Repeated, long-distance migrations by a philopatric predator targeting highly contrasting ecosystems

• Published in: Scientific Reports
• Main Authors: Lea, James S. E., Mucientes, Gonzalo, Shivji, Mahmood S.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Nature Publishing Group 2015
• Subjects: Northwest Atlantic
• Online Access: http://hdl.handle.net/10261/124501; https://doi.org/10.1038/srep11202

11 páginas, 5 figuras.-- James S. E. Lea . et al.-- This work is licensed under a Creative Commons Attribution 4.0 International License Long-distance movements of animals are an important driver of population spatial dynamics and determine the extent of overlap with area-focused human activities, such as fishing. Despite global concerns of declining shark populations, a major limitation in assessments of population trends or spatial management options is the lack of information on their long-term migratory behaviour. For a large marine predator, the tiger shark Galeocerdo cuvier, we show from individuals satellite-tracked for multiple years (up to 1101 days) that adult males undertake annually repeated, round-trip migrations of over 7,500 km in the northwest Atlantic. Notably, these migrations occurred between the highly disparate ecosystems of Caribbean coral reef regions in winter and high latitude oceanic areas in summer, with strong, repeated philopatry to specific overwintering insular habitat. Partial migration also occurred, with smaller, immature individuals displaying reduced migration propensity. Foraging may be a putative motivation for these oceanic migrations, with summer behaviour showing higher path tortuosity at the oceanic range extremes. The predictable migratory patterns and use of highly divergent ecosystems shown by male tiger sharks appear broadly similar to migrations seen in birds, reptiles and mammals, and highlight opportunities for dynamic spatial management and conservation measures of highly mobile sharks Funding for this study was provided by the Guy Harvey Ocean Foundation, Guy Harvey Research Institute, the Shark Foundation (Hai Stiftung), and the Bermuda Shark Project. Funding for data analysis was provided by the UK Natural Environment Research Council (NERC) ‘Oceans 2025’ Strategic Research Programme in which D.W.S. is a principal investigator, a Fundação para a Ciência e a Tecnologia (FCT) grant (PTDC/MAR/100345/2008) to N.Q. and D.W.S., and an FCT grant ...