Why Do Bark Scorpions Prefer Rock?
Date
2008-04-26
Authors
Pendley, Eryn
Rowe, Ph.D., Matthew
Journal Title
Journal ISSN
Volume Title
Publisher
Sam Houston State University. Elliott T. Bower's Honor College
Abstract
Description
The species genus Centruroides is collectively referred to as bark scorpions. Contrary to their common name, these scorpions are frequently associated with rock outcrops. We hypothesize this substrate choice reflects the thermal preferences of the scorpions. To test this, we compared the body temperatures and substrate choices of two populations of Centruroides vittatus, one inhabiting the Piney Woods of East Texas (with no rock), the other a rocky bajada in the Organ Mountains of New Mexico. Previous laboratory results show bark scorpions prefer very warm substrates (~38 degrees Celsius), perhaps due to sprint-speed advantages of being warm. In the Piney Woods however, scorpions seldom achieved these warmer temperatures - with little rock, abundant leaf litter, and a closed canopy, the homogeneous microhabitats of the Piney woods lose heat quickly after sundown. We used temperature data loggers to determine substrate temperatures in the more heterogeneous habitats in NM. Nighttime field surveys recorded scorpion body temperatures, substrate choice, and substrate temperatures. Preliminary analyses show that, between 8:00pm and midnight, scorpions elevate their body temperatures by choosing rocky substrates that hold heat longer than do trees and shrubs.
Keywords
Animal heat, Body temperature--Measurement, Scorpions, Habitat selection