Covell Greenbelt Bluebirds

Today, we checked the Davis Nestbox Network boxes along the Covell Greenbelt and found eggs in two bluebird nests! Each nest had five eggs belonging to unbanded adults. We also found one more egg in the tree swallow nest, making 6 eggs total!

An unbanded male bluebird checking in on his eggs

To our surprise, when we took down one of the nest boxes, there was a female inside the box incubating eggs! We put the box back up immediately and waited for her to fly out.

beautiful turquoise bluebird eggs

There was also a tree swallow inside the nest box when we arrived. Warm eggs means that the birds have been incubating.

tree swallow parent checking out the surroundings

Fingers crossed for nestlings next time!

-Alison Ke


First Nestlings

This week has brought us our first chicks! There are baby western bluebirds at our easternmost Davis site, and white-breasted nuthatches at the orchard site in Winters.


Western Bluebird chicks and eggs


White-breasted Nuthatch chick. Photo: Estefania Maravillas

We also have another first: The Davis Nestbox Network has its first eggs ever! The tree swallow parents were quick to take to their box. A few other boxes there have bluebird nests coming along.

We have gotten a good number of reports lately of re-sighted banded birds. It’s exciting to get this information and find out where and when the bird was banded, and to give this information to the birders who reported them. Sometimes we can narrow it down to one individual bird and find out what we had named them! If you spot any birds with colorful leg jewelry along Putah Creek, we would love to know about it and tell you what we can find out about them. In addition, you can report them to the USGS at


Western Bluebird with color bands, which tell us that he was banded as a nestling at the UC Davis Arboretum in 2017. Photo: DeLayni Millar.

Western bluebirds have been making use of our nestboxes successfully for about 20 years now. Here is an interesting article on bluebirds that explains the importance of monitored nestbox trails (focusing on eastern bluebirds, but it applies to our western species too):



We now have at least one nest and egg from each of our most common early-spring birds! (The ash-throated flycatchers will start arriving later in the season.) Here’s a bluebird nest that already has five eggs:


Tree swallows are dominating many sites so far, and others have an abundance of house wren nests in the works.


House wren nest, not yet completed

Our many helpful volunteers have been checking nestboxes with us starting earlier this month. The rain seems to be mostly over with for now, so more of our flooded nestbox areas are becoming accessible. We’re expecting many more eggs to come.


First family moves into North Davis nest box neighborhood

Three weeks ago, we saw two feathers: the first signs of tree swallows investigating the real estate by North Davis Ponds.

Tree swallows construct their nests using mostly grass and feathers of other bird species.

This week, a group of 6 of us returned to the box and found that the adults have chosen this box as their home! They have put in a lot of work to fix up the interior. Today on the Friends of North Davis Ponds First Saturday Bird Stroll, I saw both tree swallow adults going in and out of the box, working hard to prepare their home for eggs.

The nest three weeks later. It looks almost ready for eggs!

I am very happy that one of the Covell greenbelt nest boxes is occupied during this first season that we put them up. Hopefully, more birds (and bluebirds in particular) will begin to use them next year, if not later this season. Indeed, I have observed a few bluebirds every time I have walked around the greenbelt. I am also happy with the great turnout, pleasant weather, and successful monitoring this first week of the Spring quarter!

-Alison Ke

All interns got to experience taking down and putting up nest boxes for the first time.