Author Posting. © The Author(s), 2019. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in , Zakroff, C., Mooney, T.A. & Berumen, M.L. Dose-dependence and small-scale variability in responses to ocean acidification during squid, Doryteuthis pealeii, development. Marine Biology, (2019), 166: 62. doi:10.1007/s00227-019-3510-8.
Coastal squids lay their eggs on the benthos, leaving them to develop in a dynamic system that is undergoing rapid acidification due to human influence. Prior studies have broadly investigated the impacts of ocean acidification on embryonic squid, but have not addressed the thresholds at which these responses occur or their potential variability. We raised squid, Doryteuthis pealeii (captured in Vineyard Sound, Massachusetts, USA: 41° 23.370N 70° 46.418´W), eggs in three trials across the breeding season (May - September, 2013) in a total of six chronic pCO2 exposures (400, 550, 850, 1300, 1900, and 2200 ppm). Hatchlings were counted and subsampled for mantle length, yolk volume, hatching time, hatching success, and statolith morphology. New methods for analysis of statolith shape, rugosity, and surface degradation were developed and are presented (with code). Responses to acidification (e.g., reduced mantle lengths, delayed hatching, and smaller, more degraded statoliths) were evident at ~ 1300 ppm CO2. However, patterns of physiological response and energy management, based on comparisons of yolk consumption and growth, varied among trials. Interactions between pCO2 and hatching day indicated a potential influence of exposure time on responses, while interactions with culture vessel highlighted the substantive natural variability within a clutch of eggs. While this study is consistent with, and expands upon, previous findings of sensitivity of the early life stages to acidification, it also highlights the plasticity and potential for resilience in this population of squid.
This material was based upon work supported by the National Science Foundation Graduate Research Fellowship under Grant No. 1122374 to CZ. This project was funded by National Science Foundation Grant No. 1220034 to TAM.
Woods Hole Open Access Server