In Chanhassen I had 12% Merganser nests in 2012, while last year it was 88%. 2013 was almost as high too. So what the heck is going on?
I brought it up at the Wood Duck Society mtg today. Others in the west metro saw the same unprecedented spike. A biologist opined that it was likely due to the late springs the last 2 years. basically there is ice north of us, the sun is telling them it's time for breeding, so they took over the WDB. Also remember that the Mergies are here 1 to 2 weeks before the Woodies are. So once they are in the box, the Woodie is SOL.
Also, a new study is due out later this summer for WI in which every 20 years they do an intensive bird survey. Some feel the Mergy range has pushed further South. We shall see it that is a factor too.
So we shall see if the Mergy usage drops back down to less than 20% for the 2015 season since we have an earlier spring and the Mergies can head north.
I had a 1st on a set check a few weeks back. I had a combo up in Victoria (WDB and MHN on same post). So I had a Mergy in the box above, a Mallard in the center of the MHN, and on the north end of the hole of the MHN - another Mergy had a nest. Like I mentioned above--the Mergies took over last year!
At the WDS mtg, it was presented on that Horicon Marsh 3 years ago had the 1st ever documented Bufflehead use a WDB ever in WI. Yes the Bufflehead is a cavity nester too. But it is very rare to nest in the US as the nest in the Boreal forests of Canada. I saw lots of Bufflehaeds on the ponds in the west metro today.
I heard this as a tip to increase usage of WDB. On the sides, spray paint black a 4x3 sized oval to mimic a cavity. A guy swears it increased his box usage by over 25%. He was all "oh yeah riiiiight...sure... " when he 1st heard of it 2.5 years ago, so he tried it on some of his boxes and it worked. So a year ago he spray painted the black ovals on all of his boxes and the % of use jumped. he said it sound hokey, but that is indeed works. The theory is that as they fly by it is easier for the Woodies to see the dark spot and so they investigate. And then they find the hole on the front of the box. And now you have a nesting pair.
I will not be doing it this year to the existing boxes since they are all maintained no and I also want to see a comparison as they are on Mergy use this year. But I have 5 new boxes on land going up shortly and will try it on them.
The Woodies started appearing last weekend and many are now around and paired up. Nothing on the nests yet, but they will be nesting shortly.
And to cap off the day, 1/2 hr ago I heard a flock of Tundra Swans winging Northwards.
Life is Good.
