Seasonal activity including physiology and biochemistry of Cucumaria georgiana and Heterocucumis steineni at Rothera Research Station, 2020-2022
GB/NERC/BAS/PDC/02249
Abstract:
This dataset comprises measurements of faecal egestion, seasonal metabolism, and biomass changes. A longitudinal study was conducted around Adelaide Island (Rothera Research Station) within Ryder Bay to investigate the distribution, seasonal activity, and role in benthic-pelagic coupling of two suspension-feeding holothurian species, Cucumaria georgiana and Heterocucumis steineni. This work links organismal physiology with the ecosystem service of carbon transfer in a rapidly changing polar region, offering insights relevant to marine ecology, physiology, biogeochemistry, and climate-impact research at high latitude where carbon cycles are of global significance.
This study was funded by core funding to UKRI NERC-BAS.
Citation:
Marlow, J., Frontier, N., Rad-Menendez, C., Peck, L.S., & Morley, S.A. (2026). Seasonal activity including physiology and biochemistry of Cucumaria georgiana and Heterocucumis steineni at Rothera Research Station, 2020-2022 (Version 1.0) [Data set]. NERC EDS UK Polar Data Centre. https://doi.org/10.5285/bef78e96-bc7e-40c3-b614-2f125fe41893
Access Data
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License
| Access: | This dataset is under embargo until publication of the associated paper. |
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| Use: | This data is governed by the NERC data policy http://www.nerc.ac.uk/research/sites/data/policy/ and supplied under Open Government Licence v.3 http://www.nationalarchives.gov.uk/doc/open-government-licence/version/3/. |
Basic Information
| Creation Date: | 2026-07-29 |
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| Dataset Progress: | Complete |
| Dataset Language: | English |
| ISO Topic Categories: |
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| Parameters: |
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Additional Information
| Reference: | Robert M Holmes, Alain Aminot, Roger Kérouel, Bethanie A Hooker, and Bruce J Peterson. 1999. A simple and precise method for measuring ammonium in marine and freshwater ecosystems. Canadian Journal of Fisheries and Aquatic Sciences. 56(10): 1801-1808. https://doi.org/10.1139/f99-128 Obermüller BE, Morley SA, Barnes DKA, Peck LS (2010) Seasonal physiology and ecology of Antarctic marine benthic predators and scavengers. Mar Ecol Prog Ser 415:109-126 https://doi.org/10.3354/meps08735 Peck, L.S. ; Conway, L.Z.. 2000 The myth of metabolic cold adaptation: oxygen consumption in stenothermal Antarctic bivalves. In: Harper, E.M.; Taylor, J.D.; Crame, J.A. , (eds.) The Evolutionary Biology of the Bivalvia. London, Geological Society of London, 441-450. (Geological Society, London, Special Publications, 177, 177). https://doi.org/10.1144/gsl.sp.2000.177.01.29 |
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| Quality: | Ammonia assays were calibrated by spiking seawater with known amounts of ammonium chloride. All samples and standards were read in a TD700 fluorometer. IDs are consistent between faecal_egestion.csv and total_gut_contents.csv. The same 15 individuals used for faecal measurements each month were also used for monthly measurements in seasonal_metabolism.csv, but IDs were not matched to measurements so have not been provided. The 30 individuals sampled in buoyant_weight.csv, of which data is provided for 12, are distinct from the samples used in the other data files. |
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| Lineage/Methodology: | From February 2020 to February 2021 inclusive, monthly collections of 15 individuals each of C. georgiana and H. steineni were made by SCUBA at approximately 15 m depth in Ryder Bay. Individuals were collected haphazardly, avoiding clustering, rather than along fixed transects. Most collections were made in South Cove however, in July and September 2020, thin sea ice prevented access to this site, and sampling was conducted at Hangar Cove instead. Because C. georgiana was absent from Hangar Cove, only H. steineni was collected during these months. 30 additional H. steineni individuals were collected in February 2021 for the purpose of field growth rate determination. Faecal egestion: Upon collection, all sea cucumbers were immediately transported to filtered, flow-through aquarium facilities and stored in individual 2.5 L containers. Faecal pellets were readily distinguishable and were collected using a pipette every 24 h until individuals ceased producing faeces. Daily individual faeces were transferred to 50 mL Falcon tubes and stored at 4 °C until analysis. Faeces were rinsed three times in distilled water by centrifugation to remove residual seawater before being transferred to individual pre-ashed, pre-weighed aluminium containers. Samples were dried at 60 °C to constant mass before being ashed at 460 °C for 12 h, allowing dry mass (DM) and ash-free dry mass (AFDM) to be determined. DM was only measured for faeces-producing months (November - March). A cumulative calculation of total gut content across the repeated measurement time series is also provided. Seasonal metabolism: 