Loading ...
Sorry, an error occurred while loading the content.

15776What is true spring status of Plumbeous Vireo in CA??

Expand Messages
  • Barbara Carlson
    Apr 14, 2014
    • 0 Attachment
      Every spring during April there are a number of Plumbeous Vireo reports 
      in coastal southern California and out in the southeastern deserts. 
      Unfortunately, very, very few of these reports are well documented. And 
      whereas this species is certainly a rare-but-regular fall and winter 
      visitor to s. California (very rare to casual in coastal northern CA), 
      that status does not extend to the spring season. And this is true even 
      for the southeastern deserts, much less the coastal slope. However, it 
      appears that the conventional wisdom among many birders is that this 
      species is semi-expected as a SPRING MIGRANT in these same areas. One 
      friend who is the eBird reviewer for one of the southern CA counties 
      tells me that he has received a fair number of reports to review during 
      the past couple weeks (and in previous springs), but very few of which 
      contain any sort of contemporary adequate documentation, and which were 
      often seen by people who failed to appreciate AT THE TIME OF THE 
      SIGHTING how very rare such a bird would be. Some of these reports are 
      from areas where individual Plumbeous were known to have wintered. But 
      many are not. Wintering Plumbeous regularly remain well in to April--at 
      least to mid-April and a few times through late April. And wintering 
      birds can easily be missed earlier in the season, or then turn up at a 
      "new location" in early spring as many wintering birds shuffle about on 
      a local scale in response to shifting vegetation attractability and thus 
      changing food supply.

      This whole situation is made more complicated, of course, by the ease 
      with which some of the duller spring Cassin's Vireos can be 
      misidentified as Plumbeous Vireos--and certainly Cassin's is the 
      expected "Solitary" Vireo during spring in ALL these areas.

      Many spring records of Plumbeous Vireos from a number of counties from 
      back in the 1970s, 1980s, and 1990s are properly being reassessed by the 
      local records-keepers and others. Some are probably now thought of as 
      lingering winter birds rather than true spring migrants, and some will 
      properly be 'let go' as being inadequately documented at the time. We 
      just didn't know back then.... There have certainly been major advances 
      in our knowledge of Solitary Vireo ID and status/distribution over the 
      past several decades.

      Most of the very few "good" records of spring migrant Plumbeous are from 
      May (including on the southeastern deserts), and there is even an early 
      June record from Orange County back in 1993.

      In sum, CAN migrant Plumbeous Vireos occur in spring? Yes. But have 
      they been over-reported at this season? Definitely yes. I guess we 
      should all take one giant step backwards and take extra care in making 
      future spring reports of this species, particularly when the bird does 
      not clearly involve a lingering winter bird.

      --Paul Lehman, San Diego
      Posted by Barbara Carlson, San Diego

      Posted by