Peregrine Watch Update Archive - 2011

Each week of the Peregrine Watch in 2011, Raptor Intern Delora Hilleary shared information about the park's peregrine falcons in the update called the View from the Aerie. The Peregrine Watch was terminated early this year due to the failure of the birds' nesting attempt at the Precipice. See below for Delora's weekly updates on the status of the nesting attempts of the park's peregrine pairs.

April 27 | June 1 | June 8 | June 17 | June 30 | July 7

Peregrine sketch

Female peregrine falcon from Beech Cliff, perching and in flight.

Sketch by Delora Hilleary

Peregrine Watch is finished for the season.

July 7, 2011. When I think of the word "falcon," the image that is summoned to my mind is one of power, agility, and above all else - speed. These birds are spectacularly adapted to be perfectly aerodynamic, and to rule the skies as a top avian predator. A peregrine's well-developed eyes can see about eight times better than a human, and they use their eyes to lock onto smaller birds, their targeted prey. As a peregrine positions itself to strike its prey in a stoop (or dive), its long, saber-shaped wings cut through the air like knives. A long tail serves as the rudder, allowing the falcon to twist and turn even at speeds up to 200 miles per hour. This species of bird is a master of flight, and a creature worthy of respect and protection.

Unfortunately, these speed demons cannot out run all that challenges their survival. Over the last several decades, peregrine falcons have come back from the brink of extinction in Maine with the help of reintroduction. However, their threats of endangerment have not been eliminated. Biologists and researchers at Acadia are baffled why at all nesting territories in the park failed in producing young this year when most parental behaviors looked promising. Guesses abound, from inexperienced parents to weather to chemical pollutants to competition. It is unfortunate that there are no peregrine chicks to observe in Acadia this year, but nature follows her own tempo and we can only hope this is a small blip in their overall recovery.

We cannot protect species from threats that we do not recognize or understand. Fortunately, Acadia National Park has several different cliffs that serve as prime nesting habitat for Peregrine falcons; individuals will try again and next year we will continue to observe, monitor, and document the activities of these fascinating falcons. We can only keep our fingers crossed and hope that there is success for the future, and to try our best as individuals to reduce pollution and stressors that may affect the birds.

With nesting failure and trails opening, the official Peregrine Watch ends early this season. Keep your eyes on the skies for adult peregrine falcons that may still be in the area, flying, swooping and stooping with incredible power, agility, and speed. Enjoy these masters of flight, and come mid-August, look for weekly updates again as we watch for migrating raptors heading south for the winter from up on top of Cadillac Mountain for Acadia's annual Hawk Watch.

-Delora Hilleary

Peregrine falcon sketch

Peregrine falcon female from Beech Cliff

Sketch by Delora Hilleary

June 30, 2011. Weather and fog shrouded the Precipice from view this week making observations a challenge. As I parked in the lot below the cliff in the early morning hours, I looked up to scan the cliff for movement and searched for signs of the daily soap opera that characterizes the Precipice falcon pair.

Much to my dismay, the parental behavior of the Precipice falcons dissipated this week as they appeared less often, and no longer took interest in avian or human intruders. Thus, the likelihood of chicks here dwindled, replacing our hopes for young with doubt and disappointment. Only two years in the last 21 years has the Precipice pair failed to produce young. The first time was in 2007 during a period of April Nor'easter storms. This year we're just not sure, leaving many with lots of questions. To learn the secrets of the falcons, the best thing I can do is the good 'ol scientific method-hypothesize, observe, document, monitor some more, observe until I go nuts, and then hope that the truth may be revealed. Of course, in science, there is always the possibility that a mystery remains a mystery. As I gaze upon the cliff site searching for signs of these amazing birds, I feel my time here is always worth it. Due to this year's apparent nesting failure, the Precipice Trail and Orange and Black Path are now open to visitors.

