In order to save the herd, federal wildlife managers say they may begin fencing in healthy Key deer battling a grisly outbreak of New World screwworm.
Crews have begun building a six-foot high enclosure covering several acres of pine rockland in the National Key Deer Refuge at the north end of Big Pine Key, U.S. Fish and Wildlife officials said. If the population of the herd — the planet’s last — drops below what it needs to survive, vets will corral healthy deer inside the pen erected with black plastic deer fencing.
FWS officials are now working with Texas A & M University, where much of the Key deer research is based, to determine what that number should be.
“We are focusing on Big Pine Key and No Name Key due to primary herds being located on these two keys as well as it being in the impact area,” spokesman Kevin Lowry said in a text Monday.
121The number of Key deer killed by screwworm infections as of Sunday.
When the diminutive deer — a cousin of the mainland white tail deer that migrated across a land bridge about 13,000 years ago — were added to the endangered species list in the mid 1950s, the number had dwindled to about two dozen. The herd now stands at about 1,000, wildlife officials say. Since August, screwworm infestations have killed 121.
Officials took the unprecedented step as they ramp up efforts to save the deer after mostly males, in the midst of the mating season, started turning up in carports and under porches with festering wounds on their heads and shoulders. In the last two weeks, volunteers and refuge biologists have doled out 787 doses of doramectin, a powerful anti-parasitic commonly used to treat screwworm outbreaks in domestic livestock, to tamer deer in neighborhoods. It’s not clear how many individual deer were treated.
But wild deer that wander more remote areas of the 8,500-acre refuge are proving harder to treat. Vets treated six deer over the last week, using darts to sedate them, then manually removing screwworm larva and applying a 30-day dose of a topical parasitic. A seventh severely infected deer was euthanzied.
Federal entomologists are also releasing millions of sterile male flies in the coming weeks to mate with wild females and stop reproduction of wild screwworms.
For the time being, four large gates on the new pen will remain open, allowing deer to wander in and out, FWS officials said. But if the number of dead deer climbs too high, vets plan on luring a group of deer into the pen and closing the gates. A smaller enclosure will be built on Cudjoe Key to save a separate population if necessary.
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