Field Notes

As 2015 comes to a close, it seems appropriate to tie up some loose ends before proceeding into the New Year.
And now would be a good time to wrap up last summer’s birdhouse summary for area cavity nesters. Twenty nest boxes have been installed, mostly on the grounds of the NRAO, and observed during the summers for each of the last eight or nine years. Every five to seven days the bird boxes get opened and information is gathered. Nest status, bird species using the house, number of eggs or number and status of young are written down and later submitted to the Nest Watch Network, a huge data collecting group based out of Cornell University. Hundreds of other bird watchers and interested parties, groups and clubs submit their results to the same database, giving Nest Watch one of the largest resources in the world for studying birding health and population trends and changes.
Each of the birdhouses had an opening of 1.5 inches which limits them to Tree Swallows, Bluebirds and House Wrens but the numbers can be interesting. The Bluebirds had 13 successful (one or more young fledged) nestings out of 17 attempts. From a total of 76 eggs, 50 young fledged out into a big, wide world.
These numbers beat the 2014 numbers by 39 percent as only 36 young fledged then from 10 successful nest boxes.
The tree swallows were not quite as lucky this year and were down considerably. Only six nestings out of 13 starts were successful and produced a total of 20 young. When compared to 2014 numbers of 11 good families and 49 young produced, we can see swallows were off by more than half.
House wrens were fairly successful with four good nests (out of six) and 23 young fledged.
Altogether there were 36 nesting attempts with young birds fledging 23 times from nest boxes. A success rate of 64 percent (and 93 young fledged) should be considered good. Not great, but good. In the wild, the expected success rate would be about 25 percent.
Birdhouses for cavity nesters increase their odds of success, so there is much demand for the best locations and boxes and most had at least two attempts in them during the course of the summer.
Unsuccessful nestings can be blamed on a number of predators such as other birds, mice, chipmunks, squirrels and raccoons. Some years, diseases and fly larvae can also negatively impact young birds and severely limit their numbers.
For the first time ever, I did lose three boxes to vandals and one to a bear who insisted on knocking the box off the metal fence post and chewing it up. A couple of wren families were lost then.
While I don’t attempt to monitor any Wood Duck boxes, I do watch and count the families and little ones that show up at our wastewater ponds every summer. Those numbers also appeared to be down somewhat as only six to eight young woodies (from four or more families) fledged compared to about 30 in 2014. Predation here is always horrendous from crows, hawks, foxes, turtles and snakes.
That wraps up our birdhouse numbers for 2015.
If you have bird boxes in your yard, don’t forget to clean out the old nests and repair the boxes that need work. Scrape down the insides with a flat scraper and sterilize with a 10 percent Clorox solution.
Birds can be a pleasant addition to any yard, but they may need your encouragement. Adding a few attractive birdhouses can increase your enjoyment of your yard and surroundings while adding to the overall health and well-being of our feathered friends.
And this….
Our record warm winter may be coming to an end as we all knew it would, but it has been very pleasant to this point. Several motorcycles and even a convertible or two were seen touring this past weekend. At work a tiny frog was found lodged in the rain gauge canister while temps neared 70 degrees F last Sunday.
In other odds ‘n’ ends, bear and deer season will both be concluded on the last day of December. Anyone with an interest in the proposed Elk Management Plan for the southwestern part of the state, the Department of Natural Resources is taking comments until January 15. The Plan is available at
Dave is a telescope operator at the Green Bank Observatory and can be reached at davecurry51@

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