Effect of spring and summer temperatures on amphipod reproduction (Gammarus lacustris)
Principal Investigator: Messmer, David J (1)
Licence Number: 15066
Organization: University of Saskatchewan
Licensed Year(s): 2012
Issued: May 17, 2012
Project Team: Daniel Coulton, Blake Bentzen

Objective(s): To determine how spring and summer temperatures affect the abundance of the amphipod Gammarus lacustris throughout the summer.

Project Description: To determine how spring and summer temperatures affect the abundance of the amphipod Gammarus lacustris throughout the summer. Over the 2 years of the experiment, the research team plans to use amphipods from 4 different sources over several latitudes (Montana-USA, St. Denis-SK, Yellowknife-NT, Inuvik, NT). Using this variety of geographic sources will allow us to assess if different populations adjust their breeding to the stimulus of temperature differently. The research team proposes to collect amphipods from the shore of wetlands using hand-held dip nets. Collection will begin as soon as the wetlands are sufficiently free of ice. Wetlands will be chosen based on their ease of access from the roads. Approximately 500 amphipods will be collected in each year of the study from both the Gwich'in and North Slave regions. Amphipods will be shipped to Saskatoon, and will be raised in enclosures to simulate spring and summer temperatures -2C below average, average, +2C above average and +4C above average. The number of offspring produced over time will be recorded. Of particular interest is relative timing of first offspring production, peak offspring production, and the end of offspring production. These research activities in the NWT are limited to the collection of aquatic invertebrates (amphipods (Gammarus lacustris); also known as side-swimmers, scuds, freshwater shrimp) , which will be sent to Saskatoon for a lab experiment. Because G. lacustris is an abundant and widespread aquatic invertebrate, collection will likely involve only a few hours of work over 1-2 days by 1-2 persons, As such there is little opportunity for community involvement with the field work. However, the educational benefit that will result from this experiment is helping local communities understand the effects of variable climate on the reproduction of an important invertebrate in aquatic food-webs. Any report, publication, or thesis using results of the data collected in the communities will be shared with people in the areas where research was done. Due to the Principal Investigator's residence in Saskatoon, SK, community presentations in Yellowknife or Inuvik are unlikely, but would be considered if the opportunity was available. The fieldwork for this study will be conducted from May 17, 2012 to June 30, 2012.