A grunting finch?

Richard Bradus

Hi all

I spent a bit of time around noon enjoying this lovely day at the East Wash, where I saw multiple FOF for me (including Fox Sparrow, Hermit Thrush and Flicker) but was also completely stumped by a bird making a call like none other I've heard.

I first heard it deep in the fennel/reeds on the upper west slope of the wash along the paved path next to the golf course - a kind of deep guttural "wonk", single call, repeated at rather long intervals a couple of times. Eventually the bird popped up atop the dry stalks, seemingly foraging along with a flock of House Finches, where I saw it make that same deep call once again. While it perhaps could have been an odd female Purple Finch, my first thought was not of a finch but of an abnormally large juvenile/female (Indigo) Bunting, as it had a relatively pale streaked breast, brown head with a not very prominent superciliary line, and a paler throat with a somewhat distinct pale gray/tan band extending around the neck toward the back (but I never got a look at the back or the under tail). However, it had a stout beak, but not huge, and the overall coloration was not as bold (especially around the head) as I would expect for a female Black-headed Grosbeak. After about 30 seconds of a relatively good frontal look, it flew off upslope along with the House Finches and I did not hear or see it again.

I couldn't put the various features together into a cohesive whole in the field, and I can't find a good match in my guidebooks - it actually looks most like a cross between a female bunting and juvenile Spotted Towhee as seen in the illustrations for the third edition of the National Geographic guide (but not like those in Sibley). And, most importantly, that low grunt of a call, so unlike the melodious tones I expect from a finch or grosbeak - more fitting a corvid (raven especially).

So, I'm wondering if anyone has heard a call like that before (dang, sure wish I had thought to whip out my phone to try to get a recording; too late!), or would like to hazard a guess as to the ID. Is it something weird, or just a typical species that I'm blanking on because of its unusual call? Any thoughts welcome.

Richard Bradus
San Francisco