Update from Sleeping Bear Dunes NLS on Waterfowl Mortality

Hello All,

The first real increase in observed mortality for the fall season seems to be underway. AMBLE monitors at SLBE reported Oct.17-18 about 24 red-breasted mergansers, 6 white-winged scoters, and a few cormorants and gulls, one dead loon, and a sick loon reported. These reports from Platte River area to Empire, and Sleeping Bear Point (approx. 15 miles of beach). Yesterday I assisted on Transect 5 (1.8 miles) near N. Bar Lake, where about 18 more mergansers were found, mostly red-breasted (some still out in the heavy surf from our ongoing strong winds), a scoter and a loon were also collected. Preliminary observations this morning at Good Harbor Bay and Glen Haven showed only 1 horned grebe found dead .

As these observations coincide exactly with the timing of heavy loon, scoter, and long-tailed duck losses last year during this week, we will be paying close attention during the next few days. 

In comparison to last year, our annual mortality is way down. We had some anecdotal reports during the shutdown (seems some citizens are ever vigilant) which indicated the continuation of the previous trend of relatively light mortality along the lakeshore, there was fairly light mortality observed during  monitoring trips in Aug. and Sept.of this year on the Manitous, and with these recent additions from mainland transects, we probably still are below 200 total birds (3 loons). Last season end of year total approx.1500 (580 dead, 4 sick loons). Several days of strong winds and waves were a common factor last year and this year during these observed events.

We will keep you informed.

Thanks,

Dan

Dan Ray

Avian Botulism Monitoring Project Lead
Sleeping Bear Dunes National Lakeshore
9922 Front Street
Empire, MI 49630    
231 326-5834 x606  
dan_ray@nps.gov