Ontogeny of behaviour in larvae of marine demersal fishes

Abstract

The development of behaviours that are relevant to larval dispersal of marine, demersal fishes is poorly understood. This review focuses on recent work that attempts to quantify the development of swimming, orientation, vertical distribution and sensory abilities. These behaviours are developed enough to influence dispersal outcomes during most of the pelagic larval stage. Larvae swim in the ocean at speeds similar to the currents found in many locations and at 3-15 body lengths per second (BL s -1 ), although, based on laboratory measurements, species from cold environments swim slower than those from warm environments. At least in warm-water species, larvae swim in an inertial hydrodynamic environment for most of their pelagic period. Unfed swimming endurance is [10 km from about 8-10 mm, and reaches more than 50 km before settlement in several species. Larval fishes are efficient swimmers. In most species, a large majority of larvae have orientated swimming in the ocean, but the precision of orientation does not improve with growth. Swimming direction of the larvae frequently changes ontogenetically. Vertical distribution changes ontogenetically in most species, and both ontogenetic ascents and descents are found. Development of schooling is poorly understood, but it may influence speed, orientation and vertical distribution. Sensory abilities (hearing, olfaction, vision) form early, are well developed and are able to detect cues relevant to orientation for most of the pelagic larval stage. All this indicates that the passive portion of the pelagic larval duration will be short, at least in most warm-water species, and that behaviour must be taken into account when considering dispersal, and in particular in dispersal models. Although quantitative information on the ontogeny of some behaviours is available for a relatively small number of species, more research in this field is required, especially on species from colder waters.

Shoreward swimming boosts modeled nearshore larval supply and pelagic connectivity in a coastal upwelling region

“…Nearshore supply increases approximately linearly with "maximum distance swam," the maximum possible distance larvae could have swum if swimming continued uninterrupted from onset until death at 45 days. This distance is similar to the endurance statistic reported for laboratory measurements of fish larvae (Leis, 2010). A least squares, simple linear regression yields: normalized-nearshore-larval-supply = 0.02 + 0.004 * maximum-distanceswam, with distance in km.…”

“…Horizontal swimming, known to be important for adults of many species, is increasingly invoked as a method to regulate retention and dispersal by allowing larvae to navigate toward suitable settlement sites near the end of the larval phase Cowen and Sponaugle, 2009;Leis, 2006;Staaterman et al, 2012;Staaterman and Paris, 2014). The effective in situ swimming ability of larvae over their total larval development period is unknown for most species (Giangrande et al, 2017;Leis, 2010;Queiroga and Blanton, 2005). In the laboratory, pre-settlement stage fish larvae typically swim less than 5 cm s −1 (Blaxter, 1986) and can maintain swimming speeds of…”

“…Autocorrelated directional horizontal swimming can also increase settlement and the extent of connectivity (Berenshtein et al, 2018). Despite these results, there is general uncertainty in the role that horizontal swimming plays in regulating retention and dispersal (Leis, 2006(Leis, , 2010Metaxas, 2001). Even when horizontal currents can easily overwhelm the typical swimming speeds of larvae, horizontal swimming may still have a large impact on settlement.…”

“…In contrast, some form of directed swimming may be maintained, however, for most, if not all, of their PLD. The combined effects of ocean advection and vertical and horizontal swimming on dispersal are unclear, as they may interact in the variable pelagic environment in unpredictable ways (Leis, 2010;Metaxas, 2001).…”

Ontogenetic development in the morphology and behavior of loach (Misgurnus anguillicaudatus) during early life stages

“…The ability to swim is critical for larval survival during the transition to exogenous feeding (Osse et al, 1997;Gisbert et al, 2002;Morioka et al, 2009). Loach become demersal immediately after hatching and do not have a pelagic larval stage, which differs from many teleost fi sh species (Leis, 2010). The long inactive period observed in loach larvae and juveniles in the present study is consistent with reports in some other demersal fi sh species, such as Limanda yokohamae (Fukuhara, 1988) and Merluccius merluccius (Bjelland and Skiftesvik, 2006).…”