Inverse vertical migration and feeding in glacier lanternfish (Benthosema glaciale)

Abstract

A bottom-mounted upward-facing 38-kHz echo sounder was deployed at ~400 m and cabled to shore in Masfjorden (~60°52′N, ~5°24′E), Norway. The scattering layers seen during autumn (September–October) 2008 were identified by trawling. Glacier lanternfish (Benthosema glaciale) were mainly distributed below ~200 m and displayed three different diel behavioral strategies: normal diel vertical migration (NDVM), inverse DVM (IDVM) and no DVM (NoDVM). The IDVM group was the focus of this study. It consisted of 2-year and older individuals migrating to ~200–270 m during the daytime, while descending back to deeper than ~270 m during the night. Stomach content analysis revealed increased feeding during the daytime on overwintering Calanus sp. We conclude that visually searching glacier lanternfish performing IDVM benefit from the faint daytime light in mid-waters when preying on overwintering Calanus sp.

Seasonal variations in vertical migration of glacier lanternfish, Benthosema glaciale

“…Results from the physical oceanography, zooplankton, and trawling studies from these field campaigns are used in the interpretations, but are presented elsewhere (Staby et al 2011; Dypvik et al 2012). …”

“…The depth distribution of myctophids is size dependent with larger fish distributed deeper than smaller individuals (Willis and Pearcy 1980; Gartner et al 1987; Dypvik et al 2012). Therefore, differences in conspicuousness (Hays et al 1994), vision (capabilities) for detecting prey (Warrant and Locket 2004), internal state (satiation and hunger) (Cailliet and Ebeling 1990; Staby et al 2011), and motivation (Rosland and Giske 1997; Busch and Mehner 2012) are expected to result in a mixture of migration patterns, which may occur simultaneously.…”

Predator-Prey Games in Multiple Habitats Reveal Mixed Strategies in Diel Vertical Migration

“…Diel vertical migration (DVM) is a behavior exhibited by a large number of marine species, from plankton to marine mammals. The most conspicuous of these are the migrations carried out by mesopelagic fish (O'Driscoll et al 2009;Dypvik et al 2012), krill (Onsrud et al 2004;Zhou and Dorland 2004), copepods (McLaren 1963;Frost and Bollens 1992;Hays et al 2001), and jellyfish (Kaartvedt et al 2007). These migrations are particularly evident in the daily variations in the depth of the deep scattering layer (Barham 1966;Isaacs et al 1974), the signature of aggregations of acoustically reflective marine organisms that typically alternate between a surface layer during nighttime hours and a deeper layer during daylight hours.…”

Microstructure of the otoliths of the glacier lanternfish, Benthosema glaciale

“…Diel vertical migrations to surface layers at night have been observed for this species in different areas (Halliday 1970;Kinzer 1977;Roe and Badcock 1984;Sameoto 1988), while the inverse diel vertical migration has only recently been documented in B. glaciale: migrations to 200-270 m take place during the day followed by descents back to waters deeper than 270 m during the night (Kaartvedt et al 2009;Dypvik et al 2012). In the Flemish Cap, B. glaciale has been found between 300 and 650 m depth during daylight hours, and a portion of the population probably migrates to the surface at night (García-Seoane et al 2013).…”