Monday, July 30, 2012

A Tale of Two Nests

Nests of Brandt's Cormorant and Double-crested Cormorant
Nesting cormorants--upper left Double-crested; lower right Brandt's.
Photographed at Newport, Oregon on July 21, 2012 by Greg Gillson

Take a close look at the cormorant's nests. Do you note that they are constructed differently?

According to The Audubon Encyclopedia of North American Birds, the Brandt's Cormorant (lower right in front) builds a nest of marine plants, mosses, and grasses in a circular nest. On the right hand side of the upper piling are two fuzzy brown Brandt's Cormorant chicks.

On the left side of the upper piling is a nest of Double-crested Cormorant. Notice that is is built of "sticks and weed stems, lined with leafy twigs and grass."

There is actually a third species, Pelagic Cormorant in this photo. See the dark form up on the bridge just above the upper right hand Brandt's Cormorant? That's where they build their nests. On natural substrates they build nests on "remote and precipitous cliffs" of seaweed, grass, and rubbish.

Thursday, July 26, 2012

Xantus, Scripps, and Guadalupe

Scripps's Murrelet. 2007 off Newport, Oregon by Greg Gillson.
The American Ornithologists' Union this month split Xantus's Murrelet into two species (see my Oregon Seabirds blog article: Guadalupe and Scripps's Murrelet).

The origins of these names are not all that familiar to birders. Who were Xantus and Scripps? And where is Guadalupe?

John Xantus (1825-1894) fled to the United States from Hungary in 1851, escaping the unsuccessful war of independence from Austria. Soon he joined the US army, stationed in Riley, Kansas. There he developed an interest in natural history (in that age this evidently meant shooting mammals and birds, and collecting eggs and plants for museums). In California he collected "massive amounts of materials," including many fishes, for Spencer F. Baird at the Smithsonian. He made an expedition to Baja California, Mexico, in 1859, using Cabo San Lucas at the very tip of the peninsula as his base for collecting. (See also this biography of John Xantus). Xantus's described to science the murrelet that came to be named for him. Xantus also collected the hummingbird named for him by George Newbold Lawrence. Fifty-two species of plants, molluscs, lizards, insects, birds, and fishes were named for him. Xantus described to science many birds including Hammond's Flycatcher, Spotted Owl, and Cassin's Vireo (The Audubon Encyclopedia of North American Birds. 1980. John K. Terres.). Xantus eventually returned to Budapest, Hungary as a naturalist.

The murrelet type that Xantus originally described breeds primarily on Guadalupe Island, or Isla Guadalupe, about 150 miles west of Baja California, Mexico, and about 250 miles SW of Ensenada. (See Biology and conservation of Xantus's Murrelet in Marine Ornithology. 2006. Carter et al.).

In 1939 Green and Arnold described two forms of Xantus's Murrelets, including one breeding on Anacapa Island, California. They named the type specimen for Robert P. Scripps, on whose yacht they traveled to visit Anacapa. The Scripps family made their fortune in the newspaper industry in the Midwest, and most retired to San Diego. In 1903 E.W. Scripps and his older half sister, noted philanthropist Ellen Browning Scripps, provided funds to help create the Scripps Institution of Oceanography in La Jolla, California.

Recent research has discovered that both the Guadalupe and Scripps's Murrelets breed on the San Benito Islands without significant interbreeding. They have different calls and different facial markings. And now they are considered separate species.

Saturday, July 21, 2012

Field-friendly bird sequence

Barn OwlBarn Owl, Hillsboro, Oregon, 22 October 2009 by Greg Gillson.


The 13 categories of North American birds listed in the Field-friendly bird sequence: Part II are:

Swimming Waterbirds
Flying Waterbirds
Wading Waterbirds
Chicken-like Birds
Miscellaneous Landbirds
Aerial Landbirds
Flycatcher-like Birds
Thrush-like Songbirds
Chickadee and Wren-like Songbirds
Warbler-like Songbirds
Sparrow and Finch-like Songbirds
Blackbird-like Songbirds

A beginner should be able to quickly place a bird they see into one of these categories.

Raptors are birds of prey that hunt other birds and animals. They have strong beaks and claws. Many can be seen soaring high overhead, while others hunt low from a concealed perch.

Raptors include vultures, hawks and eagles, falcons, and owls.

Bald EagleBald Eagle, Tualatin River NWR, Sherwood, Oregon, 6 July 2010 by Greg Gillson.


