We assessed the influence of coral 'bleaching on the regenerative potential of corals in a senes of field expenments with artificial lesions on colony surfaces These lesions were made d u n n g a mass bleaching event in 1990 on normally coloured and bleached colonies of 3 species A4ontastrea annulans, the main reef-building coral in the Caribbean P o r~t e s astreo~des, a relatively conmon and opportunistic coral, and M e a n d r~n a meandntes, a species common on the deeper reef slope Regeneration charactenshcs studied included rate of tissue growth, recovery of lesion area and restoration of hssue colour Tissue regenerahon rates were lower in all species when companng bleached with unbleached colonies, although there were species-specific differences Long-tern~ exposure to increased temperature probably affects regeneration as bleached colonies of P astreo~des in the thermal effluent of a power plant regenerated as rapidly as normal colonies situated upcurrent and downcurrent of the power plant Colour recovery of bleached colonies was closely associated with seawater temperature When ambient seawater temperature started to decrease (<3OoC), colonies began to regain thelr normal colour Colour restoration was slowest in M a n n u l a r~s Normal colour of coral colonies in the power plant effluent returned at the same t~rne, but at temperatures 2°C hlgher than elsewhere on the reef Mortality on bleached colonies of M annulans and P astreo~des was hlgher than on normal colonies 131 d after the start of the regeneration expenments Large parts of the colony died when the tissue was already regalning its normal colour and lesion regeneration was almost completed Mortality was most severe for colonies In the effluent We recorded the sensitivity of coral species to bleaching in surveys over the reef downcurrent and upcurrent of the power plant These showed that community structure and colony condit~on on the shallow terrace downcurrent differed noticeably from the upcurrent site Downcurrent, specles diversity was lower malnly because of high densit~es of Pontes astreo~des and D~plona stngosa Bleaching was also more prominent downcurrent The decreased regeneration rates and increased mortality of bleached colonies (in Montastrea annular~s in 30 % of the colonies), dunng and subsequent to bleaching clearly Indicate the increased vulnerability of coral reefs dunng penods of thermal stress Coral reef management should consider limiting activities resulting in small lesions under penods of Increased environmental stress