By John Upton
A hunk of potato planted in a field sprouts into a leafy plant. A potato swells in the soil beneath the low canopy, fostered by water, fertilizer and pesticide, before it is torn out by a tractor and scrubbed and sliced by machine. A sliver of it tumbles into a plastic bag that is filled, sealed, frozen and trucked to a downtown fast food store.
The French fry is boiled in oil and lands in the bottom of a cardboard holster. The customer’s gluttony is satiated before his super value meal is done and the chip lands near a trash can, spinning in a waterfall of leftovers and packaging. It is grabbed by a rock pigeon which, hours later, is snatched up by a Peregrine falcon and fed to fledglings in a nest on an office building’s roof.
Peregrine falcons were nearly wiped out in the United States by the 1970s, their shells made fatally fragile by DDT sprayed to keep mosquitoes at bay. The poison bioaccumulated in the food chain and became concentrated in the falcons. The remarkably large raptors recovered spectacularly after the chemical was banned and American Peregrine falcons were removed from lists of endangered species in the 1990s.
As the populations recover, they have mastered the city environment, nesting on buildings and bridges. By preying heavily on the ubiquitous pigeons that eat our voluminous waste, they have established a food chain that runs from farm to trash to scavenger to urban predator.
But new and old threats nag at these birds all around the world.
Old: Falconers steal chicks from nests to be reared as hunters (and, increasingly, for lucrative commercial purposes – landfills hire falconers to scare away seagulls).
New: Toxic flame retardants used in furniture seep as dust into the environment and have been discovered bioaccumulating at high levels in Peregrine eggs.
The flame retardant threat is pronounced in California, where a strict law based on outdated science mandates the use of such chemicals at certain levels. Last week, Gov. Jerry Brown ordered a review of the 37-year old law in a bid to protect human health and wildlife. The review, by the California Bureau of Electronic and Appliance Repair, Home Furnishings and Thermal Insulation, is expected to establish a new industry standard that will be adopted as law by other governments.
The threat of poaching, meanwhile, is as established as the milleniums-old sport of falconry. To help curb that threat, scientists often try to keep vulnerable locations of nesting falcons a secret.
Here is a video from YouTube of commercial falconer Steve Vasconcellos keeping gulls away from a dump at Half Moon Bay, California. Vasconcellos was in talks with the San Francisco Giants to scare seagulls away from the waterfront ballpark, but the franchise’s operations manager recently told me the team had balked at the price tag, which I understand would have been well over $100,000 a year.