72 hours after the sea cucumbers were collected, (the maximum observed time for C. georgiania to cease producing faeces), individual sea cucumbers were transferred into individual respiration chambers placed within a common flow-through aquarium to maintain ambient temperature. Chamber volumes (230-480 mL) were selected following preliminary trials to ensure oxygen concentrations declined by less than 25% over a 12 h incubation. Seasonal differences in metabolism (oxygen consumption, ammonia excretion and O:N ratios) were assessed for C. georgiana. Metabolic measurements were made for C. georgiana every other month during the February 2020-21 collection period (starting February 2020), using the same 15 individuals collected for faecal egestion measurements. Measurements were made with sea cucumbers held within respiration chambers. Routine metabolic rates were measured using closed respirometry. Sea cucumbers were first acclimated in respiration chambers for 12 h with the chambers open and covered with 5 mm mesh to permit water exchange while preventing animals from escaping, allowing metabolic rates to return to routine levels (Peck and Conway, 2000). Chambers were then refreshed with seawater, any air bubbles removed, and sealed for a 12 h incubation. Fifteen chambers containing sea cucumbers and two control chambers containing only seawater were used to account for background microbial respiration. Oxygen concentration was measured at the start and end of the incubation (mean of three readings at each time point). Before each measurement, chambers were gently inverted three times to homogenise the water column. Oxygen concentrations were measured using a Fibox-3 oxygen system (PreSens GmbH; SP-PSt3-NAUspots & OxyView PST3-V5.31 b software) with optical sensor spots, and temperature was recorded throughout the incubation to correct oxygen concentrations for temperature variation. Oxygen spots within each chamber were individually calibrated using the atmospheric pressure (QFF), and both 100% and 0% oxygen saturation; achieved using vigorous aeration and 2.5% w/v sodium dithionite, respectively. To measure holothurian ammonia excretion, water samples were taken from each respiration (and control) chamber at the end of the incubation period. Sea cucumber volume was then determined by water displacement and subtracted from the chamber volume to calculate the seawater volume within each respiration chamber. Water samples were then assayed with ophthalaldehyde (OPA) and fluorometry, using a modified version of the Holmes et al. (1999) method as described by Obermuller et al. (2010). The assay was calibrated by spiking seawater with known amounts of ammonium chloride. Ammonia excretion is expressed relative to the AFDM of each individual as umol NH3 h-1 g-1. Oxygen:Nitrogen (O:N) ratios were measured to provide information about which metabolic substrates were being catabolised by C. georgiana and how these might change seasonally. O:N ratios were calculated using the equation (2 x (O2/NH3)), where O2 and NH3 are provided in umol per hour per gram. The result is multiplied by 2 to account for there being 2 oxygen molecules for each nitrogen. Growth: Seasonal changes in biomass were investigated in H. steineni (but not C. georgiana, due to the availability of specimens). 30 additional H. steineni individuals, representing a range in body sizes, were collected in February 2021 from South Cove for the purpose of field growth rate determination. Upon return to the aquarium, the sea cucumbers were weighed by buoyant mass and placed in labelled individual cages (0.04 m3 made from 1 cm mesh) with rocks as habitat, before being redeployed to South Cove. The sea cucumbers were retrieved using SCUBA in June 2021, October 2021 and February 2022 and at each timepoint they were reweighed using buoyant mass before being returned to South Cove. Buoyant masses were conducted by suspending each individual on a scale in ambient sea water and recording weights on a Sartorius (+/-0.001g) LA3200D balance. Of the 30 sample individuals, data is available for 12, due to some individuals escaping the cages. |
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REFERENCE MATERIALS:
- https://doi.org/10.1139/f99-128
- https://doi.org/10.1144/gsl.sp.2000.177.01.29
- https://doi.org/10.3354/meps
- https://nora.nerc.ac.uk/id/eprint/21193
SOFTWARE PACKAGES:
Extent
| Temporal Coverage: | |
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| Start Date | 2020-02-01 |
| End Date | 2022-02-01 |
| Spatial Coverage: | |
| Latitude | |
| Southernmost | -67.56667 |
| Northernmost | -67.56667 |
| Longitude | |
| Westernmost | -68.33333 |
| Easternmost | -68.33333 |
| Altitude | |
| Min Altitude | N/A |
| Max Altitude | N/A |
| Depth | |
| Min Depth | N/A |
| Max Depth | 15m |
| Location: | |
| Location | Antarctica |
| Detailed Location | Ryder Bay |
Instrumentation
| Data Collection: | R studio (V. 4.4.1; R Core Team 2025) used for data processing. All research was conducted from the Bonner Laboratory at Rothera Research Station. |
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Storage
| Data Storage: | 4x .csv files, 182 KB. |
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