Wren House Adventures

Wren House Adventures

By Doug Donaldson 

A few years ago, my wife and I noticed a pair of beautiful little Bewick’s Wrens frequenting our backyard feeder. Eventually my wife discovered they had created a nest in the folds of an old tarp stored by our shed.  We kept an eye on the nest, but one night it was raided and destroyed. It was clearly time to build some wren houses!  

Bewick’s Wren by Doug Donaldson

 

Birdhouse Assembly by Doug Donaldson

I found some old redwood fence boards that could work for this project and checked the internet for some design ideas and other guidance. I found quite a few website resources and sensed a consensus that the proper sized entrance hole for Bewick’s Wrens was 1 1/8 inches wide, 4-6 inches above the floor of a 6-8-inch-high wren house.  It didn’t take long to cut the walls, roof boards, and bottom for two birdhouses on my table saw, but I discovered that I had a hole saw blade of 1 1/4” but not 1 1/8”. I used the blade I had to cut the entrance hole, assembled the birdhouses and hung them in some tree branches 6-7 feet above the ground (within the range recommended by my internet sources). 

Birdhouses by Doug Donaldson

A year went by. We continued to see Bewick’s Wrens frequent the feeder. But none showed interest in my birdhouses. As we got to know the wrens better, we observed that they preferred the cover in dense shrubs and bushes, typically flying into a thick bougainvillea against the house or a Hebe shrub near the feeder. 

Nesting Wren by Doug Donaldson

So, I decided I would put a birdhouse in a place they like. I built two more birdhouses just like the first two, but with one difference. This time, I went to the hardware store and purchased a 1 1/8-inch bit, making entrance holes of the recommended diameter.  I hung one house inside the bougainvillea and another in a thick camelia bush nearby. 

Nesting Wrens by Doug Donaldson

Bingo! We quickly noted that the wrens were very active in the bougainvillea and discovered a pair was building a nest in the new birdhouse. We didn’t notice immediately, but the other house (in the camelia) was soon occupied as well. We watched and I photographed the busy parents. Eventually, two newly fledged chicks came into the picture. Wren sightings around the feeder were very common, with many flitting in and out of the bougainvillea.  

Rarities and sunshine at 2019 SF CBC

Rarities and sunshine at 2019 SF CBC

By Siobhan Ruck

Thanks to all participants in this year’s San Francisco Christmas Bird Count – we had a great turnout and a clear (but chilly) day for counting.

Count Week is still going through Monday 12/27.  Hoping we can still pick up a few more species!

Counting at Crissy Lagoon. Photo by Ilana DeBare.

First the high points:

Black was the theme for uncommon warblers:  Black-throated Grey, Black and White, and Blackburnian were all seen.  Some uncommon species that seem to be becoming annuals were Tropical Kingbird, Blue-grey Gnatcatcher, Western Tanager and Orchard Oriole.

Tropical Kingbird at the Sharp Park Golf Course, by Joseph Morlan

Among the less-frequently reported species, we had a Redhead and Rhinoceros Auklet (Sloat seawatch), and Northern Fulmar (Funston afternoon seawatch).  The continuing Rock Sandpiper at Heron’s Head showed up on count day (a first on SF Count) but the Red-Footed Booby did not.  We do have the Booby for Count Week, but if anyone saw it yesterday, please get in touch.

Rock Sandpiper at Heron’s Head Park by Peter Seubert

Two other species were reported by people not on count teams:  Tree Swallow, and Palm Warbler at Concrete Bridge in Lake Merced.

In addition to the Rock Sandpiper, we had four other additions to the list:

  • San Bruno Mountain had a Pacific-slope Flycatcher.  Erica Rutherford found it while scouting on 12/26; they looked for it throughout count day – and it finally showed up at 4:08 pm, the exact time it had been seen the day before.
  • Crystal Springs had a Chateura-type swift, most likely Vaux’s Swift, flying with a flock of White-throated Swifts.
  • Sunset had a Scarlet Tanager at the Zoo, as reported to SF Birds last night. See Megan Jankowski’s post on the SF Birds email group for details.
  • Pacifica had a Long-eared Owl.  Because this is a species of special concern, the location has not/will not be shared, but the bird was well seen and photographed by the counters.
Common Goldeneye at Heron’s Head Park by Peter Seubert Counting in Colma, city of cemeteries, by Laurie Graham Tallying up the morning results over lunch at the Randall Museum. Photo by Ilana DeBare.