Meanwhile at Echo Lake, two Peregrines may be displaying nesting behavior on Beech Cliffs, visible from Echo Lake beach. I visited that area to get a look at the birds there and I was rewarded with a nice view of both of them. So I whipped out a notepad and sketched each bird, and noted the differences between them. The illustrations on this page are the first rough sketches I made while out in the field and I will use these sketches to make detailed illustrations of both birds so visitors can distinguish between the male and female. From these drawings one can tell that the Beech Cliff female is big and robust, with a salmon-pink tinge on her belly. The male is small and slender, with a clean white breast and very light barring. I am keeping my fingers crossed for this pair to be successful this year.

I am working on detailed sketches for the Precipice falcons, but the dynamics of the pair has made it a challenge to capture them in ink. Meanwhile, I'll continue to perch with my fellow rangers at the Precipice trail-head parking lot from 9am to 12pm every day (weather-permitting) as we continue to observe and document, at least for now. As failure is determined and the Precipice and Orange and Black Path opens it's important to remember that the Precipice is a non-technical cliff climb; it uses iron rung ladders to get you straight up the cliff face. This climb is not for the faint of heart, those with a fear of heights, or young children. Please remember good hiking shoes, plenty of water, and a trail map as well as other personal necessities. The best loop for this trail is to connect to the North Ridge Champlain trail at the top of the mountain and then to the Orange and Black Path to connect back to the Precipice parking lot. Please remember to be careful, and enjoy your adventure!

-Delora Hilleary

Delora Hilleary

Delora Hilleary scopes out the peregrine falcons at the Precipice

NPS/Laura Stevens

June 17, 2010. I began this week with the anticipation of a real adventure at the Precipice. It's banding time! Banding peregrine falcon chicks mark them as individuals for the rest of their lives. Color coordinated metal bands with letters and numbers attached around their legs allow researchers from all over to identify individuals with age and origin and track their movements and breeding activity. For example, we know that some of the chicks that hatched from Acadia National Park have nested in downtown Boston, New Hampshire, Vermont and New Brunswick, and traveling birds have been found in the Caribbean Islands and Washington, DC.

Exploring the falcon's world gives researchers a unique opportunity to get close to these birds, and it's an experience that one can get addicted to easily. I personally helped band various raptors and owls at the rehabilitation center I worked at, and I treasured every second that I had a bird in my hands. Looking into their eyes and feeling the power in their legs and wings - it is experiences like these that drove me to become a biologist myself. Thus, I volunteered my help to the technical team needed for the banding. The team included two technical rock climbers, a licensed bird bander, and Acadia's wildlife biologist and technicians. I hoped my previous experiences handling raptors would prove to be useful. Not to mention I really wanted to finally get a count of the number of chicks I had helped monitor at this site for three weeks now.

The day of the banding proved to have clear weather, so we arrived early at the Precipice trailhead and set off quickly on our hike. The Precipice Trail indeed held up to its reputation for being tiring, but as I climbed the cliff, I noticed that something was wrong. As the crew got closer and closer to the nest site, we expected angry falcon parents to come for us, screaming bloody murder. Despite our position right above the nest, no falcons came for us. It was eerily silent on the cliff side, since neither the parents nor chicks gave warning screeches. It was then that my anticipation turned into apprehension.

As the climbers anchored their ropes and prepared to descend into the nest site, I could see a small crowd of park employees and interested visitors gathered together to witness the excitement that usually surrounds a chick banding. I wondered if they were as apprehensive as I was, since there were no dive-bombing parents or territorial behavior at all. I didn't even see a parent, despite being right above the nest.

The climbers finally descended into the nest site to give us the moment of truth. I hovered with the radio, waiting for their report. The garbled voice over the radio confirmed my fears.

"No chicks."

There was a shallow depression in the nest site, but it was described as "immaculate." No feathers, no prey remains, no chick remains, no feces, no evidence of life at all. My devastation quickly turned into a barrage of questions. What had happened to the chicks? Was this really the site? Why didn't the parents attack us? Were there ever really chicks at all? Did pollution affect them?

The biologists and I were baffled at how clean the nest site was, despite there having been clear parental behavior for the past three weeks at the site. None of the falcon monitors have ever seen anything like this happen before. For me, this means that I need to do some more research into possible answers to the mystery.

