Eared Grebe survey results from 2015March 24th, 2016 by Robbie, Restoration Field Technician
Mono Lake is a critical migratory staging ground for Eared Grebes (Podiceps nigricollis). Surveys have confirmed that 30–50% of the entire continent’s population of Eared Grebes utilize Mono Lake, with over one million birds visiting on their fall migration route to feed on brine shrimp. Since 2008 the Mono Lake Committee has collaborated with Canadian research biologist Sean Boyd from the Pacific Wildlife Research Centre in British Colombia to carry out annual aerial Eared Grebe surveys.
It had previously been observed that Eared Grebes were most prolific at Mono Lake in mid-October (as recently as 2013), but aerial surveys from subsequent years suggest that a shift toward an earlier peak might be occurring. In order to capture this potential shift in the Eared Grebe migratory timing, we increased the number of survey flights in 2013, 2014, and 2015 to include five flights from mid-September to mid-November instead of only one flight in mid-October. Results from 2014 and 2015 counts show that peak grebe abundance is happening earlier, meaning that additional surveys may need to be conducted in early September.
This critical research would not be possible without the help of volunteer pilot Geoff Pope, flight sponsor LightHawk, volunteer photographers, and volunteer grebe counters—thank you all. Together we are working to better understand Eared Grebes and conditions at Mono Lake.
This post was also published as an article in the Winter & Spring 2016 Mono Lake Newsletter (page 7).