 1 provides a brief overview of the project, its relevance to sanctuary needs, methods of site selection, and general field procedures. Section 2 provides the survey methods, results, discussion, and recommendations for monitoring specific to the benthic characterization. Section 3 describes the characterization of marine debris. Section 4 is specific to the characterization of bottom fish. Field surveys were conducted during August 2004, May 2005, and August 2005. A total of 179 surveys were completed over ledge bottom (n=92), sparse live bottom (n=51), flat sand (n=20), and rippled sand (n=16). There were three components to each field survey: fish counting, benthic assessment, and quantification of marine debris. All components occurred within a 25 x 4 m belt transect. Two divers performed the transect at each survey site. One diver was responsible for identification of fish species, size, and abundance using a visual survey. The second diver was responsible for characterization of benthic features using five randomly placed 1 m2 quadrats, measuring ledge height and other benthic structures, and quantifying marine debris within the entire transect. GRNMS is composed of four main bottom types: flat sand, rippled sand, sparsely colonized live bottom, and densely colonized live bottom (ledges). Independent evaluation of the thematic accuracy of the GRNMS benthic map produced by Kendall et al. (2005) revealed high overall accuracy (93%). Most discrepancies between map and diver classification occurred during August 2004 and likely can be attributed to several factors, including actual map or diver errors, and changes in the bottom type due to physical forces. The four bottom types have distinct physical and biological characteristics. Flat and rippled sand bottom types were composed primarily of sand substrate and secondarily shell rubble. Flat sand and rippled sand bottom types were characterized by low percent cover (0-2%) of benthic organisms at all sites. Although the sand bottom types were largely devoid of epifauna, numerous burrows indicate the presence of infaunal organisms. Sparse live bottom and ledges were colonized by macroalgae and numerous invertebrates, including coral, gorgonians, sponges, and “other” benthic species (such as tunicates, anemones, and bryozoans). Ledges and sparse live bottom were similar in terms of diversity (H’) given the level of classification used here. However, percent cover of benthic species, with the exception of gorgonians, was significantly greater on ledge than on sparse live bottom. Percent biotic cover at sparse live bottom ranged from 0.7-26.3%, but was greater than 10% at only 7 out of 51 sites. Colonization on sparse live bottom is likely inhibited by shifting sands, as most sites were covered in a layer of sediment up to several centimeters thick. On ledge bottom type, percent cover ranged from 0.42-100%, with the highest percent cover at ledges in the central and south-central region of GRNMS. Biotic cover on ledges is influenced by local ledge characteristics. Cluster analysis of ledge dimensions (total height, undercut height, undercut width) resulted in three main categories of ledges, which were classified as short, medium, and tall. Median total percent cover was 97.6%, 75.1%, and 17.7% on tall, medium, and short ledges, respectively. Total percent cover and cover of macroalgae, sponges, and other organisms was significantly lower on short ledges compared to medium and tall ledges, but did not vary significantly between medium and tall ledges. Like sparse live bottom, short ledges may be susceptible to burial by sand, however the results indicate that ledge height may only be important to a certain threshold. There are likely other factors not considered here that also influence spatial distribution and community structure (e.g., small scale complexity, ocean currents, differential settlement patterns, and biological interactions). GRNMS is a popular site for recreational fishing and boating, and there has been increased concern about the accumulation of debris in the sanctuary and potential effects on sanctuary resources. Understanding the types, abundance, and distribution of debris is essential to improving debris removal and education efforts. Approximately two-thirds of all observed debris items found during the field surveys were fishing gear, and about half of the fishing related debris was monofilament fishing line. Other fishing related debris included leaders and spear gun parts, and non-gear debris included cans, bottles, and rope. The spatial distribution of debris was concentrated in the center of the sanctuary and was most frequently associated with ledges rather than at other bottom types. Several factors may contribute to this observation. Ledges are often targeted by fishermen due to the association of recreationally important fish species with this bottom type. In addition, ledges are structurally complex and are often densely colonized by biota, providing numerous places for debris to become stuck or entangled. Analysis of observed boat locations indicated that higher boat activity, which is an indication of fishing, occurs in the center of the sanctuary. On ledges, the presence and abundance of debris was significantly related to observed boat density and physiographic features including ledge height, ledge area, and percent cover. While it is likely that most fishing related debris originates from boats inside the sanctuary, preliminary investigation of ocean current data indicate that currents may influence the distribution and local retention of more mobile items. Fish communities at GRNMS are closely linked to benthic habitats. A list of species encountered, probability of occurrence, abundance, and biomass by habitat is provided. Species richness, diversity, composition, abundance, and biomass of fish all showed striking differences depending on bottom type with ledges showing the highest values of nearly all metrics. Species membership was distinctly separated by bottom type as well, although very short, sparsely colonized ledges often had a similar community composition to that of sparse live bottom. Analysis of fish communities at ledges alone indicated that species