Sarah Apsens
University of WA
Researched age-0 Northern Rock Sole density and length distributions in two areas near the Aleutian Islands.

The sediment samples and flatfish data used for this project were collected on cruises in 2003 on the Bering Sea shelf, and in 2008 along the North side of the Alaska Peninsula. The sediment was analyzed using a series of sieves to determine how much of each sample was sand (2.00mm to 0.063mm grain size), gravel (>2.00mm) and mud (less than 63mm). Next, each sediment sample was assigned a specific sediment type using the Folk (1980) classification scheme. Under this classification scheme each sample was given a label based on its grain size composition, such as S (sand), Sm (sandy mud), [g]mS (sandy mud with a trace of gravel) etc. Though this gave some interesting information the classification scheme turned out to be difficult to use for the type of analysis that was needed for this project, and after looking more closely at the nature of the samples the decision was made to use percent sand for all further analysis.

Next, the data on percent sand was used to make an interpolation over the study area using ArcGIS. Density and lengths of age-0 Northern Rock Sole were plotted over the study area and a statistics program was used to find any significant trends. For the 2008 study area, which covered a section of the Bering Sea along the North side of the Alaska Peninsula, I was not able to find any statistically significant correlations between age-0 Northern Rock Sole density and sediment type. However, there were some correlations between length and sediment type. This was really interesting because it conflicted with the expected results and suggests that there may be some other factor like depth or current patterns that are the determining factors in age-0 Northern Rock Sole density distributions in this area.