Sunday, August 10, 2014

Leo Carrillo

It was somewhat nostalgic to hear a family beach trip was being planned today. A few years ago, such a family beach trip found me a rarity in Australia which brought about, in Melbourne's terms, a serious twitch.

Like Mordialloc, there was nothing of interest recently reported (or ever, too be quite honest), but there was something compelling about a bit of seawatching. There was also a hiking trail in the back, though not a long one as I soon found out.

I saw my first breeding plumage Brandt's cormorants today, intermingled with a scattering of pelagic and double-crested cormorants as well. All of the aforementioned birds were located on this rocky outcrop a few metres out to sea. My first surprise was a grey wader that flew by and hopped onto the rocks, a wandering tattler, which was a new tick for me though it did not stay for long. Cruising past the rocks were a few royal terns, a lone caspian tern, the typical gulls and pelicans, and an probably black-vented shearwater that was too far out to identify.
Wandering tattler with double-crested cormorant (left) and Brandt's cormorant (right). Don't ask what
the background cormorant is, no idea!
On the start of the hiking trail I noticed some odd checkered-style butterflies in the genus Pontia. From afar they were just white, nothing more could be seen, but closer to their "flight snapshot" was undeniably odd*.

*(flight snapshot is a term I've developed referring to the "frozen" images you see of butterflies in flight when they are nearby. Presumably because the human eyes cannot detect the swift motion of the butterfly wings in flight properly, there is often some "lag" in what is seen. Such snapshots allow the observer to see "flashes" of the markings and colouration of the upper wings as if it was perched still. Otherwise the blurring motion of white butterflies would be just that, a white blur.)

When they finally landed the mystery was resolved; they were Becker's whites, a very localized species that I had only seen once before. Though similar to both checkered and western whites, the markings, particularly the underside ones, are much bolder and the central spot on the front wings is bigger and wider.

Male Becker's white.
On the sage I saw a fluttery, dull, moth-like...not-moth. It was a tattered Behr's metalmark, a common but localized species in this area that I had not seen before. This is the first time I have ever observed a species of the metalmark family Riodinidae as well, giving me a chance to see their unique behaviour that is not mentioned in textbooks. Apart from their odd flight, they are unique in other ways as well. At flowers they have a specific behaviour cycle, starting with spread wings, with a few wing flaps to about 45 degrees, before completely closing their wings for a few seconds. Then they completely spread out again, and repeat. Most butterflies are quite motionless at rest, so it was odd to see. I saw others as well, and it seemed that the more I saw the more pristine they looked. At first they were a bit tattered, but the final one I saw was very immaculate.


I was able to spot some nice bee flies as well. I usually only see 2 or 3 varieties per outing, but I had at about 6-7 species here, many of which I have never seen before.

One of many bee flies, this one is the relatively distinctive Poecilanthrax arethusa.

At about 2pm back along the coast a "probable feral rock pigeon" flew over my head, easily told from the small, long-tailed mourning dove by its large size and short tail. A few seconds passed and it flashed white in its wings, something not originally visible from the underside view I first observed when it flew overhead. That changed everything; this common bird often considered a pest quickly morphed into a rarity for this area in the form of white-winged dove, a desert bird usually found quite far to the south from here. While rare, multiple records exist of its wandering along this coastline, so it is clearly quite migratory in nature, albeit in the wrong direction. This bird landed on the west cliff, about 2 metres from people on the beach (you bet I wish I was standing there) before flying off around the coastline again before I could walk more than 3 steps.

The white wing patch on this white-winged dove is quite visible even with the naked eye. The long bill (for a dove)
is not seen here but it is obvious in other images.

No, not a bad trip at all. I'm starting to like these family beach trips.

