A pilot study to determine the movements of buoy line used in the crab pot fishery to assess bottlenose dolphin entanglement

A pilot study on the characteristics of crab pot buoy line movements to assess bottlenose dolphin entanglement was conducted from 19 September to 30 September 2005 in the Charleston Harbor, Charleston, South Carolina. The objectives of this study were to determine: 1) the movements of the buoy line in the water at various tidal stages, current strengths, lengths of line, and water depth, 2) if lead-core rope was a better alternative to nylon rope, 3) and if the manner of deployment of the gear affected the suspension of the line in the water and on the bottom. Diamond braided nylon (#10) rope of varying length (20 ft. – 80 ft.) were used during 31 trials and stiffened (polypropylene lead-core) rope was used in four trials. Observations of the buoy line movements were captured with an Atlantis underwater camera attached to a Digital DPC-1000 video recorder. Results from this study showed that: 1) the method used for deployment was important in keeping the buoy line from arcing or coiling, 2) little to no arcing occurred in water current velocities of >0.20 m/s, 3) rope lengths of ≥50 ft. deployed in <10 ft. of water produced waving in the water column and arcing on the bottom, 4) slack tide was a period of increased risk of entanglement for bottlenose dolphins, and 5) poly lead-core rope was not a good alternative to nylon rope unless in deep water with strong water current velocities. This pilot study produced questions that can be used for future studies on the characteristics of buoy line movements in the crab pot fishery as it relates to bottlenose dolphin entanglements.

Assessment of contaminant body burdens and histopathology of fish and shellfish species frequently used for subsistence food by Alaskan Native communities

Subsistence food items can be a health concern in rural Alaska because community members often rely on fish and wildlife resources not routinely monitored for persistent bioaccumulative contaminants and pathogens. Subsistence activities are a large part of the traditional culture, as well as a means of providing protein in the diets for Tribal members. In response to the growing concerns among Native communities, contaminant body burden and histopathological condition of chum and sockeye salmon (Oncorhynchus keta and Oncorhynchus nerka) and the shellfish cockles and softshell clams (Clinocardium nuttallii and Mya arenaria) were assessed. In the Spring of 2010, the fish and shellfish were collected from traditional subsistence harvest areas in the vicinity of Nanwalek, Port Graham, and Seldovia, AK, and were analyzed for trace metals and residues of organic contaminants routinely monitored by the NOAA National Status & Trends Program (NS&T). Additionally, the fish and shellfish were histologically characterized for the presence, prevalence and severity of tissue pathology, disease, and parasite infection. The fish and shellfish sampled showed low tissue contamination, and pathologic effects of the parasites and diseases were absent or minimal. Taken together, the results showed that the fish and shellfish were healthy and pose no safety concern for consumption. This study provides reliable chemistry and histopathology information for local resource managers and Alaska Native people regarding subsistence fish and shellfish use and management needs.

Atlas of the shallow-water benthic habitats of American Samoa, Guam, and the Commonwealth of the Northern Mariana Islands

The National Oceanic and Atmospheric Administration (NOAA) National Ocean Service (NOS) initiated a coral reef research program in 1999 to map, assess, inventory, and monitor U.S. coral reef ecosystems (Monaco et al. 2001). These activities were implemented in response to requirements outlined in the Mapping Implementation Plan developed by the Mapping and Information Synthesis Working Group (MISWG) of the Coral Reef Task Force (CRTF) (MISWG 1999). As part of the MISWG of the CRTF, NOS' Biogeography Branch has been charged with the development and implementation of a plan to produce comprehensive digital coral-reef ecosystem maps for all U.S. States, Territories, and Commonwealths within five to seven years. Joint activities between Federal agencies are particularly important to map, research, monitor, manage, and restore coral reef ecosystems. In response to the Executive Order 13089 and the Coral Reef Conservation Act of 2000, NOS is conducting research to digitally map biotic resources and coordinate a long-term monitoring program that can detect and predict change in U.S. coral reefs, and their associated habitats and biological communities. Most U.S. coral reef resources have not been digitally mapped at a scale or resolution sufficient for assessment, monitoring, and/or research to support resource management. Thus, a large portion of NOS' coral reef research activities has focused on mapping of U.S. coral reef ecosystems. The map products will provide the fundamental spatial organizing framework to implement and integrate research programs and provide the capability to effectively communicate information and results to coral reef ecosystem managers. Although the NOS coral program is relatively young, it has had tremendous success in advancing towards the goal to protect, conserve, and enhance the health of U.S. coral reef ecosystems. One objective of the program was to create benthic habitat maps to support coral reef research to enable development of products that support management needs and questions. Therefore this product was developed in collaboration with many U.S. Pacific Territory partners. An initial step in producing benthic habitat maps was the development of a habitat classification scheme. The purpose of this document is to outline the benthic habitat classification scheme and protocols used to map American Samoa, Guam and the Commonwealth of the Northern Mariana Islands. Thirty-two distinct benthic habitat types (i.e., four major and 14 detailed geomorphological structure classes; eight major and 18 detailed biological cover types) within eleven zones were mapped directly into a geographic information system (GIS) using visual interpretation of orthorectified IKONOS satellite imagery. Benthic features were mapped that covered an area of 263 square kilometers. In all, 281 square kilometers of unconsolidated sediment, 122 square kilometers of submerged vegetation, and 82.3 square kilometers of coral reef and colonized hardbottom were mapped.

