Physiological stress in the smalltooth sawfish: effects of ontogeny, capture method, and habitat quality

Endangered species research

Gregg R. Poulakis^3¹  Bianca K. Prohaska^1²  Ryan Knotek^4³  Dana M. Bethea^2⁴  Rachel M. Scharer^3⁵ 

[1] Fish and Wildlife Research Institute, Florida Fish and Wildlife Conservation Commission, Charlotte Harbor Field Laboratory, Port Charlotte, Florida 33954, USA^3;Florida State University Coastal and Marine Laboratory, St. Teresa, Florida 32358, USA^1;NOAA National Marine Fisheries Service, Southeast Fisheries Science Center, Panama City, Florida 32408, USA^5;NOAA National Marine Fisheries Service, Southeast Regional Office, Protected Resources Division, St. Petersburg, Florida 33710, USA^2;University of Massachusetts Boston, School for the Environment, Boston, Massachusetts 02125, USA^4

关键词: Pristis pectinata;    Stress physiology;    Metabolic stress;    Chronic stress;    Anthropogenic effects;    Nursery;    Habitat loss;    Blood chemistry;   

DOI  :  10.3354/esr00892

学科分类：动物科学

来源: Inter-Research

【 摘 要 】

Similar to other elasmobranchs, the smalltooth sawfish Pristis pectinata is slow growing, matures late in life, and produces relatively few young, all factors that have contributed to its sensitivity to dramatic population declines from overfishing and habitat loss. Currently, the physiological stress response of these fish to capture or to other physiological challenges such as habitat loss, climatic changes, or pollution is unknown. In the absence of these data, conservation plans may be less effective, making populations susceptible to further declines. We examined basic stress physiology over ontogeny and as a function of capture using different fishing gears. We also examined stress parameters to test whether degraded habitat and water quality from altered habitats may have resulted in chronic stress in juveniles. Results suggested that the stress response to capture by all methods was low, particularly for blood lactate, compared to other elasmobranchs examined to date. Metabolic stress was found to change over ontogeny, with young of the year (YOY) eliciting the highest responses. Glucose, pCO2, bicarbonate, potassium, and hematocrit indicated that gillnet capture induced greater stress responses than longline capture. Significantly higher metabolic stress was observed in YOY and juveniles captured in the 2 nurseries most influenced by anthropogenic activities, the Peace and Caloosahatchee rivers, than in the 2 relatively pristine nurseries in Everglades National Park. Overall, the low physiological stress responses to all capture methods investigated in this study suggest that this species is resilient, which should promote optimism for recovery of the population.

【 授权许可】

Unknown