English   español  
Please use this identifier to cite or link to this item: http://hdl.handle.net/10261/132766
Share/Impact:
Statistics
logo share SHARE logo core CORE   Add this article to your Mendeley library MendeleyBASE

Visualizar otros formatos: MARC | Dublin Core | RDF | ORE | MODS | METS | DIDL | DATACITE
Exportar a otros formatos:

Title

Many vulnerable or a few resilient specimens? Finding the optimal for reintroduction/restocking programs

AuthorsGil, María del Mar; Palmer, Miquel ; Grau, Amàlia; Balle, Salvador
Issue Date22-Sep-2015
PublisherPublic Library of Science
CitationPLoS ONE 10(9): e0138501 (2015)
AbstractMost reintroduction and restocking programs consist of releasing captive-raised juveniles. The usefulness of these programs has been questioned, and therefore, quality control is advisable. However, evaluating restocking effectiveness is challenging because mortality estimation is required. Most methods for estimating mortality are based on tag recovery. In the case of fish, juveniles are tagged before release, and fishermen typically recover tags when fish are captured. The statistical models currently available for analyzing these data assume either constant mortality rates, fixed tag non-reporting rates, or both. Here, instead, we proposed a method that considers the mortality rate variability as a function of age/size of the released juveniles. Furthermore, the proposed method can disentangle natural from fishing mortality, analyzing the temporal distribution of the captures reported by fishermen from multiple release events. This method is demonstrated with a restocking program of a top-predator marine fish, the meagre (Argyrosomus regius), in the Balearic Islands. The estimated natural mortality just after release was very high for young fish (m = 0.126 day for fish 180 days old), but it was close to zero for large/old fish. These large/old fish were more resilient to wild conditions, although a long time was needed to achieve a relevant reduction in natural mortality. Conversely, these large/old fish were more vulnerable to fishing, creating a trade-off in survival. The release age that maximizes the number of survivors after, for example, one year at liberty was estimated to be 1,173 days. However, the production cost of relatively old fish is high, and only a few fish can be produced and released within a realistic budget. Therefore, in the case of the meagre, increasing the number of released fish will have no or scarce effects on restocking success. Conversely, it is advisable implement measures to reduce the high natural mortality of young juveniles and/or the length of time needed to improve fish resilience.
Publisher version (URL)http://dx.doi.org/10.1371/journal.pone.0138501
URIhttp://hdl.handle.net/10261/132766
DOI10.1371/journal.pone.0138501
Identifiersdoi: 10.1371/journal.pone.0138501
issn: 1932-6203
Appears in Collections:(IMEDEA) Artículos
Files in This Item:
File Description SizeFormat 
Gil-PLOS-ONE-2015-v10-e0138501.PDF1,08 MBAdobe PDFThumbnail
View/Open
Show full item record
Review this work
 

Related articles:


WARNING: Items in Digital.CSIC are protected by copyright, with all rights reserved, unless otherwise indicated.