DAO 86:245-251 (2009)  -  doi:10.3354/dao02125

Effects of temperature, season and locality on wasting disease in the keystone predatory sea star Pisaster ochraceus

Amanda E. Bates1,2,* , Brett J. Hilton1,2, Christopher D. G. Harley2

1Bamfield Marine Sciences Centre, 100 Pachena Road, Bamfield, British Columbia VOR 1BO, Canada
2Department of Zoology, University of British Columbia, 6270 University Boulevard, Vancouver, British Columbia V6T 1Z4, Canada

ABSTRACT: This study investigates wasting disease in the northeast Pacific keystone predatory sea star Pisaster ochraceus on the outer west coast of Vancouver Island (British Columbia, Canada). To quantify the effects of temperature, season and locality on the vulnerability of P. ochraceus to wasting disease, we conducted surveys and experiments in early and late summer. To test the prediction that a small increase in temperature would result in heightened infection intensities, we housed sea stars at different temperatures in the laboratory and caged sea stars subtidally at 2 depths. Prevalence and infection intensity were always higher in warm temperature treatments and did not differ between the sexes or with increasing size. Disease effects also varied with season and locality. Specimens held in aquaria displayed significantly higher disease prevalence and infection intensity in June versus August. Furthermore, sea stars from a sheltered inlet showed markedly higher prevalence of the disease in late summer, while wave-exposed sites had consistently low disease prevalence. Seasonal changes in reproductive potential, host condition and/or physiological acclimation, as well as differences in environmental regime among localities, may impact the dynamics of wasting disease. These results demonstrate that small increases in temperature could drive mass mortalities of Pisaster due to wasting disease, with vulnerability possibly reaching a peak in spring and in populations from sheltered localities. This is the most northern report of wasting disease in the class Asteroidea on the west coast of North America.


KEY WORDS: Global warming · Temperature · Wasting disease · Pisaster ochraceus · Echinoderm


Full text in pdf format 
Cite this article as: Bates AE, Hilton BJ, Harley CDG (2009) Effects of temperature, season and locality on wasting disease in the keystone predatory sea star Pisaster ochraceus. Dis Aquat Org 86:245-251

Export citation: Endnote - Reference Manager
Mail this link - Contents Mailing Lists - RSS
- -