Wednesday 4 March 2015

Another Hybrid Diving Duck

Ever since last October I've been keeping my eye on one of the local Tufted Ducks. It had a noticeably large white area at the base of its bill, the tuft was more of a bun, and it seemed to have a subtle peak to the rear of its head - all suggesting some Lesser or Greater Scaup ancestry.

I got some decent photos of the individual in early February and only just today had a chance to review those photos. That in combination with Sir Edmund's report of a hybrid TUDU x Scaup to eBird last week made me review my photos more in depth.

Here's a photo of her from January 19, 2015:

And another from February 16, 2015:

The tuft, although present, is notably short. I liken it to a bun, whereas in a normal TUDU the tuft is more of a pony. This birds tuft has a more abrupt end, but it is thick/full. The female Tufted Ducks have a tuft that is longer but appears thinner.

The head shape of a female TUDU is rounded at the back of the head - the presumed hybrid duck has a subtle peak to the rear of the head. The tuft conceals the head shape though making the peak difficult to discern. That in combination with the large white area at the base of the bill lead me to believe that one of its parents (or grandparents) is a scaup. None of the other TUDUs have such a large white area - it is definitely an outlier, especially at this time of year.

Also note in the photo above that the back is slightly lighter brown in coloration in comparison to the TUDU that is in the background. This is the only photo I have that shows this, so it may be an artifact  or illusion due to lighting - but it was consistent in the series of photos from that day.

Deciding whether it is a hybrid with Greater or Lesser Scaup isn't so straightforward. But the apparent peaked head would suggest a TUDU X LESC hybrid.

The truth is that this bird was here last winter too. And at the time I thought it was a hybrid but never really kept track of the bird. I also remember some talk about a similar bird in the previous winter and managed to find some photos of it here. I'd say that it probably is the same bird and now has spent at least 3 winters in St. John's!

The odd female Tufted Duck does have some white at the base of the bill (see photo below), but it is always more limited. This photo shows the extreme of what I have seen in Newfoundland:

Some other random photos from the last few weeks:
^ note the lack of snow! Taken on Feb 16!

Common Gull and Ring-billed Gull: 

A Northern Shoveler seen today near St. John's: