Monday, March 9, 2009

Lead Poisoning

Numbers of birds, especially trumpeter swans, treated for lead poisoning at the Raptor Education Group Inc. (REGI) in Antigo Wisconsin has increased in the past few months. Normally, REGI only gets a few trumpeter swans to rehabilitate every year. Since December they have already gotten a dozen. While most of the swans have been successfully rehabilitated, some have died due to the high concentrations of lead in them: up to 65 lead pellets. Mostly these are shotgun pellets and lead fishing tackle, which is why LoonWatch is working tirelessly on the Get the Lead Out! initiative, which educates anglers about the dangers of using lead tackle and provides alternative options. Even though lead shotgun pellets have been outlawed for over 20 years for waterfowl hunting, there is still plenty of lead in lakes and streams because lead is water insoluble and stays at the bottom of lakes and streams forever unless physically taken out. And it's not only REGI that is getting more trumpeters than usual, the avian rehab center in Minnesota has had 30 come in since the fall, when 24 for an entire year is typical.

While nobody knows for certain why trumpeter swans have been ingesting more lead lately, two explanations have surfaced. One is that the Midwest has recently experienced several droughts, which have lowered lake levels enough that swans can now reach more of the bottom of lakes, thus exposing them to lead pellets that have sunk there in the past. Another possible factor is the fact that both the Wisconsin and Minnesota DNRs have placed a feeding moratorium on trumpeter swans, meaning that the DNR no longer feeds the swans and it is illegal for anyone else to do so either, due to concerns that high densities of swans around the feeding areas might facilitate the spreading of diseases. It is thought that the feeding moratorium caused the swans to go to new feeding grounds, where they ate the lead. This moratorium has since been lifted, and both DNRs have resumed feeding the swans.
For more information about lead poisoning in swans, click here.
To see pictures of a swan release, click here.

1 comment:

Peg Abbott said...

We at the Trumpeter Swan Society are also deeply concerned about the lead issue and appreciate this posting. On the website you can find details on an excellent documentary produced in Canada on this subject - 'Mystery of the Toxic Swans'. There is also a progress report on 2008-2009 lead issues in Washington State, where hazing operations have occurred to move swans off lakes known to have high levels. Just scroll down through the news section of I will make sure that Martha Jordon, our Director-at-Large working diligently on lead issues sees your post as well. Peg Abbott, Membership and Outreach, Trumpeter Swan Society