A 'Moon' Bird

Each week we eagerly start the bluebird monitoring at 8:30 in the morning, usually a Tuesday, to find the latest happenings in the boxes along the trail. It is a delight to be at the garden enjoying the beauty of the surroundings as well as seeing the bluebirds and hearing their lilting calls. Folks driving by and on their way to work give us a friendly wave when they see us peeking in boxes. We're part of the scenery and that's confirmation that all is well.

That is, we hope all is well but we are having a few surprises from time to time. Sometimes a box that had five eggs in it the week before might have only one egg remaining. Or the chicks that were newborn have disappeared. Or the nest has been completely abandoned. We conclude that predators are the culprits. It's sad but it's also the way of nature and every animal has to have a meal now and then. A couple of boxes that are near the ponds have been vandalized. Snakes are suspect but one box has claw marks on it which suggests a raccoon. We make notes of all these happenings in our notebook.

The biggest surprise has been a tree swallow that refuses to leave the box when we try to check on it. That mother bird is steadfast. She does not budge. We even used a flashlight in an effort to confirm her identity and all she did was show us her backside. Imagine that! Being 'mooned' by a bird! Tree swallows are known to use bluebird boxes and, in fact, sometimes are regarded as pests. However, this is the first year that one of our boxes has been used. Maybe in the next week or two, we'll be able to peek at what's going on inside that box. Mama has to leave sometime in order to gather insects for the chicks. If we're lucky, she'll be gone when we come along.

As to the "blues" themselves, everything is on course for this time of the season. Chicks have fledged and second nestings have begun. Life continues and it gives us many surprises along the way. That's the way it should be.

Fresh Faces and the Evil Eye

With the end of April here, there are twenty-three bluebird chicks being fed and nourished by doting parents. Within the next week, ten of them probably will be out in the world learning the ways of chasing their own food. In addition there are forty-four eggs being incubated so the bluebird season is well on its way.

We have nests in seventeen of the thirty-three boxes. This is a slight increase over the number of nests last year at this time. Also, there are chickadee and titmouse nests in three of the boxes but we don’t include those in our data.

Unfortunately there is evidence of predators in the bluebird nests as some of the eggs have disappeared. The nests themselves don’t seem to be disturbed and we don’t find the eggs on the ground near the boxes so perhaps snakes are invading and eating them. Also, we are seeing the stick nests of house wrens in one box. The wren is persistent and we do remove them because, at this point, they are only the beginnings of nests and no eggs have been laid. If there are eggs or chicks in those nests, it is not lawful to remove them.

House sparrows have chosen one particular box for their use. They are a threat to the bluebird population so their nests are being removed also. House sparrows are not native birds and, therefore, not protected by law. They are messy birds and use lots of trash in their constructions. We’ve found materials such as cellophane, cigarette butts, and goose feathers. Like the house wrens, they will destroy bluebird eggs as well as chicks and sometimes prevent bluebird parents from entering the box.

As we peek into the nests, we are finding that the mother bird sometimes refuses to leave the box. We knock on the side of the box to make the bird fly out and when we open the panel to peek in, the bird is in there and just gives us the evil eye. When mama is glowering at us and refusing to budge, then we just tell her we’ll wait until next week to see what she’s hiding. Maybe her mood will be better then.

That’s the status of things along the bluebird trail here at the garden the last week of April.

So Who Is Really Living Here?

It’s not that we don’t like House Wrens. We do appreciate the male’s beautiful warbling song that lets us know there’s pride in his chosen nest site. It’s just that he has chosen a nestbox that is supposed to be for the Eastern Bluebird. The bluebird builds a tidy nest, usually with pine needles because of their availability but we’ve seen dried grass used also. However, the House Wren stuffs the box with coarse sticks, cramming them in so tightly that it’s almost impossible to check for eggs. The actual nest cup is deep inside along the back side of the box so we dutifully (and carefully) tilt the nest outward and downward in order to see into it. If there are eggs or chicks, we leave them. However, if it’s the beginning of a nest we remove it but, usually, the next week the wren has been at it again.

Now we have discovered something new – new to us, that is. There are double layer nests in some of the boxes. The House Wren is either an opportunist or is lazy but, then, there may be a fine line of distinction there and could be a subject for musing in a different venue. On the bluebird trail here at the garden, we have several nestboxes in which the bluebirds started building nests but, somehow, the wrens took over. After all, they are feisty little birds. In one there was one bluebird egg already laid and we expected to find a few more eggs the following week. Instead, we found a stick nest built on top of the pine needle nest and the bluebird egg was gone.

