Title
Trends in sympatric otariid populations suggest resource limitations in the Peruvian Humboldt Current System
Date Issued
01 July 2021
Access level
open access
Resource Type
journal article
Publisher(s)
Elsevier
Abstract
Sympatric species evolve mechanisms to avoid competition and coexist. In the Humboldt Current System (HCS), populations of South American sea lions (SASL, Otaria byronia) and South American fur seals (SAFS, Arctocephalus australis) fluctuate mostly due to ENSO events and prey availability. We evaluate population trajectories of Peruvian sympatric otariids and discuss mechanisms for competition and/or resource limitation. For this purpose, we analyzed population trajectories of SASL and SAFS in a sympatric breeding site in Punta San Juan, Peru between 2001 and 2019. Wavelet analysis was used to extract trends and derivatives to estimate rates and turning points. Age-class proportions and biomass times series were constructed from weekly counts and evaluated. Both populations show a growth phase and subsequent decline. SAFS started to decline ~2.25 years before and at a rate 1.5 times faster than SASL. Decrease in juvenile age-class suggests that resource limitation is the main contributing factor for current population decline.
Volume
169
Language
English
OCDE Knowledge area
Oceanografía, Hidrología, Recursos hídricos
Zoología, Ornitología, Entomología, ciencias biológicas del comportamiento
Subjects
Scopus EID
2-s2.0-85105729751
PubMed ID
Source
Marine Environmental Research
ISSN of the container
01411136
Sponsor(s)
This study is part of the doctoral dissertation of the first author, developed at the Escuela Doctoral Franco Peruana en Ciencias de la Vida, Universidad Peruana Cayetano Heredia and École Doctorale GAIA Biodiversité, Agriculture, Envrionnement, Terre, Eau, Université de Montpellier, France. Data collection in Punta San Juan was possible thanks to the interinstitutional collaboration agreements between Universidad Peruana Cayetano Heredia, SERNANP – MINAM and AgroRural - MINAGRI. We would like to thank SERNANP for access to Punta San Juan reserve and AgroRural for the use of facilities in the field. We would also like to acknowledge support from the consortium of North American zoos (Chicago Zoological Society, Saint Louis Zoo, Kansas City Zoo and Woodland Park Zoo) that fund the field operations of the Punta San Juan Program which are essential to collect the long term dataset analyzed in this investigation. Most importantly, we thank all the volunteers, interns and personnel of the Punta San Juan Program that have helped collect this valuable information over the years. Finally, we are very grateful to the two anonymous reviewers who contributed towards the improvement of this manuscript.
Sources of information:
Directorio de Producción Científica
Scopus