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Posts categorized Summerhill Preserve.

Summerhill Preserve Kestrels 2015

American Kestrels in the nest box

American Kestrels in nest box
(photo – Ron Zigler)

By Mike Coll Preserve Manager

For the second straight year, the nest box at our Summerhill Preserve successfully fledged American Kestrels. This year there were four young.

This video shows one of the adult birds flying up to the box to feed the young (in slow motion):

Here you can see the young birds inside the box. They fledged from the nest less than a week after this video was taken:

Read more about our nest box installation at Summerhill Preserve (one of our nature preserves open by appointment) and the Kestrel population there in this June, 2014 blog entry.

Kestrels at Summerhill Preserve

A new Kestrel nest box at the Summerhill Preserve successfully attracted it’s target species in the first year.   The box was mounted on a natural cedar post by FON volunteer Brian Bernero.  Installed, the opening of the box sits approximately 14 feet above the ground in a warm-season grass meadow.  I wrapped metal flashing around the post to prevent predators from climbing up into the box.


A pair of Kestrels found the box almost immediately in early April.  I observed the male sitting on the box with the female in a nearby tree.

A few weeks later towards the end of May I reached a camera on the end of a pole into the box and took this picture.

The fact that the female (pictured) did not leave the box when I approached it told me that she was likely incubating eggs.

A few weeks later on 6/12 I returned to take this picture showing some newly hatched falcons, probably 7-10 days old.


This week (on 6/25) I returned again to the box.  As I approached I could see the head of one of the young birds poking out of the hole.


Less than 30 days after hatching, young Kestrels weigh as much as their parents.   These 5 fledglings have grown most of their flight feathers and are nearly ready to leave the box.  Once they leave the nest their parents will continue to feed them for a number of weeks as they learn how to fly and become effective hunters.  All of them must race to become self sufficient before the fall when they will most likely attempt their first migration.

Hildacy Farm Preserve: Nest box work

By Michael Coll, Hildacy Farm Preserve Manager

As April approaches, it is the last chance to prepare nest boxes for the return of migrant species.  Throughout the next few months, breeding pairs will be searching for nesting locations and attention to detail within each nest box installation can be the difference between successfully attracting the target species and simply placing a wooden box in the landscape.

The first new box that I put up this year was a Wood Duck box near the restored wetlands at Hildacy Preserve.  The box was well constructed by a volunteer and on the opening now sits more than 8 feet off the ground.  I have used two wraps of metal flashing around the wooden post to hopefully prevent intrusion into the box by nesting squirrels and potential predators.


My choice of location for this box was motivated by two separate ideas.  The first is as a potential nest spot for Wood Ducks.  Each year around this time I observe a few Wood Ducks visiting the wetlands (in fact there is a pair there now as I write this).  The birds are present for a few days or weeks, most likely feeding on the abundant plant life and insects in the wetlands, and then go somewhere else for the bulk of the breeding season.  I suspect these wetlands might be just a bit too busy for Wood Ducks to feel secure.  Different species are affected differently by the presence of humans and Wood Ducks tend to prefer a more secluded setting than, say, Mallards, which often don’t seem bothered by people at all.  However, it is also possible that these passing ducks haven’t stayed because there were no suitable cavities in which to nest.  If this is the case then perhaps they will make use of this new box.  I placed it as far from the main walking paths as the area allowed.  The placement was also determined by the idea that it could be easily observed.  I have put other Wood Duck boxes up in considerably more secluded locations on Hildacy and in fact these locations are so secluded that I have not properly monitored them and so I do not know if they have been used!

The second purpose for this box is as a possible secondary home for my resident Screech Owl.


I have read that breeding Screech Owls will sometimes seek out secondary roosts near their nest sites.  Perhaps when a small box becomes full of young fledgling owls it is nice to have somewhere nearby for the adults to sleep.  Because Screech Owls will sometimes use Wood Duck-sized boxes, I thought that placing this new box in a direct line of sight with the existing owl box could possibly serve that purpose (assuming it is not occupied by Wood Ducks).

For the past two years, a Screech Owl has roosted throughout the winter in a box about 100 yards away.  I have a working camera in the box and, as I write this, he (I believe it’s a male) is sleeping the day away inside.


Each spring when breeding season arrives for Screech Owls, I have heard the male calling from the opening of the box, but I have never observed a mate.  A few weeks later, the owl leaves the box (presumably to breed somewhere else) and doesn’t return until the fall. I hope that this year the presence of a secondary roosting spot will change this pattern and convince a pair to nest.

Another project that I crossed off my list recently was to increase the height of my bat box. Originally this large, heavy (sail like) box was attached to a 12’x4”x4” post that was set into the ground with cement.


With a few feet of the post buried in the ground, the opening of the box (which is on the bottom) was barely more than 7’ high. The recommended height for bat boxes is no less than 10’ and higher is preferable. I had hoped that placing it on a slope would help to make up for this, but after seeing it go vacant last year I decided to cut the existing post and add a second 12’ post, attached by carriage bolts at the top and bottom. This addition raises the opening of the box to over 13’.


