Adult mosquito flight activity was monitored at a coastal marshland site in Chambers County, TX, before, during, and after a total eclipse of the moon on August 16, 1989. A vehicle-mounted mobile interceptor trap and a stationary, dry ice-baited CDC miniature light trap were used in this monitoring effort. Aedes sollicitans, Anopheles crucians, Culex salinarius, and Psorophora columbiae were mosquito species most abundantly represented in collections made by both traps during the 12-h study period. The numbers of each of these species collected by the vehicle-mounted trap decreased during the lunar eclipse and increased when the full moon was exposed. Collections of these same species by the light trap increased during the lunar eclipse and decreased when the full moon was exposed.