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Author for correspondence: Juan Antonio De-Anda-Montañez, E-mail: [email protected]
Introduction
Vertical movements have been linked to foraging behaviour and exploration of favourable environmental conditions in several pelagic (Klimley et al., 1993; Musyl et al., 2003; Williams et al., 2015; Thygesen et al., 2016) and demersal fish (Seitz et al., 2003; Peklova et al., 2012, 2014). Vertical movements frequently respond to the distribution of prey, with fish usually moving towards the surface at dusk and sinking at dawn, or vice versa. On the other hand, vertical displacement can also be related to properties that vary across the water column, such as temperature or oxygen concentration, thus limiting their distribution range. As a result, fish susceptibility to a particular fishing gear varies according to water column structure and time of the day (Bone & Moore, 2008; Sims et al., 2008; Abascal et al., 2010; Chiang et al., 2011; Afonso et al., 2014).
Biotelemetry has increased the understanding of the patterns and drivers of these movements, through the use of electronic devices such as pop-up satellite archival tags (PSAT). These are attached externally to fish and record data on depth, temperature and light over a specified period of time. After release, as soon as the tag pops up to the sea surface, it relays data to an Argos satellite. The information recorded is useful to gain a deeper understanding that contributes to better protection and management of fish in both freshwater and marine ecosystems (Thorstad et al., 2013).
Sciaenids are commonly called drums or croakers because of the sound produced with the swim bladder (Ramcharitar et al., 2006). Many species are economically important because their swim bladder is deemed a valued oriental delicacy (Chao, 1978). The totoaba, Totoaba macdonaldi Gilbert (1890), is a large sciaenid fish (up to 2 m) that is endemic to the Gulf of California, Mexico, characterized by late sexual maturity (6–7 years) and a single reproduction event per year. The distribution of the totoaba in the eastern Gulf of California stretches from the Colorado River mouth to the Fuerte River mouth, and along the west coast from the Colorado River mouth to Conception Bay (Arvizu & Chávez, 1972; Flanagan & Hendrickson, 1976).
The...
