Thursday, June 27, 2013

Como Park Bluebird Trail Update: June 21st

 Post contributed by Sharon, volunteer Bluebird Trail monitor: 

There are a total of 24 young bluebirds and eggs on the trail this week.  Fourteen young bluebirds in three boxes are ready to fledge, so I did not open their boxes in order to prevent premature fledging.  In one box that had five bluebird eggs last week, there are only four this week.  In the box where the three eggs disappeared last week, five more eggs were laid, but one of them was punctured and I found it rolled up onto the rim of the nest, and removed it.  It is possible a wren is damaging the eggs and that post may need to be moved to a better site.  In the box that had one egg last week, there are only two eggs this week, which is a little strange, considering bluebirds usually lay 3-5 eggs per nest and those eggs should all have been laid by now.
      Four tree swallows are ready to fledge this week so I didn’t open their box, but I did see a parent bird flying up to it with some food.  The other tree swallow box has at least four over-a-week-old young birds in it.
      Four chickadees fledged last week, so I cleaned out their box and removed the chickadee portal guard that reduced the hole size so larger predatory birds couldn’t enter and disturb the chickadees.  Eight chickadees hatched in another box.
            The wren nest is still a mystery, and I didn’t open it this week, in case those young birds are near fledging.  Generally house wrens lay between 6-8 eggs that take up to 16 days to hatch and between 15-19 days to fledge.