We know that House Wrens usually choose boxes that are near woody areas and we thought we had placed them far enough from trees and bushy areas. However, now we know these birds will use boxes that are out in open areas and, in fact, will take over the boxes already being used by the bluebirds.

Wrens are known to destroy bluebird eggs by punching holes in them, but they also will attack chicks in the nest and toss them out. They are a major problem if one is trying to have a successful bluebird trail. Obviously we are distressed when we find these stick nests, but we also know that it’s nature at work. But double layers? Oh, come on!

What's New on the DSBG Bluebird Trail

May has been a busy month for the bluebirds at the Daniel Stowe Botanical Garden.  The first brood of chicks from the nest boxes have fledged their nests and we are now seeing the second brood of the year.  We noted that 8 of the nest boxes have a second brood and we counted a total of 28 eggs in those boxes.  We also have one box with an active house wren nest.

If you are monitoring a bluebird box in your own back yard, do not be alarmed to see that the number of eggs in the second brood is smaller than the first.  This is what we are seeing as well. We do have some smaller broods of just one, two or three eggs.

This year on the bluebird trail we had a slightly rare occurence in one of the nest boxes that we did not observe last year.  During our monitoring of the boxes on April 30th we discovered that one nest box contained white eggs!  The photograph above was taken on that day.  After checking the box we drove a short distance away and waited.  Sure enough a female bluebird flew right into the box. The eggs were also consistent with the size of the blue bluebird eggs that we are noting in the other boxes and the nest was consistent with the other bluebird nests.

According to www.sialis.org, up to 4 to 5 percent of bluebirds lay white eggs.  The Sialis website also indicates that white eggs can occur in all three species of bluebirds and that the white eggs are just as fertile as the blue eggs.  From what I read on this website, a female that lays white eggs will always lay white eggs.  So, if we have blue eggs in the same nest box for the second brood, then another female has now inhabited the box.  It will be interesting in the coming weeks to see if we have white or blue eggs in that same box.

As always, one other good thing about being outside monitoring the bluebird boxes is that it affords us the opportunity to see what new visitors we have flying around the garden.  In addition to the usual suspects we saw a few new species of birds during May that we did not see in April.  We observed the Indigo Bunting, American Goldfinch, Barn Swallow, Red-winged Blackbird, Orchard Oriole, Red-eyed Vireo and the Chimney Swift.

When you pay your next visit to the garden I hope you'll take some time and observe the birds as well as the beautiful plants and flowers.  Please drop us a line if you see a species of bird that you do not normally see so that we can be on the lookout for them as well.  Enjoy the garden and happy birding!

What We Don't Want To See On The Bluebird Trail

There have been a lot of things going on during the past few weeks on the Daniel Stowe Botanical Garden Bluebird Trail.  Just in the past week alone we discovered that 19 bluebirds fledged their nests.  We have at least 6 active nests and we have 4 nest boxes that are active with wasps.  We are definitely having more problems with wasps this year than we did last year.

The picture at the right is a picture of what we don't like to see on our bluebird trail.  This is a House Wren nest.  The Migratory Bird Treaty Act of 1918 protects these little native birds that build these big, clunky nests.  The Act makes it illegal to remove active nests or eggs of the House Wren.  It is acceptable to remove House Wren nests without a nest cup or eggs.  You can see from this picture that it would be very difficult to determine whether or not there is a nest cup or eggs in this box.  So, to be on the safe (and legal) side, it is best to let nature take its course at this stage.  This is what makes regular monitoring so important.  Early detection makes it possible to remove the sticks before a nest cup is established and eggs are laid.

We also discovered one nest box being inhabited by a Tufted Titmouse.  This bird is also protected by the same act so she'll be raising her brood without any interference from us.  The Tufted Titmouse makes downy nests of moss, fur, soft plant fibers and occasionally crumpled leaves.  It is easily distinguishable from the pine needle nests that bluebirds build.  It looks extremely soft and comfortable.  If I were a baby bird I think I'd like this nest quite a lot!

We also had one more visitor to a nest box this week that is also protected by the Migratory Bird Treaty Act.  I noticed two tree swallows flying around one of the nest boxes.  One of the birds landed on the front of the box and held on and sang away at the entry hole.  So, next week the monitoring could be very interesting.  We may just get the opportunity to see what the Tree Swallow's nest looks like as well.

So, do pay a visit to the garden soon.  Sit a spell and see what else is flying around in the air besides wasps, bees and pollen.