Advocate Editorial Board opinion: One survey of whoopers isn't look at complete picture
By By the Advocate Editorial Board
Jan. 7, 2014 at 6:03 p.m.
Updated Jan. 6, 2014 at 7:07 p.m.
The whooping cranes have been in the Aransas National Wildlife Refuge since November. The endangered birds will spend the winter and early spring months here before flying back to Canada in April.
The Aransas flock is the last remaining natural migratory flock, and we are proud to know it has a safe refuge in our area. The cranes are part of an important ecosystem balance that both private citizens and government agencies have worked hard to maintain. But some elements of those preservation efforts are still adjusting.
According to a previous article, one group, the International Crane Foundation, says the method used by the U.S. Fish and Wildlife Service to survey the population of cranes is providing an incomplete set of data. The previous method employed was a census conducted by Tom Stehn, retired whooping crane coordinator for the wildlife service, that attempted to count each individual crane throughout the season using weekly flights over the refuge. Now, the survey method looks at a portion of the population over a one-month period and uses a mathematical equation to estimate how many cranes there are this year.
In order to fill in the blanks, the foundation is conducting its own count along 10 miles of shoreline up the Intracoastal Waterway on the east side of Blackjack Peninsula - about 20 percent of the cranes' habitat - for the third year. The count is meant to examine the status of a subset of the population.
We are glad to see both the U.S. Fish and Wildlife Service and a private nonprofit are collecting information on this endangered species. Whooping cranes rely on a delicate balance that includes freshwater flow, water salinity, food availability and more. The survey method, while not as specific as a census, offers a general spectrum of the number of cranes in the refuge, but the limited time used to count the cranes seems counterintuitive. The crane population can fluctuate as the season progresses. Birds do not die during a specific time period. It would be better to find a way to offer updated surveys throughout the season to keep tabs on the population rather than taking a count at the beginning of the season and hoping there are no significant changes.
We applaud everyone who plays a part in protecting this important, valuable species. But because the species is so important to the Aransas refuge ecosystem, we encourage the government to develop a more extensive counting system that will provide a more complete picture of how the population changes throughout the season. The more data that is available, the better we can protect these endangered birds.
This editorial reflects the views of the Victoria Advocate's editorial board.