Bluebird Business as Usual

It's a project that I'm all too familiar with. It was one of the first projects I got to help with when I first interned here last summer. And in terms of what to expect every time, this project falls into 1st place for being the most variable.

If you've been around the museum or Ongley Pond, you've most likely seen some of our bluebird boxes. The boxes are set up in a way to be both easily accessible to people and inaccessible to predators. These boxes are checked periodically at 2-3 week intervals. The interns and I go out to the boxes with a cordless drill and proceed to open them up one at a time. Our task is to then check the nest and write down all relevant data. This data includes bird species type, number of eggs/young, young status, and nest status.
White Memorial has been taking part in this statewide program since the 1990's. Coordinated by the Connecticut DEEP, the objective of the program is to restore the Bluebird populations that have been in decline for over 40 years. Species like the Bluebird and Tree Swallow are cavity-nesting songbirds that require preexisting cavities in their habitat in order to nest. By providing said habitats, we are able to give the birds safe areas to raise their young and thus help to bring their population back up. Besides this, we are able to use the nest box data for other purposes. For example, we can use the data to keep track of these bird populations throughout the season. We can see where each species type is hanging out and who's using which boxes. We can also get an idea of how many nestlings are surviving to adulthood.

House Wren nestlings in one of our boxes

Thankfully this project is one that interns can easily pick up on. It does take time to go to each box and record all relevant data. Though it isn't a particularly grueling task, the job isn't always a walk in the park. An outsider watching us work would probably find a couple reasons to laugh at us. The birds (especially Tree Swallows) are quite territorial around their young, meaning that they don't appreciate it when we come out to visit them. This means that we end up getting dive-bombed by birds on a regular basis. Don't worry. We get used to it. 

It's Time to Get the Songbird Nest Boxes Ready!

It's time to check those nest boxes to insure they are ready for this breeding season.  We'll be hosting a volunteer training for those people who would like to help us with monitoring all of the nest boxes on the property.  More information about the workshop will be posted soon, but take a look a the video in the meantime to see who makes them and how they are created.

Results of 2012 Bluebird Box Usage

Tree Swallow perched on Bluebird box

Female Bluebird
Photo by Bob Stanowski












In the beginning of August all Bluebird boxes on White Memorial property were opened, inspected, and cleaned out. Unfortunately Bluebirds had a difficult breeding season, resulting in a 41% success rate. Weather was mostly to blame for this low percentage. Bluebirds start to lay their eggs in mid-April; and as some recall in the beginning of May this year we had lots of rain with unseasonably cold weather. This combination of cold air with damp conditions proved to be too overwhelming for the eggs and chicks; this became evident when we discovered many dead chicks and abandoned eggs. However Tree Swallows, who also use the boxes for nesting, had a positive season, with an 81% success rate, occupying most of the boxes. There were also twelve House Wren nests, half of which were constructed on top of Bluebird or Tree Swallow nests. Male House Wrens are aggressive and will destroy the eggs and young of other birds in order to use the nesting area. House Sparrows will also evict any nesting bird to take over the site, although only three House Sparrow nests were found in the boxes. House Sparrows are less tolerated around Bluebird boxes than House Wrens because House Sparrows are invasive species. First released in Brooklyn in 1851 from Europe, House Sparrows have become one of the most abundant and widespread songbirds in North America. Other unwelcome wildlife includes paper wasps found in five boxes and a White-footed Mouse in one box. In conclusion, 72 out of the 76 Bluebird boxes were active; meaning that a bird at least attempted to build a nest there, and of these 72, 70 were actually used to raise chicks.     

