Presidio highlights and storm petrel description


Josiah Clark
 

Yesterday as part of the Christmas bird count several of us broke into groups and in the  time honored tradition, covered the presidio and surrounding areas as best we could.
  We tallied 109 species in the end, and were pleased to find good numbers of sparrows (700+), Hummingbirds and yellow-rumped warblers at many spots. Over 60 Snipe at Crissy Field, including some on the lawn was remarkable. Also a sora there and 3 snowy plovers in the shorebird protection area. 
 Five white throated, 7 Savannah and as many Lincoln’s sparrows, several varied thrush, over 100 pine Siskins, 600 brandts cormorants, a red-necked grebe off baker beach refound by David Wimpheimer were other highlights. 
Andrew Mcgann found a hybrid  red-breasted Red-naped sapsucker. Also we refound the least flycatcher but couldn’t find the other rarities there.
Not sure if anyone counted the birds by Alcatraz, but there was a massive feeding frenzy of gulls and cormorants out there.
   The biggest surprised happened to those of us at Crissy Field, where while scoping the frenzy of birds a fast flying, all black bird entered my view much closer to shore. At first I thought it was a black oystercatcher and was pleased because that’s rare in the area. But as I got the bird into focus quickly realized it was a storm petrel(!). It had deep rapid wing beats like a shorebird, (not shallow like say a bat or swift) a very direct flight and was relatively heavy bodied for a storm petrel. Especially compared to ashy and fork-tailed storm patrols which I have seen more recently than this SoCal pelagic species.
With some quick directions and luck several people got on the bird as it passed by the lagoon outlet, at that point it was about 100 yards offshore heading straight on for the gate. 
 All that got on the bird with binoculars said one thing that was clear is that the bird was truly black, not gray and had no white anywhere. The dark underwing and forked tail was also noted and eliminates some similar species. 
 As I followed it for nearly 5 minutes in the telescope I eventually noticed it did have a subtle brownish  “M” shape on the carpel bar  as it flared up out of its direct flight  and then landed on the water. When it sat on the water it had a notably long tailed look, with its tail held far above the water to keep dry and its head in a distinctive upright posture.
I eventually stopped watching the bird AZIT near Kirby Cove. It did not fly straight out to sea you but rather flew around in the channel feeding. I suspect it may have been sucked into the bay on the big tides as happens to other seabirds.
The much rarer but similar Markham’s Petrel is similar in size and flight. However this species really shows quite a bold brown carpel bar, which my bird did not have.
Any storm petrol in the bay especially this time of year is remarkable. The more I look into it the more confident I am this was a black storm petrel. However understand it may likely have to go down as a storm petrel species without photos. 
    It’s too bad no one could get photos but not at all surprising as the bird was moving so fast.  Honestly it’s almost unbelievable  we connected with it at all.
   

Josiah Clark | Habitat Potential | Consulting Ecologist | 415.317.3978
License #1043929

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