EVALUATING REMOTE SITE INCUBATORS TO SUPPORT ARCTIC GRAYLING RESTORATION IN MICHIGAN
The Arctic grayling (Thymallus arcticus) was extirpated from Michigan by 1936, and subsequent efforts to reintroduce the species failed. However, efforts to restore Arctic grayling in Montana have been successful through the use of remote site incubators (RSIs), which allow fish to be reared and stocked at the site of introduction. To support future reintroduction efforts of Arctic grayling, we conducted a study using rainbow trout (Oncorhynchus mykiss) eggs (as surrogates for Arctic grayling) to evaluate RSIs in three Michigan streams. Our objectives were to: (1) compare hatching success between two different RSI designs (19-L vs. 256-L RSIs), and (2) test if the removal of dead eggs from 19-L RSIs affected hatching success. Survival ranged from 40.3% to 42.4% (mean=41.4%) across the three study streams. Mean survival in picked RSIs (45.6%) was not significantly different from unpicked RSIs (44.4%; p>0.1). Survival between 256-L and 19-L RSIs by stream differed from 1.8% to 10.3% (mean=5.3%). Preliminary results suggested that removing dead eggs from RSIs during incubation did not markedly increase hatching success, and both small and large RSI designs can be used successfully in Michigan streams.
Carl R. Ruetz III (Primary Presenter/Author), Grand Valley State University, firstname.lastname@example.org;
Alan Mock (Co-Presenter/Co-Author), Annis Water Resources Institute, Grand Valley State University, email@example.com;
Dan Mays (Co-Presenter/Co-Author), Little River Band Ottawa Indians, firstname.lastname@example.org;
Archie Martell (Co-Presenter/Co-Author), Little River Band Ottawa Indians, ArchieMartell@lrboi-nsn.gov;