Animal conservationists frequently attach GPS tracking tags to animals to better understand their lifestyles and movement patterns, and Yellowstone National Park’s prestigious golden eagle (Aquila chrysaetos) was no exception to that. Unfortunately, it wasn’t long after tagging a few of the birds that something went terribly wrong…
Image Credit: National Park Service via The Guardian
As it would seem, the very first of a small number of Yellowstone’s golden eagles to be tagged has unexpectedly died from lead poisoning after leaving the park’s protected boundaries and ingesting lead ammunition fragments left behind in the carcass of a hunter’s game. The findings came to light after researchers performed a necropsy on the deceased bird.
“This bird had a substantial amount of lead put into its system in a very quick way,” U.S. Geological Survey biologist Todd Katzner told The Guardian in a statement. “You don’t get that from breathing lead. It ingested something.”
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Perhaps unsurprisingly, the circumstances have raised a bevy of previously-expressed concerns regarding the safety of protected parks for the animals that inhabit them and the use of lead-based ammunition for hunting rather than safer alternatives like that of copper-based ammunition.
Unlike people, who define protected parks’ boundaries and determine where hunting is legal and where it’s not, Yellowstone’s golden eagle doesn’t know where the said areas start and end. It’s not uncommon for the birds to leave the park in search of food before returning home, and so it can be inferred that even the park’s surroundings pose a threat to its wildlife.
“We know that lead poisoning is a substantial threat to scavenging birds of prey globally,” Katzner added. “And we now know the threat is extended to birds that are in protected areas such as Yellowstone.”
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Lead-based ammunition is popular among hunters because it’s cheaper than copper-based alternatives. On the other hand, it’s not as environmentally-friendly as the latter. Environmentally-conscious hunters will sometimes bury gut piles that have been exposed to lead ammunition in an effort to prevent birds such as the golden eagle from eating it, but as shown in this case, not all hunters partake in this practice.
Yellowstone’s golden eagle isn’t in any imminent danger of extinction, but conservationists are keeping a firm eye on the species to learn why Northern park populations are reproducing more effectively than Southern park populations. The GPS tracking devices were one of the first steps taken in the effort to study the species.
Conservationists attached the tracking device to the first (now deceased) golden eagle back in August 2018 and followed up at the start of 2019 by tagging five more specimens. Although the first bird is no longer flying around and providing a live GPS data feed, the scientists managed to capture a moderate dataset chunk from the specimen over the last eight months.
It remains to be seen how the lead-based ammunition situation will be handled, but it certainly is unfortunate that the park’s very first GPS-tagged golden eagle had to die this way. What are the odds?
Source: The Guardian
