Long-term monitoring of one of the most restricted insect populations in the United States, Megalagrion xanthomelas (Sélys-Longchamps), at Tripler Army Medical Center, Oahu, Hawaii (Zygoptera: Coenagrionidae)

Long-term monitoring of a remnant population of M. xanthomelas, located at Triplet Army Medical Center (TAMC) began in May 1997 and continued to Febr. 2000 for the mitigation ponds and June 2000 for the TAMC stream. This sp. has been reduced to little more than 100 m of stream habitat on Oahu at the TAMC. Threats to M. xanthomelas include alien fish spp., stream dewatering, and habitat alteration. The TAMC stream now requires augmented water flow because construction of a facility up gradient of the TAMC stream disrupted the normal hydrology of the small stream. The Oahu race of M. xanthomelas will soon become extinct if the stream were allowed to become dry, as nearly happened in June 1997. The most cost-effective way to ensure the survival of this sp. on Oahu would be to continue some mitigation water flows to the TAMC stream. The next step would be the establishment of another wild population to a stream lacking alien fish spp. It is highly recommended that a cooperative association of biologists from the Bishop Museum, University of Hawaii, U.S. Fish and Wildlife Service, and U.S. Army environmental staff continue to monitor the population of M. xanthomelas, arguably the rarest insect population in the United States,