Survival rates and physiological recovery responses in the lesser-spotted catshark (Scyliorhinus canicula) after bottom-trawling.
Comp Biochem Physiol A Mol Integr Physiol
; 233: 1-9, 2019 07.
Article
en En
| MEDLINE
| ID: mdl-30905654
ABSTRACT
In 2019, Europe will adopt a no-discards policy in fisheries. This entails the landing of captured species unless strong evidence is provided supporting their survival and recovery after fishing. Thus, research on this topic is gaining momentum. Bottom-trawling, as a non-selective fishing method, is characterized by a high proportion of discards including vulnerable key species, such as demersal sharks. Their survival may also depend on capture depth. By paralleling onboard and laboratory experiments with the small-spotted catshark, Scyliorhinus canicula, we offer a robust experimental design to assess the survival of discarded sharks. Catsharks were captured by bottom-trawling at two depths (shallow ~89â¯m and deep ~479â¯m). Blood samples were collected following trawl capture and analyzed for stress biomarkers (lactate, osmolality, phosphate, urea). During recovery in onboard tanks, behavior was video-recorded and fish were re-sampled after 24â¯h. A second experiment was conducted in laboratory facilities to simulate air-exposure after trawling and to analyze the physiological recovery. Our results showed that 95.7% of the animals survived 24â¯h after trawling. We confirmed that trawling elicited acute stress responses in catshark but that they managed to recover. This was demonstrated by lactate concentrations that were 2.6â¯mM upon capture, but recovered to assumed baselines after 24â¯h (0.2â¯mM). Non-invasive video monitoring revealed behavioral differences with depth, whereby those captured at 89â¯m depth required longer to recover than those captured at 479â¯m depth. Implementation of standardized survival studies by fishery managers can benefit from holistic physiological approaches, such as the one proposed here.
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Texto completo:
1
Bases de datos:
MEDLINE
Asunto principal:
Tiburones
/
Explotaciones Pesqueras
Límite:
Animals
/
Humans
Idioma:
En
Revista:
Comp Biochem Physiol A Mol Integr Physiol
Asunto de la revista:
BIOLOGIA MOLECULAR
/
FISIOLOGIA
Año:
2019
Tipo del documento:
Article
País de afiliación:
España