A plan initiated by Bexar County to protect nine endangered species while making it easier for developers to comply with the Endangered Species Act has gained federal approval.

The Southern Edwards Plateau Habitat Conservation Plan focuses on two birds, the golden-cheeked warbler and black-capped vireo, and seven cave-dwelling invertebrates.

Under the plan, developers who agree to abide by certain rules and pay fees can be assured their projects will not run afoul of the Endangered Species Act. It creates a system where habitat lost in Bexar County would be offset by new preserves established in a seven-county area. There are also rules meant to minimize harm to sensitive sites.

“We do believe that this plan will increase compliance under the Endangered Species Act,” said Adam Zerrenner, supervisor of the U.S. Fish & Wildlife Service’s Austin field office. “In essence, it balances both the needs of economic development and endangered species protection.”

Fully implementing the plan over 30 years is expected to cost nearly $300 million, the plan states, with funding coming from developer fees, a proposed property tax on new development in north Bexar County and other, smaller sources.

Officials with the county and Fish & Wildflife expect about 57 percent of that money will be used to buy preserve land in Bexar, Comal, Blanco, Kendall, Kerr, Bandera and Medina counties. If the plan is implemented fully, it calls for at least 23,430 new acres of preserve for the golden-cheeked warbler, 6,600 acres for the black-capped vireo and 1,000 acres for the cave species.

However, full implementation would also lead to loss of 9,371 acres of habitat for the golden-cheeked warbler, 2,640 acres for the black-capped vireo and development on 21,086 acres underlain by karst. The karst areas would include 49 openings occupied by cave species. Yet, the plan’s rules for building near cave openings would avoid harming them, it states.

In general, this is how it would work:

Developers who would affect the two bird species’ habitat would pay $8,000 per acre where there would be direct impact. They will have to avoid clearing trees from the property during spring and summer nesting season only and take steps to protect trees on the property from oak wilt, so the trees will survive for habitat purposes.

For cave species, developers will generally have to avoid caves designated “critical habitat” by the Fish & Wildlife Service. For other caves, they will have to work with the county and city to determine if they must stay back up to 750 feet from cave openings.

If allowed to develop close to the caves, they will be assessed fees of $400,000 to build up to 345 feet from the entrance and $40,000 to build between 345 and 750 feet, with the money going toward preserves. They can also provide suitable karst land in lieu of payments.

The plan, approved Dec. 18 by the Fish & Wildlife Service, emerged from the ongoing conflict between development in North Bexar County and endangered species that rely on cave systems and tree cover in the hilly limestone landscape of the Southern Edwards Plateau.

One of the best-known examples of this tension happened in 2012. Construction on a new road underpass at the intersection of Loop 1604 and Texas 151 was halted after discovery of an ultra-rare cave spider. A redesign meant to protect the species added two years and $30 million to the construction work.

Under the current regulatory framework, developers who might encounter endangered birds or invertebrates must seek approval from the Fish & Wildlife Service on a project-by-project basis.

Abiding by the new plan is voluntary. Developers can still op to seek Fish & Wildlife Service approval for each project on its own.

But gaining approval en masse through the plan will significantly cut down on time and expense, said Jean Krejca, president of Zara Environmental, a biological consultant that helped develop the plan.

“Typically, you're looking at months (versus) years and probably an order of magnitude cheaper,” Krejca said in an email.

A plan like this is by no means unique in Central Texas. Austin and Travis County’s habitat conservation plan was the first approved in the U.S., Zerrenner said. The Edwards Aquifer Authority manages a habitat conservation plan, as does Comal County.

This plan began with concerns about Camp Bullis, county public works director Renee Green said. Developers cutting down juniper and other trees in the area around the military installation were pushing golden-cheeked warblers on to the base, which must abide by its own set of federal regulations to protect endangered species. Military officials worried that protecting so many birds would compromise the base’s training missions.

“We undertook this effort for two reasons — one, to protect the military bases, and to protect the endangered species,” Green said.

To write the plan, the county and city jointly received a $1.3 million grant from the state and federal governments in 2009, with an agreement to match it with $446,000 of their own.

The two local governments then spent two years negotiating the details under the advice of two advisory groups meant to represent the interests of biologists, conservationists, developers and landowners.

Proposals met with opposition from some Hill Country landowners who warned about government overreach into private lands. The plan’s final draft repeatedly stresses that participation is voluntary, and the city and county will only purchase conservation easements or land for preserves from willing buyers.

Now that the language is final, the real work of putting it into action begins. Zerrenner compared it to a marriage before and after the vows.

“Making the plan work is often as difficult or more difficult than making the plan,” he said.

The city and county will have to sign an agreement outlining their roles and developing an implementation plan. That will likely come before county commissioners and the City Council in the next six months, Green said.

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