Seawater carbonate chemistry and metabolic rate, ventilation rate and critical oxygen partial pressure of Dosidicus gigas and Doryteuthis pealeii

DOI

Ocean acidification is hypothesized to limit the performance of squid owing to their exceptional oxygen demand and pH sensitivity of blood–oxygen binding, which may reduce oxygen supply in acidified waters. The critical oxygen partial pressure (Pcrit), the PO2 below which oxygen supply cannot match basal demand, is a commonly reported index of hypoxia tolerance. Any CO2-induced reduction in oxygen supply should be apparent as an increase in Pcrit. In this study, we assessed the effects of CO2 (46–143 Pa; 455–1410 μatm) on the metabolic rate and Pcrit of two squid species - Dosidicus gigas and Doryteuthis pealeii – through manipulative experiments. We also developed a model, with inputs for hemocyanin pH sensitivity, blood PCO2 and buffering capacity, that simulates blood oxygen supply under varying seawater CO2 partial pressures. We compare model outputs with measured Pcrit in squid. Using blood–O2 parameters from the literature for model inputs, we estimated that, in the absence of blood acid–base regulation, an increase in seawater PCO2 to 100 Pa (1000 μatm) would result in a maximum drop in arterial hemocyanin–O2 saturation by 1.6% at normoxia and a Pcrit increase of 0.5 kPa. Our live-animal experiments support this supposition, as CO2 had no effect on measured metabolic rate or Pcrit in either squid species.

In order to allow full comparability with other ocean acidification data sets, the R package seacarb (Gattuso et al, 2019) was used to compute a complete and consistent set of carbonate system variables, as described by Nisumaa et al. (2010). In this dataset the original values were archived in addition with the recalculated parameters (see related PI). The date of carbonate chemistry calculation by seacarb is 2019-11-20.

Supplement to: Birk, Matthew A; McLean, Erin L; Seibel, Brad A (2018): Ocean acidification does not limit squid metabolism via blood oxygen supply. Journal of Experimental Biology, 221(19), jeb187443

Identifier
DOI https://doi.org/10.1594/PANGAEA.909481
Related Identifier https://doi.org/10.1242/jeb.187443
Related Identifier https://CRAN.R-project.org/package=seacarb
Metadata Access https://ws.pangaea.de/oai/provider?verb=GetRecord&metadataPrefix=datacite4&identifier=oai:pangaea.de:doi:10.1594/PANGAEA.909481
Provenance
Creator Birk, Matthew A ORCID logo; McLean, Erin L ORCID logo; Seibel, Brad A ORCID logo
Publisher PANGAEA
Contributor Yang, Yan
Publication Year 2018
Rights Creative Commons Attribution 4.0 International; https://creativecommons.org/licenses/by/4.0/
OpenAccess true
Representation
Resource Type Supplementary Dataset; Dataset
Format text/tab-separated-values
Size 2908 data points
Discipline Earth System Research