Fri, October 14, 2016 11:00 AM - 12:00 PM AQUATIC ECOSYSTEMS RESEARCH LABORATORY (AERL). Speaker: André Frainer, Post-doctoral researcher, Norwegian College of Fishery Science, University of Tromsø
Background: Recent studies indicate that the composition of fish communities is changing in the Arctic due to climate warming. It is less clear if the functional composition of these communities is also changing, and how that could affect ecosystem functioning.
Methods: I assessed changes in the functional composition of fish communities across space and time using data from 2004 to 2012 covering the entire Barents sea, totalizing nearly 4000 sampling stations. The 54 fish species found were characterized by a set of 20 different functional traits that reflect different aspects of fish biology and ecology, including: information on habitat and diet preferences, body size, fecundity, and foodweb-derived characteristics of each species, among others.
Results: Across the Barents sea, fish functional identity ranged from being more pelagic and piscivorous, and with more foodweb connections to prey and predators (boreal-like) to more benthivorous, smaller, and with fewer foodweb connections (Arctic-like). Random forest analyses indicate that temperature is driving changes in functional composition of these communities, with the formerly widespread Arctic-like communities being reduced to fewer areas in the northeast.
Conclusions: A change in community composition along with changes in its functional composition is already affecting how Arctic ecosystems function, with large implication for its ecosystem properties and for fisheries as well, as the current and future distribution of fish species carrying important traits (e.g., large-bodied, pelagic fish) is rapidly changing northwards.
André Frainer is a postdoctoral researcher at UiT The Arctic University of Norway in Tromsø, Norway. He received his PhD from Umeå University in 2013 in Sweden. His main line of research focuses on investigating how biodiversity affects ecosystem functioning in marine and freshwater ecosystems.
Location: AERL 120
IOF Seminars: Invited speakers present the latest research in a wide range of disciplines related to freshwater systems, the oceans and fisheries. These seminars draw a diverse audience, leading to thought-provoking discussions and a sharing of new ideas and perspectives.