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The behavior of inshore squid (Dorytheuthis pealeii) in response to a Nordmore-style finfish bycatch reduction grid was evaluated n Nantucket Sound off Cape Cod Massachusetts. Squid avoided the grid and escape by jetting and changing directions. Only 6.4% of the squid became stuck on the grid and 83.9% of these were able to eventually pass between the grid and its spacing into the codend. Squid approaching the grid from the top with their mantel oriented toward the grid were more likely to be caught.

A flexible sorting grid was tested in the US west coast groundfish trawl fishery for its ability to reduce the bycatch of rockfish, sablefish and Pacific halibut without reducing catches of targeted flatfish. The grid works by allowing fish smaller than it to enter the codend, while fish larger than the grid openings are able to escape. The flexible sorting grid used four-seam tube of netting 80 meshes deep and 100 meshes in circumference. It was inserted between the intermediate section of the bottom trawl and codend. Two vertical panels were used to direct fish towards an upward ramp.

A flexible sorting grid designed by industry was tested in the US west coast groundfish trawl fishery for its ability to reduce bycatch. The flexible sorting grid was made within a four-seam tube of netting, 50 meshes deep and 88 meshes in circumference. The grid was inserted between the intermediate section of the bottom trawl and the codend. A horizontal sorting panel crowds fish and directs them through an escape opening in the bottom of the trawl. A recapture net was used to quantify retention and escapement.

A mechanical separating bycatch reduction device was tested in the Spencer Gulf king prawn trawl fishery to reduce the incidental capture of giant cuttlefish (Sepia apama) and blue swimmer crabs (Portunus armatus). Different sizes of Nordmore grids were tested. Two Nordmore grids were inserted into the posterior extension sections and triangular escape exits were cut out. One grid was located in the extension with an angle of -45 degrees (small grid) and the second large grid was set at a 30 degree angle in the extension.

A review of recently published articles dealing with the effects of magnetic fields on elasmobranchs and potential use in bycatch avoidance was conducted. The authors suggest these papers ignore that teleosts may also demonstrate magnetite based magnetoreception and that electroreception is present in many teleosts. Based on this, the possibility of induction based indirect magenetoreception in telosts should also be considered. The authors suggest that experiments showing teleosts are insensitive to magnetic deterrents is likely a result of flawed design and sample sizes.

A laboratory study was conducted to determine the impact of an electrical field on mortality rates and histological changes on model marine organisms. The tests were carried out to provide more information on the impact of electrotrawling om marine species. Two species of invertebrates, brown shrimp (Crangon crangon L.0) and king ragworm (Alita virens S.) were used as model species for crustaceans and polycheates, respectively.

Alternative trap designs were tested to determine their ability to reduce bycatch of ecologically important herbivore species such as parrotfish and surgeonfish. Catches from traditional Antillean chevron traps were compared to catches from traps with 1) short escape gaps (20X2.5 cm), 2) traps with tall escape gaps (40X2.5 cm) and 3) traps with a panel of large aperture mesh. The mean number of fish caught in the various traps were: 11.84 (control), 4.88 (short gap trap), 4.43 (tall gap traps) and 0.34 (large mesh traps).

Experiments were conducted aboard longline vessels operating in the Seychelles targeting swordfish and tuna. Experimental longlines fitted with hook timers and temperature depth recorders were used to identify differences in species composition, quantity and depth of catch between night sets using a shallow basket (swordfish target) and day sets using both shallow and deep baskets (tuna target). The majority of species were caught during day sets (75%). Lancetfish was the main bycatch species during daytime sets.

Integrated weight longlines (IW) were tested for their ability to reduce sea bird bycatch in demersal longline fisheries. The target fishery for testing was the Pacific cod fishery operating in the Bering Sea, Alaska, USA. Three experimental mitigation techniques were tested: 1) IW line alone, 2) IW paired with streamer lines (IWPS) and 3) unweighted longlines with paired streamer (UWPS) against a control (UW). Information on catch rates, seabird abundance and attack rate, and gear sink rate and performance were collected.

Interactions between vertical lines under increased tension with a physical model of a North Atlantic right whale flipper was investigated. This was an updated experiment. The original flipper model was based on data (flipper outlines and bone measurements) collected from three different whales. The physical flipper was computer generated from these data and covered with 1/2 in neoprene rubber, which was overlayed with 1/8 in thick vinyl rubber sheeting. The flipper was made from fiberglass, was free flooding and covered with 1/2 in neoprene and then with 1/8 in vinyl-rubber.

