Temperature:
Pterois volitans is a tropical species, but it nevertheless exhibits a fairly broad thermal tolerance across its native and introduced range. Although juvenile individuals have been collected as far north as Long island, New York, these individuals were almost certainly spawned in warmer waters of the U.S. southeastern coast (Meister et al. 2005).
Thermal tolerance studies by Kimball et al. (2004) reveal an average lethal low temperature for P. volitans of 10.0°C and a low temperature at which feeding ceases of 16.0°C. These findings suggest red lionfish should survive typical winter temperatures on the U.S. east coast as far north as Cape Hatteras, NC, while it remains unknown if animals can overwinter north of this point (Whitfield et al. 2002).
Salinity:
Pterois volitans is a marine species, although it is found in inshore lagoons in its native range. Juvenile individuals have been collected off the northeastern U.S. continental shelf where salinities are typically in the range of 30-33ppt, somewhat lower than salinities in southeastern coastal waters (34-36 ppt) (Whitfield et al. 2002).