Contents lists available at ScienceDirect Journal of Experimental Marine Biology and Ecology journal homepage: www.elsevier.com/locate/jembe Refuge choice specificity increases with predation risk in a rocky reef fish José Anchieta C.C. Nunes a,b, ⁎ , Antoine Leduc c,d , Ricardo J. Miranda a,e , Pedro H. Cipresso f , João P. Alves a , Eduardo Mariano-Neto c , Cláudio L.S. Sampaio g , Francisco Barros a a Laboratório de Ecologia Bentônica, CIENAM, Instituto de Biologia, Universidade Federal da Bahia, Campus Ondina, Salvador, BA CEP 40170-115, Brazil b Laboratório de Ecologia e Conservação Marinha, Centro de Formação de Ciências Ambientais, Universidade Federal do Sul da Bahia, Brazil c Instituto de Biologia, Universidade Federal da Bahia, Campus Ondina, Salvador, BA CEP 40170-115, Brazil d Marine Ecology Laboratory, Department of Oceanography and Limnology, Universidade Federal do Rio Grande do Norte, Av. Via Costeira S/N, Natal, RN CEP 59014- 002, Brazil e National Marine Science Centre, Southern Cross University, Coffs Harbour, NSW 2450, Australia f Projeto Conservação Recifal, Recife, Brazil g Laboratório de Ictiologia e Conservação, U. E. Penedo, Campus Arapiraca, Programa de Pós-graduação em Diversidade Biológica e Conservação nos Trópicos, ICBS, Universidade Federal de Alagoas (UFAL), Maceió, Alagoas, Brazil ARTICLE INFO Keywords: Flight initiation distance Reef fish behaviour Escape microhabitat, ecology of fear Antipredation strategies ABSTRACT Reef ecosystems are structurally complex and characterized by an array of abiotic (e.g., rocks and crevices) and biotic (sessile benthic organisms) physical features, many of which having the potential to act as refuge for prey organisms. Small cryptic reef fish species, including the redlip blenny, Ophioblennius trinitatis, rely on refuges to survive against predators, suggesting that adequate refuge choice is an important part of this species' anti- predator strategy. Here we investigated blennies' selectivity in refuge choice along its ontogeny simulating predation risk in the field and laboratory. Our results revealed that when exposures to a predator model in the field, blennies chiefly fled to only two refuge types, namely crevices and sea urchins, and these choices reflected blennies' ontogeny. Furthermore, blennies' densities and flight-initiation distances were positively and nega- tively correlated with sea urchin densities, respectively, underscoring the refuge role played by this benthic organism. On high risk conditions, the fish translated into faster retreat to shelter and to higher refuge se- lectivity, when compared to low risk. The choices observed in situ were partly similar among initial and terminal phases. These findings suggest that small reef fishes may be selective in their refuge choice even using habitats with high structural complexity. This choice selectivity may be part of an antipredator strategy that considers the relative level of protection offered by the physical features of habitats, along with their conspicuity within rocky reef ecosystems. 1. Introduction Ecologists have long recognized the importance of habitat selection as a mechanism underpinning both species occurrence in a given ha- bitat and their propensity to coexist in communities (MacArthur and Pianka, 1966; Rosenzweig, 1981; Pereira et al., 2015). In predator-prey interactions, refuge selection may be thought as a form of habitat choice, which allow preys to persist in the same habitat as their pre- dators (Stankwich and Blumstein et al., 2005). Given refuges may drastically improve a prey's survival, important pressures on prey should exist to choose adequately which physical structures are used as refuge (Hixon and Beets, 1993). Considering many mobile preys living in structurally complex habitats (e.g., rainforests, coral and rocky reefs), multiple types of re- fuges may potentially exist. Examples in terrestrial systems include tree holes, branches and bushes, and in the oceans, burrows, rocks, crevices and benthic organisms. While this is common knowledge, we have scant information on the mechanisms by which preys select among multiples available refuges, and for preys that do not build their own refuge, whether these are selective in the type of refuge they use under risk. Recently, Cooper and Samia (2018) proposed a refuge selection model for typical mobile preys. This theoretical model provides a me- chanistic understanding on how prey may select against multiple available refuges (i.e. considering relative distance of predator and re- fuges, level of risk imposed on prey to attain a given refuge), it does not address, per se, whether qualitatively different types (i.e., different https://doi.org/10.1016/j.jembe.2019.151207 Received 2 January 2019; Received in revised form 11 July 2019; Accepted 10 August 2019 ⁎ Corresponding author at: Laboratório de Ecologia Bentônica, CIENAM, Instituto de Biologia, Universidade Federal da Bahia, Campus Ondina, Salvador, BA CEP 40170-115, Brazil. E-mail address: anchietanunesba@gmail.com (J.A.C.C. Nunes). Journal of Experimental Marine Biology and Ecology 520 (2019) 151207 0022-0981/ © 2019 Elsevier B.V. All rights reserved. T