Shifting feeding behaviour of deep-sea buccinid gastropods at natural and simulated food falls

Abstract

The deep sea is a low food input envir onment, hence large food falls from the surface waters are important in suppor ting a wealth of scavenging deep-sea fauna. The pr obability of observing such events is ver y low, due to their unpr edictable and short-lived nature. The video system of a cabled obser vatory installed within a cold seep clam field in Sagami Bay (1100 m depth; Central Japan) recorded a rare event. We observed a fish dying directly in front of the camera and being immediately perceived and preyed upon by Buccinum yoroianum (Neo gastropoda: Buccinidae), while still alive. Up to 76 large snails responded to the fish and consumed the carcass within ~8 h, with no inter vention by decapod cr ustaceans. There was only small par ticipation of eelpouts (Zoarcidae). For comparison, we report on supplementary findings from a different area and depth of the Pacific Ocean. These obser vations were recorded by a baited camera lander which simulated a food fall. W ithin 6 h, the buccinid Tacita zenkevitchi aggregated on the bait, competing with fishes. These observations confirm that deep-sea buccinids can shift their feeding behaviour between active pr edation and scavenging. Our perception, however, seems conditioned by the observational methodology we use: buccinids may appear as scavengers when using photography (e.g. by baited landers) pr oducing single snapshots in time, or as pr edators when observed in a natural setting and video-taped continuously with a cabled observatory.

Faunal activity rhythms influencing early community succession of an implanted whale carcass offshore Sagami Bay, Japan

“… Taxonomical Unit Movement Life Habit Trophic Habit References N % P Var. Echinodermata Pannychia moseleyi Walker Epibenthic Detritivore 47 , 48 62 0.86 — — — Echinothurioida Walker Epibenthic Detritivore 49 21 0.29 — — — Solaster paxillatus Walker Epibenthic Scavenger (and predator) 50 73 1.02 — — — Ophiurida Walker Endobenthic Detritivore 51 755 10.52 — — — Mollusca Buccinum yoroianum Walker Epibenthic Scavenger (and predator) 22 , 52 9 0.13 — — — Arthropoda Bathynomus doederleinii Swimmer Endobenthic Scavenger 53 349 4.86 — — — Macrocheira kaempferi Walker Epibenthic Scavenger (and predator) 43 , 54 1002 …”

Geophysical and geochemical controls on the megafaunal community of a high Arctic cold seep

“…Similarly, certain gastropods were seen perched atop carbonate structures and it is unlikely that the hardness of the concretions or their sheltering properties are of particular significance for this shelled group of animals. Rather, it is probably the dense colonization of these structures by various animals that accounts for this association with carbonates, since the observed gastropods likely also have predatory or scavenging feeding styles (Aguzzi et al, 2012).…”

“…The shells of large-bodied chemosymbiotic bivalves (thyasirids and vesicomyids) have been recovered in cores from the pingo study site (Åström et al, 2017a), Vestnesa Ridge (Ambrose et al, 2015;Hansen et al, 2017;Sztybor and Rasmussen, 2017) and methane seep deposits on the Gakkel Ridge (Kim et al, 2006) and in the Laptev Sea (Sirenko et al, 1995). Shells from the pingo site have been estimated to be up to 7000-14 000 years old (M. Carroll, unpublished data), and based on the Vestnesa and Gakkel Ridge samples, the extinction event for these animals has been estimated to have taken place around 15 000 years ago (Ambrose et al, 2015;Hansen et al, 2017;Kim et al, 2006;Sztybor and Rasmussen, 2017). This coincides with deglaciation following the Heinrich H1 cold event and the accompanying environmental changes, including extensive releases of methane such as is hypothesized to have created the pingos at the study site .…”

High-Frequency Patterns in the Abundance of Benthic Species near a Cold-Seep – An Internet Operated Vehicle Application

“…Sablefish found at these depths are most commonly adult predators with demersal life habits [ 27 , 49 ], in contrast to younger pelagic individuals [ 50 – 51 ]. As active swimmers preying on smaller benthic fish and invertebrates [ 50 , 52 ], adult sablefish could be expected to react positively to increases of current velocity that lead to odor transport [ 53 – 54 ]. Sablefish have characteristically low-affinity hemoglobin, a characteristic which favors their active swimming, predatory life habits, but may result in reduced oxygen uptake within hypoxic waters [ 55 ].…”