There is still hope for the Beech Cliffs nesting pair. They continue to show promising parental behavior. As monitoring continues there I hope to participate in a banding session there, if their nesting attempt is successful.

I welcome visitors to come join me in further monitoring, and pondering explanations, of the quirky Precipice peregrine falcons from 9am-12pm every day, weather permitting. The Precipice Trail and Orange and Black Path remain closed to the public at this time. I may also appear at the Echo Lake beach to get a closer look at the Beech Cliffs pair, so stay tuned for next week's update.

-Delora Hilleary


June 8, 2011. Hello everyone, this is the new raptor intern writing! I am Delora Hilleary, and I am excited to join the rangers to witness this year's Peregrine Falcon Watch! I graduated in May with a major in Biology and a minor in Studio Art from Willamette University in Oregon, which is on the opposite side of the country, and I am looking forward to a future filled with birds and bird-related research. I also love illustration and hope that my drawing skills aid my scientific ventures. This is my first time in the Northeast, so in the coming months I will be happily exploring new territory and learning more of the biological diversity that America has to offer.

Though I am new to this area, I am no stranger to the power of raptors. I worked in a raptor rehabilitation center as a volunteer a few years ago, and I loved every second of it. Thus I am quite excited to witness the activity of these powerful birds in their natural habitat. As I traveled here and settled into my new residence, the persistent fog and cold weather in May stopped me from seeing very much falcon activity at the Precipice, so the presence and behavior of the falcons seemed to be veiled in rumors and mystery. However, this last week showed a great improvement in the weather and clarity in the skies, so I was able to finally see some consistent peregrine activity - and spectacular activity it was!

My first clear day of observing the Precipice was rewarded with the sight of the male swooping into the nest site with food. As of yet I cannot see the chicks, but the adult pair of falcons continues to show promising behavior such as prey exchanges and nest defense throughout the week. One of my favorite moments of the week was watching one of the falcons dive-bomb a large group of wandering turkey vultures. Though it was one against many, the turkey vultures stood no chance against the speedy parental falcon! Though these carrion-eaters do not pose much of a threat to either the living chicks or the adult falcons, the parents do not tolerate any creatures getting too close to the nesting area.

Despite the rigorous nest defense, there continues to be a particular individual invader that keeps returning. A third peregrine falcon still shows up to the cliff area to perch about, occasionally by the nest site. Since none of the adults appear to have bands on their legs this year, it is difficult to distinguish between individual falcons unless one sees them next to each other. Thus it is often hard to tell if I am looking at the invader or one of the parents when viewing a sitting falcon in the scope. I am working on sketching out the adult falcons while they are sitting still, so that perhaps I can tell them apart by individual characteristics in the future. As for now, I am not even sure yet if the invader is a male or a female, so I will certainly be looking closely in coming weeks.

As for the chicks, I hope to get a much closer look at them this coming week. Based on the parents’ behavior, it is estimated that the chicks hatched sometime around May 24th to May 26th. Thus, the time to band them is approaching! The possibility of seeing a fluffy little white head pop out of the nest site grows greater each day. Hopefully, I will have more on that next week.

Monitoring continues around the island, with interesting recent observations. The latest conclusions include active nesting at Beech Cliff and nesting failure at Valley Cove. Therefore, the Valley Cove trail is now open to hikers and Beech Cliff is now closed to technical climbing, but the trails remain open, as the trail is far enough from the nest that the birds are not disturbed or threatened by hikers. Please keep in mind that the Precipice Trail and Orange and Black Path remain closed for both visitor protection and nesting success as these trails go near the scrape site. For a chance at a closer look at some peregrines, I invite visitors to join me at the Precipice parking lot from 9am to 12pm. I'm definitely looking forward to a great season!

—Delora Hilleary


June 1, 2011. Another exciting season commences at the Precipice, as a pair of peregrine falcons continue to maintain a nesting territory on the steep east face of Champlain Mountain. Though the foggy, wet conditions of the past few weeks have hindered monitoring, slowly the pieces of a puzzle are being put together, and we have the hope that successful nesting continues at the Precipice. During the last week or so, when we can see the cliff, one particular ledge have been visited several times by the falcons, occassionally for longer periods of time, and we believe it is this year's nest site! Curiously, another pair used this same site in 1998.

