Oct 26 (Day 299) - BIG, BIG BIRD news from the Salton Sea!!! Very long entry!

OK, I have to be honest with you. I left a big chunk of what happened yesterday out of the blog for reasons that I will explain. I am actually taking it easy this afternoon (after a nice morning of birding), so I have plenty of time to explain what's happening. 

The reason that I almost didn't find the Yellow-footed gull yesterday was that I got sidetracked by another very exciting bird earlier in the afternoon. Here again, I need to take a step back and explain a bit further. 

In chatting with Paul Lehmann and Guy McCaskie last week, Guy mentioned that he had found a very exciting bird at the Salton Sea last week. For now, let's call it "Z". Many things would have harmonize for me to add Z to the year list this weekend. First, the bird would have to stay put for the intervening week. Second, I would have to find this single bird among the thousands of birds in the area where it was seen (assuming it stayed in the same general vicinity at all). Third, I was going to need a very good look at the bird to identify it. Fourth, given difficulties associated with identifying this species, I would need photos of the bird to run past experts to confirm my diagnosis. Given these parameters, it seemed incredible unlikely that I would be able add Z to my list. However, Z would be a high quality addition, and I figured that it would be a good test of my birding skills to see if I could relocate the bird (again, if it was even present at all)

At this point I will tell you that Z = Thayer's gull. This is a species that, like Ancient murrelet, I thought I would miss this year; I assumed I would be moving south through and out of California before individuals of this species arrived on their West Coast wintering grounds. This bird is rarely seen at the Salton Sea, and most of the sightings are from much deeper in winter. In fact, there is only a single eBird record from the Salton Sea in October and 7 total for Southern California in October.

Thayer's gull records - all months, all years.

Notice, there are ZERO sightings in the last month (no orange pins)

Thayer's gull is a VERY good find down here at any time of year.

Here are the October records. 6 of the 7 pins represent single

sightings of single birds.

From this you can see that adding Thayer's gull would be an incredible win for me. I did have one piece of very helpful information. The bird that Guy found was a juvenile/1st winter bird. This would help me refine my search image to narrow down the birds at which I would have to look. The problem with Thayer's gull is that it is, like most gulls, highly variable in its plumage. So is Herring gull, the much more common bird from which I was tasked with separating the the potential Thayer's.  I headed to the area where Guy reported the bird and started the search after lunch yesterday. Luckily, gulls tend to be very loyal to the areas where they winter, so if in fact this represented the final stopping point for this gull there was at least some chance the bird would be in the area. 

Basically, I was looking at every 1st year Herring gull for a bird that looked a bit smaller, and had a  more rounded head, a smaller beak, and lighter primaries. I spent about 45 minutes trying to turn each Herring gull into the Thayer's without success. Eventually I noticed an interesting bird sitting by itself on a little rise out in the water. It seemed to meet the criteria above, so it had my attention. Just as I got excited, the bird flew about 15 feet, and in so doing, revealed its pale upper/underwings. I was sure this had to be the Thayer's as the paler wings are a really good field mark for separating this species from Herring gull. However, given complication surrounding the ID of this bird, I really wanted to get upper/underwing shots of this bird to show experts and to please blog readers. After it flew, the bird landed on another little island that I could not approach closer than say....100 feet. I tried to get the bird to fly by jumping up and down on the shore. I tried, yelling, clapping, and arm waving. Nothing would spook this guy. I resigned myself to waiting for spontaneous flight. I stood with camera at the ready; I would get only one crack at this. Luckily, I only had to wait about 20 minutes. The bird flew directly away from me, but I managed both my upper/underwing shots that were enough to convince all local experts to whom I sent them. After getting confirmation from these folks, Thayer's gull will be entered as year bird #581. This bumps Yellow-footed gull to #582! WOW WOW WOW! If you would have told me that I would get both Ancient murrelet AND Thayer's gull at the latitude of San Diego in the same week in October, I would have told you to put down the crack pipe!

The bird was craning his neck up in this shot. Most of

the time he looked much squatter (i.e. shorter necked).

Small dark beak, smallish round head, dark brown 

primaries - check! As one expert noted, "This is a 

first winter Thayer's gull retaining some juvenile 

plumage in the coverts as is typical in early winter"

No black in primaries like a typical Herring gull.

No levels adjusted on this image - right out of camera.

Pale underwing too (see right wing).

This is the next frame from the above

shot, but I added some light in post 

to show the underwing better. 

This is why the image is much lighter even 

though the frames are consecutive.

Hopefully you understand why I omitted this from yesterday's entry. I really wanted to be sure before I added this bird. I had seen enough to convince myself that this was a Thayer's, but I really wanted to have the evidence to convince blog readers and experts. This is an example where having photos really, really helps my cause. I did not feel terrible about my failure to photography Yellow-footed gull from yesterday since its a fairly easy ID (more on this shortly), but for these tougher birds, I want to show you that I am doing everything I can to properly identify birds and make my photos available so that others can corroborate. I have to be very mindful of observer bias (i.e. it's easy for me to see what I want to see), and getting photos really helps me stay honest. For example, I clearly was not able to photograph the putative Manx shearwater that I saw in La Jolla last week. I got a decent view, but without photos for me to look at in detail or send to experts, there was just too much doubt for me to count what could have been a bona fide Manx Shearwater. 

OK, now for today - finally! I had budgeted 2 days at the Salton Sea, so I decided to simply enjoy a casual day of birding around here. I must confess that despite the associated nastiness, I really enjoy birding at the Salton Sea. There is never a shortage of birds, there are never other people/kids/dogs to scare birds, and rarities seem to turn up with decent frequency. The light is normally very good for photography as well. With yesterday's gull triumphs, I just wanted a low key day of hanging out at the sea. I thought I might be able to add Snow goose, but it appears as though they are a bit late arriving this year. This bird will have to wait until Texas. I did, however, succeed in finding not 1 but 2 Yellow-footed gulls. Although not super close, I was able get a few record shots for you. I will admit that not getting a photo of the bird yesterday stuck in my craw a bit, so getting serviceable shots today was redemption. 

47 mellow, flat miles

Yellow-footed gull A

Yellow-footed gull A after it joined B

As another holdover from yesterday, I also found a few "Large-billed" Savannah sparrows running about on the deck. I managed a good shot of one out in the open.

As for the next few days, I think I am going to head towards Yuma tomorrow. I have not made this decision final yet for one reason: a Rufous-backed robin has appeared for the last 2 days in Twentynine Palms, CA. My head tells to me to ignore this bird, but my heart tells me to chase it. The problem is that Twentynine Palms is 150 miles from here by bike. It is also in exactly the opposite direction that I ultimately need to go. It is northwest of here, and the wind will be from the W/NW the next 2 days. This means it would be at least a 2 day ride to get to the area, and likely another 2 to get back on track. I am not sure I want to push 4 long days into one bird. Missing it would be a complete disaster. Given how well I have done in the last 2 weeks, I can say with confidence that as long as I make it to the Rio Grande Valley, I will most certainly reach 600 species for the year. I will even go so far as to say that 605-610 is distinctly possible. Riding an extra 250-300 miles for this one bird might actually decrease my chance to reach 600-610 since it increases the chance that something could go wrong with the bike or my body during the long, hard, remote ride. These 250-300 extra miles represent ~10% of the total distance I will likely ride between now and the end of the year (assuming 1,500 miles/month or 50/miles a day. My average for the year right now is 48 miles/day). I guess I feel a bit like the investor shifting his money from growth stocks to dividend-yielding stocks as retirement approaches. Right now the most important thing is to get my species and finish in one piece. Then again, the robin would make for a hell of story!