Results 1 to 14 of 14

Thread: The science of duck movement

  1. #1
    Join Date
    Sep 2001
    Location
    Wateree, South Carolina
    Posts
    48,811

    Default The science of duck movement

    Smith: Isotope analysis of feathers offers new insight into waterfowl movements and reveals some surprises
    Paul A. Smith
    Milwaukee Journal Sentinel

    Analysis of isotopes in waterfowl feathers is increasingly informing scientists about bird movements and may help wildlife biologists in efforts to improve duck and goose harvest regulations. The isotopes show unique signatures in feathers and indicate the birds area of origin.

    Tagging animals is among the oldest and most valuable techniques in wildlife management.

    Before its use, many questions could only be met with guesses. Where does a species migrate? What is the size of the animals' home range? Do they have fidelity to a breeding site? How long do they live?

    According to historical accounts, the first record of bird banding occurred in 1595, when a peregrine falcon owned by Henry IV of France flew off after a hawk and turned up 1,350 miles away.

    John James Audubon is credited with the first such activity in North America; he placed silver cord on a brood of phoebes in 1803.

    Over the last century the practice has proven particularly important in the field of waterfowl management. The U.S. Fish and Wildlife Service has more than 70 million banding records on file, with most since the 1960s but some dating to 1914.

    Any state that offers a hunting season for a migratory species must participate in banding. The information from band returns on hunter-killed birds is used to help protect populations and guide decisions on bag limits and season dates.

    The technique has known limitations, however.

    It's not possible to tag ducks in all production areas, for example, leaving gaps in the database. And unless a bird is banded at a very young age, it's not known where it was hatched.

    An aluminum band is shown on a male lesser scaup, or bluebill. The bird was banded in 2013 in Louisiana and killed by a hunter in 2019 in Manitoba. The information does not, however, allow scientists to know where the bird was hatched.
    But a promising new technology has come on the scene that could be a game changer for wildlife managers.

    It's being referred to as a "stable isotope approach" to determining where a bird was hatched or molted.

    Drew Fowler, migratory game bird research scientist with the Wisconsin Department of Natural Resources, dedicated a portion of his presentation to isotope tracking at a Aug. 31 waterfowl meeting hosted by the Wisconsin Wildlife Federation.

    As birds hatch, eat and grow, the water they consume produces a unique signature of hydrogen isotopes in their feathers, Fowler said. The same is true of adult birds that settle in an area to molt.

    Scientists have mapped gradients of these isotopes called a feather isoscape across latitudes in North America, sort of like stripes on a honey bee.

    "It's early, but it looks like this could be really helpful as we seek to constantly improve our understanding of where birds originate and where they are harvested," Fowler said.

    Matthew Palumbo, a researcher with Western University in London, Ontario, is the lead author on two papers published on the technique in the last year.

    That work, conducted in Ontario on mallards and blue-winged teal, revealed some striking differences from long-held beliefs about the origins of hunter-killed birds.

    In a nutshell, the hunter harvest was made up of a much lower percentage of locally-produced birds than indicated from decades of banding data.

    For example in the mallard study, only 3% to 22% of birds killed by hunters in southern Ontario were produced locally, whereas wildlife managers expected it to be well more than half.

    Most of the harvested birds were from areas of Canada farther north and west of the sites they were killed.

    Would work in Wisconsin produce similar eye-opening results?

    "We're always looking to use the best science we can," said Taylor Finger, DNR migratory bird ecologist. "We will definitely be looking at ways to incorporate this into our management."

    Since waterfowl biologists attempt to protect local populations from overharvest, the information is very important.

    About 200,000 ducks are banded annually in North America, and 90,000 bands are reported. The band returns are important for wildlife managers as they study harvest and survival rates and develop waterfowl hunting regulations.

    Banding will likely always play a role in wildlife science.

    But since it is labor intensive in the best of circumstances, and impossible in others, the isotope analysis could portend a new era, especially in waterfowl management.

    The isotope technique has multiple advantages. It only requires a feather be turned in from a bird, dead or alive, and never requires the bird to be trapped and banded.

    Among its disadvantages is its lack of specificity. The feather isoscapes are more than 100 miles wide in most areas.

    Still, it represents an exciting potential for waterfowl managers.

    The Wisconsin DNR is on the cutting edge of using the technology.

    Finger said the agency is developing a library of isotope data from birds known to nest in the state, including mallards, wood ducks, blue-winged teal and ring-necked ducks. It will then analyze feathers from birds harvested by hunters to learn where the birds originated.

    "For years we have made the assumption based on band recoveries that 70% of mallards we harvest in Wisconsin were produced in Wisconsin," Finger said. "This new work may lead us to a whole new understanding of where the birds are coming from."

    I tip my cap to Finger, Fowler and the rest of the DNR waterfowl staff for keeping their eyes open for new technology and, when opportunities arise, continually improving their management techniques.

    More on waterfowl
    For the second consecutive year Mark Kakatsch, Wisconsin Wildlife Federation migratory committee chairman, organized a waterfowl summit in late August. Due to the coronavirus pandemic, this year the meeting was held virtually.

