Mitigating bycatch of threatened seabirds: the effectiveness of branch line weighting in pelagic longline fisheries

2018 ◽  
Vol 22 (4) ◽  
pp. 376-385 ◽  
Author(s):  
S. Jiménez ◽  
A. Domingo ◽  
R. Forselledo ◽  
B. J. Sullivan ◽  
O. Yates
Keyword(s):  
Branch Line ◽  
Longline Fisheries ◽  
Pelagic Longline ◽  
Threatened Seabirds

Seabird bycatch vulnerability in pelagic longline fisheries based on modelling of a long-term dataset

2021 ◽  
pp. 1-16
Author(s):  
CAN ZHOU ◽  
NIGEL BROTHERS
Keyword(s):  
Capture Event ◽  
Retrieval Rate ◽  
Competitive Environments ◽  
Global Concern ◽  
Competitive Species ◽  
Spatio Temporal ◽  
Longline Fisheries ◽  
Pelagic Longline

Summary The incidental mortality of seabirds in fisheries remains a serious global concern. Obtaining unbiased and accurate estimates of bycatch rates is a priority for seabird bycatch mitigation and demographic research. For measuring the capture risk of seabird interactions in fisheries, the rate of carcass retrieval from hauled gear is commonly used. However, reliability can be limited by a lack of direct capture observations and the substantial pre-haul bycatch losses known to occur, meaning incidence of seabird bycatch is underestimated. To solve this problem, a new measure (bycatch vulnerability) that links an observed interaction directly to the underlying capture event is proposed to represent the capture risk of fishery interactions by seabirds. The new measure is not affected by subsequent bycatch loss. To illustrate how to estimate and analyse bycatch vulnerability, a case study based on a long-term dataset of seabird interactions and capture confirmation is provided. Bayesian modelling and hypothesis testing were conducted to identify important bycatch risk factors. Competition was found to play a central role in determining seabird bycatch vulnerability. More competitive environments were riskier for seabirds, and larger and thus more competitive species were more at risk than smaller sized and less competitive species. Species foraging behaviour also played a role. On the other hand, no additional effect of physical oceanic condition and spatio-temporal factors on bycatch vulnerability was detected. Bycatch vulnerability is recommended as a replacement for the commonly used bycatch rate or carcass retrieval rate to measure the capture risk of an interaction. Combined with a normalized contact rate, bycatch vulnerability offers an unbiased estimate of seabird bycatch rate in pelagic longline fisheries.

The effect of light attractor color in pelagic longline fisheries

2021 ◽  
Vol 235 ◽  
pp. 105822
Author(s):  
André S. Afonso ◽  
Bruno Mourato ◽  
Humberto Hazin ◽  
Fábio H.V. Hazin
Keyword(s):  
Longline Fisheries ◽  
Pelagic Longline ◽  
Effect Of Light

Comparison of the effectiveness of paired and single tori lines for preventing bait attacks by seabirds and their bycatch in pelagic longline fisheries

2013 ◽  
Vol 140 ◽  
pp. 14-19 ◽  
Author(s):  
Noriyosi Sato ◽  
Hiroshi Minami ◽  
Nobuhiro Katsumata ◽  
Daisuke Ochi ◽  
Kotaro Yokawa
Keyword(s):  
Longline Fisheries ◽  
Pelagic Longline

scholarly journals Toothed whale and shark depredation indicators: A case study from the Reunion Island and Seychelles pelagic longline fisheries

PLoS ONE ◽  
2018 ◽  
Vol 13 (8) ◽  
pp. e0202037 ◽  
Author(s):  
Njaratiana Rabearisoa ◽  
Philippe S. Sabarros ◽  
Evgeny V. Romanov ◽  
Vincent Lucas ◽  
Pascal Bach
Keyword(s):  
Reunion Island ◽  
Toothed Whale ◽  
Réunion Island ◽  
Longline Fisheries ◽  
Pelagic Longline
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