Top predators induce habitat shifts in prey within marine protected areas

• Published in: Oecologia Vol. 190; no. 2; pp. 375 - 385
• Main Authors: Bond, M. E., Valentin-Albanese, J., Babcock, E. A., Heithaus, M. R., Grubbs, R. D., Cerrato, R., Peterson, B. J., Pikitch, E. K., Chapman, D. D.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Science + Business Media 01-06-2019; Springer Berlin Heidelberg; Springer Nature B.V
• Subjects: Anti-predator behavior; Aquatic habitats; BEHAVIORAL ECOLOGY – ORIGINAL RESEARCH; Benthic communities; Benthos; Biomedical and Life Sciences; Cascades; Crypsis; Dasyatidae; Ecology; Environmental changes; Fish populations; Habitats; Hydrology/Water Resources; Interactions; Interspecific relationships; Life Sciences; Marine fishes; Marine parks; Marine protected areas; Nature reserves; Plant Sciences; Populations; Potential resources; Predation; Predator-prey interactions; Predators; Prey; Protected areas; Reefs; Restoration; Sharks; Surveying; Underwater; Visibility; Behaviorally mediated interactions; Marine reserves; Risk effects; Reef sharks; Stingrays
• ISSN: 0029-8549; 1432-1939
• DOI: 10.1007/s00442-019-04421-0

Emerging conservation efforts for the world’s large predators may, if successful, restore natural predator–prey interactions. Marine reserves, where large predators tend to be relatively common, offer an experimental manipulation to investigate interactions between large-bodied marine predators and their prey. We hypothesized that southern stingrays—large, long-lived and highly interactive mesopredators—would invest in anti-predator behavior in marine reserves where predatory large sharks, the primary predator of stingrays, are more abundant. Specifically, we predicted southern stingrays in marine reserves would reduce the use of deep forereef habitats in the favor of shallow flats where the risk of shark encounters is lower. Baited remote underwater video was used to survey stingrays and reef sharks in flats and forereef habitats of two reserves and two fished sites in Belize. The interaction between “protection status” and “habitat” was the most important factor determining stingray presence. As predicted, southern stingrays spent more time interacting with baited remote underwater videos in the safer flats habitats, were more likely to have predator-inflicted damage inside reserves, and were less abundant in marine reserves but only in the forereef habitat. These results are consistent with a predation-sensitive habitat shift rather than southern stingray populations being reduced by direct predation from reef sharks. Our study provides evidence that roving predators can induce pronounced habitat shifts in prey that rely on crypsis and refuging, rather than active escape, in high-visibility, heterogeneous marine habitats. Given documented impacts of stingrays on benthic communities it is possible restoration of reef shark populations with reserves could induce reef ecosystem changes through behavior-mediated trophic cascades.