Thursday, April 26, 2012

Spring Migration Birding

With temperatures creeping above 100 in the past week, those of us along the river here were happy to hear that a front was coming through, bringing possible rain and highs in the 80s.  Of course, there is always a potential for a front like this to drop migrants and make for good birding.

In general, spring migration has been fairly slow along the Bill Williams River this spring.  I've had most of the expected species (including my FOS Hermit Warbler yesterday), but numbers have been fairly low.  My high count of Wilson's Warbler for a survey, for example, is only 15.  Western Flycatchers have been moving through in small numbers, as well.  With reports of dozens of migrants around Yuma and Blythe, we've been eagerly anticipating some real numbers coming through.  With overcast skies yesterday and anticipation of a temperature drop, there was hope for a good day of birding soon (predicted by radar this morning by Tim Schreckengost).

This morning, David and I met Tom Johnson for a morning of birding on Lake Havasu.  We started at the north end viewpoint (which Tom has renamed Cape Havasu, a name I find very fitting), but the wind was gusting so hard it was difficult to stand on top of the hill, let alone set up a scope!  We estimated the swarms of Tree Swallows (2000) and headed to Rotary Park, hoping it would be more sheltered.  There wasn't much on the beach at the park, but the wind turned to rain so we were able to amble around the park and look at (soggy) migrant Passerines.  It was a good thing we did, as there were plenty of birds to see, including an estimated 60 Wilson's Warblers.

With some signs of movement in Lake Havasu City, we decided to head down to the Bill Williams Delta to look for waterbirds.  The Delta was slow, but we did have some lingering Greater Scaup and the continuing male Surf Scoter.  Before long, the rain stopped, and we felt inspired to continue further south.

After the customary stop at Ruperto's in Parker, we arrived at 'Ahakhav Tribal Preserve.  We checked out the park area, typically the best spot at the preserve for migrants, and were not disappointed.  A good variety of migrants was present, including about 11 Empids and eight species of warblers (about 60 were Wilson's and 15 were Nashville).  As we were walking out of the park I stopped to look at a hummingbird, and immediately called David and Tom to check it out, as I knew from its buffy underparts that it was something good.  At first I thought it was a Broad-tailed Hummingbird, but was not disappointed when I realized it was a Calliope Hummingbird!  A county bird for David and I, which Rosenberg et al. list as rare and irregular in the LCRV.  Naturally, it flew away as soon as I called out "Calliope", and was not cooperative in allowing more good looks.  Eventually, while it was skulking in a big mesquite, David got a look at it sitting next to another small hummingbird--amazingly, it was another Calliope!  We all got looks at both birds, and 'Ahakhav lived up to its reputation as a magnet for rare birds.  Check out the eBird list for our full bird count.

Calliope Hummingbirds (note difference in throat patterns).  Photos by Tom Johnson.
On our way north, we passed by Parker Oasis, and at first were thinking of passing it by.  David decided to stop briefly just to see if there were birds around, and good thing he did!  As soon as we pulled in, we saw dozens of warblers flying between trees.  After 45 minutes picking through warblers and other migrants, we estimated there were 150 Audubon's Warblers and 100 Wilson's Warblers in this small patch of habitat!  Six species of flycatcher and of swallows, nine species of warbler and others.  No rarities, but it was an exhilarating stop with migration in full swing!  Check out the eBird list here.

We then birded our way north along the California side, not running into any more huge numbers but finding decent numbers of migrants at Quail Hollow and good shorebird habitat (but low diversity) at Emerald Cove.

With this weekend's upcoming AZFO Expedition to the Big Sandy Wash and several more weeks of surveying in the Bill Williams ahead of us, I'm excited to see what will happen next!

1 comment:

  1. That's awesome Lauren, in a truly literal sense of the word. Such big numbers of birds out's jaw-dropping.

    Here in the Valley I'm feelings great to see 3 Wilson's at one site. Congrats on those Calliope too--most excellent. This Havasu area looks and sounds so dynamite for birding, but it's a tough call to drive 3 hours west or 3 hours south to Patagonia. I need more 3-day weekends.