    In addition to Fowler, it included presentations by Finger, DNR chief warden Casey Krueger and Bruce Ross, executive director of the Wisconsin Waterfowl Association.

    Freelance outdoors writer Tim Eisele, Wisconsin Conservation Congress member Paul Gettlefinger, WWF executive director George Meyer, Ducks Unlimited member Nels Swenson and I were among those who participated.

    I'll have coverage of other topics from the meeting, but here are a couple of nuggets: Finger said Wisconsin and the other states in the Mississippi Flyway have requested a five bird daily bag limit for Canada geese, possibly to begin in the 2021 season; and a Wisconsin waterfowl expo is being planned for August 2021 in Oshkosh.

    https://www.jsonline.com/story/sport...nt/3470881001/

  2. #2
    Join Date
    Jul 2013
    Location
    Edisto River
    Posts
    653

    Default

    Pretty cool if it proves to be accurate, could really be a game changer for the future of waterfowl. Thanks for sharing
    Quote Originally Posted by Buckin Bronco View Post
    Yep. I have a border collie mix that is smarter than most of the people on this site.
    The greatest trick the Devil ever pulled was convincing the world he didn't exist.

  3. #3
    Join Date
    Nov 2001
    Location
    Columbia, SC
    Posts
    47,894

    Default

    it will be interesting to see what man does to the migration without any US hunters in canada. then, to see what ducks do when they hit the dakotas and get shot at more than usual.
    Ugh. Stupid people piss me off.

  4. #4
    Join Date
    Sep 2001
    Location
    Wateree, South Carolina
    Posts
    48,811

    Default

    I am no scientist, but I expect some will fly away while others fall to the ground as they expire.

  5. #5
    Join Date
    Dec 2005
    Location
    Ballard's Landing
    Posts
    15,425

    Default

    Fair assessment Johnny.
    Be proactive about improving public waterfowl habitat in South Carolina. It's not going to happen by itself, and our help is needed. We have the potential to winter thousands of waterfowl on public grounds if we fight for it.

  6. #6
    Join Date
    Nov 2001
    Location
    Columbia, SC
    Posts
    47,894

    Default

    certainly probable.
    that being said, we will see if man has anything to do with (micro)migration out of canada.
    Ugh. Stupid people piss me off.

  7. #7
    Join Date
    Sep 2001
    Location
    Wateree, South Carolina
    Posts
    48,811

    Default

    Or, at the very least, we will get 5011thousand anecdotal stories about how every group sees it. My observation is that the duck death numbers north of the border are not putting any meaningful dent in the migration, and the migration crossing south itself comes as a product of freeze more than foodXpressure to the tenth power.

    Ducks are ducks. If you are hunting a slothful pack of 100,000 greenheads that goes out to a peafield and barley by the clock, work on them, they won't change. Add a bunch of locals, and a guide service moves in, they don't get their passports and head for the US. They go to a 1000 acre lake, sit in the middle, and feed 2 minutes after shooting time just like here...

  8. #8
    Join Date
    Nov 2001
    Location
    Green Pond SC
    Posts
    1,441

    Default

    50 outfitters shooting 100 ducks per day x 30 days = 150,000 dead ducks
    “The price of freedom is eternal vigilance” - Thomas Jefferson

  9. #9
    Join Date
    Mar 2003
    Location
    Gobbler's Knob, GA/ Bamberg,SC
    Posts
    21,442

    Default

    I just want more Black ducks to come where I am. ( Like they used to). Yall can have the rest of em.
    F**K Cancer

    Just Damn.

  10. #10
    Join Date
    Aug 2008
    Posts
    1,895

    Default

    I need to figure out a damn way to get across the border.
    AADC48DD-DE02-4733-AB1C-FAB4AC67962B.jpg

  11. #11
    Join Date
    Nov 2008
    Location
    Summerville
    Posts
    5,583

    Default

    Turn off your lights and we'll smash the ducks this year

    https://www.birds.cornell.edu/home/v...C7UXKLbaGQ-hkA

  12. #12
    Join Date
    Sep 2001
    Location
    Wateree, South Carolina
    Posts
    48,811

    Default

    Quote Originally Posted by swampknob View Post
    I need to figure out a damn way to get across the border.
    Don't do it for the steak. Theirs tastes like shit unless the US is giving corn away...

  13. #13
    Join Date
    Sep 2001
    Location
    Wateree, South Carolina
    Posts
    48,811

    Default

    Quote Originally Posted by Palmetto Pride View Post
    50 outfitters shooting 100 ducks per day x 30 days = 150,000 dead ducks
    Sounds like a lot. I expect it is more though. I think 3 states kill over a million in 60 days here. A few more over 500,000.

    It sure used to be more. Louisiana was killing 2.5 million not many years ago and are now at 550,000 or so...

  14. #14
    Join Date
    Nov 2001
    Location
    Columbia, SC
    Posts
    47,894

    Default

    i dont think its going to affect the migration like weather...i'm just wondering about little micro-migratory changes to "duck" all the guns in the US at the border. I think it would be plausible that the ducks dont spend much time in ND this year....
    Ugh. Stupid people piss me off.

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •