Vireo frustrations

I hate not being able to put a name on a bird. Sometimes the course of wisdom, though, is to say, "I don't know." Some birds are glimpsed only briefly, or at a distance. Some birds are notoriously hard to identify and require excellent looks. And hybrids can be a problem for some groups of birds. But when you have excellent photographs of the bird and are still unsure? That's frustrating!

So it was that on October 23rd I found a Solitary-type vireo in Escondido. A few years back the Solitary Vireo was spit into 3 species: Cassin's in the West, Blue-headed in the East, and Plumbeous in the Inter-Mountain West. I have seen all three, but only Cassin's regularly, and more often heard than seen (or heard first then observed as barely more than a silhouette moving through the forest canopy).

When the bird first appeared I was convinced I was viewing a Plumbeous Vireo. There was great contrast between the dark gray head and white eye ring and supra-loral ("spectacles"). The wingbars were wide and white. I could detect no green or yellow tones in the field. Many Cassin's Vireos are quite greenish overall, but this bird was very gray and white.

However, when I got home and transferred the photos to my computer, I could definitely see a pale yellow wash to the sides. The back that looked so gray in the field now had a slightly olive cast to it. Did that mean it was actually Cassin's?

Eventually I put it down in eBird as "Cassin's/Plumbeous Vireo"--a safe, but ultimately unsatisfying, "non-identification."

Time for some research.

Mystery Vireo. Kit Carson Park, Escondido, California. October 23, 2016. Greg Gillson.

Mystery Vireo. Kit Carson Park, Escondido, California. October 23, 2016. Greg Gillson.

Mystery Vireo. Kit Carson Park, Escondido, California. October 23, 2016. Greg Gillson.

Both Plumbeous and Cassin's are rare fall migrants to San Diego. Both are partial to conifer and mixed woods. So habitat and seasonality don't favor the chances of one over the other. If it was later in winter, Plumbeous is more regular as a rare wintering bird than Cassin's.

My research found that this vireo undergoes a complete molt in fall. Indeed, the bird shows fresh, crisp, new plumage. This is the brightest and most colorful plumage of the year. From here on out over the next 10-11 months the plumage will wear and fade. So my initial feeling that the bird was Plumbeous was perhaps more due to the unfamiliar-to-me fresh fall plumage--I usually only see Cassin's in duller spring and summer plumage. ["Plumbeous Vireo: the range of misconception," BirdFellow blog, Dave Irons, 2014.]

In very worn plumage the Cassin's Vireo can approach Plumbeous in colorless gray with little hint of yellow on sides and secondary edging. After the fall molt Cassin's can appear nearly as bright and colorful as Blue-headed Vireo. ["Spectacled Vireos," PRBO Observer, Rich Stallcup, 2007.]

[Unfortunately I do not have access to Heindel, M.T. 1996. Field identification of the Solitary Vireo complex. Birding 28:458-471.]

Since this bird is in fresh plumage and is still rather gray with a hint of yellow on the sides, a slight olive cast to the back in one of the photos, and at most only two outer secondary feathers a bit yellowish, it would seem to best match Plumbeous Vireo... maybe.

Plumbeous is supposed to have a larger bill and longer tail than Cassin's. I don't have much basis for comparison, but these aspects do not appear so different from the Cassin's Vireo below, photographed May 29, 2010 in Harney County, Oregon. The worn plumage is especially obvious in the near lack of wing bars.

Cassin's Vireo: May 29, 2010. Harney County, Oregon. Greg Gillson.

Cassin's Vireo: May 29, 2010. Harney County, Oregon. Greg Gillson.

So, after nearly convincing myself that this bird is indeed Plumbeous, I sent a note to my local eBird Reviewer. "If I changed the vireo," I asked, "from Cassin's/Plumbeous to Plumbeous would it be accepted?" The note I received back from Gary Nunn? "I would lean to Plumbeous Vireo as you pointed out concerning molt and freshness of plumage. Really any Cassin's ought to be brightly colored right now. So yes, change it to Plumbeous Vireo."

Yes! I hate not being able to put a name on a bird.

Philadelphia Vireo at Fort Rosecrans National Cemetery

The Fort Rosecrans National Cemetery [birding site guide here] sits on the top of Point Loma near the end, as this peninsula juts into the Pacific Ocean. Fall migrants, flying at night and perhaps disoriented by coastal fog, often find themselves out over the ocean at dawn. The nearest point of land? Perhaps the green residential area of Point Loma. If they work themselves southward during the day, they'll eventually end up in the cemetery on Point Loma and not want to fly southward over the bay to the low sand spit that is North Island Naval Air Station and Coronado. These tiny waifs will rest, feed, and wait until nightfall to see if atmospheric conditions are right to fly several hundred more miles farther south on their annual trip.

