Lead and Bald Eagles

I am willing to believe that lead poisoning is a serious issue for wildlife, but I’d be skeptical of automatically blaming lead shot. This article on lead poisoning by bald eagles is interesting, but there are key details I’d want to know that the article doesn’t explore:

When an eagle was found near Ferryville it was apparent that there was something wrong, so the Wisconsin DNR took the bird to Dr. Laura Johnson.

Dr. Johnson says, “She was having seizures, she was really wobbly. Those are really classic signs of lead poisoning.”

With the help from a Gundersen Lutheran pharmacist Dr. Johnson was able to get a hold of an antidote and started treatments.

Unfortunately, most eagles found with lead poisoning aren’t so lucky.

The questions to ask here would be:

  • Were blood levels of lead tested for the bird? Or was the diagnosis made solely the basis of symptoms?
  • If the blood levels were tested, are we sure the lead contamination is a result of ingesting shot?
  • How common is lead poisoning by shot in birds, and does it have a detrimental effect on populations?

Humans have been using lead shot for hundreds of years. Why only now is it a wildlife holocaust? Obviously the Bald Eagle managed to recover the entire time while humans were using lead shot, and given the decline in hunting, it would seem to me that this should be a less serious problem than now. I’m willing to accept that lead shot is a problem, but I’ve seen no good science to show that’s the case yet.

12 Responses to “Lead and Bald Eagles”

  1. Uh, and also bald eagles eat fish mostly. Not a lot of lead shot in fish meat.

  2. “How common is lead poisoning by shot in birds, and does it have a detrimental effect on populations?”

    It’s common enough that people began documenting it over a hundred years ago. This is why bird shot doesn’t contain lead and some places have even regulated lead fishing weights out of existence.

    It’s unusual to see it in higher predator species like eagles though. Generally you find this in waterfowl populations where it was very common as bird’s would ingest lead shot/sinkers as grist to aid digestion. Scavengers who eat carrion killed with lead shot can also show elevated levels.

  3. Weer'd Beard says:

    I suspect the passenger pigeon was wiped from the planet using lead shot. That’s a lot of shot when you think of how many birds there were, and yet we still have nature.

    Seems if these stories were correct the US would look more like the establishing shots from Blade Runner by now….

  4. Humans have been using lead shot for hundreds of years. Why only now is it a wildlife holocaust? …given the decline in hunting, it would seem to me that this should be a less serious problem than now.

    I don’t know the issue, but I’d speculate that the much, much greater human population in the western United States means all centuries-old human behavior can now have a dramatically greater effect.

    Similarly, is hunting declining overall, or per-capita?

    Don’t get me wrong; we shouldn’t restrict other people’s choices “just to be on the safe side” if there’s no hard scientific evidence of harm. But increasing populations erode the value of precedent in determining what’s harmful.

  5. I believe that you will find that the passenger pigeon also suffered from the use of net cannons and explosives to kill whole flocks at once. Lead poisoning should not include having led pellets forcibly entering the bird as it is shot.

    I live in Wisconsin, and there are many up here (mostly in Madison) who would like to see hunting ended in the state. This sounds to me like yet another attempt to get a wedge in place for future hammering.

  6. Chas Clifton says:

    This issue was discussed to death in the 1980s, when the switch to steel shot for waterfowl was mandated. But if you were not a waterfowler, perhaps you missed it.

    Anyway, bald eagles also feed on wounded waterfowl, and it does not take many lead pellets to poison them. (I’ve seen the autopsy photos.)

    Your local wildlife-management professor or state wildlife biologist may have the scientific papers that you seek.

  7. JD says:

    Complete BS!!!
    Why isn’t there dead wildlife laying all over/near gun ranges if lead shot kills them? This is nothing but a group of anti-hunters/gunners trying to drive up the cost of ammo so people give up the sport due to cost.
    I sure as hell couldn’t afford to hunt/shoot as much if I had to use copper bullets, $$$.

  8. Sebastian says:

    I was in elementary school in the 80s when this debate was going on, so I missed it.

  9. JD says:

    Chas Clifton Said,
    January 26th, 2010 at 10:32
    “(I’ve seen the autopsy photos.)”

    Well than proves it then!
    Gee, someone with an agenda couldn’t have some phony photos, could they? PUHLEASE.

  10. JD says:

    Sebastian Said,
    January 26th, 2010 at 11:03 pm
    “I was in elementary school in the 80s”

    Me too, remember that we were told how “bad” eggs and beef were for us back then? Not so much today. Thats what these anti-lead zealots are trying to do now.

  11. Sebastian says:

    I actually don’t dispute that lead toxicity can happen in birds. There’s plenty of studies out there that show high mortality if you feed birds more than a certain number of lead pellets. The question is how often this happens, and if it’s enough to destabilize the populations.

  12. ParatrooperJJ says:

    Jeff – On the contrary, only migratory birds require the use of non lead shot when hunting. I went hunting this past weekend for quail and pheasant with lead shot and it worked quite well. Just as a side note lead is far superior to steel or other alloy shot in effectiveness in downing birds.