House Wren nest with six chicks inside stacked on top of a Bluebird nest

Summary of Bluebird Nest Box Usage at White Memorial in 2011

Eastern Bluebird photo by Bob Stanowski

Eastern Bluebird Used Nest that Successfully

Fledged 3 Young from a Nest Box in

White Memorial's Mill Field

photo by Dave Rosgen

Tree Swallow photo by Darlene Knox

House Wren photo by Ann Cook

from www.learner.org

The 2011 nesting season was a record-breaking success for Eastern Bluebirds, but a near disaster for Tree Swallows using CT. Bluebird Restoration Project nest boxes on White Memorial Foundation land. Weather was a major player in these results. While Bluebirds either timed their nesting activity right or just got lucky, they managed to avoid the worst of the awful cold, wet weather that plagued Northwest Connecticut for parts of May and June. Many of White Memorial's Bluebirds made their first nesting attempt and successfully fledged young during a nice stretch of weather in May, then delayed making their second nesting attempt until nice weather returned in July. One pair even nested successfully 3 times this year!

Connecticut Bluebird Restoration Project

Summary of bluebird box usage at: The White Memorial Foundation

Towns: Litchfield & Morris

Year: 2011 Number of boxes: 82

SPECIES	# of Pairs	# of Active Nests	# (%) Successful	# Failed	# of Young Fledged	# Fledged per Active Nest
Eastern Bluebird	19	25	23 (92%)	2	91	3.6
Tree Swallow	50	51	39 (76%)	12	170	3.3
House Wren	5	6	6 (100%)	0	20	3.3
Black-cap Chickadee	2	1	1 (100%)	0	5	5.0
Tufted Titmouse	0	-	-	-	-	-
White-br Nuthatch	0	-	-	-	-	-
TOTALS	76	83	69 (83%)	14	286	3.4

Unwelcome Nest Box Tenants

SPECIES	# of Boxes Occupied	# of Nests Removed	# of Successful Nests	# of Young Fledged
House Sparrow	6	5	3	7
White-footed/ Deer Mice	3	3	-	-
Paper Wasp	6	12	-	-
Dominion Wasp	-	-	-	-
Ants	4	8	-	-
TOTALS	19	28	3	7

A record-high total of 19 pairs of Bluebirds used our nest boxes this year. Of their total of 25 active nests, 23 were successful in fledging a record-high total of 91 young. That made for an excellent success rate of 92% and productivity rate of 3.6 young fledged per active nest. They only suffered 2 nest failures: 1 due to a House Wren destroying a clutch of eggs and the other due to a huge Raccoon eating a clutch of eggs. More on him later. Tree Swallows started their nesting activity slowly in April and May and plugged along trying to nest and bring-off a brood of young through June's horrible weather. Many of them met with failure. Actually, some of our 50 pairs of Tree Swallows suffered from more causes of failures than just the weather this year. A huge Raccoon somehow found a way to climb up the otherwise Raccoon-proof PVC pipe predator guards on 4 nest box poles and get the eggs in the boxes. Non-native House Sparrows caused 2 of the Tree Swallow failures, and a House Wren caused 1 failure. Otherwise, 5 of their record-high 12 failures were caused by the foul weather. Despite this, they still managed to fledge 170 young from 39 successful nests. This gave them a nesting success rate of 76% and a productivity rate of 3.3 young fledged per active nest. House Wrens don't use many of Bluebird boxes because we try to keep them out in the fields, away from edge habitat that Wrens prefer. Still, 5 pairs of House Wrens did nest in them this year. They were 100% successful in their 6 nesting attempts, and fledged a total of 20 young. Two pairs of Black-capped Chickadees attempted to nest in our Bluebird boxes. One didn't get beyond the nest building stage before a Tree Swallow usurped the box. The other pair was successful in fledging 5 young. The overall figures were good, despite the Tree Swallow's contribution of failures. A total of 76 pairs of native birds made a total of 83 active nesting attempts in the nest boxes. Of these, 69 were successful and 14 were failures. They fledged a total of 286 young. That gave them a combined success rate of 83% and productivity rate of 3.4 young fledged per active nest. As for the unwelcome nest box tenants, House Sparrows tried to nest in 6 of the boxes. Despite removing a total of 5 nests, they still managed to fledge a total of 7 young from 3 late nests that slipped past us. Other problem critters included Mice in 3 boxes, Paper Wasps in 6 boxes, and Ants in 4 boxes.