Hi Tweets

Jeff Gibson writes: "Mew Gull's don't seem to like parking lots...Mew's
just don't seem to be the parking type."

In Vancouver BC, Mews actually do. Well, concrete, if not parking lots.
They stand, walk around and roost on any given day on the concrete apron of
the outdoor Kitsilano Pool, which is unused by people between September and
May, and fenced off from the general public, so no off-leash dogs either.
Kits Pool is a great place to study gulls, their behavior and their
plumage differences and changes, and easily accessible (the 22 MacDonald
stops almost right beside it). Unless, as today, a hailstorm clears them
all out.
On a typical winter day in the pool, there can be 50-200 Mews, 20-30
Glaucous-winged X Western ('Olympic') Gulls of all ages, 5-10 'classic'
GW's of all ages, the odd adult Western or two (often arriving at the pool
in October-November), 10-30 Ring-bills of all ages, 1-8 Californias
(usually adults or Second Cycle, sometimes juveniles) depending on season,
and individual Thayer's and Herring drop-ins, often as juveniles in very
late summer and early autumn, sometimes as adults later on. Plus, every now
and then, rare individual hybrids besides the Olies---GW X Herring, GW X
Glaucous, Herring X Glaucous---and sometimes some god-only-knows-what First
Cycle beast). In twelve years of periodically checking out this day-roost,
sometimes on a daily basis, I've never seen a tern of any kind there;
likewise, Heerman's, Bonaparte's and Franklin's Gull have also been
no-shows.

Dennis Paulson writes: "One reason might be because Mew Gulls are deathly
afraid of the larger species. It is a rare roost, in any habitat type, that
contains both Mew and Glaucous-winged. For years I have been looking for a
photo op of both of them standing together, and it still hasn't happened. I
don't know if big gulls would actually try a predation attempt or if they
represent a source of potential kleptoparasitism that is so guaranteed that
the small gulls just stay away from them. I don't even have a photo of the
two flying together, although I've been alert for that as well."

If the Mews are deathly afraid of the big guys at Kits, they hide it well.
All these gulls typically---given they're gulls and so given to evil
temper---are remarkably relaxed with each other (cue the inevitable jokes
about BC Bud, Canada and the United Nations), and intermingle and snooze
with a minimum of nastiness. When there is conflict, it's almost always
dominance politics (very rarely coming to actual physical conflict beyond
biting the lower-status bird's butt as it tries to get away), some
big-on-little species spatial or I-just-don't-like-your-stinkin'-looks
bullying and intra-species spatting. I've never, not once ever, seen a
GW/Olie predatory grab on a Mew in or out of the pool; in fact, the only
carcass I've ever noted there was of an adult GW that showed no obvious
trauma and could have just keeled over from illness. Incidentally, the best
place to see Mew and GW/Olies's in flight, kinda together, is the viewpoint
overlooking Burrard Inlet at the N end of Trafalgar St. at early evening,
when a few Mews and a lot of GW's are flying west along the shoreline to
their evening roost on the water off Bayswater Beach, and they pass by
close to the viewpoint.

And I can't imagine any GW/Olympic kleptomugging a Mew Gull, unless it's on
a radical slimming diet. If Mews are surface pickers, wouldn't their
pick-up be far too small to interest a larger gull? Yo! Mew Gull! Gimme all
your copepods! Nahhh, that's more work than pay-off.

In light of Dennis's observations, the distribution of the species at the
pool is interesting. The pool itself is a long narrow east-west rectangle
with wide concrete areas at the west (deep) and east (shallow) ends and a
narrower concrete border along the northern and southern sides; only the
southern edge ramps gradually into the water. The gulls prefer the east end
of the pool (the ducks don't care, they're all over the pool: Mallards,
American Wigeon and Bufflehead; sometimes there's a few Hooded Mergansers
and Common Goldeneye, and once a large squad of male Long-tailed Ducks
chatting up a get-lost-you-jerks uninterested female). Looking east (the
blue building is a bit of the Kitsilano Showboat stage, where wonderfully
cornball old-time performances of amateur groups singing and dancing take
place on warm summer evenings), this photograph of the eastern end of the
pool shows a few gulls hanging about:
http://www.worldisround.com/articles/330846/photo6.html It's taken in
September, I'm pretty sure, and shows some gulls---GW's, California and
Ring-billed probably, with some juvs---already utilising the pool as a
rest-stop.

How the species sort themselves depends on what they're doing. Washing, the
larger gulls hog the center of the pool with the smaller ones off to the
eastern peripheries. Socialising---trying to intimidate each other seems to
be the beginning and end of gull socialising---finds the Olympics and GW's
plus Ring-billed and a few California and Mews along the southern ramp and
out on the dry concrete. Actually roosting, the Mews and Californias use
the northeastern and eastern end exclusively in what often looks like a
pure-flock distribution but actually has a few GW's and Olies mixed in,
especially along the water's edge of the concrete (so they can topple into
the water with a minimum of walking, the indolent louts), with Mews and
Ring-billed mixing along the southeastern bit. The southern platform is
sometimes a free-for-all, sometimes reserved for Olies, GW's and
Ring-billeds, as the big gulls' moods take them. A few Mews roost along the
north side, but it doesn't seem to be a regular thing.

So, what makes the Mew Gull behavior and tolerance at the two sites so
different?

best wishes

Michael Price
Vancouver BC Canada
loblollyboy at gmail.com
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