ML318628041

Age

Not specified

Sex

Not specified

Observation details

Pair: The Male is considered Mexican and the female is considered Mexican x Mottled. Male: Features consistent with Mexican Duck: 1) Minimal dark spot at bill base; 2) Significant white edges around the blue panel, too broad white for Mottled; 3) Eye-line length similar to Mexican; 4) Heavy streaking on cheek with contrasting plain pink throat; 5) dark black crowns. The apparent coloration of the face on this bird varies with lighting. In direct very bright light, the face appears striated with buffy under color like a Mottled Duck, which caused us to initially consider this as a MEDU x MODU hybrid. However, in good but indirect light, as documented on subsequent days, the face appears darker and striated, more like various reference photos of Mexican Ducks, including photos I have seen from Leukering, Mlodinow and Ebird. It looks like Mexican ducks I have seen in El Paso, including the cheeks. Today's pictures were in the very direct bright light, and cheeks appear darker in the photos from 3/23, and 3/24, which are the same birds. Our reviewer, John Berner, kindly sent these photos to two experts on this topic, Steve Mlodinow and Jack Bushong. We appreciate the effort they put into looking at the data and commenting. After some discussion, and after looking at more photos taken on subsequent days, the consensus is Mexican Duck for the male and probably Mexican x Mottled for the female. Jack's comments on the male: "As to the male, it's likely a pure MEDU. Hard to definitively rule out any MODU influence but these new pictures (referring to the pics by several people on the 24th-26th) show broad white borders to the speculum (unlike the female....), a lack of any noticeable gape spot, and fine gray ticking on the face. The face is slightly paler and cleaner than expected for a MEDU ....However this paleness is probably still within the spectrum of natural variability for MEDU." Steve's comments on the bill: "The black at the gape is limited to the bill as far as I can tell, and does not actually involve the feathering. Mottled Ducks can have this pattern, or a spot of black feathering at the gape. Mexican Ducks can have a bit of black on the bill at the gape (not nearly as commonly as in Mottled Duck), as this bird does, and do sometimes have black feathering at the gape as well, though Mexican Ducks with black feathering at the gape have it as part of a thin line that extends down from the eyeline (different from the pattern in Mottled). " And later... "I'm fine with straight up Mexican." Eric Carpenter of the TBRC has concurred. John Berner suggested that I add Eric's comment: "I don't spend a lot of time with this complex of ducks, but it does seem like the one bird is a pretty great fit for what I see in photos/references as to what a male MEDU should look like. Perhaps it has other parentage in it but I don't see any hint of plumage that is obviously something different....Ignore the behavior I'd say - accept it in eBird as a Mexican Duck based on plumage. I think that is what eBird central would want you to do." Location southern shore, east side by water pipe 29.909885, -95.677315 If you chase this bird, be careful to find the same one as there are three similar pairs on the lake. (If you see significant green sheen you are probably on the wrong bird) This is the first accepted report of Mexican Duck for Harris County.

Technical information

Model

Canon EOS 7D Mark II

Lens

EF100-400mm f/4.5-5.6L IS II USM

ISO

800

Focal length

234 mm

Flash

Flash did not fire

f-stop

f/6.3

Shutter speed

1/1600 sec

Dimensions

5472 pixels x 3648 pixels

Original file size

5.44 MB