Deep-sea echinoderm oxygen consumption rates and an interclass comparison of metabolic rates in Asteroidea, Crinoidea, Echinoidea, Holothuroidea and Ophiuroidea

Abstract

SUMMARYEchinoderms are important components of deep-sea communities because of their abundance and the fact that their activities contribute to carbon cycling. Estimating the echinoderm contribution to food webs and carbon cycling is important to our understanding of the functioning of the deep-sea environment and how this may alter in the future as climatic changes take place. Metabolic rate data from deep-sea echinoderm species are, however, scarce. To obtain such data from abyssal echinoderms, a novel in situ respirometer system, the benthic incubation chamber system (BICS), was deployed by remotely operated vehicle (ROV) at depths ranging from 2200 to 3600m. Oxygen consumption rates were obtained in situ from four species of abyssal echinoderm (Ophiuroidea and Holothuroidea). The design and operation of two versions of BICS are presented here, together with the in situ respirometry measurements. These results were then incorporated into a larger echinoderm metabolic rate data set, which included the metabolic rates of 84 echinoderm species from all five classes (Asteroidea, Crinoidea, Echinoidea, Holothuroidea and Ophiuroidea). The allometric scaling relationships between metabolic rate and body mass derived in this study for each echinoderm class were found to vary. Analysis of the data set indicated no change in echinoderm metabolic rate with depth (by class or phylum). The allometric scaling relationships presented here provide updated information for mass-dependent deep-sea echinoderm metabolic rate for use in ecosystem models, which will contribute to the study of both shallow water and deep-sea ecosystem functioning and biogeochemistry.Supplementary material available online at

Recovery of Holothuroidea population density, community composition, and respiration activity after a deep‐sea disturbance experiment

“…Brown et al unpubl.). Briefly, the “benthic incubation chamber system 3” (BICS3) (Hughes et al ) was attached to the GEOMAR Ocean elevator (Linke ) and lowered to the seafloor. Holothuroidea were collected individually with the ROV Kiel 6000 and placed individually in three respiration chambers.…”

“…Many holothurian species are large in comparison to other abyssal benthic invertebrates and can therefore be counted and identified from images with comparative ease (Durden et al 2016). Holothuroidea are also mobile, with some species moving > 100 cm h 21 over the seafloor (Jamieson et al 2011) and some species having the capacity to swim (Miller and Pawson 1990;Rogacheva et al 2012). Holothuroidea can respond to fresh phytodetritus deposition events with large-scale recruitment within a year .…”

Differences in the carbon flows in the benthic food webs of abyssal hill and plain habitats

“…Since the SCOC measurements do not include megafauna, megafaunal respiration was removed from this constraint in the updated models. The respiration for each megafaunal feeding type was constrained using the minimum and maximum mass specific respiration rates published by Hughes et al () for deep‐sea ophiuroids and holothurians, since these taxa are abundant at PAP. These rates were converted to carbon equivalents using a respiration quotient of 1 (Glud ), resulting in a constraint range of 0.00015–0.00707 d −1 (in the original model this was 0.00012–0.00591 d −1 ).…”

Spatial distribution patterns in macrobenthos along a latitudinal transect at the deep-sea observatory HAUSGARTEN

“…Data on the lifespan of most deep-sea creatures is generally missing. However, decreasing metabolic rates with increasing water depth should be reflected in the longer lifespan of bathyal and abyssal organisms compared to their shallow-water relatives (Childress and Mickel, 1985;Hughes et al, 2011).…”