EXCERPT
Whooping Crane Recovery Activities March - August, 2001
By Tom Stehn
U.S.F.W.S Whooping Crane Coordinator

 (bold font and underscore for emphasis by RFA / TEXAS)

  The drought at Aransas continued throughout the spring and summer. Heavy rains August 26-31 brought some relief. In a six-day period, the refuge received 8.5 inches of rain. The town of Tivoli located 15 miles north of Aransas received an unofficial total of 22 inches which flooded the Guadalupe River bottoms. This was a most welcome sight since freshwater inflows on the Guadalupe River are needed to aid blue crab reproduction. The human reduction of freshwater inflows is a huge threat to the whooping crane that could lead to extinction. Data from the last eight winters indicates a direct relationship between freshwater inflows on the Guadalupe River, blue crab populations, and whooping crane survival. When inflows are high, blue crabs populations increase due to enhanced reproduction and survival, and whooping crane mortality is low. With reduced inflows, crabs do poorly and whooping crane mortality rises dramatically. This makes sense since blue crabs make up 80-90% of the whooping crane diet. In 2 of the last 8 winters when crabs were scarce, whooping crane mortality was 7 and 6 birds, respectively. In the other 6 winters with adequate crab populations, whooping crane mortality was only 0 or 1 bird annually. Also, whooping cranes have to fly to seek out freshwater to drink which forces them to use energy whenever marsh salinities, which are affected directly by inflows, exceed 23 parts per thousand.

  With projections over the next 50 years that human uses of water will reduce inflows and decrease blue crab populations by at least 8 %, this is going to have an alarming impact on whooping cranes. With the population of Texas predicted to double in the next 50 years, the Texas legislature has initiated a state-wide water planning effort. As water developers plan to take water from the rivers, there is no direct mechanism in Texas water law to provide freshwater inflows to the bays and estuaries. Basically, the bays get whatever is leftover, and portions of Texas rivers are already over-appropriated. The Rio Grande River made national news this summer when its flows no longer reached the Gulf of Mexico.

  The U.S. Fish and Wildlife Service must take a strong stand on the inflow / whooping crane issue. All conservation groups need to do all in their power to ensure that adequate inflows from the Guadalupe River reach the bays. The Service has written a letter of support for the San Marcos River Foundation's application for 1.15 million acre-feet of water that would remain in the river for wildlife. This is the amount of water identified by Texas Parks and Wildlife Department needed to keep the bays productive. The San Marcos River Foundation's water rights application is an important step in ensuring inflows on the Guadalupe reach the bays. It would be precedent setting in Texas for a water right to be designated as an inflow. Water developers are contesting the application. They are saying that human needs for water are too great and that there isn't enough water available to provide the water identified by the Texas Parks and Wildlife Department study. This issue has everyone's attention, and support is needed if the San Marcos River Foundation's application is to be successful.