Logo image
Back
Thermal tolerance and metabolic responses of two damselfish species from a hyperthermic rockpool nursery in Dry Tortugas National Park, USA
Journal article   Peer reviewed

Thermal tolerance and metabolic responses of two damselfish species from a hyperthermic rockpool nursery in Dry Tortugas National Park, USA

Theresa F. Dabruzzi, Ana G. Jimenez, Justin E. Speaks, Sarah R. Stoler, Melanie A. Sutton, Christopher M. Pomory and Wayne A. Bennett
Caribbean Journal of Science, Vol.47, pp.213-219
47
2013
DOI: https://doi.org/10.18475/cjos.v47i3.a10
Web of Science ID: WOS:000209715500009

Metrics

124 Record Views
1 Times Cited - Web of Science

Abstract

Beachrock formations on Loggerhead Key in Dry Tortugas National Park, USA are an important nursery for many juvenile reef fishes. Wide variations in temperature are common in these areas and can markedly influence fish metabolism and thermal tolerance. We determined routine resting metabolic rate and temperature quotient (Q₁₀) at 24 and 32°C. Thermal tolerance (measured as critical thermal maximum, CTmax) was also measured for sergeant major (Abudefduf saxitilis) and cocoa damselfish (Stegastes variabilis) acclimatized to beachrock nursery temperatures. Sergeant majors occupied shallow rockpool margins that experience rapid, extreme temperature changes. These fish exhibited relatively low metabolic rates, reduced Q₁₀ values (2.40), and relatively high levels of temperature tolerance (CTmax = 40.0°C). Cocoa damselfish selected deeper, more thermally stable rockpool areas. These fish had higher metabolic rates, were more sensitive to temperature increase (Q₁₀ = 2.84), and were less tolerant of high temperatures (CTmax = 38.6°C) than sergeant majors. Metabolic and temperature tolerance adaptations of juvenile sergeant majors and cocoa damselfish allow these fishes to exploit a variety of microhabitats found in beachrock areas on Loggerhead Key.

Details

Logo image