Survival

Sparrows

In our neighborhood I found a bluebird box with sparrows in it. About a week ago there were three nestlings in it. Yesterday there was one barely alive and today nothing. The parents remove the nestlings that do not survive. Sparrows can feed on seeds but they feed their nestlings insects and caterpillars. Last week was a cool week. They had to survive themselves to try nesting again.

Sparrow's nests are often round shaped with a a roof over and just the opening on the side. I believe that was the same box. I checked them all in that section and none had nestlings. One box actually had five bluebird eggs but they mysteriously disappeared, all but one, over one day. Yes, there are other birds that eat eggs. These boxes are cleaned out once a year by someone. They are in no way ideal for bluebirds, being so close to a bike path. But some use may come of them. at least house sparrow nests.

Bluebirds

Our South side birds are doing well. It looked like whatever work on the trail (with bulldozers) had gone on was wrapping up.

 In what I call Box 13 are five nestlings. The mom never left the nest on previous visits but on a warm day like today the nestlings were alone, content from the morning feedings and sleeping. In fact the dad came by with food and nobody responded so he ate it himself. The dad is in some brush not far from the nest:

Here is the mom on the nest when she still had eggs.  

 

And the resting nestlings. The Box 13 family.  I think we are at day 4 or 5.

There will more pictures of the Box 7 family soon enough, There was a similar clutch inside. Here is just the box. I have never seen the female but she kept the eggs warm through the cold spell. I have a picture of the empty grass nest from it in the previous blog, look back.

The birds seem to like the compact boxes. Some bigger boxes are available and some brand new. One more box (2) had five eggs in the South end. So we are expecting up to 15 nestlings on the South side (now locked at the bridge)

Swallows

Swallows were fighting over Box 1 on the South side and Box 11 on the North side. Up to three males circle the box, land, go inside and so and. This is just to show to a female that "I have a nest box". I believe he does not make any nests. 

The surprise of the week was a swallow's nest with nestlings when all the other swallow nests do not even have eggs in them. Among the feathers (sign of swallow nest) were some sleeping nestlings. 

The swallows must have found enough insects to feed the nestlings and themsleves. In bad weather, bluebirds can find berries. I think these swallows may be able to eat some vegetable matter as well. Of all the swallows, these are the most song bird like and have feet to land and walk on unlike useless barn swallow feet. In the swallow category, I found a dead male in a box. The birds roost in empty boxes all year, This one was probably old or sick. I have to remove some dead things once in a while. If eggs start to rot they have to be taken out.

All in all, life goes on. People running bluebird nest box lines have always been impressed that they seem to plan well and rarely abandon eggs and never nestlings. It is all  a matter of survival and doing your job. People that study bluebirds say they live one or two years and very few nest and live to the third year. They make the most of it.