richness and total abundance of fish were positively related to total percent cover of sessile invertebrates and ledge height. Either ledge attribute was sufficient to result in high abundance or species richness of fish. Fish diversity (H`) was negatively correlated with undercut height due to schools of fish species that utilize ledge undercuts such as Pareques species. Concurrent analysis of ledge types and fish communities indicated that there are five distinct combinations of ledge type and species assemblage. These include, 1) short ledges with little or no undercut that lacked many of the undercut associated species except Urophycis earlii ; 2) tall, heavily colonized, deeply undercut ledges typically with Archosargus probatocephalus, Mycteroperca sp., and Pareques sp.; 3) tall, heavily colonized but less undercut with high occurrence of Lagodon rhomboides and Balistes capriscus; 4) short, heavily colonized ledges typically with Centropristis ocyurus, Halichoeres caudalis, and Stenotomus sp.; and 5) tall, heavily colonized, less undercut typically with Archosargus probatocephalus, Caranx crysos and Seriola sp.. Higher levels of boating activity and presumably fishing pressure did not appear to influence species composition or abundance at the community level although individual species appeared affected. These results indicate that merely knowing the basic characteristics of a ledge such as total height, undercut width, and percent cover of sessile invertebrates would allow good prediction of not only species richness and abundance of fish but also which particular fish species assemblages are likely to occur there. Comparisons with prior studies indicate some major changes in the fish community at GRNMS over the last two decades although the causes of the changes are unknown. Species of interest to recreational fishermen including Centropristis striata, Mycteroperca microlepis, and Mycteroperca phenax were examined in relation to bottom features, areas of assumed high versus low fishing pressure, and spatial dispersion. Both Mycteroperca species were found more frequently when undercut height of ledges was taller. They often were found together in small mixed species groups at ledges in the north central and southwest central regions of the sanctuary. Both had lower mode size and proportion of fish above the fishery size limit in heavily fished areas of the sanctuary (i.e. high boat density) despite the presence of better habitat in that region. Black sea bass, C. striata, occurred at 98% of the ledges surveyed and appeared to be evenly distributed throughout the sanctuary. Abundance was best explained by a positive relationship with percent cover of sessile biota but was also negatively related to presence of either Mycteroperca species. This may be due to predation by the Mycteroperca species or avoidance of sites where they are present by C. striata. Suggestions for monitoring bottom features, marine debris, and bottom fish at GRNMS are provided at the end of each chapter. The present assessment has established quantitative baseline characteristics of many of the key resources and use issues at GRNMS. The methods can be used as a model for future assessments to track the trajectory of GRNMS resources. Belt transects are ideally suited to providing efficient and quantitative assessment of bottom features, debris, and fish at GRNMS. The limited visibility, sensitivity of sessile biota, and linear nature of ledge habitats greatly diminish the utility of other sampling techniques. Ledges should receive the bulk of future characterization effort due to their importance to the sanctuary and high variability in physical structure, benthic composition, and fish assemblages. (PDF contains 107 pages.)
Resumo:
The Zanzibar Workshop Proceedings consists of the report and the Statement of the Workshop and provides a rich understanding of the dynamics of traditional, indigenous, small-scale and artisanal fisheries and fishing communities in the Eastern and Southern African (ESA) context. The issues covered include: the saga of rights denied to coastal lands, fishing, and threats to livelihood arising from lack of recognition of traditional rights and the livelihood needs of people in the region; the aspirations of coastal and inland communities to maintain or improve their livelihoods; and a bottom-up perspective on access rights to fishing, post-harvest rights and economic and social rights. This report will be a valuable source of information for community organizers, trade union leaders, government officials and the donor community, including multilateral organizations, researchers and for all those who are interested in the well-being of ESA fishing communities.
Resumo:
Offshore pound net leaders in the southern portion of Chesapeake Bay in Virginia waters were documented to incidentally take protected loggerhead, Caretta caretta, and Kemp’s ridley, Lepidochelys kempii, sea turtles. Because of these losses, NOAA’s National Marine Fisheries Service (NMFS) in 2004 closed the area to offshore pound net leaders annually from 6 May to 15 July and initiated a study of an experimental leader design that replaced the top two-thirds of the traditional mesh panel leader with vertical ropes (0.95 cm) spaced 61 cm apart. This experimental leader was tested on four pound net sites on the eastern shore of Chesapeake Bay in 2004 and 2005. During the 2 trial periods, 21 loggerhead and Kemp’s ridley sea turtles were found interacting with the control leader and 1 leatherback turtle, Dermochelys coriacea, was found interacting with the experimental leader. Results of a negative binomial regression analysis comparing the two leader designs found the experimental leader significantly reduced sea turtle interactions (p=0.03). Finfish were sampled from the pound nets in the study to assess finfish catch performance differences between the two leader designs. Although the conclusions from this element of the experiment are not robust, paired t-test and Wilcoxon signed rank test results determined no significant harvest weight difference between the two leaders. Kolmogorov-Smirnov tests did not reveal any substantive size selectivity differences between the two leaders.
