Like Diann MacRae, we have lost the Violet-green and Barn Swallows
and Vaux's Swifts that we would see just about daily over our house
when we first moved in here 15 years ago. I occasionally see all
three species, but very infrequently now.

It's worth considering that these species have declined (also)
because of loss of nest sites or nest material, subtle but continuous
changes that would be very difficult to monitor (just like insect
abundance). Violet-greens need crevices - maybe there are fewer all
the time. Houses are being replaced by condos, which perhaps are very
well sealed against the outside world, as are the houses being built
currently. Barn Swallows need mud, as well as ledges, and I've often
thought that mud is surely declining in urban areas, as our
surroundings are tidied up. I think both of these species have
declined all over Seattle since I've lived here. Vaux's Swifts need
either snags or chimneys, and the former may well be decreasing,
especially of the size needed by the swifts, while fewer and fewer
chimneys may present nesting opportunities because of the way they
are constructed.

It's fascinating to read the accounts of insect abundance by
different contributors, reporting disappearances, declines,
abundances, "too many." I would say that insects have not changed in
abundance in my yard in 15 years, but there weren't many to begin
with. Because of my long time spent in the East, as well as recent
visits in summer, I will reiterate that "bugs" back there are 10x as
abundant (and at least several times as diverse) in forested habitats
as they are in forested habitats in the western Washington lowlands.
In any little sunny clearing back there, you could catch or
photograph insects for several hours and not begin to exhaust the
species present, whereas around here I see the same small number of
species again and again. I see in my wooded "natural" yard pretty
much the same list of 30 or so insects and spiders that Christine
Southwick reported in her Shoreline yard (and thank goodness there
are at least that many), but I consider it a woefully inadequate
representation of biodiversity, when you realize there are 91,000
described species of insects in the US. I'm sorry I haven't had the
time or foresight to make a continuing collection of all the insect
species in my yard, and that would be a great project for an urban
entomologist anywhere.

But that's a digression; the same things are happening continentwide
and worldwide. Basically, we're making the world worse for birds and
other wildlife, except for a select bunch of species that are
adapting very well to the conditions we create as we destroy natural
habitats and replace them with human habitats. If we understood all
the variables, what we see happening is probably quite to be
expected. It should be relatively easy right now to predict which
North American birds will still be common in 50 or 100 years!
-----
Dennis Paulson
1724 NE 98 St.
Seattle, WA 98115
206-528-1382
dennispaulson at comcast.net

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