IAB Research Project Description
Food Web Dynamics in Arctic Streams
Oil and gas activities in the Arctic pose a probable threat to aquatic resources by altering physical and chemical characteristics of arctic streams. Small lower-order streams are potentially the most susceptible to impacts and the most likely to demonstrate the first signs of change. These small stream systems are thought to provide critical habitat for many fish species.
To evaluate potential impacts from oil and gas activities, land managers must first understand the ecological processes in these systems. This knowledge gap will be partially addressed by investigating food web dynamics and energy flow in streams and between streams and their riparian habitats in Arctic Alaska.
Petroleum exploration and development in the Alaskan Arctic has increased in magnitude over the last several years. These activities have the potential to directly and indirectly impact aquatic ecosystems, particularly as permanent infrastructure associated with development is established. Currently there is rapid progress being made towards establishing the first oil development pads on federal lands in the Arctic. More specifically, this planned development is in the National Petroleum Reserve - Alaska (NPR-A) in a location referred to as the Alpine Satellites Development Area. This geographical region includes numerous stream and lake complexes that provide important habitat to many Arctic fish species.
Summer is a critical time for Arctic fish to find quality feeding habitat. Food is plentiful only during this time period and many fish will migrate from overwintering areas to habitat that is more productive for feeding (Craig 1989), often traveling extensive distances (Morris 2003). In general, waters in the Arctic have relatively low productivity and many of the main river channels are less productive than small tributaries or connected lakes that are often warmer. As a result, it is believed that these small tributary systems provide critical feeding habitat for both adult fish and rearing juveniles. However, little is known about the food resources that are available to fish in these systems and to what extent they are being utilized. Studies in other parts of Alaska have shown that terrestrial invertebrates are important prey items for salmonids (Wipfli 1997) and that riparian plant cover greatly affects food abundance for fishes (Allan et al. 2003). A more thorough and comprehensive understanding of food web dynamics will be required to effectively monitor Arctic streams relative to land-use and climate change. Benefits of this work will include contributing to new scientific knowledge and improving the effectiveness of management and monitoring on public lands.
1) Identify key prey types and their sources in Arctic stream food webs.
2) Measure prey utilization by fishes in selected aquatic habitats.
1 Sep 2009 – 30 Sep 2013
IAB Proposal #2010-021
IAB Project #190
302A Irving I
University of Alaska Fairbanks
Fairbanks, AK 99775-7000