Diel vertical migration of sablefish (Anoplopoma fimbria)

Abstract

To investigate their diel vertical migration (DVM), 599 sablefish (Anoplopoma fimbria) were implanted with electronic archival tags in the Gulf of Alaska, Aleutian Islands, and the eastern Bering Sea. Of these tags, 98 were recovered with usable depth data (7,852,773 recordings representing 81,233 days) that we used to identify DVM and to classify DVM into one of two types: normal DVM (rise from the bottom during nighttime) and reverse DVM (rise from the bottom during daytime). The results of our study highlight three important attributes of DVM for sablefish. First, all tagged sablefish carried out DVM, although the occurrence was intermittent (26% of the days with usable data) and most commonly for short durations (10 days or less). Second, bottom depth for normal DVM was about 78 m shallower than for reverse DVM. Third, normal DVM occurred most often in fall and least often in spring, whereas this high/low pattern was shifted about 3 months later for reverse DVM; reverse DVM occurred most often in winter and least often in summer. Normal DVM likely occurred to increase foraging opportunity (e.g., nightly shift to match depth of prey). Reverse DVM more commonly occurred during winter and may represent an increase in foraging by sablefish during the daytime to compensate for decreased pelagic resources. The default foraging strategy for sablefish may be benthic because of the uncertainty of vertically migrating to a location where the occurrence of prey is not guaranteed; sablefish may invoke DVM when the non‐DVM foraging benefit is reduced.

Diurnal vertical movements in black sea bass (Centropristis striata): Endogenous, facultative, or something else?

“…Active movements during the daytime followed by their cessation at night, observed at both the individual and group scale (Figs. 1, 4), are strongly suggestive of an endogenous cycle, substantially less plastic than observed for other demersal (Humphries et al 2017, Sigler andEchave 2019) or pelagic species (Schaefer andFuller 2010, Andrzejaczek et al 2019). Although a field trial cannot establish circadian free-running cycles, the strong correspondence between movement and sun altitude points to the likelihood of a cycle entrained to light, a common zeitgeber in endogenous activity rhythms (Godin 1981, Neilson andPerry 1990).…”

“…In the field, such manipulations are not possible and, in their place, circumstantial evidence is advanced on the adaptive consequences of diel movements including prey tracking, predator avoidance, stationkeeping, navigation, courtship and spawning, sleeping, and energetic refuge (Neilson and Perry 1990, Reebs 2002, Arostegui et al 2017). Longduration biotelemetry and archival tagging studies increasingly point to behaviors that are facultative rather than rigid: those which, for weeks and months, can be remarkably persistent, but, when ecological circumstances change, are suddenly disrupted and altered (Nichol and Somerton 2002, Fox and Bellwood 2011, Nichol et al 2013, Sigler and Echave 2019.…”

Integrating Diel Vertical Migrations of Bioluminescent Deep Scattering Layers Into Monitoring Programs

“…Moreover, a cabled monitoring module (i.e., TempoMini) evidenced inertial and tidal rhythms in communities of deep hydrothermal vents in both the NE Pacific and Mid-Atlantic (Cuvelier et al, 2014(Cuvelier et al, , 2017Lelièvre et al, 2017). Finally, electronic tags have been applied to migrating deep-water predators (i.e., sablefish Anoplopoma fimbria individuals reported between the upper subsurface layer and depths down to 1,250 m, with mean depth differences between day and night reaching 250 m; Goetz et al, 2018;Sigler and Echave, 2019), showing distinct patterns that potentially depend on prey availability (i.e., both night ascending and, inversely, night descending). A more comprehensive review of similar case-studies and advances in applications of telemetry technologies in marine ecology was provided by Hussey et al (2015).…”

The potential of video imagery from worldwide cabled observatory networks to provide information supporting fish-stock and biodiversity assessment

“…Recent studies have proposed different mechanisms for controlling the temporal patterns of sablefish movements along the seafloor and through the water column. Although in Barkley Canyon, British Columbia, sablefish movements seem to be ruled mainly by tidal cycles (Doya et al, 2014;Matabos et al, 2014;Chatzievangelou et al, 2016), in other regions of the NE Pacific, diel vertical migrations of subpopulations have been attributed to the displacement patterns of their prey (Goetz et al, 2018) and also to the intensity of their nearbottom foraging behaviour (Sigler and Echave, 2019). However, other studies have not identified a single major environmental control over sablefish population movements (Orsi et al, 2006).…”