New publication co-authored by Point Blue scientists
Posted: 27 Mar 2017 01:49 PM PDT See full ScienceDaily article here
Reduced seasonal flooding of wetlands and farm fields in California’s Sacramento Valley threatens a key stopover site for migratory shorebirds, a new study shows. Landsat satellite images reveal that flooded habitat is most limited during peak spring migration when the birds urgently need resting and feeding sites. Near the peak of migration, an area of seasonally flooded land twice the size of Washington, D.C. has been lost since 1983….
The researchers’ analysis of historical biweekly NASA Landsat satellite images of the valley reveals that flooded habitat near the peak time of spring migration has shrunk by more than twice the size of Washington, D.C. over the last 30 years.
“On average, we’re losing an area about four times the size of Central Park each year, during a critical window of time in late March,” said Danica Schaffer-Smith, a doctoral student at Duke’s Nicholas School of the Environment, who conducted the study with researchers from the nonprofit Point Blue Conservation Science.
More than half of all shorebird species in the Western hemisphere are now in decline, Schaffer-Smith noted….
…During the worst of the recent drought years, conservation organizations [The Nature Conservancy, Point Blue Conservation Science, CA Rice Commission, Cornell Lab of Ornithology and others] joined forces to launch BirdReturns, a payment-for-services program that compensated farmers for flooding their fields to provide additional habitat for birds, Schaffer-Smith said. The new study’s findings could help guide the future timing and location of such initiatives.
“Years of drought have heightened scrutiny of water use in California to the point that even rice farmers have begun to explore a switch to drip irrigation to conserve water, but these fields provide important habitat where wetlands have been lost,” she said. Schaffer-Smith and her colleagues published their peer-reviewed paper this month in the journal Remote Sensing of Environment. The study is freely available online through May 3, 2017.
“Satellite imagery can help us get the biggest bang for our buck by targeting conservation initiatives in a specific window of time at key locations,” she said. “Landsat is the longest running Earth observation satellite system we have, and free access to this data enables researchers to look at the effects of seasonality, climate cycles, and long-term trends in land-use change.”
Danica Schaffer-Smith, Jennifer J. Swenson, Blake Barbaree, Matthew E. Reiter. Three decades of Landsat-derived spring surface water dynamics in an agricultural wetland mosaic; Implications for migratory shorebirds. Remote Sensing of Environment, 2017; 193: 180 DOI: 10.1016/j.rse.2017.02.016
Note: Dr. Matt Reiter is a Point Blue Quantitative Ecologist and Blake Barbaree is a Point Blue Avian Habitat Ecologist. Danica is supported by a PhD fellowship from NASA that Dr. Matt Reiter helped her with in early 2013.