(Credit: U. S. Geological Survey)

Wilson's Storm-petrel - Oceanites oceanicus

Identification Tips:

  1. Length: 6.5 inches Wingspan: 16 inches
  2. Sexes similar
  3. Pelagic bird only coming ashore to breed
  4. Medium to small storm-petrel
  5. Dark bill with tube on top
  6. Very dark plumage
  7. White rump patch, undertail coverts, and flank patch
  8. Gray carpal bar
  9. Yellow feet sometimes protrude beyond squared or rounded tail
  10. Often patters its feet on water surface
  11. Size and flight style reminiscent of Purple Martin

Similar species:

Purple Martin is vaguely similar but lacks the white rump patch and doesn't usually occupy the same habitat. Shearwaters are much larger. Other storm petrels are very similar. Black, Ashy, and Least storm-petrels lack the white rump. Wedge-rumped storm-petrel is smaller with a larger rump patch. Band-rumped and Leach's storm petrels are larger with different flight styles and their feet don't protrude beyond the end of their tails. Leach's has a forked tail and a divided or absent rump patch. Band-rumped has a thinner rump patch.