I’m still waiting for paperwork from a few areas, but the current numbers show 177 species seen on count day.  (179 pending documentation from the non-count observers)

A few common/annual species were missed – if you see any of these through Monday anywhere in the count circle, please let me know:

Wood Duck
Eurasian Wigeon
Cinnamon Teal
Northern Pintail
Long-tailed Duck
Green Heron
Ridgway’s Rail
Red Knot
Burrowing Owl
Hermit Warbler

This year’s count was notable for a number of terrific new area leaders.…

Birds and Berries

Birds and Berries

By Chris Carmichael

This is the time of year when images of birds feeding on red berries abound: Think of all those holiday cards featuring a chickadee on a snow-dusted holly bush.

As Bay Area residents, we don’t have snow-dusted bushes, but many of our local birds do rely on berries. For some, like Cedar Waxwings, berries form the basis of much of their diet year-round, supplemented with insects, particularly during the breeding season. The Phainopepla relies primarily on mistletoe berries to survive in the arid habitats where it occurs. Many birds that feed mainly on insects or seeds opportunistically supplement their diet with berries, often during the cold months of the year.

Bushtit with red berries, probably Chinese pistache, by Steve Zamek

Here in the Bay Area, several native berry-producing plants come to mind when we consider landscaping to support bird life. The toyon (Heteromeles arbutifolia), in the rose family, creates the classic winter holiday image when decked with birds feeding on its berries. At the U.C. Botanical Garden at Berkeley where I worked for many years, I’ve watched American Robins and Cedar Waxwings strip toyons bare in no time, savoring the red-orange fruit.  (Check out the video of waxwings feeding at the bottom of this post.) Northern Mockingbirds seem to favor toyon as well.

Cedar Waxwing with toyon berries by Steve Zamek Northern Mockingbird with toyon berries by Steve Zamek

Several other native berry-producing plants readily draw birds to their bounty of fruit, including blue elderberry (Sambucus nigra ssp. caerulea), various currants (Ribes spp), coffeeberry (Frangula spp.), poison oak (Toxicodendron diversilobum), Oregon grape (Berberis spp) , dogwoods (Cornus spp.), and brambles (Rubus spp), to name a few.

Fruiting Pacific crabapples (Malus fusca) naturally occur north of the Bay Area, but locally at the Botanical Garden, they’re magnets for Purple Finches, if the Robins leave them anything to eat! And during this year’s Christmas Bird Count, it was a pleasure watching a pair of Wrentits feeding on the native redberry (Rhamnus crocea) fruit in the Garden.

Birds are also drawn to non-native berry-producing species in our landscapes, with two rose family relatives—firethorn (Pyracantha spp.) and cotoneaster (Cotoneaster spp.)—being prime examples.

American Robin on a cotoneaster by Bob Lewis American Robin with a berry, by Steve Zamek

When our native birds feed on these and other non-natives, they can disperse the seeds leading to an invasive plant situation.…

Valle Vista: Birding Hotspot

Valle Vista: Birding Hotspot

By Maureen Lahiff

This area—accessible with an EBMUD recreation permit—is sometimes known as Upper San Leandro Reservoir, but the reservoir is just part of the experience. What makes Moraga’s Valle Vista Staging Area a birding hotspot is an amazing array of habitats: grassland, chaparral, riparian willows and alders, redwoods and pines, mixed-forest deciduous trees, and fruit trees left behind by former residents. Oh, and lots of poison oak, whose berries are enjoyed by over 50 species of birds.

