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We evaluated relationships between climatological variables and abundance of larval yellow perch (Perca flavescens) in eastern South Dakota glacial lakes. Age-0 yellow perch were collected using a 0.75 m diameter ichthyoplankton net from May through mid-June at 7 to 10 d intervals. Highest correlation coefficients with larval yellow perch abundance were for April total precipitation (r-0.95–0.99; P=0.09–0.01; three lakes), mean March wind speed (r=-0.98 to −0.99; P=0.02–0.006; two lakes), mean of May average daily temperatures (1-0.78; P=0.12; one lake) and mean May wind speed (r=-0.82; P=0.02; one lake). Given the low number of years in some samples, individual years at times had undue influence on the relationship, resulting in high correlation coefficients. Multiple regression modeling resulted in improved models for only two of the seven lakes (R2=0.90–0.98; P=0.05–0.02). However, March through May weather patterns in some combination were related to larval yellow perch abundance in all seven...

Alewives were collected by nighttime gill netting during summer 1999 from 12 Connecticut lakes that support landlocked populations to determine relationships between population characteristics and physicochemical lake variables. Mean catch-per-unit-effort (CPUE) ranged from 0.2 to 16.4 age-1 and older alewives per net hour. Maximum ages of alewives among lakes ranged from two to five years, and mean back-calculated length-at-age-1, used to index growth rate, ranged from 78 to 146 mm. Mean back-calculated length-at-age-1 was positively correlated with mean relative condition factor (Kn), watershed area:lake surface area ratio, watershed area:lake volume ratio, lake surface area:lake volume ratio, conductivity, total nitrogen, alkalinity, calcium, magnesium, and chlorophyll a, and negatively correlated with retention time, maximum lake depth, mean lake depth, and transparency. Mean Kn ranged from 0.93 to 1.23 and was positively correlated with mean back-calculated length-at-age-1, watershed area:la...

During summer 1999, 5,004 landlocked alewives (Alosa pseudoharengus) were captured from 12 Connecticut lakes using horizontal gill nets with mesh sizes of 9.5, 12.7, 15.9, 19.1, 25.4, and 31.8 mm (bar measure). The most effective mesh size was 12.7-mm, capturing 3,035 alewives. The modal length of alewives caught in each mesh size increased as the mesh size increased from 9.5 to 25.4 mm. No alewives less than 70 mm total length or greater than 245 mm were captured. Modal lengths of selectivity curves estimated indirectly using the Holt model were 85, 114, 143, 172, and 228 mm for the 9.5-, 12.7–15.9-, 19. 1-, and 25.4-mm mesh sizes, respectively. Adding a 22.3-mm mesh and removing the 31.8-mm mesh is suggested to sample landlocked alewives between 100 and 245 mm in Connecticut lakes.