Hayle Estuary gulls, 23/1/15- 20/3/15
I only failed to visit the estuary twice during this period. I'm not particularly proud of the fact and at times it was more like a punishment than a privelige, but as this was not a good winter for Arctic gulls in the South West I probably shouldn't complain! Twelve species were recorded ( not including the possible 2nd w. smithsonianus) plus three "sub"-species (including kumlieni) and possibly one other "form" in the shape of apparent "Atlantic"/"Western" Yellow-legged Gulls (i.e. not "nominate"/typical Mediterranean michahellis). These were complimented (or tainted depending on your point of view) by a seemingly endless procession of hybrids and freaks which meant hardly a day went by without some fascinating i.d. challenge (or total ball-ache depending etc etc). The full list is below- note this only includes birds recorded by myself or birds I have seen photographed during the period;
Black-headed Gull L.ridibundus- max.flock 500+ (estimate- no counts during peak in Jan.)
Mediterranean Gull L.melanocephalus- max flock 60+ (160+ recorded earlier on Carnsew Pool)
Common Gull L.canus- max flock 45
Ring-billed Gull L.delawarensis- 1 1st w. 1ad. w. (bird first reported from Marazion)
Herring Gull L.argentatus argenteus- max flock c.1500 (estimate)
L.argentatus argentatus- max"flock" 3, est.8 individuals during period
(American Herring Gull L.smithsonianus- 1 2nd w. prob. this taxon)
Lesser Black-backed Gull L.f.graellsii- max flock 1265 (prob. exceeded during "passage" days)
L.f."intermedius"- max flock 180+ (no distinction made here between
"Dutch intergrades" or pos. Scandinavian birds)
Yellow-legged Gull L.michahellis- max "flock" 4, est. 13+ ind. only c.3 of which app. "nominate"
type (see section on Y.l.g. below)
(Azorean Yellow-legged Gull L.(m.)atlantis- 1 2nd w./s. showing some characters of this taxon)
Caspian Gull L.cachinnans- 1 1st w. 1 2nd w./s.
Iceland Gull L.glaucoides- 1-2 juv. (no images to confirm ind. i.d. others reported but see below)
L.(g.)kumlieni- 1 (2?) 2nd w. 1 ad. w. (1 juv. photographed). Given the remarkable
fact that this taxon outnumbered glaucoides locally I am reluctant to
believe records of the latter without photographic support!
Glaucous Gull L.hyperboreus- 1 juv (1 other juv reliably reported)
Great Black-backed Gull- max flock 600+ (estimate)
Kittywake R.tridactyla- 1!
HYBRIDS- Lesser Black-backed x Herring- max "flock"4, est.12 individuals (i.d. contentious- see
hybrid section below)
(Lesser Black-backed x Common- ad. showing pos. mixed characters- see hybrid section)
(Lesser Black-backed x michahellis- ad. showing mixed characters- " " " )
Herring x Glaucous- 1 1st w. 2 2nd w. showing mixed characters, but pos. "back-cross"
H.xG. x H.- see hybrid section
Herring x Great Black-backed- 1 juv-1st w. probably x L.a.argentatus
Glaucous x Great Black-backed- 1 juv- 1st w.
I will treat most of the above in separate sections to follow but a few things are worth noting here; the remarkable fact that Kumlien's (Iceland) Gull was the most numerous "white-winger" during the period (if not the whole winter!) on the Hayle, the increase in LBBxH hybrids despite my total failure to find apparent 1st w./2nd cal. birds, the first long-staying/overwintering records of cachinnans for Cornwall I am aware of (not that I am likely to take too long researching this), and the almost distressing number of hybrids and freaks in general! The latter could simply be explained by the relatively poor showing of the "better" species over the last 3 months meaning I often had to scrape the larid-barrel or hammer birds into something vaguely/arguably interesting to try to justify the rail-fare and time spent (or wasted) freezing my bits off at what purports to be an RSPB reserve- without so much as a wattle-screen to shelter their members (or mine) or the interested public!
