Bird News from Nial Moores
Continuing mild with light rain and mist in the morning followed by hazy sunshine in the afternoon and a high of 8C.
With light winds from the east, at least 220 Ancient Murrelet were counted swimming offshore from the park, along with nine Black-necked Grebe, 20 Great Crested Grebe, one Arctic and two Red-throated Loons. Further hints of early spring came in the form of one calling and another singing Yellow-bellied Tit (the latter apparently part of a wave of 350 or so birds, comprised in descending order of abundance of Vinous-throated Parrotbill, Yellow-throated Bunting, Brambling, Eastern Great, Long-tailed and Coal Tits and Japanese Pygmy Woodpecker) and a flock of 15+ Olive-backed Pipit, along with a reduction in Siberian Accentor to just one.
There were two interesting opportunities for looking at ID Questions.
The first question (often asked, including in an email from a North American guller only last week) is how much variation is there in the shade of upperpart grey in adult Slaty-backed Gull (i.e. are there some paler-saddled birds)? I believe there is very little variation, and that much of the perceived variation in saddle-grey is more down to light and angle, with birds seen from the rear tending to look paler than birds seen from the side. Although the images are poor (and our blog does not host high-res images…) two adults roosting on tetrapods demonstrated this well. In heavy overcast and mist, seen from the rear the upper of the two Slaty-backed Gull looked strikingly paler-mantled than the lower bird, but then seen from a different angle (as in the image) this effect was reversed. Much closer, unaltered images of the lower bird as it turned also help show this effect.
The second question is how easy is it to identify male and female Oriental Turtle Dove? Often pairs seem to contain one larger (presumably the male) and one smaller bird. On this day, a male gave one “song” phrase, and a female responded immediately, flying next to the male and flattening herself next to him. Copulation followed soon after, and the female then remained in the same spot with the male next to her, both dozing and preening. At least in this pair, as presumed the male was substantially larger than the female. Moroever, the male had cleaner, more contrasting grey on the forehead; had obviously darker and stronger rust-rufous fringes to the tertials and scapulars (many of which looked paler-tipped in the female); and some of these broadly rust-fringed feathers had black centres that terminated in a narrow point, which in this particular fenmale were less obvious. Are such male / female differences consistent?