Tuesday, June 19, 2012

Nesting Birds of the Yellow Island Area: Offshores, Transients, and Locals

Borrowing terminology from the orca populations, the nesting birds in the area fall into three groups: off-shores (nesting on nearby islands but visiting Yellow daily), transients (nest some years but not every year), and locals (nesting consistently on Yellow.)

Three species fall into the offshore group: black oystercatchers, bald eagles and osprey. Low Island, part of the USFWS San Juan Islands National Wildlife, is the closest island to Yellow and has had nesting oystercatchers every year that I've been on Yellow. Usually one pair nest but some years two and this year four pairs have been active in the area. They have fledged young as early as the first week of August and as late as the third week of September. They are successful approximately three years in five with eagle predation being the biggest problem.
Adult sharing a limpet with a juvenile

Adult and juvenile; note the difference in beaks and eye color.

Bald eagles nest on Cliff Island in what WDFW calls eagle territory 501. (Kathy named the eagles Levi and Jean.) Both of the pair use Yellow Island's Douglas firs as 'hunting platforms'  for everything from salmon to ducks and gulls to mink and seal afterbirth and dead seal pups during the summer pupping season.
Dead seal pup for chow.

Lingcod for breakfast

The osprey are farther away on Crane Island. I can see the nest with binoculars but sometimes need the scope to determine if they are in the nest. They only occasionally make it to the Yellow area to fish. We see them around Yellow more when the young have fledged.

Transients include belted kingfisher, northern rough -winged swallows, spotted towhees, fox sparrows, olive-sided flycatcher, and chestnut-backed chickadee. The high bank on the south side of the east spit has two nest holes. For many years kingfishers used one of the holes and the swallows the other. Around 2005 both disappeared, then several years later nested again but are now gone again.
Belted kingfisher bringing food to the nest.

Northern rough-winged swallows: adult feeding young.

Spotted towhees and fox sparrows nested until ten years ago. Now they both winter here and every spring I am hopeful they will stay. But towhees disappear first followed by the fox sparrows in early May.
Spotted towhee



Fox sparrow

Olive-sided flycatchers returned this year after a four year absence. They had nested consistently up to that point. Their "quick three beers" call is a familiar to all bird watchers.

Chestnut-backed chickadees are one of my favorite birds. They are cavity nesters. Many years ago we had a very windy winter and lost half a dozen snags, several that had been used as nest trees for both chickadees and house wrens. The chickadees have not nested since but the house wrens only missed one year.
Chestnut-backed chickadee (CBC)

CBC bedraggled after a bath

The locals are in order of decreasing number of nesting pairs: white-crowned sparrows, song sparrows, rufous hummingbirds, northwestern crows, American goldfinch, house finch, orange-crowned and yellow-rumped warblers, house wrens, American robins and Canada geese (also an offshore.)

White-crowned sparrows arrive in late March and immediately begin setting up territories. I have counted up to 30 adult birds and have guesstimated we may have 15 breeding pairs. Song sparrows are resident birds and there may be six to eight nesting pairs around the island.
White-crowned sparrow with an earwig for junior

Feeding time

Song sparrows also like earwigs

Song sparrow chick ready for chow!

Rufous hummingbirds also arrive in late March, about a month after the flowering currant first bloom. Yellow hosts four to five breeding pairs every year. The colorful meadow seen on the header of this blog is called Hummingbird Hill. On a sunny day during peak bloom, one might see up to a dozen hummers zipping about defending their favorite flowers.
Male rufous hummingbird above paintbrush

Male rufous hummingbird

Northwestern crows have decreased in breeding pairs over the years. When we arrived in 1999, the previous stewards told us we had 14 nesting pairs. I think that was accurate and  we were inundated with baby crows during breeding season. Now just two or three pairs nest each year and they have not been successful. Eagles and ravens are the reason why. Apparently baby crow is very tasty. In August Yellow becomes a post breeding roost site for crows from San Juan Island. I have counted up to 400 crows flying in at dusk.
Northwestern crow

Goldfinches and house finches have several pairs nesting each year and always fledge a few young. In the fall Yellow becomes a roost site for the house finches when there can be 50 to 100 roosting in the madronnes.
American goldfinches: adult feeding young

The warblers, orange and yellow-rumped, each have one to two pairs yearly and when not raising cowbirds, are usually successful fledging young.
Male orange-crowned warbler on snowberry

Feamle orange-crowned warbler in serviceberry

Orange-crowned warbler chicks on nest.

Female yellow-rumped warbler

House wrens show up in April and are one of our noisier nesters. Each year we get one or two pairs and I have seen half a dozen young flying around on successful years. Likewise, we get one or two robin pairs each year but they are not always successful. Robins, along with white-crowned sparrows are the first birds to start singing in the dawn chorus around 0420.

