Mackay Island National Wildlife Refuge
P.O. Box 39
316 Marsh Causeway
Knotts Island, NC 27950

Contact: Mike Hoff 252-429-3100
email: Mike_Hoff@fws.gov


News Release

June 16, 2008

Mackay Island National Wildlife Refuge Fish Kill Appears to Have Been an Isolated Incident

According to Mackay Island National Wildlife Refuge Manager Mike Hoff, the fish kill following last week's record high temperatures appears to be an isolated event. Last Wednesday, refuge employees discovered approximately 400 fish had perished when the temperatures finally returned to normal. The pump used to manage the water levels in the impoundment was turned on three days prior to the onset of the heat to decrease the possibility of such an event. “As water temperatures increase, the amount of dissolved oxygen it will hold decreases. The vast quantity of oxygen-stealing decomposition of plant material on the bottom combined with the increase in temperature provided the unfortunate recipe for the die-off.” Hoff said. “Apparently a pocket of oxygen-depleted water formed in the northwest corner providing a dead zone that fish were not able to escape from,” he added. Several species of game fish seemed to be unaffected by the incident. Refuge staff continue to monitor the area with no evidence of a reoccurring problem.