The contribution of ice algae to the winter energy budget of juvenile Antarctic krill in years with contrasting sea ice conditions

Abstract Krill overwintering strategies vary with ontogeny and year; understanding this variability is essential to predicting how the species will respond to climate change in the future. Overwintering studies have focused on larval and adult krill, but we know little about how juvenile krill overw...

Full description

Bibliographic Details
Published in:ICES Journal of Marine Science
Main Authors: Bernard, Kim S, Gunther, Lacey A, Mahaffey, Sean H, Qualls, Katelyn M, Sugla, Monisha, Saenz, Benjamin T, Cossio, Anthony M, Walsh, Jennifer, Reiss, Christian S
Other Authors: Fields, David, G. Unger Vetlesen Foundation
Format: Article in Journal/Newspaper
Language:English
Published: Oxford University Press (OUP) 2018
Subjects:
Antarc*
Antarctic
Antarctic Krill
Antarctic Peninsula
Bransfield Strait
ice algae
Sea ice
Online Access:http://dx.doi.org/10.1093/icesjms/fsy145
http://academic.oup.com/icesjms/article-pdf/76/1/206/31238323/fsy145.pdf
Description
Summary:Abstract Krill overwintering strategies vary with ontogeny and year; understanding this variability is essential to predicting how the species will respond to climate change in the future. Overwintering studies have focused on larval and adult krill, but we know little about how juvenile krill overwinter. The late winter diet of juvenile krill is important because it will determine their growth and development rates and consequently their reproductive potential the following spring. A diet rich in ice algae would promote growth and reproductive development. The Bransfield Strait (northern Antarctic Peninsula, AP) is an important overwintering ground for krill; it has been proposed this region offers a food-rich winter environment. We examined the contribution of ice algae to the energy budget of overwintering juvenile krill during 2 years with contrasting sea ice conditions. Grazing on ice algae contributed ∼146% to their winter energy budget in 2015, even though ice concentrations were ≤50% and consisted of newly formed pancake ice. However, when sea ice advanced late in the Bransfield Strait (2016), ice algae contributed significantly less (∼16%) to the winter energy budget of juvenile krill. Delayed sea ice advance may negatively affect growth and reproductive development of overwintering juvenile krill.

Similar Items