Horizontal and vertical dynamics of zooplankton and larval fish communities during mid-summer in Disko Bay, West Greenland

• Published in: Journal of Plankton Research
• Main Authors: Munk, Peter, Nielsen, Torkel Gissel, Hansen, Benni Winding
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2015
• Subjects: ORIGINAL ARTICLES; Arctic; Disko Bank; Greenland; Boreogadus saida; Disko Bay; Mesozooplankton; polar cod; Zooplankton; Copepods
• Online Access: https://orbit.dtu.dk/en/publications/5ccc9763-0b90-417c-a1b4-58e647860861; https://doi.org/10.1093/plankt/fbv034

Disko Bay is a highly productive inlet at the border between high- and low-arctic sectors of west Greenland. The physical/chemical conditions in the bay have changed during recent decades, specifically during an inflow event in 1996–1997 that led to increased deep-water temperatures. To further understand the consequences of physical changes to the plankton community in the bay, we examine findings from a field study on mesozooplankton and fish larvae in the areas of Disko Bay and Disko Bank carried out in 1997. We sampled 31 stations over 5 days along four transects and assessed horizontal and vertical distribution patterns, community composition and plankton trophodynamics. Plankton abundance was enhanced near-coast and across the pycnocline, and communities differed between regions. Polar cod (Boreogadus saida) and the sandeel (Ammodytes sp.) were among the abundant fish larvae. Productivity/growth estimates of key species of copepods and fish larvae showed no apparent relationship to food availability; they reached weight specific values of ∼6% day−1 for copepods and ∼14% day−1 for fish larvae. Overall, we found a rich and dynamic plankton community, strongly influenced by the complex hydrography of the area. Thus, changes in physical characteristics of the bay could threaten the resilience of its ecosystem.