Case Study: Relation between Yellow Perch Growth and Population Size Structure

In this short case study, we will relate growth back to other population characteristics discussed earlier in the course.   Below are two length-frequency histograms for yellow perch population samples.  Both were collected in early fall with experimental (i.e., multiple mesh) gill nets from two eastern SD lakes.  Break into teams of two or three, and then assess the size structure for these two samples.  Next, answer the questions at the bottom of the page.

1. Which population has fast growth and which has slow growth?

2. Which sample is from a deeper lake with abundant, submergent aquatic vegetation, and which is from a shallower, more windswept lake with very little submergent vegetation?

3. In which population is the perch diet dominated by macroinvertebrates and which by zooplankton?

4. Any guesses on the actual lake names??  J