This study investigated whether North Atlantic right whale behavior changes, in terms of response distance, to changing visual characteristics of rope mimics in their path. 20 ft rope mimics were made from two 10 ft sections of rigid PVC pipe, with an approximate diameter of 1 inch. The rope mimics were weighted and attached to a lobster buoy to simulate a vertical line in the water column. A 30.5 cm disk was placed around the rope for reference use in video footage. The following color ropes were used: black, green, two types of white (white and glow in the dark), orange and red.

Low-powered sound sources were tested for their ability to deter gray whales from potentially harmful areas. An acoustic device (1-s frequency modulated 1-3 kHz warble deterrent signal) was moored to the seafloor in the gray whales migration path off central Oregon. Observers (land based) tracked whales with a theodolite to locate whales as they passed the headland. Tracklines were compared between times when the acoustic deterrent was on and off.

A desk-based study was conducted to evaluate 'conservation-relevant elements' of local governments involved in coastal and aquatic resource management, particularly bycatch mitigation. Four sites were looked at: 1) Trat, Thailand, 2) Mahakam River, Indonesia, 3) Malampaya Sound Philippines and 4) Guimaras and Iloilo Straits, Philippines. The species of interest was Irrawaddy dolphin (Orcaella brevirostris) caught in small-scale fisheries.

Two models of high field strength neodymium magnets (N35-Ni and N35-NdFeB types) were tested to determine their ability to deter sharks incidentally captured in Spanish and  Portuguese longline fisheries operating in the Northeast Atlantic Ocean. The main shark species tested was blue shark (Prionace glauca). The larger magnet was 26 mm X 11 mm X 12 mm, 0.885 T and the smaller magnet was 20 mm X 13 mm X 15 mm, 0.464 t. Field test results indicated the magnets do not reduce blue shark catch rates and may instead have an attractive effect.

This article describes the design and fabrication of a prototype rope-less fishing system that might be used in the Gulf of Maine lobster fishery. Rope-less fishing gear, which secures vertical fishing lines to the bottom until they are released for hauling, is a potential mitigation measure to reduce vertical line entanglements of marine mammals including North Atlantic right whales, along with leatherback sea turtles. The prototypes consists of a flotation line spool capable of holding up to 900 m of 1/2 in line.

Acoustic deterrents were tested for their ability to deter humpback whales (Megaptera novaeangliae) from potential sources of entanglement. Low frequency (3 kHz, 135 +/- 5 db, 5 s emission interval and 400 ms emission duration) alarms were tested. Alarms were placed in the center of the northerly migration path (southern hemisphere) of humpback whales. Observers, who were unaware of the alarm status (i.e. on/off) tracked the pods as they passed the alarms. Sixty percent of the pods (N=137) passed within the assumed detectable range (500 m) of the alarm.

This study investigated the impact of rope polymer type, breaking strength and diameter in relation to the injury severity of entangled baleen whales, primarily North Atlantic Right whales (Eubalaena glacialis). Fishing gear removed from live and dead entangled whales from the US East Coast and Canadian Maritimes region between 1994 and 2010 were included in this study. Average tested breaking strength of removed rope was 2,616 bs, 26% below strength at manufacture. Median rope diameter was 3/8 in.

The ability of acoustic alarms to alert migrating humpback whales (Megaptera novaeangliae) to fishing gear was tested. Two alarms were used, each with a distinct tone. One alarm had a 5 kHz tone (5 s emission interval and 400 ms emission duration), and one had a 2-2.1 kHz swept tone (8 s emission interval and 1.5 s emission duration). The response of the whales in terms of changes to surface behavior and travel direction were investigated. A total of 108 migration tracks were collected using a theodolite. The study was conducted at Cape Solander, Sydney, Australia.

Documented entanglements, long-term population studies and mark-recapture studies were evaluated to determine the impact of cryptic mortality on North Atlantic right whales. Results suggest entangled adults had low initial survival (0.749). Adults that did survive the first year had survival rates similar (0.952) to those animals never entangled (0.961 female and 0.986 male). Juveniles had post entanglement survival rates similar to initial survival rates of entangled adults, 0.733, but lower than un-impacted juveniles (0.978).

Bryde's whale (Balaenoptera edeni) behavior was studied using suction-cup attached tags. Behavior was studied to identify potential mitigation measures that could reduce lethal vessel strikes in the Hauraki Gulf, New Zealand. Tagged whales spent 91% of their time at depths within the maximum draft of vessels. This behavior could increase the potential for vessel strikes. Analysis of vessel transits and whale sightings suggested that re-routing of vessel traffic in the Gulf would not be beneficial because whales are distributed throughout the Gulf.