Not every day brings a new set of migrants, but there are at least a few new birds arriving and departing almost every day, all through September and October. On some mornings there is a "fall out" of migrants--that's what you want--the trees dripping with newly arrived birds. Those individual bird watchers who can arrange their schedule to visit several times a week during fall will end up with many migrants, frequently including rather rare birds. In fact, this is the best location in San Diego County for finding rare neotropical migrants--warblers, vireos, flycatchers, orioles, tanagers, grosbeaks, and others.

Thus it was that Gary Nunn discovered a Philadelphia Vireo at Fort Rosecrans National Cemetery on October 2, 2016. [Read about it on Gary's blog here.] It wasn't a very good day for migrants. It was Gary's third circuit around the SE part of the cemetery, repeatedly checking favorite trees, when he struck gold just before 8:00 am. He then announced his find on the San Diego birding listserve.

Point Loma is almost an hour by freeway from my home, so I only visit a couple of times each fall. Fortuitously, I had chosen this exact day to bird in the Tijuana River Valley, and visit Fort Rosecrans cemetery on the way home.

Updated posts to the San Diego birding list indicated the bird had likely flown away, but I stopped anyway. A few birders were milling about the favored Chinese elm that Gary had indicated earlier. "I think I have it!" someone whisper-shouted, and everyone went running. Was that the bird? It kept hiding very well in the little tree. To make matters worse, a very similar-looking Warbling Vireo was working slowly through the branches. But what's that chasing the Warbling Vireo? It looks yellow on the throat and I think it has dark lores. Is that it? Yes! A "life bird"--the first I've ever seen. And photographed to boot.

Philadelphia Vireo. Fort Rosecrans National Cemetery, San Diego, California. October 2, 2016. Greg Gillson.

Renting a boat for birding on Lake Henshaw

This past winter Marlene and I stayed overnight at a rustic cabin at Lake Henshaw. [Read Overnight at Lake Henshaw]

In August some rarer shorebirds were reported at the lake, viewable by boat. So we arrived early on the morning of August 28th and rented a motorboat and puttered around on the large, shallow lake.

The cost for the boat rental is $50 (their website says $35), plus $7.50 per person for lake access. So it was a bit expensive. But Marlene and I had a great time. Birds weren't really afraid of us in the boat. We were limited a bit by shallow water in the southeast end of the lake, but got many photos of the shorebirds there.

We rode around the boat in the morning. Then we stopped for lunch. Afterwards we went around the lake again, but the wind came up blowing us into the muddy shallows and creating slightly rough water, making birding and photography difficult.

So, if you want to spend a couple of hours boating around the lake, my recommendation is to arrive early,... and don't bother if it's windy. For shorebirds, mid-August is probably best.

Looking back at the boat dock at Lake Henshaw.

Great Egret

American White Pelican

Double-crested Cormorant

American White Pelican

American Avocet

Stilt Sandpiper

Baird's Sandpiper

Red-necked Phalarope

Baird's Sandpiper

Stilt Sandpiper

Clark's Grebe

American White Pelican

American White Pelican

American White Pelican

Double-crested Cormorant

eBird Profile Pages

For the past few weeks I have been adding bird photos to my older eBird checklists.

In July I wrote about the new eBird Media Search tool. That allows one to search for photos and audio records that have been added to eBird checklists. It has only been since November 2015 that you could add photos to your checklists. Now, however, a new feature, called Profile Pages has been added to eBird. If a person so chooses, he can add a blurb about himself and make it publicly viewable. It shows a map with the number of species recorded in each country, state, county, along with the bird photos from each.

I knew I have over 325 photos of birds from Oregon, and must be over 200 in San Diego County now. But the eBird Profile pages says I had far fewer photos in my checklists. So I went back to 2002 and added photos to my checklists. I just completed adding all my bird photos to all checklists today. 536 species recorded in the United States, 411 of those photographed. 417 species recorded in Oregon, 336 of those photographed. 334 species recorded in San Diego County, California, 280 of those photographed. Here is my profile page.

My eBird Profile page. From here one can zoom in or out to different world, country, state, or county levels.

Besides the different geopolitical levels you can zoom to, you may also view all their photos that have been added to eBird checklists. IF (a big if, but highly recommended) the photographer has ranked the quality of their photos then you can sort on their best photos, along with newest and oldest. And those choices are also sortable with the zoom to each geopolitical level.

This is a good tool for tracking your own photos and species seen, and also view the same for others.

So how do you find out who has a profile you can view? The best way is to Explore Data, Top 100, and choose the state and county where they bird they most. If they have a public profile page their name will be highlighted as a web link. Click and view!

Like this:

This feature is just getting started. I suspect (hope) that additional tools will be added to the Profile pages. One thing I want is my checklist to note whether I have ever photographed a species or not. That way I can go out and take photos of birds I've never obtained in whatever region I am interested in.

Play around in the Profile page and you can see that the maps change by clicking on "Species Observed" and "Species w/ Photos." Fun stuff!