Comparing autonomous underwater vehicle (AUV) and vessel-based tracking performance for locating acoustically tagged fish

Autonomous underwater vehicles (AUV’s) are increasingly used to collect physical, chemical, and biological information in the marine environment. Recent efforts include merging AUV technology with acoustic telemetry to provide information on the distribution and movements of marine fish. We compared surface vessel and AUV tracking capabilities under rigorous conditions in coastal waters near Juneau, Alaska. Tracking surveys were conducted with a REMUS 100 AUV equipped with an integrated acoustic receiver and hydrophone. The AUV was programmed to navigate along predetermined routes to detect both reference transmitters at 20–500 m depths and tagged fish and crabs in situ. Comparable boat surveys were also conducted. Transmitter depth had a major impact on tracking performance. The AUV was equally effective or better than the boat at detecting reference transmitters in shallow water, and significantly better for transmitters at deeper depths. Similar results were observed for tagged animals. Red king crab, Paralithodes camtschaticus, at moderate depths were recorded by both tracking methods, while only the AUV detected Sablefish, Anoplopoma fimbria, at depths exceeding 500 m. Strong currents and deep depths caused problems with AUV navigation, position estimation, and operational performance, but reflect problems encountered by other AUV applications that will likely diminish with future advances, enhanced methods, and increased use.

A survey of deep-water coral and sponge habitats along the west coast of the US using a remotely operated vehicle: NOAA Fisheries Survey Vessel (FSV)'Bell M. Shimada', November 1-5, 2010

Remotely operated vehicle (ROV) surveys were conducted from NOAA’s state-of-the-art Fisheries Survey Vessel (FSV) Bell M. Shimada during a six-day transit November 1-5, 2010 between San Diego, CA and Seattle, WA. The objective of this survey was to locate and characterize deep-sea coral and sponge ecosystems at several recommended sites in support of NOAA’s Coral Reef Conservation Program. Deep-sea corals and sponges were photographed and collected whenever possible using the Southwest Fisheries Science Center’s (SWFSC) Phantom ROV ‘Sebastes’ (Fig. 1). The surveyed sites were recommended by National Marine Sanctuary (NMS) scientists at Monterey Bay NMS, Gulf of the Farallones NMS, and Olympic Coast NMS (Fig. 2). The specific sites were: Sur Canyon, The Football, Coquille Bank, and Olympic Coast NMS. During each dive, the ROV collected digital still images, video, navigation, and along-track conductivity-temperature-depth (CTD), and optode data. Video and high-resolution photographs were used to quantify abundance of corals, sponges, and associated fishes and invertebrates to the lowest practicable taxonomic level, and also to classify the seabed by substrate type. A reference laser system was used to quantify area searched and estimate the density of benthic fauna.

Effects of blood extraction on horseshoe crabs (Limulus polyphemus)

Horseshoe crabs (Limulus polyphemus) are caught by commercial fishermen for use as bait in eel and whelk fisheries (Berkson and Shuster, 1999)—fisheries with an annual economic value of $13 to $17 million (Manion et al.1). Horse-shoe crabs are ecologically important, as well (Walls et al., 2002). Migratory shorebirds rely on horseshoe crab eggs for food as they journey from South American wintering grounds to Arctic breeding grounds (Clark, 1996). Horse-shoe crabs are also essential for public health (Berkson and Shuster, 1999). Biomedical companies bleed horse-shoe crabs to extract a chemical used to detect the presence of endotoxins pathogenic to humans in injectable and implantable medical devices (Novitsky, 1984; Mikkelsen, 1988). Bled horseshoe crabs are returned to the wild, subject to the possibility of postbleeding mortality. Recent concerns of overharvesting have led to conflicts among commercial fishermen, environmentalists acting on behalf of the shorebirds, and biomedical companies (Berkson and Shuster, 1999; Walls et al., 2002).

