Diel changes in small-scale vertical distribution of hyperbenthic mysids

Abstract

SARSIA KAARTVEDT, STEIN 1985 12 30. Diel changes in small-scale vertical distribution of hyperbenthic mysids. -Sarsia 70: 287-295 Bergen. ISSN 0036-4827.Erythrops serrata (G.O. SARS), Boreomysis megalops G.O. SARS, Leptomysis gracilis (G.O. SARS) and Lophogaster typicus M. SARS were studied at 150 m depth in Fanafjorden, western Norway in April, June, September, and December 1979. Sampling was performed with hyperbenthic sledges in intervals of 0-80 cm and 30-80 cm above the sediment. During daylight all species were concentrated in immediate vicinity of the sediment. During darkness E. serrata performed increased swimming activity near the bottom. A part of the population of B. megalops always undertook vertical migration at night. Distribution of the remaining hyperbenthic part was less stratified than during daylight. A substantial portion of vertically migrating individuals returned to depth before sunrise. Almost the entire population of L. gracilis and L. typicus left the hyperbenthic region prior to sunset, and returned after sunrise. Approaching sunset distributional changes first occurred for L. typicus (1-2 hours prior to sunset), followed by L. gracilis and later by B. megalops and E. serrata. At twilight conditions, occasionally a transition state between daylight-and night-distribution was found, most prominent in L. typicus in the afternoon.

Diel activity patterns in deep-living cumaceans and amphipods

“…was less extensive than has been proposed for other benthic invertebrates (Chapman et al 1975), but in accordance with what was found for mysids in the LITERATURE CITED same locality (Kaartvedt 1985). Since the large-eyed mysids, and the cumaceans and amphipods whlch have more poorly developed eyes, responded to changes in light intensity in the same time interval (0 to 2 h prior to sunset), any differences in exact time for initiation of vertical migrations may rather be speciesspecific than governed by the accomplishment of visual organs.…”

“…Aberdeen University Press, Aberdeen, mates of the population as as the number of Corey, S. (1970 3) indicate that the main part of the population remained relatively close to the substrate during darkness. This picture differs from the results on the mysids in the same locality (Kaartvedt 1985). In general, mysids disappeared from the hyperbenthic region at night.…”

Bathymetric distribution of Mysidacea in fjords of western Norway

“…1, Table 1). Some of the mysids, especially those living shallower than about 300 m, are known to undertake diurnal vertical migrations (Kaartvedt 1985, 1989, Fossd 1986). As a consequence, the number of individuals caught during night and day may differ considerably.…”

“…Autecological studies have been performed on Boreomysis arctica by Jakupsstovu (1970), Lophogaster typicus by Bjerkestrand (1979) and Praunus flexuosus by Attramadal (1980). Ecological and behavioural studies have been performed on various species (Matthews & Bakke 1977, Attramadal et al 1985, Fossd 1985, Kaartvedt 1985, 1989 and biochemical aspects prin~arily on B. arctica by Brattelid & Matthews (1978) and Bdmstedt (1978Bdmstedt ( , 1981. Mattson (1981) analyzed the importance of mysids as food for fish on prawn trawl grounds.…”

Ecology and life history traits of the benthopelagic mysid Boreomysis oparva from the eastern tropical Pacific oxygen minimum zone

“…Many Boreomysis spp. are considered meso-or bathypelagic from pelagic sampling, though most species of Mysidacea live in close association with the ocean bottom (Fossa 1985, Kaartvedt 1985 One of the important morpholog~.cal features of Boreomysjs is 7 pairs of lamellae in the females. Since larvae are provided with oxygen by the female moving the lamellae, Boreornysis spp., or other genera with 7 pairs of lamellae, may be able to provide more oxygen to their larvae.…”