Are They The Good Guys Or The Bad Guys?
(This is a 2019 update of Interim and Random Musings in Wolverine Café, July 8, 2005)
Golden eagles once flourished in Ireland, particularly in Donegal and Antrim counties, and along the western coastal regions. But from habitat changes and extensive hunting, golden eagles became extinct in Ireland by 1912. The eagles were popular targets for shooting parties on large estates in the 19th Century. Stuffed specimens were fashionable as estate house decorations, and eagle eggs were prized by collectors.
Fortunately, golden eagles have been successfully reintroduced to Ireland. Eagles trapped in Scotland and elsewhere in Europe have been moved to Ireland. In May, a pair of golden eagles nested and laid an egg – believed to be the first Irish born eagle in nearly 100 years.
Ironically, golden eagles might be causing the extinction of another species, on the other side of the globe. The Santa Cruz fox is a dwarf-like fox weighing only five pounds. It lives only on the Channel Islands off the California coast.
Until a decade or so ago, these little guys prospered on the islands. But the numbers have declined dramatically – from 8,000 or so in the 1980s, to 1,500 or so in 1994 to about 80 now.
The “why” shows how interconnected the ecosystem is.
Bald eagles used to be at the top of the food chain on these islands. These eagles lived on fish, seal carcasses, and fish-eating birds like sea gulls. Bald eagles ignored the foxes. Bald eagles were also territorial and discouraged golden eagles from moving into the islands.
But bald eagles began to disappear nationally in the 1950s, due to the widespread use of DDT. DDT is now banned, and the bald eagle population is growing nationally. But not on the Channel Islands. The largest manufacturer of DDT in the pre-ban era dumped its pesticide-laced wastewater into the Los Angeles sewer system, and tons of contaminated sediment still lies on the ocean floor near the Channel Islands. Bald eagles vanished from the islands by 1960, and they have yet to come back.
It took the golden eagles a couple of decades to realize that the bald eagles no longer guarded the Channel Islands. The golden eagles moved in during the 1980s, and soon learned that the little Santa Cruz foxes were good eating and easy hunting.
Biologists are trying to reintroduce bald eagles to the Channel Islands. They are also attempting to trap and relocate golden eagles to the mainland. All of this may or may not be successful in time for the foxes to survive.
The lesson here is that there are two ways to maintain the delicate balance of the ecosystem.
One way is to leave everything alone and let nature take care of the balancing.
The other way is to fill the ocean floor around Southern California with pesticides, shoot and stuff golden eagles in Ireland, capture golden eagles in the California Channel Islands and transport them to Ireland.
2019 Update
The reintroduction of golden eagles to Ireland may not be working out as well as everyone hoped. The Donegal gold eagles are starving and at risk of extinction, per a 2015 article in Irish Times. The program remains closely monitored by Irish biologists.