The physiological effects of multiple forced submergences in loggerhead sea turtles (Caretta caretta)

Sea turtles are subjected to involuntary submergence and potential mortality due to incidental capture by the commercial shrimp fishing industry. Despite implementation of turtle excluder devices (TEDs) to reduce at-sea mortality, dead stranded turtles continue to be found in near-record numbers along the coasts of the western Atlantic Ocean and northern Gulf of Mexico. Although this mortality may be due to an increase in the number of turtles available to strand, one alternative explanation is that sea turtles are repetitively submerged (as one fishing vessel follows the path of another) in legal TEDs. In the present study, laboratory and field investigations were undertaken to examine the physiological effects of multiple submergence of loggerhead sea turtles (Caretta caretta). Turtles in the laboratory study were confined during the submersion episodes, whereas under field conditions, turtles were released directly into TED-equipped commercial fishing nets. Under laboratory and field conditions, pre- and postsubmergence blood samples were collected from turtles submerged three times at 7.5 min per episode with an in-water rest interval of 10, 42, or 180 min between submergences. Analyses of pre- and postsubmergence blood samples revealed that the initial submergence produced a severe and pronounced metabolic and respiratory acidosis in all turtles. Successive submergences produced significant changes in blood pH, Pco2, and lactate, although the magnitude of the acid-base imbalance was substantially reduced as the number of submergences increased. In addition, increasing the interval between successive submergences permitted greater recovery of blood homeostasis. No turtles died during these studies. Taken together, these data suggest that repetitive sub-mergence of sea turtles in TEDs would not significantly affect their survival potential provided that the animal has an adequate rest interval at the surface between successive submergences.

Acute effect of sumithion on certain blood parameters and mortality rate of fish, Heteropneustes fossilis (Bloch)

The acute toxic effect of the toxicant sumithion (50% E.C.) on mortality rate (after 24, 48, 72, and 96 h), total RBC count and haemoglobin content (after 48 and 72 h) on Heteropneustes fossilis was investigated at four concentrations (9.7, 10.7 and 11.1 ppm). The sumithion treated fishes showed lower RBC and Hb levels than the untreated ones. A gradual decrease in the total RBC counts and Hb contents was recorded with increasing concentration of toxicant after 72 h but the blood showed fluctuating values after 48 h of treatment.

Toxic effects of dietary seaweeds Sargassum bovianum, Caulera faridii and Gracilaria corticata on blood parameters of albino rats

The present communication deals with the feeding trials of brown (Sargassum bovianum), green (Caulerpa faridii) and red (Gracilaria corticola) seaweeds in albino rats for a period of thirty days in order to investigate their digestibility and acceptability as supplementary food for animals. The parameters used were: changes in blood hemoglobin, ESR, MCHC, PCV and plasma vitamin levels. The result revealed that all the three species of seaweeds had acceptability up to 5% level, as no ill effect was noted during the experiment. But at 10% and 20% levels, marked changes were observed in blood parameters with diarrhea, vomiting and convulsions indicating possibilities of either tissue and muscular dystrophy, gastrointestinal tract necrosis or functional disorder of central nervous system. A heavy mortality was noted due to excessive water loss through diarrhea and vomiting. However, no mortality was observed after 22nd day at both 10% and 20% levels with subsided clinical signs. The results suggest that these three seaweed species could be used safely as a supplementary food, in native form, in animals at low concentrations.

Cell types in the peripheral blood of waking catfish Clarias batrachus (Lin.)

Different types of haematocytes found in the peripheral blood of walking catfish Clarias batrachus, have been characterized and identified using morphological, morphometric and cytochemical techniques. These cells are: erythrocytes, reticulocytes, large and small lymphocytes, thrombocytes, monocytes and polymorphonuclear leucocytes (neutrophils).

Sulfide binding characteristics of blood serum in Calyptogena pacifica and Vesicomya gigas

The sulfide binding characteristics of blood serum were studied in vitro in two deep-sea vesicomyid clams, Calyptogena pacifica and Vesicomya gigas. Both the C. pacifica and the V. gigas serum concentrated sulfide at least an order of magnitude above ambient levels. V. gigas accumulated sulfide faster than C. pacifica, reaching saturation at 5000 M after an hour. C. pacifica bound sulfide at half the rate of V. gigas, reaching saturation in about two hours at a substantially higher concentration of sulfide. The observed distribution of the animals near cold seeps in the Monterey Submarine Canyon can be explained by their different sulfide binding abilities. The hypothesis that cold seeps are actually much more unstable sources of sulfide than previously assumed is explored.

