I have been getting other opinions and there is a definite consensus the streaking is an artifact of the bird being wet.
If the dark legs are due to mud discoloration that would remove IMO any objection for a MacGillivray’s.
From: <sbcobirding...> [mailto:<sbcobirding...>] On Behalf Of Mark Holmgren <maholmgren33...> [sbcobirding]
Sent: Thursday, September 07, 2017 4:04 PM
Subject: [EXTERNAL] Re: [sbcobirding] Newport and Coronado
I think this MacGillivray's Warbler just got into someone's bird bath.
We paid brief visits to the Newport crossing and the Coronado Seep this morning. Newport was not very birdy, but what we took to be a dove turned out to be a White-tailed Kite when we looked at the picture, so that seemed a bit unusual.
At Coronado there were only a couple of warblers, a first year Wilson's and what we took to be an Orange-crowned Warbler. The Orange-crowned seemed unusual in that the head was mostly gray and the breast was flecked with little black streaks. A picture of the warbler is on the checklist: