Seasonal variations in vertical migration of glacier lanternfish, Benthosema glaciale
نویسندگان
چکیده
The seasonal variations in glacier lanternfish (Benthosema glaciale) vertical distribution and diel vertical migration (DVM) were studied by use of a bottom-mounted upward-facing 38 kHz echo sounder deployed at 392 m depth and cabled to shore in Masfjorden (~60°52'N, ~5°24'E), Norway. Acoustic data from July 2007-October 2008 were analyzed, and scattering layers below ~220 m during daytime were attributed to glacier lanternfish based on net sampling in this, and previous studies, as well as from analysis of the acoustic data. At these depths, three different diel behavioral strategies were apparent: normal diel vertical migration (NDVM), inverse DVM (IDVM), and no DVM (NoDVM). NoDVM was present all year, while IDVM was present in autumn and winter, and NDVM was present during spring and summer. The seasonal differences in DVM behavior seem to correlate with previously established seasonal distribution of prey. We hypothesize that in regions with seasonally migrating zooplankton, such as where calanoid copepods overwinter at depth, similar plasticity in DVM behavior might occur in other populations of lanternfishes.
منابع مشابه
Inverse vertical migration and feeding in glacier lanternfish (Benthosema glaciale)
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 migrati...
متن کاملEarly development of eye and retina in lanternfish larvae.
The morphological characteristics of the eyes and the retinae of lanternfish larvae of Lampanyctus crocodilus, Benthosema glaciale, and Myctophum punctatum were analyzed in pre-flexion, flexion, and post-flexion stages. Pre-flexion larvae of L. crocodilus, the species with the shallowest depth distribution, had spherical eyes located antero-laterally on a strongly laterally-compressed head, sug...
متن کاملEffect of salt and alkaline on the physicochemical properties of the protein isolates extracted from lanternfish (Benthosema pterotum)
The aim of this study was to evaluate the effect of alkaline and NaCl on functional properties of protein isolated from Lanternfish (Benthosema pterotum). In this study, extraction of fish protein was performed at different concentrations of NaCl (0.5%, 1.5%, 3% and 4.5%) at pHs 10 and 12. The results showed alkaline treatment improved the functional properties and the recovery yield of protein...
متن کاملCryptic speciation in the mesopelagic environment: molecular phylogenetics of the lanternfish genus Benthosema.
The presence of morphologically identical individuals that are genetically divergent, known as cryptic species, is a phenomenon that is likely to be of importance at the theoretical level, for speciation studies, and at the applied level, for management purposes. Cryptic species are probably common in the marine environment, and they have been described in a variety of habitats. Here we present...
متن کاملDiet and trophic position of Leach’s storm-petrel Oceanodroma leucorhoa during breeding and moult, inferred from stable isotope analysis of feathers
We combined conventional dietary sampling (2002) with stable isotope analysis of nitrogen (δ15N) and carbon (δ13C) in feathers of Leach’s storm-petrels Oceanodroma leucorhoa (2001 and 2002) to investigate temporal, sexand age-related variation in diet and trophic position, at Baccalieu Island, Newfoundland, Canada. Nestlings are fed mainly fish and crustaceans (ca. 90 and 9% by mass, respective...
متن کامل