Abstract
Interspecific interactions are key drivers of individual and population-level fitness in a wide range of animals.However,in marine ecosystems,it is relatively unknown which biotic and abiotic fac-tors impact behavioral interactions between competing species.We assessed the impact of wea-ther,marine productivity,and population structure on the behavioral agonistic interactions be-tween South American fur seals(SAFSs),Arctocephalus australis,and South American sea lions(SASLs),Otaria byronia,in a breeding colony of SAFS.We hypothesized that agonistic interactions between SAFSs and SASLs respond to biotic and abiotic factors such as SAFS population struc-ture,marine productivity,and weather.We found that SASL and SAFS interactions almost always resulted in negative impacts on the social structure or reproductive success of the SAFS colony.SASL adult males initiated stampedes of SAFS and/or abducted and predated SAFS pups.Adult SAFS males abundance and severe weather events were negatively correlated with agonistic inter-actions between species.However,proxies for lower marine productivity such as higher sea sur-face temperature and lower catches of demerso-pelagic fish were the most important predictors of more frequent agonistic interactions between SAFS and SASL.Under the current scenario of de-cline in marine biomass due to global climate change and overfishing,agonistic interactions be-tween competing marine predators could increase and exacerbate the negative impacts of environ-mental change in these species.
基金项目
Rufford Small Grants Foundation(18815-1)
Morris Animal Foundation(D16ZO-413)
维普
万方数据