Effects of the SMART™ (Selective Magnetic and Repellent-Treated) hook on spiny dogfish catch in a longline experiment in the Gulf of Maine

Bull shark ( Carcharhinus leucas ) exclusion properties of the sharksafe barrier and behavioral validation using the ARIS technology

“…For example, grade C8 barium-ferrite permanent magnets generate an approximate surface magnetic flux of 3850 G, where the geomagnetic flux ranges from 0.25 to 0.65 G. Being several orders of magnitude greater in strength, the novel stimulus produced by the permanent magnets is hypothesized to overstimulate the ampullary system and deter approaching elasmobranchs. To date, numerous studies tested this hypothesis and have produced mixed findings (Stoner and Kaimmer, 2008;Rigg et al, 2009;Robbins et al, 2011;O'Connell et al, 2010O'Connell et al, , 2011aO'Connell et al, , 2012bO'Connell et al, , 2013a. Stoner and Kaimmer (2008) examined the behavior of Pacific halibut (Hippoglossus stenolepis), a teleost, and spiny dogfish (Squalus acanthias), an elasmobranch, in response to neodymium-iron-boride magnets (Nd 2 Fe 14 B).…”

Spatiotemporal overlap of spiny dogfish (Squalus acanthias) and commercial fisheries in the northeast U.S. shelf large marine ecosystem

“…During autumn, availability to the OT fishery increased with mature female abundance. The plausibility of this result is supported by recent field studies that examined devices or repellents aimed at deterring spiny dogfish from multiple gears, including trawls, in the NES LME (Chosid et al, 2012;O'Connell et al, 2012). For the SGN fishery, an opposite trend of reduced availability was observed when there was a higher abundance of mature female spiny dogfish during spring.…”

“…The use of commercial statistics in tracking abundance trends is often discouraged because of nonrandom fishery behavior, particularly because fishing crews search for concentrations of fish rather than fish at random (Paloheimo and Dickie, 1964;Salthaug and Aanes, 2003); however, fishery-dependent data have provided a rare opportunity to examine fishery behavior and investigate how fisheries are distributed with respect to a marine resource. Clustering of spiny dogfish CPUE in the SGN fishery indicated that this fishery, compared with the OT fishery, targeted spiny dogfish more directly.…”

“…Rather, we examined whether increased spatial overlap between spiny dogfish and commercial fisheries has manifested as increases in local abundance on fishing grounds-a hypothesis that has motivated a number of studies where bycatch reduction of spiny dogfish has been examined (Tallack and Mandelman, 2009;Chosid et al, 2012;O'Connell et al, 2012). The objectives of this study were 1) to describe the behavior of major commercial fisheries that catch spiny dogfish (either directly or indirectly as bycatch) between 1989 and 2009, 2) to quantify spatial overlap and investigate spatiotemporal interactions between spiny dogfish distribution (derived from the NEFSC bottom trawl survey) and commercial fisheries (i.e., effort and catch) during this time period, and 3) to explore and relate changes in availability of spiny dogfish to catchability on commercial fishing grounds.…”

Hooks equipped with magnets can increase catches of blue shark (Prionace glauca) by longline fishery

“…This is the first paper describing the magnetic effect on blue shark catches in real fishing conditions. Previous papers concerning the blue shark analyzed only the electropositive effects (Godin Cosandey et al, 2013;O'Connell et al, 2014d) (Appendix A). In our case, the blue shark probably detects the presence of bait on the longlines at long distance.…”