| Autor: |
Bouyoucos, I. A., Simpfendorfer, C. A., Schwieterman, G. D., Eustache, K. B., Thiault, Lauric, Planes, S., Rummer, J. L. |
| Zdroj: |
Marine & Freshwater Research; 2024, Vol. 75 Issue 14, p1-12, 12p |
| Abstrakt: |
Context: Coastal habitats function as shark nursery areas; however, coastal habitats can experience extreme variation in abiotic conditions and are susceptible to human disturbances. Aims: Drivers of abundance were tested within a shark nursery-area system in two populations of reef-associated neonate sharks, namely, blacktip reef sharks (Carcharhinus melanopterus) and sicklefin lemon sharks (Negaprion acutidens). Methods: Catch data from a fisheries-independent gill-net survey (n = 90 sets from October 2018 to March 2019) at 10 sites around Moorea, French Polynesia, were used to test for associations between shark abundance and abiotic conditions (temperature, oxygen, pH, salinity, lunar phase and depth). Historical levels of fin-fish fishing effort, trampling (i.e. human movement through habitat), and coastal artificialisation (i.e. walls and embankments) estimated for each site were used to test for anthropogenic effects on shark abundance. Key results: There were no effects of any abiotic or anthropogenic factor on abundance of either species. Conclusions: Previous work corroborates our findings by demonstrating neonate sharks' physiological tolerance to extreme abiotic conditions and high survival in response to anthropogenic stressors. Alternatively, populations are already degraded from decades of coastal development. Implications: These data can aid in predicting the use of coastal habitats as shark nursery areas. Coastal waters can be crucial nursery grounds for young sharks, but these areas are subject to a wide range of environmental changes and human interference. Our study found no significant effects on newborn populations of two reef shark species. This indicates either their remarkable resilience to environmental shifts and human presence in their habitats, or that these populations are historically degraded. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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