Owl Pellet Biomagnification

Activity Summary
This activity adds depth to the classic owl pellet dissection activity. Students will dissect owl pellets and use a skull and bone key to identify prey species and numbers. Students will then be given levels of DDT that are contained in each prey species as well as a threshold amount of DDT that an owl can consume before her eggs will be unviable. Based on the bones found in
their own owl pellets, students will determine whether their owl will be able to produce viable offspring. This activity shows students that even small amounts of contaminants biomagnify as they move up the food chain and exert their harshest effects on organisms at the top of the food chain (like owls and humans!).

Grade Levels
9-12

Learning Objectives
1. Define biomagnifications
2. Explain the implications of biomagnifications for ecosystems
3. List several consequences of biomagnification for humans
4. Describe how human activities affect non-target organisms

Lesson Materials (view or download)
PowerPoint
Lesson Plan

Keywords
DDT, food chain, food web, human impact, pesticides, pollution

Last updated: 3/3/2015