18 March 2012

Study before chasing

I'm terribly sorry if you've been expecting a blog post from me.  It's been far too long since I sat down and put one together.  I'm working on a few book reviews as well so remember to stay tuned....

Now that it's "late" March already, lots of things have been happening around here.  For example, I swung up to the Davis WTP in Yolo County after a Slaty-backed Gull was reported there.

There was already a crowd there looking when I arrived.  They soon beckoned me over to where someone had apparently relocated the Slaty-backed.  They put me on a dark-mantled gull a fair ways out roosting on the rock levee.  

In the few times that I birded at the Davis WTP before, I usually saw one or two Western Gulls.  When they put me on the dark-mantled gull that everyone was calling a Slaty-backed, my number one question was "WHY is this a SBGU and not a WEGU?".  Fair enough, right?  Someone said the bill was too small for it being a Western.  Another person said the mantle was "too dark" to be a Western.  Neither of those field marks really satisfied me, I simply wanted to see the spread-wing to clinch the ID.  Eventually, it did just that:

Cue the problem... the above bird doesn't have a "string of pearls" like a Slaty-backed should show.  Instead, it has white mirrors on P9 and P10, something that seems fine for Western.  As I was finding this out, everyone around me was congratulating themselves on the "great bird".  Even though they were there next to me, they came to the wrong conclusion and were assuming this was the SBGU.  Granted, I'm not there to correct anyone but the whole notion bothered me a bit afterwards.  Now, it's ok if you don't know all the fieldmarks but why would people drive for hours to chase a bird that they're actually unable to identify?  This is a question I've pondered before.  Sadly, I've seen this phenomenon several times, a couple times even from my days in Iowa.  I would suggest studying up so that when you're there in person, you know what to look for.  Sounds logical, right?

I have been checking the Cosumnes River Preserve in recent days to enjoy the many hundreds of shorebirds that are present there.  In fact, I've noted 12 species of shorebirds in a single afternoon.  Can't complain with that.  Here's a typical view (dark and rainy):

In one of flocks was this SEMIPALMATED PLOVER:


I was surprised to learn via eBird that there are only 1-2 other Central Valley records from the month of March.  Sweet.

A bit more common (ok, a lot more common) are the many GREATER YELLOWLEGS:

Another recent arrival have been the WHITE-FACED IBIS.  Here is a back-lit shot:

Cosumnes River Preserve has hosted a pretty large flock of white geese in recent days.  Here is the distant flock getting up:

Upon closer inspection, you can see that this flock actually had 3 species of geese:

Speaking of geese, the other day I was sorting through a flock of GREATER WHITE-FRONTED GEESE when I came upon this weird goose:

Best I can tell, this is a BARNACLE X GREATER WHITE-FRONTED GOOSE.  Weird combo.  More thoughts are welcome if you have experience with this hybrid mix.  Maybe it's a CACKLING X GREATER WHITE-FRONTED GOOSE?


Some of the most noticeable arrivals have definitely been the swallows.  Here are a few species from recent days:

NORTHERN ROUGH-WINGED SWALLOW:

TREE SWALLOW:

CLIFF SWALLOW:

VIOLET-GREEN SWALLOW:


I've also stumbled on more CALIFORNIA QUAIL in recent days than I have all winter.  I won't argue with that.  Here's one just south of town:

I'll admit, I haven't noticed many changes in our local selection of sparrows these days.  Everything still seems to be dominated by WHITE-CROWNED SPARROWS and GOLDEN-CROWNED SPARROWS.  Here is a shot of the latter:

Perhaps the biggest highlight in the last week came during one of my checks of the Davis WTP in Yolo County (the gull spot I previously mentioned).  Even though it was pouring rain, I huddled outside my car and scoped the many GWGU, THGU, CAGU, RBGU, and HERG.  I was hunting for the previously reported ICELAND GULL.  As luck would have it, I spotted it on the rock dike:

You can see that the tips of the primaries look 100% completely white and that the eye is very pale.  Here is another shot of the bird, this time preening (which gives you a vantage point of seeing the primary tips):

So if the wingtips are completely white, one must consider the nominate subspecies of Iceland Gull, Larus glaucoides glaucoides.  Some of the experts around here consider this bird to be of that subspecies.  However, I hadn't seen the bird in flight and my digiscoped pictures were kind of crappy.  Well, things were about to change.  The ICGU, along with a couple other gulls, got up and started flying directly towards me.  In a panic, I tried to get my dSLR before the bird was gone.  I rifled off these shots as it passed directly overhead:

My, what nice white primary tips you have!  Anyway, if this truly is an adult L. g. glaucoides, I was told that it would be the second ever for California.

Here is a map of where I relocated the ICGU:
View Davis WTP in a larger map

In case any of you wish these posts weren't so bird-heavy, I'll end with a mammal sighting.  I was working out at Staten Island when I spotted this NORTHERN RIVER OTTER digging around.  It then proceeded to wallow around on its back!  Must have felt pretty comfortable with me.