FORT SILL, Okla., Feb. 9, 2017 -- The most famous bird here, the black-capped vireo, is in the process of being promoted (or demoted, depending on one's point of view).

Currently on the endangered species list, this distinctive songbird has been recommended for delisting by the U.S. Fish & Wildlife Service (USFWS) following a study completed in 2007.

On Sept. 29, 2016, several ranching entities reached a legal settlement with USFWS to completely delist the vireo, three plants and the lesser long-nosed bat, all of which were part of the study. The petition required USFWS to enter the proposed change in the Federal Register, which it did on Dec. 15, 2016.

Omar Bocanegra, supervisory fish and wildlife biologist for USFWS Southwest Region based in Dallas, said public comments will be taken through Feb. 13 regarding the changes. Assuming no evidence is presented to warrant continued listing, the new status will go into effect Dec. 15. The bird will then have no special habitat protections afforded it under the Endangered Species Act.

However, there will be a minimum of five years of post-delisting monitoring (PDM) to make sure that the species' status does not deteriorate. If it does, an emergency re-listing is a possibility.

Bocanegra believes that based on the study, the habitat and parasitic cowbird control necessary to preserve the species will continue on areas that have the largest vireo populations and active monitoring, including Fort Sill, the Wichita Mountains Wildlife Refuge, and Fort Hood, Texas.

"This is a great success story for Fort Sill, the Army and endangered species management," said Chris Deurmyer, Fort Sill's wildlife and fisheries biologist. Fort Sill will continue its existing management to protect the species, and will furnish information to USFWS as part of the five-year PDM.

"We now have a huge amount of life history information and breeding site data from here," said Deurmyer. "We are committed to providing stewardship of resources entrusted to the Army. This information will be used to forge future management decisions since we all want the black-capped vireo to continue its success on Fort Sill."

Although the USFWS estimates there are fewer than 15,000 black-capped vireos nesting in limited ranges in Texas, Oklahoma, and the northern states of Mexico, agency scientists believe the threats to the species have been mitigated.

"It's not the number of individuals in a species," said Bocanegra, "it's the degree of the threat."

For a plant or animal species to be listed as endangered, it must face an immediate threat of extinction, said Bocanegra. A threatened species faces extinction "in the foreseeable future" and would merit a lesser degree of protection.

The impetus behind the move was an earlier petition to downlist from endangered to threatened, filed July 16, 2012 in U. S. District Court for the District of New Mexico by several ranching and farm entities, including the Texas Farm Bureau.

They are represented by Pacific Legal Foundation, whose website states its purpose is to "protect our Constitution, and litigate for limited government, property rights, free enterprise, and a balanced approach to environmental regulations."

One of the firm's success stories, which it lists under "Endangered Species Act Abuse" on its website, is getting the bald eagle removed from the endangered species list.

The petitioners, most of whom are from areas where the vireo does not live or migrate through, asked for a complete delisting based on the information presented in the 2007 study, and USFWS agreed.

"We looked at the best available information, and the trajectory of the overall status continues to move upward," Bocanegra said of the vireo. "We don't think its threats will come back and can be managed."

Part of the optimism is that overall rangeland has increased by 17 percent, and although that in itself doesn't mean it is good vireo habitat, it shows a degree of land use more conducive to potential vireo habitat, according to a USFWS report.

"There was a huge goat population in Texas," said Bocanegra. "It's dropped by 47 percent in a two-year period. Goats eat everything out there, so the habitat is bouncing back."

However, Joe Grzybowski, the ornithologist who is contracted by Fort Sill to monitor the vireo during breeding season and was involved in the initial population surveys that placed it on the endangered species list, isn't so sure.

"It is still uncertain that vireo numbers can maintain themselves without management," he said, "and (the vireo) is still absent from much of its former northeastern range. Post-delisting monitoring may shed some light."

Grzybowski's initial surveys in 1987 found only five pairs of black-capped vireos on Fort Sill. There are now 600 to 700 nesting pairs on post.

The vireo's nemesis, the native brown-headed cowbird, evolved to follow the millions of bison that once roamed the country, and as such was not able to stay in one place to raise babies. So the females lay eggs in the nests of other birds who then become surrogate parents.

Typically the cowbird eggs hatch first, and the larger chick will push out or kill the rightful occupants. The black-capped vireo's breeding success rate was jeopardized by cowbirds, as they are a favored target. On Fort Sill and the refuge, an active cowbird capture program has helped increase the vireo populations.

"Cowbird parasitism is more severe in eastern Texas and in Oklahoma than in west Texas," said Bocanegra. USFWS has done a study projecting land use changes and potential threats to the vireo for 50 years out. "We're confident if we continue what we're doing now, the populations would be resilient."

Most of the bird's breeding habitat in west Texas is rangeland, said Bocanegra. "We don't see threats to that habitat."

As with nearly all native bird species, the black-capped vireo will continue to be protected under the Migratory Bird Treaty Act which protects most species of birds but does not provide habitat protections afforded under the Endangered Species Act.

Military bases are compelled under the Sikes Act to produce an integrated natural resources management plan to care for resources and recreational opportunities while also maintaining training areas.

"We appreciate what Fort Sill has done to work with us," said Bocanegra. "It doesn't get much better than this as a success story."