Friday, October 27, 2017

Hunting Lead-Free

With firearm deer hunting season getting ready to start in many places in the midwest, it seemed like a good time to remind people to hunt lead-free. Our director John Howe does so, and so do many of my friends, most of whom are concerned about lead's impact on wildlife and on themselves. Ingesting lead ammunition kills Bald Eagles and other birds of prey: ingesting lead fishing tackle kills loons and other waterbirds. Lead poisoning has been documented in 63 species of birds since 1939, including eagles, ravens, pheasants and other game birds, owls, rails, gulls, buzzards, kites, vultures, condors, falcons, red-tailed hawks, white-throated sparrows, yellow-rumped warblers, and solitary vireos. If you hunt, do wildlife and your family a favor and switch to non-toxic ammo.


This video about the issue features Kay Neumann from SOAR

I've compiled some information about wildlife exposure to lead. If you are looking for places to purchase non-toxic ammo, follow this link to our website: https://www.raptorresource.org/learning-tools/hunt-and-fish-lead-free/ or check out SOAR's excellent resources: http://soarraptors.org/hunt-and-fish-lead-free/. If you aren't familiar with non-toxic shooting, check out this Tom Roster's 2016 non-toxic shot lethality table: https://gf.nd.gov/gnf/hunting/docs/tom-roster-nontoxic-shot-lethality-table.pdf.

Is lead really a problem? 
Absolutely. Lead is a toxic metal with no known safe exposure levels for humans or wildlife. In the United States, an estimated 3,000 tons of lead are shot into the environment by hunting every year, another 80,000 tons are released at shooting ranges, and 4,000 tons are lost in ponds and streams as fishing lures and sinkers. As many as 20 million birds and other animals die each year from subsequent lead poisoning (yes, this shocked me, but I verified it with the source (http://bit.ly/2d7h7KJ and http://bit.ly/2e0eYXs).

Lead is a big killer of Bald eagles. From 1975 to 2013, the National Wildlife Health Center conducted a mortality study on the carcasses of 2, 980 Bald Eagles and 1,427 Golden Eagles. Their summary looked like this:

Cause of deathBald eagleGolden eagleTotal
Drowned11 (0.4%)3 (0.2%)14 (0.3%)
Electrocution 372 (12.5%)381 (26.7%)753 (17.1%)
Emaciation176 (5.9%)90 (6.3%)266 (6.0%)
Disease155 (5.2%)39 (2.7%)194 (4.4%)
Poisoned762 (25.6%)117 (8.2%)879 (19.9%)
Shot 303 (10.2%)196 (13.7%)499 (11.3%)
Trapped59 (2.0%)39 (2.7%)98 (2.2%)
Trauma 681 (22.9%)84 (26.9%)1,065 (24.2%)
Undetermined 298 (10.0%)131 (9.2%)429 (9.7%)
Total 2,9801,4274,407

The study found that 63% of the poisoned bald eagles and 58% of the poisoned golden eagles had been killed by lead, which was the second-biggest killer of bald eagles. Note that the study did not look at whether lead was a factor in trauma deaths (the biggest killer of eagles if poisoning is broken into lead poisoning and everything else). However, other studies have found that sub-lethal amounts of lead play a large role in eagle collisions. Lead is an even bigger killer of eagles than this study indicates.

How are birds and other animals exposed to lead?
They eat it. Fish-eating birds like bald eagles and loons eat fish that have ingested lead sinkers or other tackle, while scavenging birds like bald eagles, vultures, condors, and some hawks feed on gutpiles left by hunters that contain fragments of lead ammo. They also eat the carcasses of animals that weren't recovered and eventually died of their wounds. Waterbirds like trumpeter swans, mallard ducks, and loons ingest ammunition or lead sinkers while foraging in lakes, and upland birds like pheasants mistake shot for seeds or grit and eat it.

If I switch to non-toxic ammo, will it really make a difference? 
Absolutely! Switching to non-toxic ammo will prevent lead from entering the environment, which will keep it out of the bodies of birds, animals, and people that enjoy eating wild game. Here's an example: In 1991, the U.S. Fish and Wildlife Service outlawed the use of lead ammunition to hunt migratory waterfowl after it was estimated that 2 million ducks died annually from ingesting lead pellets. A follow-up survey of ducks on the Mississippi Flyway found that the ban on lead shot reduced lead poisoning deaths of Mississippi Flyway mallards by 64 percent, while overall ingestion of toxic pellets declined by 78 percent over previous levels. By significantly reducing lead shot ingestion in waterfowl, the ban prevented the lead poisoning deaths of approximately 1.4 million ducks in the 1997 fall flight of 90 million ducks. Plenty of ducks were still harvested, but far fewer died accidentally after ingesting lead.

Does non-toxic ammo and fishing tackle actually work? 
No one wants to switch to ammo or tackle that doesn't work, but non-toxics work very well! Let's start with wildfowl. The total number of migratory waterfowl harvested nationwide declined steeply beginning in about 1984, but started rising again after the ban on lead ammo was enacted, as shown by the chart. Requiring the use of non-toxic shot did not negatively impact waterfowl hunting, but did prevent ducks, geese, and many other animals from coming into contact with lead shot by ingesting it directly or feeding on lead-poisoned animals or carcasses containing shot. How about doves? A multi-year study by the Texas Parks and Wildlife Department found no statistical difference between lead and steel ammunition in terms of doves hit, missed, crippled, and killed at all ranges. How about other game, including deer? A large study done in Germany found that lead-free rifle bullets were as effective at killing wildlife as conventional lead bullets. How about deer and only deer? This article in Whitetails, the magazine of the Minnesota Deer Hunters Association, discusses non-toxic ammo with eight hunters that made the switch.

Saving Our Avian Resources has done a lot of advocacy for non-toxic shot and they have wonderful information on their website. A few figures that struck me:
  • A study of causes of mortality in eagles submitted to the National Wildlife Health Center between 1975 and 2013 found that trauma and poisonings (including lead poisoning) were the leading causes of death for bald eagles throughout the study period.
  • 56% of all eagles admitted to Iowa rehabilitators between 2004 and 2008 had abnormal lead levels in their blood. This ranged from a low of 37.5% in 2004 (with 62.5% of eagles being tested) to a high of 70.0% in 2005 (with 90.0% being tested).
  • The University of Minnesota’s Raptor Center in St. Paul received 117 lead-poisoned bald eagles during the winter of 2009. In 2012, Dr. Pat Redig co-authored this paper about spent ammunition and lead poisoning in bald eagles.
  • In Canada and the USA, approximately 10–15% of recorded post-fledging mortality in Bald and Golden Eagles was attributed to the ingestion of lead shot from prey animals (Scheuhammer and Norris 1996). Elliott et al. (1992) found that 14% of 294 sick, injured. or dead Bald Eagles in British Columbia (1988 to 1991) were lead-poisoned and an additional 23% sub-clinically exposed.
  • A 2012 study by a team at the University of California at Santa Cruz found that 30 percent of blood samples taken from condors each year showed levels of lead high enough to cause significant health problems and that 20 percent of the free-flying birds required treatment to remove lead. From 1992 to 2012, the cause of death was established for 123 condors in California, Arizona and Baja California, Mexico; lead was responsible for 42 of the mortalities (https://goo.gl/fmK8Ku). While lead poisoning can kill directly, lead toxicity is also a factor in collision deaths and injuries. According to the Raptor Center, about 85% of eagles that come in with collision injuries also have elevated lead levels. 
The best time to switch to lead is now! Good luck with your lead-free hunts this year!

References

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