January 28, 2015
Contributions by the GECSC National Land Cover Database (NLCD) Team have been included in recent updates to the 2011 NLCD, which now includes Alaska. The GECSC NLCD Team (Cartographers Catherine Costello and Rick Poss and Physical Scientist Lori Baer) is currently performing an accuracy assessment of the 2011 database for the conterminous U.S, developing improved methods and procedures for producing its 2016 edition, as well as working on procedures for producing a NLCD for the 1990's and 1980's. The overall purpose of the NLCD is to provide complete, current, consistent, and public domain information on the Nation's land cover.
January 26, 2015
Optimizing conservation strategies for Mexican free-tailed bats: A population viability and ecosystem services approach
By Ruscena Wiederholt, Laura López-Hoffman, Colleen Svancara, Wayne Thogmartin, Gary McCracken, Jay Diffendorfer (GECSC), Ken Bagstad (GECSC), Paul Cryan, Amy Russell, Darius Semmens (GECSC), and Rodrigo Medellín. Published in Biodiversity and Conservation
This article presents a conservation prioritization method for maternity roosts of the Mexican free-tailed bat, a species that winters in central and southern Mexico and migrates north to large maternity roosts in the southwestern U.S. and northern Mexico. These bats provide valuable ecosystem services such as insect pest-suppression in agricultural areas and recreational viewing opportunities. Using data on each roost's contribution to the species' population viability, ecosystem services provided, and risks to the roost structure and bat population within a multi-attribute utility function, we demonstrate the most critical maternity roosts to protect, which can aid in conservation of the species.
January 21, 2015
Directly dated MIS 3 lake-level record from Lake Manix, Mojave Desert, California, USA
By Marith Reheis (GECSC), David Miller, John McGeehin, Joanna Redwine, Charles Oviatt, and Jordon Bright. Published in Quaternary Research.
This study found that during marine isotope stage 3 (MIS 3), at least eight highstands of Lake Manix occurred from about 45,000 to 25,000 years ago. The ages of these highstands, representing cool wet conditions in southern California, correlate to Dansgaard-Oeschger stadials recorded in Greenland and the North Atlantic. These high lake levels in such a low-latitude desert setting as the Manix basin require significant rearrangements of atmospheric circulation and suggest that the southern lakes were sustained by greatly increased precipitation from tropical sources.