Sea Turtles

Displaying 21 - 30 of 44

Species: 

Dermochelys coriacea

The worldwide decline in leatherback turtles has been caused, in part, by bycatch in fisheries. Leatherback turtles most often entangled or hooked externally in pelagic longline fisheries (Garrison 2003), but are capable of swimming to the surface to breathe (Witzell and Cramer 1995).  Although not all incidental captures lead to mortality, the number of leatherbacks caught each year is very high and post release mortality rates are unknown. Lewison et al (2004) estimated that the global longlining fleets took 50 to 60,000 leatherbacks in 2000. 

Distribution: 

Circumglobal in tropical to sub-polar waters

Population: 

Decreasing
Photo: Mass DMF, taken under NOAA 50 CFR 222.310 with authorization of the ESA

IUCN Status: 

Critically Endangered

Type: 

Reptile

Bycatch Threat: 

Longlines, gillnets, trawls, pot/traps

Species: 

Caretta caretta

The main cause of the decline of loggerhead turtles, and the current primary threat to global populations is bycatch in longlines, gillnets, trawls, traps and pots, and dredges. Loggerhead can be hooked in the mouth or another part of their body when trying to consume bait, entangled in gillnets or ropes, or caught in a trawl or dredge. Longlines, gillnets, and trawls are responsible for the majority of sea turtle bycatch events around the world (Wallace et al, 2010). Commercial longlines incidentally caught an estimated 200,000 loggerhead turtles in 2000 (Lewison et al, 2004).

Distribution: 

Circumglobal, in tropical and subtropical waters

Population: 

Unknown
Photo: NOAA

IUCN Status: 

Globally Endangered

Type: 

Reptile

Bycatch Threat: 

Longlines, gillnets, trawls, traps and pots, and dredges

Study Type: 

Field study in the wild

Location: 

Australia

Target catch: 

Bigeye tuna

Effect on bycatch species: 

None reported

Effect on target catch: 

Weighted longlines had a slightly higher overall CPUE (1.3 fish/100 hooks) compared to traditional longlines (1.08 fish/100 hooks) and caught more bigeye (0.95 fish/ 100 hooks) than traditional longlines (0.56 fish/100 hooks). Catch rates were not very

Article: 

Bycatch species: 

Reduction technique: 

Fishing Gear: 

Study Type: 

Field study in the wild

Location: 

Northern Australia

Target catch: 

Prawns

Effect on bycatch species: 

JT 2 design did not prevent capture of sea turtles

Effect on target catch: 

Caught 5.2% more tiger prawns and 6.9% more endeavour prawns than standard net

Article: 

Bycatch species: 

Reduction technique: 

Fishing Gear: 

Study Type: 

Field study in the wild

Location: 

Northern Australia

Target catch: 

Prawns

Effect on bycatch species: 

JT 1 design did not prevent capture of sea turtles

Effect on target catch: 

Caught 6.6% more tiger prawns and 10.5% more endeavour prawns than standard net

Article: 

Bycatch species: 

Reduction technique: 

Fishing Gear: 

Study Type: 

Field study in the wild

Location: 

Chesapeake Bay, Virginia

Target catch: 

Finfish, including: Atlantic tread herring (Opisthonema oglinum), harvestfish (Peprilus alepidotus), butterfish (Peprilus triacanthus), Atlantic croaker (Micropogonias undulatus) and weakfish (Cynoscion regalis)

Effect on bycatch species: 

Significant reduction of sea turtles bycatch

Effect on target catch: 

No difference for four species, increased catch of a fifth

Article: 

Bycatch species: 

Reduction technique: 

Fishing Gear: 

Study Type: 

Field study in the wild

Location: 

Northern Australia

Target catch: 

Prawns

Effect on bycatch species: 

Downward facing TEDs reduced sea turtle catches by 100%

Effect on target catch: 

Reduced the proportion of soft and damaged prawns by 63.2% and reduced catches of tiger prawns by 6.3%

Article: 

Bycatch species: 

Reduction technique: 

Fishing Gear: 

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