Resumo:
Gray’s Reef National Marine Sanctuary (GRNMS) is located 32.4 km offshore of Sapelo Island, Georgia. The ecological importance of this area is related to the transition between tropical and temperate waters, and the existence of a topographically complex system of ledges. Due to its central location, GRNMS can be used as a focal site to study the accumulation and impacts of marine debris on the Atlantic continental shelf offshore of the Southeast United States. Previously, researchers characterized marine debris in GRNMS and reported that incidence of the debris at the limited densely colonized ledge sites was significantly greater than at sand or sparsely colonized live bottom, and is further influenced by the level of boating activity and physiographic characteristics (e.g., ledge height). Information gleaned from the initial marine debris characterization was used to devise a strategy for prioritizing cleanup and monitoring efforts. However, a significant gap in knowledge was the rate of debris accumulation. The primary objective of this study was to select, mark, and perform initial marine debris surveys at permanent monitoring sites within GRNMS to quantify long-term trends in types, abundance, impacts, and accumulation rates of debris. Ledge sites were selected to compare types, abundance, and accumulation rates of marine debris between a) areas of high and low use and b) short and tall ledges. Nine permanent monitoring sites were marked and initially surveyed in 2007/2008. Surveys were conducted within a 50 x 4 m transect for a total survey area of 200 square meters. All debris was removed and detailed information was taken on the types of debris, quantity, and associations with benthic fauna. Information on associations with benthic fauna included degree of entanglement, type of organism with which it is entangled or resting on, degree of fouling, and visible impacts such as tissue abrasions. Sites were re-surveyed approximately one year later to quantify new accumulation. During the initial survey, a total of ten debris items, totaling 16.3 kg in weight, were removed from two monitoring stations, both “tall” sites within the area of high boat use. Year-one accumulation totaled five items and approximately 7 kg in weight. Similar to the initial survey, all debris was found at sites in the area of high boat use. However, in contrast to the initial survey, two of these items were found on medium-height ledges. Removed items included fishing line, leaders, rope, plastic, and fabric. Although items were often encrusted in benthic biota or entangled on the ledge, impacts such as abrasions or other injuries were not observed. During the 2009 monitoring efforts, volunteer divers were trained to conduct the survey. Monitoring protocols were documented for GRNMS staff and included as an appendix of this report to enable long-term monitoring of sites. Additionally, national reconnaissance data (e.g. satellite, radar, aerial surveys) and other information on known fishing locations were examined for patterns of resource use and correlations with debris occurrence patterns. A previous model predicting the density of marine debris based on ledge features and boat use was refined and the results were used to generate a map of predicted debris density for all ledges.
Resumo:
Where natural resources are a key component of the rural economy, the ability of the poor to realize their visions for the future depends significantly on institutional structures that govern resource access and management. This case study reports on an initiative on the shores of Lake Kariba in Zambia, where lakeshore residents face competition over fishing, tourism, and commercial aquaculture. Multistakeholder dialogue produced agreements with investors and increased accountability of state agencies and traditional leaders, enabling communities to have greater influence over their futures through improvements in aquatic resource governance. The report documents the rationale for the approach followed and steps in the capacity-building process, discusses obstacles encountered, and identifies lessons for policymakers and practitioners seeking to implement a similar approach.
Resumo:
There is growing recognition that the performance of the fisheries sector depends on the communities responsible for activities within it. These communities include fishers, processors, fish mongers, traders, local leaders, fishery administrators etc. On the basis of this, characterisation and diagnostic studies were conducted in 1995 focussing on mainly the fishers and opinion leaders on the major and some minor water bodies in Uganda. The study revealed that the desire to earn income is the driving force behind the malfishing practices experienced on Uganda fisheries. The destructive fishing gears and fishing methods as responses advanced by the fishers and opinion leaders were seines and cast nets on lakes Victoria, Kyoga and Albert and to a less extent traps
Resumo:
The fisheries of Lake Albert have come under increasing focus due to several driving forces that have synergistically evolved resulting into concerns from diverse stakeholders. The driving forces include: the commercialization of the fisheries with entry into the value chain of industrial fish processing, a decline in fish stocks especially of the large-size fishes and the emergency of the light - fishing targeting small pelagic fishes. In addition, the assumption by some opinion leaders that light-fishing (use of light) has destroyed the Nile perch fishery of Lake Albert, other factors such as cross-border fishing conflicts, the emergence of oil, an influx of traders in fish-related activities, and the limited regulatory and enforcement regimes for the diverse commercially exploited fish fauna of Lake Albert all require continuous information and action.
Resumo:
A baseline survey for the project which had been conducted in 2009 had gaps that could not allow assessment of project performance in the outcome and impact indicators to be made. This study was, therefore, commissioned to reconstruct the baseline data, aligned to the impact and outcome indicators on the project logframe and results framework, against which project achievements could be assessed. The purpose and scope of the study was to reconstruct the baseline data and analysis describing the situation prior to QAFM Project inception, taking 2008 as the baseline year, which was aligned to the project logframe outcome and impact indicators; to collect data on current status to compare project outcome (and where possible impact) in improved fish handling sites in comparison with the baseline as well as with comparable non-improved fish landing sites as control group. The study was conducted through secondary data search from sources at NaFIRRI, DFR and ICEIDA. Field data collection was carried out using a sample survey covering 312 respondents including boat and gear owners, crew members, processors and traders at eight project and two control landing sites. Key Informant Interviews were conducted with DFOs and BMU leaders in the study districts and landing sites respectively.