The hunters glide silently through the warm Pacific waters of Kwajalein Atoll and spear fish that can provide a key to the health of the local environment.
The hunters are Dr. Lisa Ruth, aquatic biologist, and Ellyce Bushong and Jennifer Cearfoss, environmental engineers, all from the U.S. Army Public Health Command Water Resources Program at Aberdeen Proving Ground, Md.
Their goal is to determine if consumption of Kwajalein Atoll fish poses an unacceptable health risk to local fishermen.
The U.S. Army Kwajalein Atoll, or USAKA, is a coral reef formation located in the Republic of the Marshall Islands more than 2,000 miles southwest of Hawaii. USAKA consists of more than 100 islets, 11 of which currently serve as a test and evaluation range for ballistic missiles. The USAPHC has conducted surveys and provided environmental consultative services to USAKA for more than 25 years.
In this most recent study, several hundred fish were collected during a multi-week field investigation to assess the accumulation of potential contaminants that might affect the local population.
"A type of spear called a Hawaiian sling was used to collect the target fish species, which ranged from extremely small angelfish to much larger grouper and parrotfish," explained Ruth, lead project officer.
"We worked in collaboration with a U.S. Fish and Wildlife Service diver not only to collect the fish, but to conduct biological surveys of the coral reef communities at each islet. This enabled us to deploy two separate teams of divers each time we entered the water," said Cearfoss, dive safety officer.
"We all agree having the opportunity to conduct field work on a project like this is a pleasant change from our more traditional engineering projects that often take place in less scenic locations," said Bushong.
But there were still rules to be followed in this underwater office.
"Guidelines from the Institutional Animal Care and Use Committee directed the way we treat the fish. We worked with Lt. Col. Dawn Fitzhugh, USAPHC veterinarian, to develop humane methods," said Ruth.
"Our divers collected tissue samples from 60 different fish species to determine if the fish could be safely consumed by local Marshallese people," explained William Fifty, USAPHC water resources program manager.
"Contamination in the harbor area from industrial processes, such as sandblasting ships and the use of pesticides, have raised concerns about the consumption of fish from the local area," Ruth added.
"Previous studies indicated that the excellent marine water quality is impaired only in the immediate vicinity of industrial activities near the harbor and local landfill," said Fifty.
"This project is a prime example of how the three pillars of public health--humans, animals and environment--interact and are dependent upon each other," explained Lt. Col. William Bettin, director of the Environmental Health Engineering Portfolio at the USAPHC. "Decades of industrial activities have affected the marine environment, including the fish and mollusks consumed by human and animal populations. This project demonstrates the importance of public health."
This study also brought together many of the important players in the federal environmental community.
"We work with the Environmental Protection Agency, the U.S. Fish and Wildlife Service, the U.S. Army Corps of Engineers, and the National Oceanic and Atmospheric Administration, as well as the Republic of the Marshall Islands, to ensure the best possible science is used to protect people and the marine environment," explained Cearfoss.
"Ultimately, as members of the scientific dive team, we play an important role in public health," said Ruth. "Of course we enjoy diving and our project locations, but the most rewarding part is knowing that our work ensures the safety and health of the local population."
Once fish and other samples have been collected, they are sent to the USAPHC laboratory and additional contract laboratories for analysis.
"Although the final evaluation will take some time to complete, it will include laboratory data, biological surveys of the study area, and a human health risk assessment," said Ruth. "The final report will also make recommendations for future actions, if they are needed, to ensure safety of the Marshallese people and others who live and work in this paradise."