Peregrine FalconPeregrine Falcon, Hillsboro, Oregon, 29 April 2010 by Greg Gillson.


Turkey VultureTurkey Vulture, Newport, Oregon, 12 September 2008 by Greg Gillson.


Red-tailed HawkRed-tailed Hawk, Hillsboro, Oregon, 6 December 2008 by Greg Gillson.

Wednesday, July 18, 2012

Where should I go birding in August?

 Hot and dry. That is August in the Pacific Northwest. Thus, birding in late summer is often concentrated around finding water where birds concentrate.

Even more than July, birding in August revolves around shorebirds at quickly-drying inland marshes and high tide roosts along the coast.

Another cool location is the high mountains. Access to alpine areas in August may provide you with views of many birds moving upslope to cooler wetter areas. It has been several years now, but I love camping in the park-like pondersoa forests on the east slope of the Cascades and making day trips to various surrounding areas to find wonderful birds amid snow-capped mountains and blue skies. Use the Oregon Cascades Birding Trail brochure as your guide.

If you want to get away from the heat, a pelagic trip at this time of year is often cool and frequently misty--at least in the mornings. Trips offshore at this time of year feature Long-tailed Jaegers, Sabine's Gulls, Arctic Terns, and Fork-tailed Storm-Petrels, along with the regulars like Black-footed Albatross, Pink-footed Shearwater, and Rhinoceros Auklets.

I'll be attending the 26th annual Oregon Shorebird Festival, August 24-26. The Bird Guide, Inc. will be hosting the pelagic trip for the Shorebird Festival, something we've been doing for several years now (sorry; no more spaces available!). The Friday and Saturday night presentations are top notch. Friday's speaker is Noah Strycker, speaking about his Antarctic adventures: "Among Penguins." Noah has subsequently completed walking the Pacific Crest Trail from Mexico to Canada. He's been busy! The field trips are led by knowledgeable and friendly local birders. Dawn Grafe, with the US Fish & Wildlife Service, has ably and cheerfully organized this Festival for several years. Attendance is only 60-100 persons. You shouldn't miss it!

Where are you planning on watching birds in the coming month and what species do you hope to see there? Are you a field trip organizer? We want to hear what you offer (fee or free). Leave your response in the Comments section as ideas for others.

Birding festivals:

Southwest Wings Birding and Nature Festival
August 1-4, 2012
Sierra Vista, Arizona

Oregon Shorebird Festival
August 24-26, 2012
Charleston, Oregon

Thursday, July 12, 2012

Wrentits in northern Willamette Valley

This spring and summer there have been several scattered reports of Wrentits in NW Oregon outside their historic range. Could the sightings and heard-only reports be correct? Possibly. On the other hand some might just be weather balloons.

Reports have come from North Portland, Sauvie Island Wildlife Management Area, Hagg Lake, and Tualatin River National Wildlife Refuge. Thus far, all these reports from well-birded areas are unverified--descriptions are incomplete and others can't find them the same or next day. That's a problem for me. I'll tell you why.

Wrentits are sedentary to the extreme. Their home ranges are a tiny 2-1/2 acres--a few hundred feet across. Pairs of birds mate for life and are never far apart (Terres, 1980. The Audubon Encyclopedia of North American Birds). Both sexes sing throughout the year--a very loud and unique bouncing ball whistled trill. On the rare occasions when birds have been found pioneering new areas they are rather easily and repeatably detected.

The range of Wrentit in Oregon hasn't changed all that much in 200 years. Historically, they were found along the immediate coastline in salal bushes under the scrubby shore (lodgepole) pine, from California to the Columbia River. They have never crossed the Columbia into the state of Washington, even though regular on the Oregon side of the mouth of the river. In winter they sometimes can be found a few miles inland into clearcuts. They also occur in the SW area of the state near Medford in low-elevation chaparral of the Rogue Valley, and in low numbers into the Klamath Basin.

Recently (the past 50 years or so), their inland population has inched northward through the Umpqua Valley to the eastern edges of the southern Willamette Valley in Lane County. A population has also crawled northward on the western edge of the Willamette Valley, from Finely NWR near Corvallis in the 1970's to Grand Ronde of Yamhill County.