Now that a scrape site has been identified, and the weather is improving, we are monitoring the site closely. We watch and record such behaviors as when an adult comes and goes to the site, if they bring prey (food) to the site, and any interactions between the male and female, as well as with other peregrines and other birds of prey (such as bald eagles). Behaviors that we would expect to see next include the female staying close to the nesting cliff and defending it from potential threats (primarily other raptors), the male hunting for food and bringing it to the scrape or close by for the female to take to the chicks, and potentially seeing puffy white downy chicks or hear them cry. The next couple of weeks could be very exciting!

Some unusual behaviors we've been witnessing at the Precipice involve the presence of a third peregrine, an apparent intruder. Aggressive behavior has been seen between the resident birds and this intruder, often with aerial chases and cliff-ledge defensive maneuvers with the resident bird flapping its wings to keep the dive-bombing intruder away.The resident female was even observed in the nest defending the eggs or chicks almost beak-to-beak with the intruder. As far as we know, this is the first time this close of an encounter has been seen at the Precipice. However, in the last few years competetive behavior has been seen here including an intruder male last year that was loitering around the site several times. In many other areas of the country, there are many stories of individuals fighting each other for the best nesting territory. In some cases a female has killed another to either maintain or gain a territory. As these peregrines are coming back from the brink of extinction and their numbers are increasing rapidly, competition is fierce and the Precipice is one of the best peregrine nesting sites in the state. These interactions have made observing these birds even more exciting.

At this time, The Precipice and Orange and Black trails remain closed, as is the Valley Cove trail on Somes Sound, since this pair on the west side appears successfully active. Peregrine activity has also been observed at Jordan Cliff (a single juvenile), Beech Cliffs, and Ironbound Island, however success can not yet be determined and no closures are necessary at this time. There's hardly a dull moment at the Precipice; come visit any morning between 9:00 and noon (weather permitting) to see what will happen next! See you there!


April 27, 2011. For more than twenty years now, a peregrine falcon pair has claimed this east-face cliff on Champlain Mountain as their home. This cliff is where the pair court, mate, nest, and raise their young together. A peregrine falcon pair has successfully accomplished this daunting task every year since 1991, with the exception of the year 2007. We hope that 2011 will be another productive year for the falcons and that after this spring and summer, up to four more chicks will be added to the fifty-eight chicks that have fledged from this cliff face since falcons were reintroduced into the park in the 1980's.

Acadia's biologists and other staff have already started monitoring this cliff, and we are encouraged that once again a pair of peregrines has started to defend "their" territory andcourt each other. These signs are the beginning stages of mating and producing young for this season. Their defense of the territory is much like us defending our own home, especially if young, or kids, are present. Their protection includes warning cries (a repetitive "kack-kack-kack-kack") for coming too close, flying around in circles to scare the threat away, and finally a "dive-bombing" attack with strong talons and speed to drive intruders out of the territory. "Intruders" include any presence that poses a possible threat—anything from a gull or a Bald Eagle to a person on the cliff. Because the peregrines are present and defending a nesting territory, the cliff and popular Precipice trail and Orange and Black path (formerly Champlain East-Face trail) are closed for their protection and to allow successful nesting as a Maine state endangered species. However, because these birds are so protective of their home and will attack intruders, the trail and climbing areas are also closed for visitor safety. Peregrine falcons are the fastest animal on earth, diving at speeds over 200 mph. One might not fare so well being trapped between this powerful, aggressive falcon and a sheer cliff face, so please respect this trail and climbing closure not only for the falcons' success, but also for your protection. For these same reasons, the Valley Cove trail has also been closed for peregrine falcon nesting and visitor protection.

Starting mid-May, rangers and volunteers will be at the Precipice parking lot to monitor the falcons and interpret this important resource of Acadia National Park. Please join us most mornings, weather permitting, between 9:00 am and noon to discover more about the natural history of these amazing birds and the history of this nesting site, and to learn about other resources of Acadia National Park.

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