See below some duck data for the past 20 seasons in SC...I'll take the credit for the upward trends in Goldeneye and Eider harvest. Longtailed ducks should show positive too once the 2020-21 season info is released but it's not statistically meaningful because so few are killed in SC. What is meaningful and not surprising is the the average mallard harvest has dropped from around 35k in the early 2000's to 12k in recent years. USFWS reports on "Domestic Mallards" but they are not very good at separating tamies and boat ramp mallards from wild mallards from just the wing. I had a drake mottled duck get reported as a hen domestic Mallard. I believe that a lot of the mallards being reported are actually release mallards only because I believe there are way more than 4,000 tamies killed in SC.
What may surprise folks is that Woodduck numbers are starting to weaken. We might have had too many seasons with a 3 bird limit. Wood duck harvest jumped up in 2008-09 which was the first season of 3 birds. It was good for a little while but seems to be dropping to previous levels even with the higher limit. It might be time to make the big boy decision to bring it back to two.
The trend calculation is nothing fancy - Least squares slope over long-term average but it shows, I think, a meaningful trajectory.
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