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Sunday, August 14, 2011

Yellow-bellied vs Red-naped Sapsucker

Male Yellow-bellied Sapsucker
     My son Bryan was trying to identify a sapsucker in Illinois while on a bird walk. Some folks believed it to be a Red-naped Sapsucker. He argued that it was a Yellow-bellied Sapsucker. Here is what he wrote up after that bird walk. 
After a little scouring of the internet and a brief glimpse into my library of books, I have found a little bit of information that can help us in this ID challenge.  I would love to see some discussion on this topic, but I think the local birding community (including myself) lacks enough experience with Red-naped Sapsuckers making this discussion a little tougher.  Feel free to prove me wrong.

YBSA adults:
Males should be easily identified by their red-throat with complete black border or frame (completely black malar stripe lacking any red) as well as a distinctly spotted back pattern (spotted white on black) with the typical sapsucker longitudinal (head to tail) wing stripe of sapsuckers.   The back patterning is of utmost importance when comparing this species with RNSA (of either sex).  YBSA (either sex) shows this spotty pattern on the back as seen in the photos above.  RNSA (either sex) will have another set of longitudinal stripes down the back rather than just on the wing making for four dorsal stripes and the spotting will be minimal.  Although YBSA (either sex) shouldn't have a red nape, males can on rare occasions have red in the nape, making this ID mark unreliable or non-diagnostic at least.  Be sure to check all the ID marks before proceeding on from any questionable birds.

Females should give us no more difficulty when comparing to RNSA.  Females lack the red throat of males, but maintain the same back pattern (spotty white on black).  The throat should be completely white with a black border or frame.  If there is any red in the throat be wary of calling this bird a female YBSA.  RNSA females will have a good amount of red in the throat (up to half the area) but sometimes significantly less coming from the chest making this an easy comparison.

RNSA adults:
Males should have a striking red throat and crown with a red-nape.  The black border of the throat should be incomplete as it is invaded by some of the red from the throat.  The incomplete border should almost clinch this ID, but a good look at the back should be had.  The spotting on the back of YBSA should be replaced by longitudinal stripes (consisting of nearly overlapping white spots).  Again let me re-emphasize that the red nape DOES NOT clinch the ID of this bird. 

She is a tough one to tame.  I cannot find many images of female RNSA that were showing all the things necessary for ID.  This is strange to me as there are plenty of photographers in the inner mountain west that should be seeing these photogenic birds rather often and in nesting times.  The throat should have up to half red and half white with a black border that is likely to be complete as the male RNSA incomplete border is due to the complete red throat invading the black border.  This sex can be confused with the male YBSA.  Without a good look at the throat, one could theoretically confuse this bird with a male YBSA.  However, to make this easy, look at the back.  The back patter of RNSA females is the same as RNSA males, and it drastically different than YBSA.  This is the same as the other discussions.  Always look at multiple ID characteristics not just one.

YBSA Juvenile:
Take an adult sapsucker and make all the black into brown.  This bird will have scalloping on the chest and a medium to dark brown crown.  The crown though has speckling of white making it look slightly lighter and sometimes even grayish instead of brown.  This helps you separate this bird from the RNSA juvenile.  This bird also shows a stronger back pattern than RNSA.  YBSA is strongly barred and spotted with rich buff on black patterns.  As for molt pattern, a YBSA molts in late fall to late winter (sometimes even in March) and molts the crown first, but in a splotchy manner which differs from the molt pattern of the RNSA (see below).  You will sometimes see a YBSA juvenile with splotchy molt well into winter, while you will never see a molting juvenile RNSA in winter. 

RNSA Juvenile:
Another hard image to find on the net.  (Good luck if you try looking.)  This bird is not too hard to identify.  Take an adult female sapsucker (either species) and make it brown.  RNSA juvenile has a medium brown coloration except for on the crown, where the color is dark.  There is no spotting in the crown of a RNSA juvenile.  Here is where it gets exceptionally fun to remember.  RNSA and Red-breasted Sapsucker (RBSA) juveniles begin to molt before migration in fall.  This means that they begin to have reddish color on its crown usually BEFORE migration begins.  Think juvenile with a mixture of adult.  This juvenile that is molting during migration shows red on the front of the crown that grows in with time from front to back.  If you find a juvenile sapsucker in fall migration with a half red crown, it is almost certainly a RNSA.  When you move down the bird, the chest will appear scalloped, but not as scalloped as YBSA.  I don't have any indication of how to tell the difference between rather scalloped and somewhat scalloped, sorry. 

So there you have it.  The skinny and fat of the Sapsucker complex.  For those of you interested, I hope this helps. 

Bryan Guarente

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