Tuesday, August 5, 2014

Corn Creek revisited

On the annual Las Vegas trip, faced again with an hour time frame in which to visit the local wildlife, I opted again to check out the Corn Creek field station, both a migrant trap and a regular site for a few local specialties. I did not post my last visit, but Corn Creek quickly became one of my favourite birding spots. I like to think of Corn Creek as a bit of a "wildcard", since it is totally random what is seen (and what isn't seen!) on a visit to this location on any given time of the day at any given time. Last visit I found Nevada's 9th NBRC endorsed record of purple martin which was quite something.

It was good to see that the heavy construction setup had vanished, along with the rather obnoxious clamour it threw up if you were standing in the immediate vicinity. In its place was the new (but closed) visitor center, a car park, and toilets, which was exactly 300% more facilities than the last time I visited. There was a fair bit of weather nearby, rain and thunder/lightning, which fortunately had diminished prior.

I first visited the "orchard" area. I don't actually remember this area so I think I missed it last time. There was quite a tremendous amount of activity here, mostly western tanagers but also orioles (hooded, Bullock's) and a lone (but attractive) male indigo bunting. The fence was occupied throughout by about one black phoebe every 10 metres, vigilantly keeping to their invisible territories. I also played an Abert's towhee recording to remind myself of their vocalizations, and was sure I heard a reply far off but I could not be sure. Other than this I did not encounter such a bird during the trip.

For the next few minutes or so I checked up on calls to make sure I knew what I was hearing--Nevada, though it is not too far from California, has a wealth of new possibilities. I was perhaps a bit out of my element here, so I didn't discount a new bird hiding behind a familiar sound. For instance, I had heard a sort of metallic "chik" call; what I assumed was a bunting, probably indigo or lazuli, from within a dense patch of undergrowth nearby a little creek. Wait, dense undergrowth? Buntings live in the open, perched on exposed branches, or even hopping along open grasslands, so this instantly raised a red flag. I took one step and a dark bird dashed out and landed on a branch a couple of trees down the creek. I could see a white supercilium line and pale underparts from where I was standing, the rest shrouded by leaf cover. I thought perhaps it was a black-and-white warbler, a bird that would have those sort of features, but a little repositioning on my part revealed some interesting streaking and a face that looked like it came from a thrush.

It was now very obvious that I had a waterthrush on my hands. The waterthrushes were odd thrush-patterned warblers known for their love of water--a bird that could not be named in any better fashion. Only two waterthrush species exist: the northern waterthrush and the Louisiana waterthrush. So here is what I was thinking right at the time, to give an idea of the situation for a non-birder:
Erm, hang on a minute...Neither of these maps are even close to where I am.
Often in birding the common conundrum is deciding between a regular species and a rare species. Rarely is it that the conundrum is deciding between a rare species and a rarer one! I tested the calls of both species, and it sounded thinner than northern waterthrush.

The bird then, as its habits would dictate, flew into the water of the creek and hopped along the stones perfectly at home. Exposed in the open, the bird really stood out in its high-contrast dark-brown back and clean white underparts. Another feature that stood out here was its rather bright pink legs. Typical of waterthrushes, it flicked its tail regularly at increments of about 7 seconds+. Along with its unmarked white throat and lack of buffy colouring overall, it was quite clear I was dealing with a Louisiana waterthrush, by far the rarer of the two this far west. Update August 5th: this bird was refound by others today and confirmed as the 3rd-4th NBRC record, what a great bird to find.

A bit lost would be a bit of an understatement I'd say, though Nevada
does seem to be a bit under birded, so perhaps it is more common than it is thought.

In other parts of the park I located a Virginia's warbler foraging silently in some low trees. This is a mountain species at this time of year so here in the low desert it is another good bird but not necessarily rare. I did not have any luck with Lucy's warbler at the site. I picked up 2 black-throated sparrows on my way out of the park and along with 2 loggerhead shrikes on the drive out, this concluded the visit. I definitely do not regret coming here.

Virginia's warbler. The diagnostic yellow undertail is only just visible through a gap in the leaves.

Black-throated sparrow