Research Overview
During the summers of 2013 and 2014, I conducted a large-scale island experiment with carabid beetles (Coleoptera: Carabidae) on the islands of Lac la Ronge, northern Saskatchewan, Canada. As part of my master's thesis at the University of Alberta under Dr. John Spence and Dr. Scott Nielsen, I tested how spatial features like island area and isolation influence the distribution and assemblage structure of carabids on these islands. We sampled five mainland sites and 30 islands spanning an area (0.2 – 980.7 ha) and isolation (0.1 – 10.7 km from mainland) gradient. We found that island size was an important factor influencing assemblages and diversity, but in general isolation was not. Carabid assemblages on small islands (< 1 ha) distinctly differed from their nearest mainland counterparts, and had fewer species than larger islands. Life-history traits like body size and wing length (proxy for dispersal ability) appear to influence these patterns. Large-bodied, flightless species are underrepresented on small islands, possibly owing to greater resource demands of large body size and less-frequent colonization because large-bodied species also tend to be flightless.
As is often the case in science, the initial research has raised a number of interesting questions and hypotheses as outlined below:
Experimental introductions - Carabus taedatus is found on most large islands and nearest mainland but is largely absent from the 14 smallest islands (0.2 - 7.5 ha) that I studied. Experimental introductions of C. taedatus to small islands could help determine whether its absence is related to limited dispersal (flightless) and/or unsuitable habitat that prevents this species from establishing on small islands.
Experimental introductions - Carabus taedatus is found on most large islands and nearest mainland but is largely absent from the 14 smallest islands (0.2 - 7.5 ha) that I studied. Experimental introductions of C. taedatus to small islands could help determine whether its absence is related to limited dispersal (flightless) and/or unsuitable habitat that prevents this species from establishing on small islands.
Study Site
Lac la Ronge is located in north-central Saskatchewan, Canada (55°06’ N, 105°01’ W) and is the fifth largest lake in the province (1,413 square kms). The 1,305 islands of Lac La Ronge were formed during the expansion/retreat of the Laurentide ice sheet and provide a range of island sizes (< 0.1 - 980.7 ha) and isolation suitable for island biogeographical questions. The beginning of the Canadian Shield intersects the lake and most of the islands are found in the central to northern reaches. The scouring of the retreating ice sheet created islands that are long and similar in shape, running south-west to north-east.
Some of the islands have summer cabins but owners are not permitted to modify the environment beyond their plots. Consequently, all of the islands are heavily forested and have no undergone significant human alteration.
About me: Aaron Bell
I am currently a M. Sc. student at the University of Alberta, in the first year of my program. I am co-supervised by Dr. Scott Nielsen and Dr. John Spence in the Department of Renewable Resources. I was fortunate to grow up in La Ronge and have spent countless hours on the lake and at my cabin. In my undergrad, I became especially fixated with islands and biodiversity and naturally this led to an interest in studying the islands in my own backyard.
In my free time, I enjoy hockey, playing music, and reading fiction. If you have any questions or comments, please contact me at [email protected]
I am currently a M. Sc. student at the University of Alberta, in the first year of my program. I am co-supervised by Dr. Scott Nielsen and Dr. John Spence in the Department of Renewable Resources. I was fortunate to grow up in La Ronge and have spent countless hours on the lake and at my cabin. In my undergrad, I became especially fixated with islands and biodiversity and naturally this led to an interest in studying the islands in my own backyard.
In my free time, I enjoy hockey, playing music, and reading fiction. If you have any questions or comments, please contact me at [email protected]
Disclaimer
This website was created as part a class project for RenR 690 at the University of Alberta. Any results discussed are preliminary and may be based on modified data sets. Please contact the author for more information.
This website was created as part a class project for RenR 690 at the University of Alberta. Any results discussed are preliminary and may be based on modified data sets. Please contact the author for more information.