Acadia National ParkPage 204 of 275
Peregrine Falcons at Acadia’s Precipice in 2022: Two Chicks and a Conservation Comeback
In 1988 a peregrine falcon that had been released from Acadia National Park's Jordan cliffs two years earlier turned up at the Precipice cliffs. His first two tries at breeding failed because his mates were too young, and his third nest failed in a brutal spring storm. In 1991, on his fourth return, he raised what the park's 2022 raptor intern calls the first wild falcons on the east coast since the 1950s. In 2022 peregrines nested on the Precipice for the 31st year, with only three failed nests in all, and the park's falcon watch has run for every one of those years. This account follows the 2022 season, written week by week by the Student Conservation Association raptor intern.
Why the birds had vanished
The intern explains that the insecticide DDT, introduced in the 1950s and 60s, was first used to kill mosquitoes and became infamous for its harm to the environment, and peregrines were hit particularly hard. DDT bioaccumulated: it worked its way up the food chain, so the smaller birds peregrines eat were full of DDT from eating insects. In the intern's account it caused a calcium deficiency, so the eggs were weak and broke and fewer chicks hatched, until there were virtually no peregrines east of the Mississippi. DDT was banned in 1972, but the falcons were gone.
Acadia answered in the early 1980s with a program called hacking, run alongside falconers, which raised young falcons and released them on the Jordan cliffs, near the Jordan Pond House. About 20 birds were released each breeding season in the hope that at least one would imprint on the cliff and come back to nest when mature. The program ran for a few years until 1988, when a falcon hacked in 1986 appeared at the Precipice, the bird named Ganesh, meaning “The Chosen One”.
The 2022 season
The first falcon of the year was seen around the Precipice at the end of February, a pair later scouted a nest site and the Precipice Trail was closed. The chicks were first seen in mid-May. The intern's count: over 150 chicks have fledged from the park, and in 2022 the hope was to add nine more, two at the Precipice, four at Jordan Cliffs and three at Valley Cove.
| Week | What the intern recorded |
|---|---|
| June 15–17 | The falcon watch program began on Wednesday, with over 300 visitors. Two chicks were about 30 days old by Friday; chicks typically fledge 35 to 42 days after hatching. The adult female chased off a mature bald eagle |
| June 19–25 | On Tuesday the chicks left the scrape for a nearby ledge for the first documented time, and early on Friday both fledged. That both fledged the same day was odd, since one chick is usually slightly younger. Parents drove off a turkey vulture and a herring gull |
| June 26–July 2 | The fledglings, named Bartlett and Comice after pears (peregrines, “PERE-grine”), spent every day together. They dived for the first time on Wednesday and later chased dragonflies as practice for catching birds. The intern's best guess from their size was that both are males |
| July 3–9 | Flights grew longer, though the young still could not catch their own food. One flew about 40 feet overhead, showing the vertical tan bars of juvenile plumage |
| July 10–16 | The young chased off an immature bald eagle for the first time and dived at gulls and insects, while the parents were seen less and less |
| July 17–23 | On Monday a fledgling flew in with its own food. On Friday all four birds flew together, the second family flight of the year |
| July 24–30 | As of Monday the birds were 68 days old. By Thursday they were gone, to explore the world until they mature at around age 2 |
Heat and fog often hid the birds: the cliff can be 15 to 20 degrees hotter than the ground, and the falcons sought shade. A digital media team used an 800 mm camera with a 2-times teleconverter, a 1600 mm zoom, linked to a monitor so that a large group could watch at once.
What the watch taught visitors
- No nest. Peregrines scrape dirt and gravel on a ledge, so the eggs on the Precipice lie on bare gravel 600 feet up the cliff; that is why the site is called a “scrape”.
- Speed. The intern writes that peregrines are the fastest animal in the world, diving at up to 200 miles per hour, and that the fastest recorded in a controlled study dove at 247.
- Size. Females are around 30 percent larger than males, and the birds are full grown by the time they leave the nest.
- Diet and plumage. They eat mainly other birds. Young birds have vertical tan bars on white chests; as they mature they gain darker facial feathers and a yellow lore, and the stripes turn into horizontal grey ones.
- Telling them from turkey vultures. Falcons flap little and soar on thermals, stay close to the cliff and rarely circle tightly, are about the size of a crow with “M”-shaped wings and a white chest in good light, and dive with their wings tucked in.
Sources
- Student Conservation Association Raptor Intern at Acadia National Park, View From the Aerie: Peregrine Falcon Watch in 2022, National Park Service; fully paraphrased, photos left out; rewritten in hubnx's own words.