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Large pelagic sharks are caught incidentally in the swordfish and tuna fisheries of the Mediterranean Sea. In our study, twelve shark species were documented as bycatch over three years from 1998 to 2000. Blue shark (Prionace glauca) was the predominant species in all gears and areas examined. Shortfin mako (Isurus oxyrinchus), common thresher shark (Alopias vulpinus), and tope shark (Galeorhinus galeus) were the next most abundant shark species found in more than half of the areas sampled. Catch composition varied both in the areas and gears investigated.

A study was conducted from 1998 to 2001 on blue shark (Prionace glauca) by-catch of the Italian and Greek surface drifting swordfish long-line fisheries in the Mediterranean Sea. The focus was on examining whether catches are related to some environmental, spatial, temporal or operational parameters and to what extent, applying generalized linear model (GLM) approaches. Spatial and temporal factors were the most influential regarding blue shark distribution and abundance, with a considerable interaction between them; the modeled environmental factors were of minor importance.

Blue sharks (Prionace glauca) and oilfish (Ruvettus pretiosus) are frequently caught incidentally in the swordfish surface drifting longline fishery of the eastern Mediterranean Sea. An information theoretic generalized additive model approach, modelling separately: (1) the probability of making a catch; and (2) the positive catch rates, suggested the presence of intra-annual variations in their abundance and revealed interesting associations with some environmental features. Blue sharks were more frequently encountered during late summer in cool water masses.

A ten year study in the Aegean Sea, divided into two sub-periods (1995-2000; 2003-2006) examined bottom trawl fishery data for chondrichthyan fishes. A total of 30 different species were caught making up 14.3% of the total catch in weight and 2.2% by number. A significant decrease in the chondrichthan species richness  and abundance was observed. More than 90% (by number) of individuals were discarded at sea. 

This Handbook aims to:detail the design, operation and use of hoppers (back deck water tanks/sorting devices) in trawl fisheries across Australia;enable the sharing of industry knowledge on hoppers amongst fishers from all Australian trawl fisheries;provide readily accessible information to fishers on the use and application of hoppers;>facilitate the broader adoption among trawl fisheries of best practice use of hoppers.

Three modified hoop-net designs were tested in the Gasconade and Osage Rivers of Missouri to determine their ability to reduce turtle bycatch without reducing the capture of targeted catfish.  The three designs included an excluder net with tightly spread mesh and a sewn in ring, a chimney-set design and a loose-weave design.  The chimney-net design was the only one that significantly reduced turtle bycatch (84%), while not decreasing the number of average size of flathead catfish.

Wisconsin-type fyke nets were modified in an effort to reduce the incidental bycatch of turtles, without significantly reducing the catch of targeted fish species.  The tests were conducted in three rivers (Missouri, Mississippi and Gasconade) in Missouri.  The net was modified by adding four lines in the vertical gap of the net and this modification was successful at significantly reducing turtle bycatch with no significant decrease in the quantity of fish caught.