2018 Tree Swallow Nest Box Report
Fresh Pond Reservation

 Tree Swallow Nesting Box Replacement Project

Friends of Fresh Pond Reservation and the Cambridge Water Department
January – March  2018
During the winter of 2017-18, a Fresh Pond neighbor offered to make a donation of $750 to the Friends group for a project to benefit the Reservation. We suggested that the money be used to replace some or all of the ageing nesting boxes that were built by the Friends group and the Cambridge Water Department in 2004 and 2008. The donor agreed.
We decided to buy commercially made nesting boxes, rather than take on the labor-intensive job of making the boxes ourselves. Our first purchase was a cedar wood duck box from Etsy, to be placed on a post in Black’s Nook. On February 28, Reservation Manager Vince Falcione and Ranger Tim Puopolo set up the box on a post in the water on the north side of the Nook.
I used the remaining money to purchase fourteen of Duncraft’s “Bird-Safe ® Swallow Nest Boxes,” Item #4578. These handsome boxes have sides, backs, and bottoms made of white pine, and tops and fronts made of a durable green synthetic material. All pieces are securely screwed together, as opposed to nailed (observed in some less expensive boxes.) The entry opening is a long slit along the top of the front, a very different design from the familiar round hole. Our home-made boxes had 1 1/8 inch holes, the smallest recommended opening that would allow access by tree swallows but prevent entry by house sparrows.  Nonetheless, each year, some of our boxes were taken over by house sparrows, whose population has increased enormously in recent years. The opening on the new boxes is said to prevent house sparrows from gaining access. Each of the new boxes has a coated wire grid attached on the inside below the opening to make it easier for the young birds to climb out when they are ready to fledge. These new boxes are mounted on the three quarter-inch threaded metal pipes that were used for the old boxes: I drilled holes so that a threaded pipe flange could be attached to the bottom of each box, using bolts, nuts, and lock washers.
We decided to make new hardware cloth predator guards rather than reuse the ones on the old boxes.  The original guards have been badly bent and damaged during years of transport and storage. I devised a system that allows the new guards to be easily slipped onto the pipes when the boxes are put up in the spring, and easily removed from the pipes and stored separately during the winter.  Ranger Jean Rogers cut the quarter-inch hardware cloth into 2-foot squares with a 1-inch hole in the middle, and I used wire to attach under each hole, a ring made from a Ball jar lid.  I then attached below each ring a sleeve collar with a thumb screw for tightening it. I glued the collars onto the rings with metal epoxy…….The guards can be slipped onto the pipe from the bottom and tightened directly under the boxes with the thumb screw.
Each year since we started the nesting box program we have designed and printed a map showing that year’s locations of boxes, not only for tree swallows but also for chickadees and screech owls. This year I redid the numbering system on the map for the swallow boxes: the order had gotten scrambled over the years as we tried boxes in different locations. The numbering will once again be sequential going clockwise around the reservoir, with Box #1 located in front of the water treatment plant near the water.
For numbering the boxes, I bought number stencils and black latex paint.  I painted numbers on both sides of each box.  I also chose two old boxes that are in good condition and painted numbers on them: #13 for a box in the Woodland Habitat Restoration Project, and #16 for a box in the newly created bio-swale on the east side of Fresh Pond.
I delivered all of the numbered boxes and predator guards to Vince on Friday March 23. Vince put them up on Monday, April 2, observing that the tree swallows had already begun to show up on the Reservation.
Elizabeth Wylde
April 4, 2018.
NOTE: A report on the success of this year's project will be written after the nesting season is over and the boxes are taken down in late summer or fall..