Submission Date


Document Type

Paper- Restricted to Campus Access



Faculty Mentor

Cory Straub


Presented during the 24th Annual Summer Fellows Symposium, July 22, 2022 at Ursinus College.

Project Description

Aphids can stunt plant growth and cause economic damage in agroecosystems. Predatory arthropods, including beetles and spiders, consume these agricultural pests. This biological pest control is a valuable ecosystem service.

Some predator species may consume more aphids, and thus function better, when the temperature is warmer, while others function better when it is colder. Such thermal-niche diversity would ensure that the process of biological pest control remains stable even when temperatures fluctuate. In this study we are characterizing the thermal niches of ground-active predators that consume aphid pests of barley. Each species is exposed to a fixed temperature ranging from 10°C-35°C, increasing in increments of 5°C. Predators are presented with aphids during the experimental period and the number of aphids consumed is recorded. Predator movement, e.g., distance moved and acceleration, is measured using the video tracking software system, Ethovision. We hypothesize that predator movement and aphid consumption will be positively correlated, and that different predator species will function best at different temperatures. The results of this study may be used to inform conservation strategies that benefit biological pest control.


Available to Ursinus community only.