Wednesday 11 June 2014

Yellow-bellied Sapsucker x Red-naped Sapsucker

Yellow-bellied Sapsucker x Red-naped Sapsucker hybrid, Chico Basin Ranch, El Paso County (Colorado, USA), 2nd October 2013 - copyright Steve Mlodinow
(photo ID: 1152)


Here is Steve's commentary on this bird:
"Depending on what one focuses on first, one might initially conceive this bird to be a Yellow-bellied or a Red-naped Sapsucker.  This bird is clearly at least partly in juvenile plumage and has rather bright buff on the back, which would seem to indicate Yellow-bellied Sapsucker.  However, the markings on the back are on the narrow side for a Yellow-bellied Sapsucker and even more so for a juvenile.  The throat seems adult-like, and very much like a female Red-naped Sapsucker and there is that touch of red on the nape (visible in field in 1-2 % of adult Yellow-bellied Sapsuckers, but much less common in juveniles).  However, this bird has fairly extensive buff freckling in the dark of the lateral crown border, the auriculars, and the malar (or is it moustachial?) - all typical of juvenile plumage, and especially juvenile Yellow-bellied Sapsucker.  This molt state is actually more like that of a Yellow-bellied Sapsucker than a Red-naped Sapsucker.  In the end, most characters seem in between, and some more Red-naped Sapsucker like, others more Yellow-bellied Sapsucker like... just like one would expect in a hybrid.  The hybrid zone is mostly in SW Alberta, and though the population is small, Colorado would seem a prime area for these hybrids to migrate through/winter in."




Yellow-bellied Sapsucker x Red-naped Sapsucker hybrid (same bird as in photo ID 1152 above), Chico Basin Ranch, El Paso County (Colorado, USA), 2nd October 2013 - copyright Steve Mlodinow
(photo IDs: 1153-1155)


Next up is a museum specimen, collected from outside of the usual hybrid zone.  Steve points out the following:
  • Lack of red on the nape (which is lacking on some Red-naped Sapsuckers in June due to wear)
  • Back pattern more like Yellow-bellied Sapsucker than Red-naped Sapsucker - outside range of Red-naped Sapsucker
  • Intermediate throat pattern
  • Supercilium like that of Red-naped Sapsucker
  • Belly perhaps too yellow for Red-naped Sapsucker during June.   




Yellow-bellied Sapsucker x Red-naped Sapsucker hybrid, collected from Tonasket, Okanogan County (Washington, USA), 10th June 1995 and now at UPS Slater Museum, Washington - copyright Steve Mlodinow
(photo IDs: 1445-1447)



Yellow-bellied Sapsucker Sphyrapicus varius
Red-naped Sapsucker Sphyrapicus nuchalis

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