Efficiency of bycatch reduction devices in small otter trawls used in the Florida shrimp fishery

Two bycatch reduction devices (BRDs)—the extended mesh funnel (EMF) and the Florida fisheye (FFE)—were evaluated in otter trawls with net mouth circumferences of 14 m, 17 m, and 20 m and total net areas of 45 m2. Each test net was towed 20 times in parallel with a control net that had the same dimensions and configuration but no BRD. Both BRDs were tested at night during fall 1996 and winter 1997 in Tampa Bay, Florida. Usually, the bycatch was composed principally of finfish (44 species were captured); horseshoe crabs and blue crabs seasonally predominated in some trawls. Ten finfish species composed 92% of the total finfish catch; commercially or recreationally valuable species accounted for 7% of the catch. Mean finfish size in the BRD-equipped nets was usually slightly smaller than that in the control nets. Compared with the corresponding control nets, both biomass and number of finfish were almost always less in the BRD-equipped nets but neither shrimp number nor biomass were significantly reduced. The differences in proportions of both shrimp and finfish catch between the BRD-equipped and control nets varied between seasons and among net sizes, and differences in finfish catch were specific for each BRD type and season. In winter, shrimp catch was highest and size range of shrimp was greater than in fall. Season-specific differences in shrimp catch among the BRD types occurred only in the 14-m, EMF nets. Finfish bycatch species composition was also highly seasonal; each species was captured mainly during only one season. However, regardless of the finfish composition, the shrimp catch was relatively constant. In part as a result of this study, the State of Florida now requires the use of BRDs in state waters.

Towing resistance of ottar [i.e. otter] trawls used for shrimps from small mechanised boats

Attempts have been made to determine the towing resistance of the shrimp otter trawls operated from small trawlers off Cochin and the actual resistance on the warps for eight different boats working under the normal fishing conditions have been measured. Engine Horse Power utilised for towing the gear at normal speed and fishing conditions has also been estimated.

Factors influencing colour production from the sugar medium used for the rapid approximation of bacterial counts in fishery products

Results of the studies carried out to elucidate the factors influencing colour production from the sugar medium used for the rapid approximation of bacterial counts in fishery products are reported. The effect of particle size, trace elements, salt soluble protein and non-protein fractions, rate of multiplication of bacteria, in the medium, surface bacteria and the rate of colour production by individual strains of bacteria were studied. It is observed that the best results are obtained when a sea-water homogenate is used.

Comparative fishing experiments with two trawl designs used in the inshore waters off Kakinada (Andhra Pradesh)

The importance of small trawlers for the economic exploitation of the inshore demersal fisheries is well recognized and accordingly mechanized boats of sizes 30' and 32' fitted with engines of h.p. ranging from 30 to 45 came into existence particularly at Kakinada. The need to work out the most suitable trawling gear for these classes of boats becomes imperative and as an appurtenance to this, comparative fishing experiments were attempted with different trawls. In the present communication certain observations made on the relative catch efficiency of two different trawl nets used in combination with two different shaped otter boards are given.