Appreciating the land and water

Now managed by the East Bay Municipal Utility District (EBMUD) for watershed protection, the land bears traces of past and current uses. There are bedrock mortars—used by native Jalquin people for pounding acorns—along Moraga Creek, which flows into Upper San Leandro Reservoir. The land to the east was part of the rancho granted to Joaquin Moraga and Juan Bernal in 1835. The Moraga Horsemen’s Association today leases land from EBMUD for horse boarding and riding; they actively manage about 100 acres of pasture near the head of Upper San Leandro Reservoir.

Fruit trees from bygone ranching days at Valle Vista Staging Area. Photo: Maureen Lahiff. Ruins of an old structure along the trail to the reservoir. Photo: Maureen Lahiff.

Two major forces have shaped and continue to shape the landscape: trees and water. Their stories are intertwined; as reservoirs were created, trees were planted around them to stabilize the hillsides. I’ve done my best to put together a brief set of facts using Internet resources. I think I’ve got the major sweep of things, but more knowledgeable readers may have facts to add or correct.

The Gold Rush caused a brief period of bustling logging in the hills east of Oakland. As Sylvia Linsteadt writes in Lost Worlds of the San Francisco Bay Area, “by 1854, the biggest trees were gone, and by 1860, all the mills had closed down.” Two of the logging boom towns are now under Upper San Leandro Reservoir; one may have been called Valle Vista.  There was a second wave of active logging after the 1906 earthquake. The redwoods we enjoy in nearby Redwood Regional Park are third-growth trees.

Nuttall’s Woodpecker at Upper San Leandro Reservoir by Bob Lewis

Widespread planting of eucalyptus began in 1910, led by the Pacific Water Company. Monterey pines were widely planted around the reservoir in the 1930s by the Soil Conservation Corps. Even if they were not plagued by a fungus causing Pitch Canker, Monterey pines have a relatively short life span.…

Bird-Safe Buildings advance in Berkeley, Emeryville

Bird-Safe Buildings advance in Berkeley, Emeryville

By Ilana DeBare

The cities of Berkeley and Emeryville took major steps last month towards enacting Bird-Safe Building laws. Noreen Weeden, Director of Volunteers at Golden Gate Bird Alliance, has been instrumental in winning approval of such laws in San Francisco, Oakland, Richmond, and Alameda, as well as the pending Emeryville and Berkeley ordinances. Here we speak with Noreen about her Bird-Safe Building work that has put the Bay Area in the forefront of this important effort to save birds’ lives.

Q: What is the status of the Emeryville and Berkeley ordinances?

Noreen: In Emeryville, the planning commission will review an ordinance in February 2020 and then provide final language to the City Council, which has already agreed they want a Bird-Safe Buildings policy.

In Berkeley, the planning commission will review ordinance language that has already been drafted. The next step will be to make any requested changes, approve it, and implement it in 2020.

Northern Waterthrush, an unusual Bay Area visitor, killed in a window collision in Berkeley / Photo by Douglas Greenberg

Q: How long have you been working on getting Bay Area cities to add Bird-Safe Building policies to their planning codes?

Noreen: We started in 2009. The way I got interested is that I was walking to downtown San Francisco, and on Third Street noticed a dead hummingbird. I wondered, ‘How did it hit the window and die?’ Then I noticed some resources from the American Bird Conservancy, which had just started writing articles about window collisions.

In San Francisco, we were talking at that time with the planning commission about the impact of nighttime lights on birds and promoting “Lights Out” guidelines for migration season. The commissioners were happy to hear about positive steps they could take, and said, ‘Come back to us with more things we can do.’ So we started talking to them about Bird-Safe Buildings.

Q: How big a danger to birds are window collisions?

Noreen: The U.S. Fish & Wildlife Service estimates that window collisions kill 1 million birds per day. That’s the low estimate; there are estimates that are higher than that. [Estimates range as high as 988 million deaths per year.] Often collisions occur where the windows are reflecting vegetation or the sky.

Q: Why do birds fly into windows so much?

Noreen: They don’t recognize glass as a solid, just as we don’t. We don’t like to admit it, but almost all of us have walked into a sliding glass door once or twice.…