There are three known isolated outposts north and east of this range. Birds were detected in the late 1990's near Lebanon. Birds this century colonized the Sandy River delta near Gresham. Birds recently arrived at Minto Browns Island Park in Salem. Especially is this last location hard to fathom. Birds either hopped across miles of city streets or somehow crossed the Willamette River. This from a species that refuses to come out of cover and is loathe to cross a single lane dirt road!

Of course, birds had to get to these new outposts by crossing miles of unsuitable and even dangerous (for a Wrentit) habitat. Thus it is possible that some of this year's out-of-range reports may be correct. I take comfort in my present skepticism, knowing that if birds really are present at these new locations they won't stay undetected for long.

Wednesday, July 11, 2012

eBird best practices
Add comments for rare birds

One of the great things about eBird is the data quality standard and review of unusual bird reports.

When submitting a checklist to eBird you are asked to verify unusual sightings. Perhaps there was a typo and you accidentally entered a high number or wrong species. However, don't just mark the checkbox verifying the entry is correct as you intended--give a reason.

You see, every time the automatic filters indicate you saw an unusually high number or unusual species, a real person reviews your list. Rather than waiting for the Reviewer to send you an email asking for more details, provide the details in the comments for any species that eBird flags as unusual. If you don't provide comments in your checklist and then don't respond to the eBird Reviewer's email request for more information, Reviewers have no choice but to invalidate your record.

Now it may be that the number you saw was just barely over the threshold, or the species is generally rare but your bird is a known rarity. In this case the Reviewer will simply verify your sighting from within eBird and your record gets accepted to the pubic database.

Whenever possible, the Reviewer is a local expert on the birds of the area. If they deem that your sighting is unusual enough, they will want more details. Plumage, behavior, habitat, songs and calls all help verify a locally rare species. Provide as much information as you can. Of course, digital photos are ubiquitous these days. Even a blurry photo from your camera-phone can help establish the identity of a species.

On the other hand, perhaps the species is expected, but in much lower numbers than you reported. Explain any reason for unusually high numbers.

Now the filter settings aren't perfect. The Reviewer is able to change the settings to more accurately reflect reality. If you think a species or high number is being flagged too sensitively, add a note to that effect to your comments as the Reviewer will read it. On the other hand, if you entered a bird you thought rare, but the filter accepted it without challenge, then you might also drop an email line to your Reviewer.

Reviewers are assigned by counties, though most reviewers are responsible for more than one county. They can help you with ID questions, status and distribution. They are a good resource for you to learn the local birds. They may suggest that you saw a more common bird. But remember, no one can change your records but you.

So, what happens if the Reviewer doesn't overturn the automatic filters and accept your report?

Firstly, the acceptance or not of a reported bird is not a reflection of you as a person or as a skilled birder. It doesn't mean you didn't actually see the bird you reported. It does mean that the bird was unexpected and you provided insufficient documentation to sway the decision. I have invalidated my own records when entering lists of birds from years long past because of lack of written details in my notes about an unlikely species.

Secondly, your list of species is always available to you, whether correctly identified or not, whether the Reviewer validated it or not. Remember, all records stay in the system and can be reviewed again. Invalidated records can be accepted and accepted birds can be reviewed and invalidated later.

What will happen though, is that your invalidated record will not appear on the public eBird maps and bar charts for abundance and frequency. Your records are available, though, to researchers, along with the Reviewer's comments, so they can make their own decisions.

I hope this provides some insight into the data quality of eBird and how providing comments on your checklist can save time and effort and help a Reviewer come to a good decision about flagged records.

More information:

Saturday, July 7, 2012

Nesting Western Bluebirds

There is just something special about Western Bluebirds. Whether I see them in rural farmlands or mountain clearcuts, they are always a joy to see. They are small and unassuming.They have a soft, cat-like "mew" or "bew" call. Even though the males are blue with rusty breasts, the colors aren't gaudy.The female's colors are even more muted. Everything about this bird is understated.

Several local birders noted the presence of these birds this spring in a clearcut along a logging road in the Coast Range above Hagg Lake, west of Portland, Oregon. While I was primarily looking for forest species like Hermit Warblers, Gray Jays, and Sooty Grouse, I spent some time watching the bluebirds and finally noted where they flew up to a snag at the edge of the forest. There they had a nest in an old woodpecker hole. These photos were taken May 29, 2012.

A couple of years ago I wrote a post on Western Bluebirds in the Willamette Valley and how they've made a remarkable recovery since the low point in their population about 40 years ago.