Interactions between longline vessels and seabirds in Kerguelen waters and a method to reduce seabird mortality

Published source details Cherel Y., Weimerskirch H. & Duhamel G. (1996) Interactions between longline vessels and seabirds in Kerguelen waters and a method to reduce seabird mortality. Biological Conservation, 75, 63-70.
Share Tweet Email

Actions

This study is summarised as evidence for the following.

	Action	Category
	Reduce seabird bycatch by releasing offal overboard when setting longlines Action Link
	Turn deck lights off during night-time setting of longlines to reduce bycatch Action Link
	Set longlines at night to reduce seabird bycatch Action Link

Reduce seabird bycatch by releasing offal overboard when setting longlines

A replicated and controlled study in the South Atlantic in February 1994 (Cherel et al. 1996) found that piping offal overboard whilst setting longlines greatly reduced the number of birds caught on 69 line sets, from 33 birds to three, equivalent to a decrease from 0.49 to 0.01 birds/1000 hooks. Caught birds were white-chinned petrels Procellaria aequinoctialis, and two grey-headed albatross Thalassarche chrysostoma (formerly Diomedea chrysostoma). There was a corresponding significant decrease in the rate of bird attacks on the bait for all species except wandering albatross D. exulans (92% decrease for black-browed albatross T. melanophris (formerly D. melanophris), 96% for grey-headed albatross and 96% for white-chinned petrel). Vessels were fishing for Patagonian toothfish Dissostichus eleginoides around South Georgia and Kerguelen Islands.
Turn deck lights off during night-time setting of longlines to reduce bycatch

A replicated and controlled study (Cherel et al. 1996) in February 1994 in the South Atlantic Patagonian toothfish Dissostichus eleginoides fishery found that seabird bycatch rates on longlines set at night were much lower for lines set when the decklights were turned off, compared to sets with the lights on (0.15 vs. 0.59 birds/1,000 hooks). A total of 21 white-chinned petrels Procellaria aequinoctialis were caught. This study is also discussed in ‘Set longlines at night to reduce seabird bycatch’.
Set longlines at night to reduce seabird bycatch

A replicated and controlled study (Cherel et al. 1996) in the Patagonian toothfish Dissostichus eleginoides fishery in the South Atlantic found that 38 birds (two grey-headed albatross Thalassarche chrysostoma, formerly Diomedea chrysostoma, and 36 white-chinned petrels Procellaria aequinoctialis) caught on 72 longlines (174,000 hooks) set in February 1994, were caught at a much higher rate on lines set at night, than during the day (1.00 vs. 0.38 birds/1,000 hooks). The study took place around South Georgia (UK) and Kerguelen Islands (France) (sectors 332 and 333). This study is also discussed in ‘Turn decklights off during night-time setting of longlines to reduce bycatch’.