Monday, March 25, 2013

Nest Building On The Bluebird Trail

Nest Building

This past two weeks we have been seeing a lot of nest boxes being visited by the males and in some cases by both the male and female bluebirds as a pair.

Although the male bluebird may take the lead in exploring nest boxes and trying to draw the female to certain sites, it is the female who makes the final choice of where the nest is built. This choosing can be done in a day, or it may take weeks. Again, pairs that have bred in the area before are usually faster at selecting a site; inexperienced pairs are often slower.
A couple checking out #18
Thanks Nancy for this photo!

The female is also the one that does all of the actual nest building. Males may carry nesting material during courtship, and a little later they may carry bits of it again, possibly to stimulate the female, but this never amounts to much real building. While the female is building, the male may even enter the nest and remove a stray bit of material. Why he does this is not known.
A nest can be completed in just 2 days but on average it takes 4-5 days. In some cases, especially early in the season, nest building may start and stop over a 6-week period. Thus, when you see nest building, do not be surprised if the birds leave and then come back, if they start to build a little in several boxes, or if they take a particularly long time. All of these patterns and more are just part of the tremendous variation in individual bluebird habits.

Bluebird nests are constructed of grasses, pine needles, fine weed stalks, and occasionally fine rootlets. The female gathers bits of material, flies to the box, and arranges it inside. To form the hollow in the nest, she will sit inside it and press her breast up against the sides. This is called molding. In some cases the female bluebird may be assisted by juvenile bluebirds as she builds her nest. They may have been her young from a previous brood.

Bluebird nests are airy and light but well built, and have a small, neat cup shape in the center. The center may be lined with finer grasses or rarely just a few bits of hair or feathers. Second broods or second attempts can occur in the same nest box; a new nest is just built on top of the old one. Sometimes old material from the previous nest is removed by the birds, but they will not try to remove the whole nest.

Since we are monitoring the boxes, we will be removing all nesting material after the young have fledged or immediately after a failed nesting attempt. This keeps the nest box clean and allows the new nest to be the proper height from the entrance hole. 

As we think spring is just around the corner, some of our hardy fellow gardener's have been preparing their garden beds for spring planting by digging them up or turning the soil in the beds. The birds love this as they are the recipients of these fat, tasty grub worms that you see in this feeder on the garden fence. We want say which beds these healthy worms came out of, that will be our secret. Thanks to those who have been walking the bluebird trail and taking photo's and notes of all that is happening on the trail.

This is the week that we start our monitoring of the activity and nest building of the 20 nest boxes along the bluebird trail. We will start recording and reporting the details on The Cornell Lab of Ornithology website.

In our next blog we will give you the activity and up dated information of what is going on in each of the 20 nest boxes. Keep the photo's, notes, comments and support coming, as it helps me a lot with keeping up with all that is happening along the bluebird trail.

You Can Help! Become a friend of the Bluebird Trail at the Green Meadows Preserve Community Garden.

Make your checks payable to MGVOCC/Green Meadows Community Garden
                              (Master Gardener Volunteers of Cobb County)

Mail your sponsorship to:  Jim Bearden
                                           1648 Oakford Court
                                           Marietta, GA 30064

For questions: Call Jim at 404-202-8755

We are a non-profit 501-3C organization, so your donation is tax deductible.

Thank you for being a friend and a big part of the conservation solution!    

Wednesday, March 20, 2013

About Bluebird Territories

Bluebird Territories

During the breeding season, bluebirds defend territories on which they tend to remain and carry out all of their activities, including nesting, mating and feeding. Bluebird territories vary in size depending on the availability of food and nest holes or boxes and the amount of pressure from other bluebirds trying to nest in the same area.

A male eastern bluebird
Territorial Behavior

Individual males or mated pairs arrive on the breeding ground, usually near areas where they bred previously, and start to explore nest boxes and natural cavities. As they become more attached to the area, each male begins to do two things: sing frequently from exposed perches and fly from perch to perch around the limits of his territory. Both of these behaviors seem to help make his presence known to neighboring males.