Hopefully, this will make the box more attractive to bats since its current location hits nearly all of the other recommendations for placement including: distance from trees (25 ft), proximity to water (stream and wetlands), good sun exposure, and south facing in an area where bats are regularly observed.

Last year was a banner year for Kestrels at Natural Lands Trust’s preserves with nesting pairs in boxes at both Gwynedd Wildlife and Hildacy Farm Preserves.  I am hopeful that the Kestrel box at Hildacy will soon be inhabited again by these small, brightly colored falcons.


In that aim I have cleaned the box that was used last year (including scraping the interior walls, which the fledglings seemed to have painted white!) and replacing the bedding with new wood chips.

In addition I have added another Kestrel box at our Summerhill Preserve. I have previously observed breeding Kestrels on this preserve (I saw fledgling birds but never found the nest site). However, last year–possibly due to a nearby “forest cleanup” that removed some old standing dead trees–I did not see any young birds. It seems likely that the pair’s nesting cavity was destroyed, which makes Summerhill an ideal location for a box. With any luck, the pair will find the box and breed successfully in the next few months.


The box was constructed by Force Of Nature volunteer Brian Bernero, who mounted it on a natural cedar post. To extend the length of the natural post we bolted it to a mostly buried 4”x4” making the final height of the box’s opening more than 12’ off the ground. Metal flashing was again used as a predator deterrent. The box faces south and is in a warm-season grass meadow that is rich with prey and removed from human disturbance.


The last of the nest box preparations were performed by other members of our Force Of Nature team who have cleaned out all of the 44 Eastern Bluebird boxes at Hildacy and Summerhill. While many of these boxes are used each year by Tree Swallows, Chickadees, and House Wrens, bluebirds continue to find boxes to nest in as well. Last year, volunteer monitors reported seven successful bluebird nests at the two preserves yielding 31 fledglings. This year, I will change the location of the boxes that were dominated by House Wrens in an effort to discourage them. I will also be continually mowing small areas around some of boxes that are in the warm-season grasses. It is possible that by keeping the grass height lower, more bluebirds will return to attempt a second brood. (Download our guide to Eastern Bluebird nest boxes here.)

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Summerhill Preserve Tour – White Oak Society and Allston Jenkins Legacy Society members only

Wednesday, May 2
10:00 am – 1:00 pm
Summerhill Preserve, Willistown Township, PA

Join us for a springtime walk at our 41-acre Summerhill Preserve. Roger Latham, Ph.D., Ecologist/Conservation Biologist and Natural Lands Trust Board Member, and Michael Coll, Summerhill Preserve Manager, will lead our walk. We’ll learn about the intricacies of establishing native meadows and be on the lookout for the many birds that frequent the preserve’s woodlands. One of the more recent additions to our preserve system, Summerhill was the gift of Martha Stengel Miller and is only open for guided tours. Refreshments will be provided by preserve neighbor and NLT board member Keith Pension. We’ll also be joined by Rusty Miller and Ken Nimblett, NLT President’s Council members, who have played a pivotal role in helping to preserve this special family property.

Click to learn more about the White Oak Society and Allston Jenkins Legacy Society.

Space is limited to 30 guests. Please RSVP to Suzanne Barton 610.353.5640 ext 313, .

Guided Bird Walks at Hildacy Farm Preserve and Summerhill Preserve

Thursdays, April 26 – June 14
8:00 AM – 10:30 AM
Hildacy Farm Preserve, Media, PA and Summerhill Preserve, Willistown Township, PA

Hildacy Farm and Summerhill Preserves contain a mix of habitats that attract diverse wildlife – particularly birds. Preserve Manager Mike Coll will guide you on an exploration of wetlands, woodlands, and native grass meadows that are home to Indigo Buntings, Red-shouldered Hawks, Baltimore Orioles, and many more species. New birders are welcome and encouraged.

Be sure to wear sturdy walking shoes and dress for the weather. Walks will proceed in inclement weather but will be cancelled if there is a downpour. All walks meet in the parking lot of Hildacy Farm Preserve.

All walks are free and open to the public. No preregistration required.


5/17 Hildacy Preserve

5/24 Ridley Creek State Park “Bridal trail”

5/30 Hildacy Preserve (CHANGED FROM MAY 31ST)

6/7   Summerhill/ Mill Hollow Preserve

6/14 Hildacy Preserve

Work Party: Invasive Plant Removal at Summerhill Preserve

Sunday, June 16
9:00 AM – 1:00 PM
Summerhill Preserve, Willistown Township, PA

Invasive plant species present an enormous challenge to Natural Lands Trust’s goal of maintaining healthy and diverse habitats. Invasive species quickly spread and outcompete native species. One way that Natural Lands Trust answers this challenge is by manually removing invasive species … and we need your help! Join Preserve Manager Mike Coll to learn how to identify and remove common invasive plants. Families and groups are welcome.

Breakfast, snacks, lunch, and water provided. Please wear sturdy shoes or boots and bring your water bottle, work gloves, and a raincoat if needed.

This event is free but registration is required. For individual and family registration, click here. For group preregistration, please contact Angela at or (610) 353-5587, ext 266.


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