Population dynamics and stock assessment of the spider prawn, Nematopalaemon tenuipes Henderson along the Maharashtra coast

Nematopalaemon tenuipes is an important component of non-penaeid prawn resources of the northwest coast of India. During 1979-82 period, it contributed 29.9% to the non-penaeid prawn and 5.6% to the total fish landings of Maharashtra. The von Bertalanffy growth parameter L∞, K and t(sub)0 were 77.38 mm, 1.31 and -0.02 year for the males while for the females these parameters were respectively 87.23 mm, 1.30 and -0.01 year. The natural mortality coefficient (M) was 3.54 and 3.52 and the average total mortality coefficient (Z) during the period was 9.09 and 7.79 for the males and females respectively. With the exploitation rates of 0.61 and 0.55 for the males and females during the period, the total stock of the species was 26,270 tonnes and the standing stock was 3,418 tonnes. The maximum sustainable yield (MSY) of the species under the prevailing fishing conditions was 15,744 tonnes which is close to the average yield of 14,726 tonnes from the nets. Hence further increase in effort is not suggested.

A review of spider majid crabs of the northern Arabian Sea, with particular reference to Pakistani species, and with description of an undescribed Pleistacantha

The present report deals with the history of work done on northern Arabian Sea majids, their zoogeographical consideration and recognition of present status of certain genera which are established by recent workers. I have nothing of substance to add to previous treatment by Griffin & Tranter (1986). Emphasis is given to species inhabiting coastal waters of Pakistan. The occurrence of the genus Pleistacantha in the Arabian Sea and its adjacent gulfs is discussed in detail due to presence of a unique female which was taken by Fridtj of Nansen Cruise in 1977. This seems to be an undescribed species. At the moment the female is just given as Pleistacantha sp1 till more specimens obtained determine its position. Some interesting features of Doclea muricata are also considered.

Watershed monitoring and the TMDL modeling to assess bacterial loading in estuarine environments to improve management

Shellfish bed closures along the North Carolina coast have increased over the years seemingly concurrent with increases in population (Mallin 2000). More and faster flowing storm water has come to mean more bacteria, and fecal indicator bacterial (FIB) standards for shellfish harvesting are often exceeded when no source of contamination is readily apparent (Kator and Rhodes, 1994). Could management reduce bacterial loads if the source of the bacteria where known? Several potentially useful methods for differentiating human versus animal pollution sources have emerged including Ribotyping and Multiple Antibiotic Resistance (MAR) (US EPA, 2005). Total Maximum Daily Load (TMDL) studies on bacterial sources have been conducted for streams in NC mountain and Piedmont areas (U.S. EPA, 1991 and 2005) and are likely to be mandated for coastal waters. TMDL analysis estimates allowable pollutant loads and allocates them to known sources so management actions may be taken to restore water to its intended uses (U.S. EPA, 1991 and 2005). This project sought first to quantify and compare fecal contamination levels for three different types of land use on the coast, and second, to apply MAR and ribotyping techniques and assess their effectiveness for indentifying bacterial sources. Third, results from these studies would be applied to one watershed to develop a case study coastal TMDL. All three watershed study areas are within Carteret County, North Carolina. Jumping Run Creek and Pettiford Creek are within the White Oak River Basin management unit whereas the South River falls within the Neuse River Basin. Jumping Run Creek watershed encompasses approximately 320 ha. Its watershed was a dense, coastal pocosin on sandy, relic dune ridges, but current land uses are primarily medium density residential. Pettiford Creek is in the Croatan National Forest, is 1133 ha. and is basically undeveloped. The third study area is on Open Grounds Farm in the South River watershed. Half of the 630 ha. watershed is under cultivation with most under active water control (flashboard risers). The remaining portion is forested silviculture.(PDF contains 4 pages)

Skimmers: Their Development and Use in Coastal Louisiana

The origin, development, and utilization of the skimmer net is reviewed along with other historical shrimp gears used in coastal Louisiana. The skimmer was developed to catch white shrimp, Penaeus setiferus, observed jumping over the cork line (headrope) of trawls being worked in shallow waters. A description of the gear is presented including basic components and various frame designs used by fishermen during its development. The advantages of skimmers over bottom trawls include: multiple use as both trawl and butterfly net (wing net), ease of deployment, increased maneuverability, reduction and greater survivability of bycatch, and ability to cover more area due to increased speed and continuous fishing capability. Disadvantages may include compromising vessel stability when stored upright on the deck, possible damage to water bottoms when improperly rigged, and limitation to a 12-foot (3.6 m) maximum depth due to size restrictions. The growing popularity of the skimmer net is evident by its introduction into North Carolina and inquiries from other southeastern Atlantic and Gulf coast states.

Acute toxicity of chlorpyrifos, cadusafos and diazinon to three Indian major carps (Catla catla, Labeo rohita and Cirrhinus mrigala) fingerlings

Fingerlings of three Indian major carps, viz. Catla catla (Hamilton-Buchanon), Labeo rohita (Hamilton-Buchanon) and Cirrhinus mrigala (Hamilton-Buchanon), were exposed to different concentrations of chlorpyrifos (lorsban 10 G), cadusafos (rugby 10 G) and diazinon (basudin 10 G) for a period of 96h with a view to determine the median lethal concentrations (LC sub50) values for each of chemicals. Of the tested concentrations, chlorpyrifos at a dose of 6.65 ppm, cadusafos at 2.0 ppm and diazinon at a dose of 8.40 ppm or above induced 100% mortalities within 96h of exposure. The 96h LC sub50 values of chlorpyrefos, cadusafos and diazinon were 1.66, 0.72 and 2.10 ppm for C. catla, 2.35, 0.72 and 2.97 for L. rohita and 2.35, 0.72 and 2.10 ppm for C. mrigala, respectively. Pesticide induced behavioral abnormalities observed in the present study included erratic movements, rapid operculum activities, jumping of fish out of the test media, violent spasm and convulsion.