Both male and female defend the territory, with the female confining most of her defense to the nest site and its immediate surroundings. During interactions, male bluebirds chase off other males off their territory but do not chase off females; and in turn, females chase other females but not males.

Courtship: The Start of Pairing

When bluebirds first arrive on their territory, it may be as either lone males or as pairs from the previous season. In many cases, males arrive a week or two before the females and start to defend territories in favorable habitats. Once the territory is established they may advertise their presence to passing females through song. This is given from high exposed perches, and the song is generally quite loud. Song may be given as often as 25 times per minute.
Good view from high perch
Once a female arrives on the territory, the males behavior changes markedly. At this time he sings only occasionally, usually from low perches, and often very softly so that it is not easily heard from over 25 yards away.

He will also start a variety of other behaviors and displays that seem to call attention to the various nest holes or boxes on his territory. These same behaviors will be seen right away in the male if the pair arrive together on the territory.

Generally, when you see both birds, male and female go into a nest box together several times, that means that the two are paired and that they are likely to use that box as a nest site.

Courtship and nest box selection can take several days. So if at first a little occurs on one day and then the birds fly off, do not worry. They may return again that day, the next day, or several days later.

  Once two bluebirds are paired you will again begin to see different behaviors. One is termed mate-feeding, in which the male gets food and feeds it to the female. Sometimes she may crouch and wing-wave as she receives the food. Mate-feeding continues from the start of pairing on into the nestling phase.

I was out on the bluebird trail today and saw alot of activity around a number of nest boxes. I would encourage you to go and walk the trail, take pictures and record what you see. Write a comment on the blog telling me what you see. If you have photo's you would like to share, send them to or as a text to 404-202-8755. With your permission, I would like to use some of the photo's and information in my weekly blog.

Next week we will start the record keeping of all the activity going on along the bluebird trail and any nest building activity. We have nest building already going on in nest box #1 and #2, today a couple was making a decision to move into #3. Before humans offered nest boxes, bluebirds did not have a lot of choice about the location of their nests; they had to use what was available.

Today, one of the main places that bluebirds nest is in nest boxes. These mimic the natural cavities and in some ways can be improvements upon them. They are usually better situated, have entrance holes that exclude certain other bird competitors, and they are generally drier and better ventilated.

Coming in the next weekly blog up date will be activity along the bluebird trail, now that it is spring. More about the nest building process. Send me some comments and photo's for our next bluebird trail blog!

                      Wishing all our readers a Happy First Day of Spring!

Thursday, March 7, 2013

Great Showing for both days of our Bluebird Trail Tour

Having a short talk and overview before our walk. 
Thanks to all those who came out for the Bluebird Trail walk. Thursday we had 22 people who were interested in learning more about the bluebird trail project and walked the trail with us.

Many thanks to all those who helped with the wonderful food and beautiful table setup, the awesome door prizes, the overview of the community garden and the period planting project as well as the Native American garden.

Thanks to Rita for this picture.

Saturday we had 19 very hardy and brave supporters and sponsors who came out in the cold and snow flurries for the Bluebird Trail walk.                                                                                                                                   

Returning Birds: As most of you have seen, we have bluebirds at the garden, in the bird bath and around the nest boxes. Bluebirds may return to breeding grounds as lone birds, as pairs, and as small flocks. Pairs will stay if they find a suitable nest site.

Young bluebirds in their first breeding year often nest near where they were raised. It is believed that they may return to the general area of their birth and then explore outward from there for their own nest site. 

They may even prefer to breed at a site similar to the one in which they were raised, even to the point of picking a similar-style nest box such as # 5. Much of the coming and going in the early stages may have to do with food. On warm days the birds may try to feed near their nest site. Even after doing some nest building early in the season, they may abandon the area for another spot. The name of the game is variability. We have nest building activity starting in #1 and #2 this past week.
Territory: Bluebird Territories and Territorial Behavior, coming next week in our next blog update. Along with any nest building activity on the trail.