2021 has begun, and we are already starting to prepare for the coming Spring. There’s no telling yet what the weather will be like between now and April, but there are already a few nest boxes that will need to be replaced along the creek due to the fires last year along with the usual wear and tear. We’ll also need to restock our bands and other supplies. If conditions are right, we expect to have even more nestlings to band this year than last!
It will be exciting to see what this year brings for our nest boxes and birds at Putah Creek and beyond. I was birding recently in Davis and saw many bluebirds without bands near our nest boxes. They could be newcomers, or they might be locals that hatched from natural cavities. We also continue to get reports from Davis and Winters residents on banded birds that have been re-sighted, which are a great addition to our data on the birds’ movements and survival. It’s always nice to hear from these folks and exchange bird info.
We have recently learned that the LNU Lightning Complex fires have had an extreme impact on the landscape along the stretch of Putah Creek from Lake Berryessa’s Monticello Dam to near Lake Solano. This includes Interdam, one of our long-standing nestbox sites. Sadly, that site has been extensively burned.
But this image sent to us by John Hansen shows us a ray of light: At least one nestbox was still hanging! This box has housed successful tree swallow nests in recent years, with five fledglings in 2018 and four in 2019. Recently, after the fire, several bluebirds were seen in this area, showing another glimmer of hope for the local birds.
I have not yet explored Interdam after the fire, but I plan on looking for any other remaining nestboxes. The nestboxes themselves can fairly easily be replaced, but I hope the burn area can still support a variety of bird and wildlife species as the vegetation slowly recovers.
The nestbox season is well over, and I’ve been spending time organizing and looking at this year’s data. This year, about 974 birds fledged our nestboxes, which is 145 more than last year! 476 of this year’s birds were tree swallows, and 385 were western bluebirds. We also had 83 house wrens, 25 ash-throated flycatchers, and 5 white-breasted nuthatches that fledged from the boxes.
All but the nuthatches had greater fledging success this year than in 2019. Western bluebirds had the greatest overall increase in number of fledglings: last year there were 196, and this year we had 385! As usual, tree swallows dominated the western portion of Putah Creek while western bluebirds thrived most in the middle and eastern end. Ash-throated flycatchers and house wrens did best in the middle portion.
The Davis Nestbox Network along the Covell Greenbelt finished its second year with new boxes on poles on the north end and much overall success. 15 out of the 20 boxes had at least one egg in them, and the boxes produced 85 fledglings in total (tree swallows and bluebirds).
*Soon I’ll update with our Bird Haven highlights from further north. There were several ash-throated flycatcher nests up there this year!
Lastly, I hope everyone is staying safe this summer. My thoughts go out to those affected by the recent fires throughout California.
As summer progresses, the birds are really finishing up their nesting season. We banded our last nestlings for the season at the end of July. The very last box banded was in the Davis Nestbox Network in north Davis – a brood of western bluebirds, the second successful nesting attempt at that box this year!
I’d like to give a huge thank you from me to the rest of our small nestbox crew and helpers this season: Estefania Maravillas, Monica Burnett, Danielle Fradet, Michelle Mah, Alison Ke, Melanie Truan, Isabella Calcatera, Doris Wu, Andy Engilis Jr, and Irene Engilis. Together we managed to keep up with banding and data collection to get a good record of the nestbox activity this season despite this year’s challenges. Thanks for all of the hard work!
Below is a sped-up video by Danielle Fradet from up at Bird Haven, banding the last box of nestlings there (ash-throated flycatchers) in mid July. (Click the image below to view the video on the MWFB Instagram page!)
Almost all the songbird nestboxes were used this year. At Russell Ranch a few weeks ago, one tree swallow pair seemed to be using a duck nestbox too!
Earlier in July, Dr Kevin Keel spotted one of our banded adult tree swallows at Lake Solano. He sent along the lovely photo below. This bird was most likely banded one or two years ago in Winters.
Now we only have a few boxes to check to see if they fledged successfully this week and the next. We’ll be switching to mostly indoor work with the data again now that the breeding season is done. It will be nice to be out of the hot weather more, but I hope to still see young songbirds around nearby.
