AWU looking for survey and inventory of endangered birds

Last week the Water and Wastewater Commission voted unanimously to recommend the approval of two 12-month service contracts for the survey and inventory of two endangered bird species. The companies up for contract consideration, Hicks & Company and Baer Engineering & Environmental Consulting, Inc., both in Austin, will be charged with documenting how much of the Austin Water Utility’s Water Quality Protection Lands are occupied by the Golden-Cheeked Warbler and the Black-Capped Vireo.

 

The reason AWU needs to know exactly where these birds are comes down to ecosystems. The wildlands managed under the Water Quality Protection Lands program, an area of over 8400 acres, optimize the quantity and quality of water recharging the Barton Springs segment of the Edwards Aquifer. In order to make sure that those wildlands are producing the most water possible, AWU must increase the amount of savanna and prairie habitat in the wildlands and decrease the area that is transitioning from prairie and savanna to woodland ecosystems.

 

There’s an inverse relationship between canopy cover and yield of water per acre per year. Prairies (grasslands without tree cover) and savannas (grasslands with minimal, scattered tree cover) yield more water than woodlands, with its dense canopy cover of juniper trees. So the more savanna and prairie land in the WQPL, the more water that feeds Barton Springs.

 

The AWU won’t take woodland habitat and push it back to prairie and savanna, however. They will only take the intermediate areas that have been invaded by juniper, those areas transitioning to a woodland ecosystem.

 

Which is where the Warbler and the Vireo come in.

 

“We want to know where the birds are so we can work around them,” AWU Environmental Conservation Program Manager Kevin Thuesen told In Fact Daily. “We can cut in their habitat but we don’t want to cut while they’re there because that might be harmful to the organisms. We don’t want to upset their habitat. If we know, for example, that a Gold-Cheeked Warbler is living in a particular area between March and August, we can plan our treatments around that.” Warblers and Vireos generally occupy woodland areas but not prairies or savannas.

 

The use of prescribed fire, Thuesen said, can help both increase the amount of savanna and prairie and manage the habitat of the Vireo. 

 

The AWU received for the survey and inventory contracts, which include 16 line items that correspond to individual areas in the WQPL. The Water and Wastewater Commission recommendation would award 10 of those items to Baer, at a cost of $51,313, and the remaining six to Hicks and Company, at a cost of $57,072.

 

According to AWU documents, this will be the first large-scale survey effort conducted on WQPL lands since 2003.