Thursday 17 March 2016

Three Common Gulls in St. John's

Although we didn't quite realize it until this week, there have been three Common Gulls (the European sub-species of Mew Gull) in St. John's this winter. There have only ever been two seen at any one time this winter. The recent closure of the Pier 17 sewer outflow, has made it more difficult to keep track of our local Common Gull population.

Last winter there were 3-4 Common Gulls over-wintering in St. John's. Four individuals were actually photographed together in late March last year, but there's a chance that one of them was a migrant considering that Ring-billed Gulls start trickling back by late March.

These kinds of facts are only of interest to the few hard core gull watchers in town. But here are the 3 Common Gulls of winter 2015-2016 to demonstrate the variation and have a place to look back to when comparing with future sightings.

To start, this is the banded Common Gull. It was banded in St. John's in the winter of 2011/2012 as a second winter bird. That means it hatched in 2010, so it is now in its 6th winter (i.e. 7th calendar year of life).

It has a fairly distinct ring near the tip of its bill.

In flight, we can see a large mirror in both P9 & P10, as well as a small mirror in P8. This mirror crosses the shaft but doesn't quite meet the outer edge of P8.

Bird #2:
The second bird has a similar wing tip pattern, but has significantly brighter yellow legs with no band on its leg.

Bird #2: has a large mirror in both P9 & P10, as well as a small mirror in P8. This mirror DOES NOT cross the shaft so it is limited to the inner half of the feather. There is also a complete dark band across the distal end of P5.

Bird #3:
 Also has bright yellow legs, but not nearly as distinct of a ring near the tip of the bill.

In flight it has no mirror on P8.

Bird #2 has been seen as far away as Kelligrews, a distance of almost 30km from Quidi Vidi lake.