There are a lot of young birds out and about lately along Putah Creek and elsewhere. Most of the nestlings have fledged by now, but they often stick around their old nestbox areas for a while. You might see them at the various parks along the creek in Davis and Winters, and they may be wearing our color bands on their legs, like this fledgling seen by Mary K. Hanson.
The color bands allow us to find the bird’s information in our records, including where and when it was banded among other details. This fledgling, like most young western bluebirds, also has many little white spots on its back and breast, as well a wide yellow gape along the sides of its bill. These are all indicators that this bird is less than a year old. Another way to tell is if the bird receives food or begs from another, though this bird has started finding its own food.
We are still waiting for some eggs to hatch in our nestboxes. Bluebirds, tree swallows, and ash-throated flycatchers are still active along Putah Creek and in the Davis Nestbox Network at various stages of nesting. The weather has been pretty nice and the birds seem generally healthier overall than last year. We’re looking forward to seeing more fledglings soon!
New eggs are being laid in many of the nestboxes as our birds start their second nests or get a late start. Meanwhile there are always at least a few birds that are old enough to be banded each week. Ash-throated flycatchers are still in the middle of their main nesting season, which is usually shorter and later than it is for our more common nestbox species (tree swallows and western bluebirds). House wrens seem to be done raising nestlings this year on Putah Creek.
It’s consistently hot here in the middle of the day lately, so our crews usually work in the mornings to beat the heat. Though it won’t be as busy as May, the banding season continues!
Many new hatchlings are expected to appear along Putah Creek again soon. There are currently over 40 nests with eggs all the way from Interdam (near Lake Berryessa) to Mace Boulevard in Davis. Bluebirds, tree swallows, house wrens, and ash-throated flycatchers are all still taking care of new and old nests along the creek.
The Davis Nestbox Network boxes have been put to good use by western bluebirds and tree swallows. So far 75% of the nestboxes there have been occupied this year. Only a few boxes currently have eggs or chicks now after the main wave of nestlings in May.
Our Bird Haven nestboxes have been very productive again this year as well. House wrens and ash-throated flycatchers are still fairly busy up there producing eggs and chicks. 26 broods have been banded so far, and there are now about seven new clutches of eggs.
The weather will continue to be pretty nice this week, so hopefully the birds will stay healthy and comfortable.
It looks like we’re just about to head into the usual lull in the banding season. The busiest part of the season is mostly over, but there is usually another smaller spike in nest activity a few weeks after that. Western bluebirds often have second or even third broods of chicks after the first ones fledge, and ash-throated flycatchers are producing their eggs and nestlings now.
We’re in the middle of the busiest part of the nesting season. Lots of nestlings are hatching, growing, and fledging right now, meaning we have to keep track of boxes to band and boxes to leave alone. Once chicks are big enough, we give them metal and/or color bands, and then wait a couple of weeks for them to leave the nest undisturbed. Even though there’s a lot to keep track of, this is my favorite part – seeing lots of baby birds growing up.
I also want to show how egg color can vary in bluebirds. We usually see bright blue eggs, but now and then the eggs are white! Earlier this month I found a nest with bluebird eggs that were almost completely white. They’ve since hatched into healthy chicks that I banded recently in Winters.
Have a nice Memorial Day weekend everyone, and stay safe!
Our nestboxes have a lot of eggs now, and many more nests! The Putah Creek nestbox trails from Winters to Davis all have active nests – tree swallows, western bluebirds, house wrens, and white-breasted nuthatches. The nestboxes in North Davis and up at Bird Haven are also very active. Within the next couple of weeks, a lot of eggs are expected to hatch, and soon after that we’re likely to begin the busiest wave of nestling banding this year.
Nests in Winters near Dry Creek. Top left: western bluebird nest. Top right: tree swallow nest with a lovely variety of feathers. Bottom: tree swallow nest with two eggs!
We don’t have any ash-throated flycatcher eggs yet, but we’ve observed adults around the creek, and I saw a pair together at one of our Winters sites. I hope they’ll have another good season.