A Common Merganser Hunch Pays Off, Greenville County, South Carolina, January 14, 2023

It was 8:45 in the morning on January 14th when I got a call from my birding friend Gary Harbour.  He had just seen a pair of Common Mergansers on Tankersley Lake in Greenville County, SC.  Common Merganser is quite a rarity this far south, so it was definitely one I wanted to chase.  The problem was that I was just about to lead a bird walk for the Blue Ridge Audubon Chapter and couldn’t break free right away.  That is unless no one showed up.  You see it was bitterly cold that morning with light snow so not the best birding conditions.  But one birder did come for the walk, and we stayed out for an hour until we just got too cold.  As soon as I got back to the car I punched in the coordinates for Tankersley Lake and started the 30-minute drive south. 

I finally arrived at 10:30 and quickly found a good spot to park to view almost the entire lake.  But it didn’t take long to realize there were no Mergansers there.  The only waterfowl were a pair of Buffleheads.  I got out of the car and walked a short distance to view a small cove that was not visible from the car, but still no Mergansers.  What to do... Perhaps they had moved on.  Or just maybe they were out feeding in one of several fast-flowing rivers in the area.  Ever the optimist, I decided to drive the roads in the area hoping to see the Mergs on one of those rivers.  But it was like finding a needle in a haystack because I could only see small portions of the rivers, and most views were obstructed.  After a few minutes I gave up and headed home.

After I got home I did some eBird research and found out that these Mergansers were actually first spotted the evening of the 13th.  Then of course they were seen again early in the morning of the 14th, but gone by mid-morning.  Perhaps the Mergs were roosting on the lake at night and feeding in the rivers during the daytime.  That was the story with a several Common Mergansers at Beaver Lake in Buncombe County the previous winter.  There were several reports of birders observing them flying into the lake near sunset.  I was finally able to catch up with them at first light one early morning, watching them fly off the lake still 15 minutes before sunrise.  If the SC birds were using the same routine, perhaps I could see them as they return to the lake near sunset.  I decided to give it a try that evening.

I arrived back at Tankersley Lake at 5:20, 20 minutes before sunset.  I quickly scanned the lake in hopes that the Mergs had already returned, but only found the same pair of Buffleheads.  It was time to start my “Merganser watch”.  I parked the car so that I could sit inside out of the wind and still view the lake, also using the car as a blind to not scare them off.  I figured there would still be enough light to see them fly in as late as 30 minutes after sunset, or 6:10.  Although I was optimistic initially, that optimism waned as it got later and darker. 

But then at 5:37 I spotted a pair of large waterfowl flying low overhead, passing directly over my car.  They were close enough that with binocular views I could confirm it was the male and female pair of Common Mergansers.  My hunch had paid off – they had returned to the lake.  The Mergansers turned as if to circle and I expected they would come in for a landing.  But instead, they kept flying to the south out of view.  They were only in view for about 10 seconds so it sure was good that my attention was focused on the lake as they passed by. 

There are other lakes in the area so maybe they were going to roost elsewhere tonight.  Or maybe they would still come back to Tankersley Lake a bit later.  I thought about staying to see if they returned, but I was getting cold and dinner awaited, so I decided to head out content to have had brief but good views of a new statebird, #295 for my SC statelist.

My statebird map for Common Merganser is inserted below.  The blue-shaded states are those where I’ve seen this species in its regular range.  The 5 cross-hatched states are those in its normal range where I’ve yet to see it.  And now I’ve seen Common Merganser as a rarity in SC along with NC (the states shaded in brown).  Here in the southeast I call it the “Not so Common Merganser”.