Saved in:
| Main Author: | |
|---|---|
| Format: | Artículo científico |
| Language: | en |
| Published: |
Universidad Autónoma de Baja California
2015
|
| Subjects: | |
| Online Access: | https://www.redalyc.org/articulo.oa?id=48036868004 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
Table of Contents:
- Resilience of Sphyrna lewini, Rhizoprionodon longurio, and Carcharhinus falciformis at the entrance to the Gulf of California after three decades of exploitation Emmanuel Furlong-Estrada Javier Tovar-Ávila Juan Carlos Pérez-Jiménez Eduardo Ríos-Jara Ciencias de la Tierra Resilience Resilience elasm obranchs elasm obranchs rebound potential Given their biological characteristics, sharks exhibit low res ilience and thereby are consider ed a fishery resource particularly vulnerable to overfishi ng. Yet, for several decades, three shark species (Sphyrna lewini, Rhizoprionodon longurio, and Carcharhinus falciformis) have contributed consistently to the catches of the artisanal shark fishery at the entrance to the Gulf of California, showing a certain degree of resilience. The aim of this study was to estimate the ir capacity to recover from disturbances, based on their reboun d potential (r2M ), and analyze the factors that may be favoring their capacity to recover from fishing pressure in the region. Catch records, siz e composition of landings reported in previous st udies and from undertaken surve ys, as well as publis hed information on life history parameters were used in the present analysis. Rhizoprionodon longurio showed high productivity (r2M=0.083) and thus high resilience, whereas C. falciformis and S. lewini presented medium productivities (r2M= 0.053 and 0.062, respectivel y), but alternative scenarios to consider uncertainty in the life history parameters of C. falciformis and S. lewini placed them in the low productiv ity category. All species pres ented low productivity when the more conservative natura l mortality (e.g., 1.25 M ) to achieve maximum sustainable yield was considered. Catches were dominated by juveniles of S. lewini , and by preadults and adults of R. longurio and C. falciformis during all the analyzed period; this and their consistent cont ribution to landings suggest apparent populat ion stability. Such stabili ty might be related to their biological producti vity, elasticit y, wide distribution range, migratory habits, and size segregation. Nonetheless, changes that occurred in this fisher y over the last three decades may have also played an important role in the c atch levels, particularly in the case of C. falciformis. Quantitative population assessments of these species to determine the optimum levels of extraction in the region are urgently needed. 2015 artículo científico 0185-3880 https://www.redalyc.org/articulo.oa?id=48036868004 en http://www.redalyc.org/revista.oa?id=480 Ciencias Marinas application/pdf Universidad Autónoma de Baja California Ciencias Marinas (México) Num.1 Vol.41