We deployed 2 porpoise (Phocoena phocoena) carcasses at bathyal depth (2555 to 2710 m) in the Porcupine Seabight, NE Atlantic for periods of 1 wk and 6 mo respectively. Consumption rates of 0.085 and 0.078 kg h -1 were similar to those observed at abyssal depths in the Atlantic, and 1 order of magnitude slower than at bathyal depth in the Pacific. A distinct succession of scavenging species was observed at both carcasses: the abyssal grenadier Coryphaenoides armatus and the cusk eel Spectrunculus grandis numerically dominated the initial phase of carcass consumption and, once the bulk of the soft tissue had been removed (by Day 15), were succeeded by the squat lobster Munidopsis crassa. The blue hake Antimora rostrata and amphipod numbers were unexpectedly low, and consumption was attributed largely to direct feeding by C. armatus. The interaction of a crustacean prey species (M. crassa) and cephalopod predator (Benthoctopus sp.) was observed for the first time, revealing that large food falls also attract secondary predators that do not utilise the food fall directly. The staying time of a single parasitised C. armatus (18 h) greatly exceeded previous estimates (≤ 8 h). This study describes the first large food fall to be monitored at high frequency over a 6 mo period, and the first observations of a large food fall at bathyal depth in the NE Atlantic. It enables direct comparison with similarly sized food falls at abyssal depth, much larger megacarrion falls, and similar studies differing in geographic location, in particular those carried out under Pacific whale migration corridors.

We report the results from the first experimental study of the fate of whale and wood remains on the Antarctic seafloor. Using a baited free-vehicle lander design, we show that whale-falls in the Antarctic are heavily infested by at least two new species of bone-eating worm, Osedax antarcticus sp. nov. and Osedax deceptionensis sp. nov. In stark contrast, wood remains are remarkably well preserved with the absence of typical wood-eating fauna such as the xylophagainid bivalves. The combined whale-fall and wood-fall experiment provides support to the hypothesis that the Antarctic circumpolar current is a barrier to the larvae of deep-water species that are broadly distributed in other ocean basins. Since humans first started exploring the Antarctic, wood has been deposited on the seafloor in the form of shipwrecks and waste; our data suggest that this anthropogenic wood may be exceptionally well preserved. Alongside the new species descriptions, we conducted a comprehensive phylogenetic analyses of Osedax, suggesting the clade is most closely related to the frenulate tubeworms, not the vestimentiferans as previous reported.

The effects of thermal acclimation were investigated in the common carp Cyprinus carpio L. Acclimation and acute temperature effects were tested during ontogeny from larval [9.5 mm total length (L)] to juvenile (69.0 mm L) stages and between 8 and 21 degrees C. The myosin heavy chain (MHC) composition, myofibrillar Mg(2+)-Ca(2+)-ATPase activity, and muscle strains showed significant thermal acclimation effects. MHCs were only expressed in an acclimation temperature-dependent fashion in fish longer than 37 mm. During fast starts, the temperature had a significant effect on the white muscle strain (33% increase and 50% decrease with increasing acclimation and acute temperature, respectively) and contraction duration (25% decrease with increasing acute temperature). Increases in hydrodynamic efficiency (0.19 to 0.38) and hydrodynamic power requirements (Q(10) = 3.2) occurred with increasing acute temperature (10 to 20 degrees C). Competing hypotheses about the evolutionary significance of the temperature acclimation response were tested. Acclimation extended the temperature range for fast-start behavior, but no improvements in performance at the whole animal level were found between 8 and 21 degrees C.

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The term vulnerable marine ecosystem (VME) was introduced to facilitate the spatial management of deep-seas, identifying those habitats vulnerable to anthropogenic disturbance, such as trawling. Consistent interpretation of the VME definition has been hampered by an underlying paucity of knowledge about the nature and distribution of deep-sea habitats. Photographic and video platforms yield data rich, quantifiable imagery to address these knowledge gaps. A low-cost towed benthic video sled has been used to investigate deep-sea habitats and trawling impacts in west Greenland. A review of imagery from multiple cruises highlighted an area where benthic megafauna contributes to notable structural complexity on the continental slope of the Toqqusaq Bank. Quantitative analysis of imagery from this area provides the first description of a soft coral garden habitat and other communities. The coral garden and observed densities are considered in relation to the VME guidelines (FAO, 2009) and wider literature. The study proposes a 486 km 2 area spanning ∼60 km of continental slope as a VME. This has direct implications for the management of economically important deep-sea trawl fisheries, which are immediately adjacent. This furthers our knowledge and understanding of VMEs in North Atlantic, in a previously understudied region and demonstrates the utility of a low-cost video sled for identifying and describing VMEs.