Waterfowl Mid-Winter Index (MWI) - A Sinking Ship ?

[Tuffy]

While looking into the Santee NWR counts, I realized that I had not updated the larger MWI data in quite a while. It looks like that won't be a problem in the future. 2015 would appear to be the last year that this will be done on a national level. It has always been a state responsibility, but FWS has always provided a lot of support. As that declines, more and more states are opting out and/or greatly reducing their efforts. States in the Miss. Flyway are holding on for a while longer, but (for example) the AF is putting their resources into Seaducks and Brant for Harvest Management purposes.

Over time, I'll try to graph some wrap-ups of what it has told us about ducks in S.C., but the picture won't really be much of a surprise. Mallards left us in the early 80s and today is all about Gadwall, GW Teal, Shovelers, and (yes) Ring-Necks. I'm afraid that our share of the wintering birds in the Flyway has only shown signs of increasing for the Gadwall, though. As I've said, they are our opportunity. The GW would be, but they seem to be wintering further north more often. There are Rings, but the AF has not been increasing and our share of them has been pretty consistent except for part of the 80s.

[Tuffy]

Let me see how this might look. First, this is the raw graph of the MWI in SC over the years. There may be a wee bit of encouragement there in the last few years.

mwi_sc.jpg

[Tuffy]

That might make us wonder if the ups and down were a pure SC thing or the result of changes to the Atlantic Flyway. The answer seems to be that our "share" has declined for some, but not so much recently for Gadwall and Ring-Necks.

[Tuffy]

I guess we have to take the inevitable look at what our share of the total US MWI has been for these species. It doesn't make me feel better.

[Tuffy]

Finally, at this level, we might want to see how the mix of MWI species in S.C. has changed over the years. For better-or-worse, I think this IS the story for us. The Rings, Gadwall, and GW are where-it's-at for us. IMO, that means that we need to FOCUS on these as much as possible.

[Palmetto Pride]

Well done.

Hydrilla would be nice for Gadwall and Ringos

[Tuffy]

Well done.

Hydrilla would be nice for Gadwall and Ringos

Probably, but notice that we had a much larger share of all Rings in the U.S. long before we think we had hydrilla. It did slow the share decline in the early 90s, but why they aren't here is a reflection of something larger, I do believe. Notice how the entire AF seems to look very much like the SC experience for them over the decades.

mwi_ring_share_us.jpg

[buckpro]

When is the midwinter index usually taken?

[Tuffy]

Supposed to be early in January

[Tuffy]

Gadwall: This has potential to "replace" the Mallard of the old days.

[Tuffy]

GW Teal: They're doing alright, but seem to be wintering further north, like Atlantic Flyway Mallards.

[buckpro]

Supposed to be early in January

Forgive my ignorance, but how are these counts taken and where? If that charts is for the entire state, I think its way off. Only 100K ducks?

There is no doubt though, gadwall is our new mallard. Killed a banded one this year, interesting enough, he was banded on 2/20/2015 in sandusky Ohio. It wasn't over 20 degrees that entire week he was banded, amazed he was up there. Wish they would band more.

[Tuffy]

How it was done was always left up to the individual states, but they all consisted of plane, boat, and auto surveys of what was considered to be the primary wintering habitat in each state. To the extent that was true, the results became an "Index" that could be used to compare changes over the years and, hopefully, changes between states and flyways. There are books and papers both defending it and criticizing it over the years, but it was the only view of winter distributions that we had except for Harvest Estimates and the band recoveries primarily associated with them.

In South Carolina, I think that we made a small number of changes to the methodology over the years, as did most of the states. The MWI was also considered to be ineffective at capturing a few species such as Wood Ducks and Sea Ducks. Recently, it's probably missing some significant number of birds on private impoundments, large and small, but none of that nullified its value as an Index to compare years and states.....in my view.

At any rate, it is pretty much history now and the point here was to see what it seemed to tell us over the years.

[JABIII]

I believe the numbers to be generally worthless. They are not even close. However, the trends are unmistakable.

[Rubberhead*]

I believe the numbers to be generally worthless. They are not even close. However, the trends are unmistakable.

Yep. If you count wrong, at least do it wrong the same way every year.

[buckpro]

Got it, thanks for the info and input. I’d love to see any written reports from previous flights/observations. Wasn’t the Kennedy Waterfowl Center going to start conducting counts/flights?

I know 2 years ago they did the survey flights in our area on the last day of duck season, guess they were hoping to get a good count of birds resting on WMAs and refuges. Scared the shit out of me, he dropped down in the pond 50 yards from our blind.

[Tuffy]

I don't mind the difference between an "inventory" and an "index", but it has always bothered me that I cannot easily determine the exact locations/routes that are included. I've never been able to find it.

(But I should add that I am confident in how it was selected and maintained over time.)

[uga_dawg]

Pretty interesting trends. Thanks putting together

[Strick9]

Good work Tuffy, I can't argue your graphs one bit.. I hope our newfound efforts pull up the numbers over the next 3-5 years. We are going to need all the support from hunters that we can get. I can't imagine that DU won't somehow push for the MWIs to continue or start such on their own. Or can I lol.