DuckSouth.com

Thank you Steel 3's. It's nice to have a waterfowl biologist that has studied the duck populations for 20 years and done spy-blind studies stop by from time to time to help out! (in addition to the other waterfowl biologist who must be out fishing right now )

The study is flawed. They should have removed the SWD from the spread when off. The Kill/wound ratio and the range/no range ratios follow each other hand in hand. I think you would observe the same if you measured decoys on still water vrs. decoys in slight wind. A motionless bird suspended two to three feet above the water is going to flare birds, increase cripple ratio, and decrease close shots.

The most interesting statement in this report is that there was no dicerrnable difference in body mass. Given the affore statement I guess we could assume that a bird that is going to commit is going to commit, and that you will flare twice as many birds with a bad spread.

dawg, I'm guessing the 3 minute pause between on and off periods was for removal or setup of the spinner and to bring in new hunters for when the spinner was on.

I think we can all agree the testing was a bit flawed in many ways.

It always amazes me the armchair statisticians and epidemiologists who can instantly, via viewing the internet, design a better peer reviewed study than PhD professionals in the field.

What about the Minn. study, the La. study, and the SoDak studies?

Sing with me now: Flaw, Flaw, everywhere a Flaw, blocking out the scenery, breaking my mind.....

if'n you still feel the need for spinners.. call me... i'll brang my goose suit (full body) and i'll run aroun your spread flappin my arms up an down...

research has shown that this method is 100% more likely to f'up your hunt.....

I would still like to know some percentages from the study! If they are saying that you have a 100% better chance of killing ducks with a twirly, then I agree we should remove it, but not unless our Northern brothers do the same!

I don't think the study is saying that however that for what I have read. Or is it?

It is not saying a 100% chance.

I need to dredge up the text of the Minn study from my hard drive. It had all the raw data.

crow wrote:MSBowman, I have a degree in English, but I think I can sipher enought to figure out "1.9 times more" is dang near two times more which is close to double the number killed without. And, I would love to see the figures on how you came to the conclusion that 100 times more is 100%!

Dang, man, where'd you get your education....Georgia?

Naw man. He's a double-naught duk spy. He went ta school with his twin Jethro Bodine. He just didn't quite make it all the way ta the 6th grade.

Perhaps I'm wrong. Maybe they did remove the device. You would think so.

But, it didn't say.... it just said it buffered. In reserch design, you would need to clear the effect of one condition prior to establishing effect of the next. If it were a remote controlled SWD, then an arb. amount of time would be required to nill the effect of the prior condition. To be sure no working birds had been affected by seeing the wings "on" condition.

Maybe this information is detailed in the full body of the report. Normally that's where you find the details.

None of this matters anyway. All it will do in this forum is spark an endless line of opinion...

By the way what is 100% of 1?

The study is flawed. They should have removed the SWD from the spread when off.

All controlled studies are flawed to some extent. None of us change something in our hunting back and forth with the clock; that's not realistic. But a scientific study does so (and accepts the loss of "reality") to control for the effect of other factors like weather that day, duck populations in the area, hunter-quality, etc. Ideally, they want everything to be exactly the same except for the effect they are testing ..... in this case, the spinning wings. Besides the logistical problem of pulling the SWD and replacing it at 15-minute intervals, by doing so you confound the effect of the spinning wings by changing another aspect of the decoy spread at the same time.

Another way to do this type of study is to make entire hunts either with or without the SWD. Because you then inject LOTS of variation in all the other aspects of the hunt, you have to make many, many more hunts so that the variation due to the other factors is "averaged out", and you can see the effect of the SWD. The methods used in this study are clearly more cost-effective.

Someone asked about the position of the wings when the spinner was "off"; the authors say "During the control periods we turned off and adjusted the wings to the horizontal position with the white side facing down".

A motionless bird suspended two to three feet above the water is going to flare birds, increase cripple ratio, and decrease close shots.

Decoys simulating flying birds have been sold and used for decades. I've not seen anything as definitive as you state. If what you say is true, then remote-controls or variable functions (regular on and off) on SWDs would be counter-productive because anytime they are "off" they are flaring birds. However, I've seen numerous testimonies to the contrary.

The Kill/wound ratio and the range/no range ratios follow each other hand in hand.

I'm not sure what you mean by "hand in hand". For MARSH hunts, the probability of a mallard coming within range (40 meters) is 1.9 times higher with the spinner on and the crippling rate is 1.7 times lower. However, there was NO difference in crippling in early-season FIELD hunts despite mallards being 6.4 times as likely to come in range. Even in the late-season FIELD hunts, the crippling rate was only 3.7 times lower with the spinner "on", which IMO is not "hand in hand" with the 6.4 time greater probability of a mallard coming in gunning range.

The most interesting statement in this report is that there was no dicerrnable difference in body mass.

Where did you read that? What the researchers tested was if the "body condition" of the birds killed was different with spinner "on" vs "off" ..... and they were different. Mallards killed with the spinner "on" were in better condition, on average, than those killed with the spinner "off".

The reason we use a condition index instead of just body mass is because a larger bird (larger skeletal size and volume) in poor condition (little body fat, atrophied muscle) can have the same mass as a smaller bird that is in much better condition.

As the authors themselves have concluded, this study is not the end-all to the SWD debate. It's a solid piece of work, but it's mostly the information on crippling rates and body condition that make it noteworthy IMO.

The nationwide crippling rate is 20%, is it not? One bird lost for every 4 brought to blind?

GulfCoast wrote:The nationwide crippling rate is 20%, is it not? One bird lost for every 4 brought to blind?

That's correct. It's the general, long-established crippling rate used by the USFWS to convert the "Harvest Rate" (as reported by hunters via band-recoveries) to the "Kill Rate". Obviously, there is a lot of variation.

GulfCoast wrote:The nationwide crippling rate is 20%, is it not? One bird lost for every 4 brought to blind?

Is that hunting with a twirlie, or without?