In vitro phagocytic study of blood leucocytes and peritoneal macrophages of walking catfish Clarias batrachus ( Ham.) against Aeromonas hydrophila and Escherichia coli.

In observation of in vitro phagocytic activity against Aeromonas hydrophila isolate 34k (a virulent form) and Escherichia coli (an avirulent bacteria) of neutrophil- and monocyte-like cells of walking catfish Clarias batrachus showed phagocytosis. N eutrophils and monocytes phagocytized the avirulent form of bacterial isolate more than the virulent one. Other blood leucocytes did not show phagocytosis. Peritoneal macrophage of the fish were separated by glycogen elicitation and the macrophages were being adhered on plastic cover slips for studying their in vitro phagocytic activity. Most of the cells were alive after adherence and showed phagocytosis against the virulent and avirulent bacteria. The percent phagocytosis and phagocytic index were higher against the avirulent E. coli than the virulent A. hydrophila.

Effect of long-term exposure to endosulfan on blood cell count in Channa gachua

In the present investigation, live specimens of Channa gachua were exposed to sublethal concentrations, i.e., 0.0017 and 0.00087 ppm of endosulfan for a period of 60 days. After the completion of 60 days, red and white blood corpuscles were counted from control as well as experimental fishes.

Studies on the ice storage characteristics of blood clam Anadara granosa meat

Ice-storage study of blood clam (Anadara granosa) meat in direct contact and out of contact (in 200 gauge polyethylene bag) with ice was taken up to assess the amenability of the meat to icing. Changes in moisture, total protein, non-protein nitrogen, α amino nitrogen, total volatile base nitrogen, glycogen, free fatty acid, peroxide value, total bacterial count and coliform count were followed every day. The raw and cooked meat were also subjected to organoleptic evaluation. The study showed that the clam meat can be ice-stored in very good condition out of contact with ice in polyethylene packets for 4 days and in direct contact with ice for 2 days.

Pickle from blood clam (Anadara granosa) meat

A pickle was prepared from blood clam (Anadara granosa) meat. The pickle was subjected to biochemical, bacteriological and organoleptic tests at different stages of storage. The pickle has a shelf-life of more than 5½ months at ambient temperature.

Merging effects of vitamin E and C on biological factors, blood characteristics and resistance against thermal stress in rainbow trout (Onchorhyncus mykiss)

This study was conducted to assay the effects of different levels of dietary vitamins C and E on growth indices and survival and resistance against thermal stress of rainbow trout (Oncorhynchus mykiss) in pond culture of Marzan abad from December 2011 to February 2011. Seven diets were supplemented. 300 fish with the average weight of 17 g were introduced to ponds for 60 days. The results showed that the highest and the lowest weight gain were in fish fed with diet containing 50 mg/kg vitamin C and E and 0 mg/kg vitamin C and E(control) , respectively. The highest and the lowest Feed Conversion Ratio (FCR) were measured in control and diet 50 mg/kg vitamin C and E. There is a significant difference in their treatments (P<0.05). Also, the lowest and highest amount of Weight Gain (WG) were observed in (E) treatment with 165.04% and 117.5% in control, the highest and lowest Specific Growth Rate (SGR), Protein Efficiency Ratio (PER), Condition Factor (CF) was found in control and treatment 50 mg/kg vitamin C and E, respectively(P<0.05). In conclusion vitamin C and E have an important role in enhancement of growth performance and feed efficiency of rainbow trout.The highest red blood cells were found in combined treatments and which the vitamin C was added.The highest RBC were found in E treatment(1.1×104 /mm3) and the lowest one in control (P˂0.05). Counting white blood cells also confirmed highest quantity in combined treatments with (69.83×104/mm3) and the lowest one (28.83×104 /mm3) in control. In conclusion these vitamins have a significant role in blood characteristics. Meantime, the resistance against termal stress was measured at the end of 60 days by facing fishes into 5 centigrade warmer water so consentration of Cortisol and Glucose measured for this reason.The lowest cortisol amount was measured in E treatment with 188.74 ng/ml and the highest was found in control(P<0.05). There was a significant difference in blood glucose consentration of fishes in F treatment with (78.66 mg/dl) and control with 136 mg/dl as a highest one(P<0.05).