Finally, Canada geese nest on many of the islands in the San Juans. When I first came to Yellow in 1999, there were nesting pairs on nearby Low and Nob Islands as well as those attempting to nest on Yellow. These are a recent addition to the San Juans with the first nesters noted in 1986. Unfortunately geese are destroying the vegetation on many of the islands they nest island. Early on it was not unusual to see several families of geese in the area with up to a dozen goslings. However, in recent years I have not seen a single gosling. Eagles are again the main reason although I suspect river otters, ravens and gulls all partake in goose eggs and in some cases the young. There were three nest sites on Yellow this year with up to half a dozen eggs. All were unsuccessful. Similar numbers apply to Low Island. My take on it is that nature is again balancing things out. The geese were introduced when eagle numbers were still fairly low. Their populations rapidly expanded in the absence of predators. Now the San Juans may be at carrying capacity for eagles. The result is, at least in the Yellow Island area, that the geese are not being successful.
Canada goose pair


Monday, June 18, 2012

Spring's Solstice Swan Song

With the summer solstice just a couple days away, spring's wildflower season gives way to the flowers of summer. Of course some species overlap both season's unconcerned about the calendar.  The yellows of mid to late spring, broadleaf stonecrop (Sedum spathulifolium) and woolly sunflower (aka Oregon sunshine) (Eriophyllum lanatum) fade into another round of yellows: Puget Sound gumweed (Grindelia integrifolia) and lance-leaf stonecrop (Sedum lanceolatum). Amazingly several western buttercups (Ranunculus occidentalis), first blooming in March,  are still in flower although I have already collected some buttercup seed.
Broadleaf stonecrop (lower left) and woolley sunflower

Puget Sound gumweed











Lanceleaf stonecrop
Likewise, another March bloomer, harsh paintbrush (Castilleja hispida), still offers patches of bright red on the north side.  But the main colors joining the yellows are the pinkish purples of the two onions, Hooker's onion (Allium acuminatum) and nodding onion (A. cernuum)

Hooker's onion





Nodding onion

Nodding onion

plus the another shade of purple from harvest Brodiaea (Brodiaea coronaria) 
and fireweed's (Chamerion angustifolium) deep bright pink.

Harvest Brodiaea

Fireweed

Clustered (or California) broomrape (Orobanche californica) is very rare but also part of this color scheme.
Clustered broomrape

Even yarrow (Achillea millefolium) has a pink version but the white is far more common.
Yarrow (light pink form)
Yarrow (white form) and nodding onion

A few white flowers from spring can still be found if you look closely. Western starflower (Trientalis latifolia) and field chickweed (Cerastium arvense) add spots of white here and there. The white flowered serviceberry is forming berries and its white flowers are replaced by the native shrub oceanspray (Holodiscus discolor).
White-crowned sparrow atop oceanspray.
Even the beach areas offer bits of color. Sea rocket (Cakile edentula, native, and C. maritima, non-naitive) offer a pale purple hue to the high intertidal
Cakile maritima

Cakile edentula
while Japanese beach pea (Lathyrus japonicus) shows off its bicolored purple.
Japanese beach pea

Do these represent the end the end of the flowering season? Not quite. Two species that have yet to bloom are brittle prickly pear cactus (Opuntia fragilis) and seaside rein orchid (Piperia elegans).


My plan had been to walk around today photographing all these species but alas it has been raining the past couple days. All the above photos are file photos from previous years.

Friday, June 1, 2012

Rufous hummingbirds through the flowering season

As I was sitting out in the morning drizzle enjoying my morning cup of coffee, I noticed the first flowers blooming on snowberry, Symphoricarpos albus. That is what got me thinking about the various plants I've seen rufous hummingbirds nectaring on. I had always thought hummers liked long tubular flowers. Boy, was I wrong! I looked back through my photo files and my first recorded event was in 2004 at my home in Mount Vernon. This hummer was nectaring off Ceanothus.

Since being on Yellow I have photographed them on several plants but not all that I've seen them nectar on.  The first bit of luck was with harsh paintbrush, Castilleja hispida. 


Castilleja blooms from late March into June so gets a lot of use by hummers. During that  same time frame camas, Camassia leichtlinii, is in bloom from early April until mid May. It's another hummingbird favorite.


After the camas and paintbrush are done flowering for the year, a couple late season bloomers take over. Fireweed, Chamerion (fomerly Epilobium) angustifolium, is a favorite and blooms mainly above our east spit. Quite often it is the only flower in bloom and the hummer that has staked its territory there spends much of his time defending it (quite unsuccessfully) against the other four to five pairs of hummers on the island (along with their young.)
Fireweed has yet to bloom this year but when it does, this is one photo that needs improving on.

The snowberry that got me thinking about this is also visited by hummers when all else fails. This can last into July when the males have already left and this year's young are abundant.


I've always associated the arrival of rufous hummingbirds with the flowering of red flowering currant, Ribes sanguineum. In actuality on Yellow, Ribes flowers well before the hummers arrive, sometimes up to a month before. But when the males do arrive this is the species they favor. Another early bloomer is fawn lily, Erythronium oregonum. I've only seen it once but was with a friend who documented a rufous hummingbird nectaring on it. Late season a third plant that I have yet to photograph hummingbirds using but know they do is orange honeysuckle, Lonicera ciliosa. Finally a tubular flower that hummers use on Yellow. I watched one the other day in perfect light but alas the camera was half an island away.

So a couple goals: this year photograph hummers on honeysuckle and fireweed, next year on flowering currant and fawn lily.

PS Yes, I was having coffee in the rain and these are the first blooms of snowberry this year - sans hummingbirds.