[mou] Fwd: Audubon's report on birds in decline (long)

[Jim Williams]

An interesting commentary on the recent Audubon report concerning 
decline of certain bird populations.

Jim Williams
Wayzata, Minnesota

Begin forwarded message:

From: "Barry K. MacKay" <mimus at SYMPATICO.CA>
Date: June 16, 2007 2:11:32 PM CDT

For many years I've worried that "common" birds seem in serious decline 
that
largely goes uncommented on since the species are still seen, and still 
show
up on lists.  I'm not a lister or diarist, so my personal experience 
with
local bird populations here in southern Ontario necessarily are 
subjective,
and yet even in making allowances for the youthful "wow" factor, and the
spread of urbanization, it seems to me that there were just so many MORE
birds of MORE species visible when I was young.

So naturally I am happy that attention is being paid to the matter (and 
I'm
not alone in my subjective impressions...unfortunately it is hard to 
find
"benchmark" data from very far back by which to verify impressions, 
although
I think monitoring is now pretty sophisticated and changes will be more
objectively documented.)

All that said, this article says some things that disturb me, or at 
least
generate questions.

For example:  "Some of the birds, such as the evening grosbeak, used to 
be
so plentiful that people would complain about how they crowded 
bird-feeders
and finished off 50-pound sacks of sunflower seeds in just a couple 
days.
But the colorful and gregarious grosbeak's numbers have plummeted 78 
percent
in the past 40 years."

Forty five years ago we were banding large numbers of Evening Grosbeaks 
in
my grandmother's garden.  They were everywhere.  BUT, they were 
relatively
"new" to the province. I have been researching past population sizes of
Double-crested Cormorants, which has led me to Thomas McIlwraith's
compilation of birds of Ontario, published in, um...MDCCCXCIV.  I think 
we
tend to assume that the late 19th century probably would have been far 
more
"birdy" than, say, the mid-20th, but I am increasingly thinking that 
view is
erroneous...which is a topic for another day!

What he says of the Evening Grosbeak is that it is "...a western species
whose line of travel in the season of migration seems to be along the
Mississippi Valley, casually coming as far east as Ontario.  I have 
heard of
its being observed during the winter at St. Cloud, St. Paul, in 
Minneapolis,
and last winter I had a pair sent me by the mail in the flesh, from 
Redwing,
Minnesota [how's that for superior mail delivery?]."

He talks of some seen in 1871, and then said, "I did not hear of the 
species
again till the 17th of March, 1883."

My point is that bird populations do fluctuate, and there is nothing 
more
"normal" about having so many Evening Grosbeaks that they polish off 50
pound sacks of sunflower seeds, than having to go years between 
sightings.

The article also states:  "Today there are 432 million fewer of these 
bird
species, including the northern pintail, greater scaup, boreal 
chickadee,
common tern, loggerhead shrike, field sparrow, grasshopper sparrow, snow
bunting, black-throated sparrow, lark sparrow, common grackle, American
bittern, horned lark, little blue heron and ruffed grouse."

That's an eclectic admixture, but the one that stands out is the Common
Grackle.  This species is lumped with other Icterids and Common 
Starlings in
the minds of "wildlife managers" and their ilk as being far too common!
They are exempted from protection. Certainly there are not only many of 
them
(to my own joy if not that of others) but their habitat has probably
increased since colonial times (at least if not, the argument...which I
dispute...about "agricultural subsidy pumping up populations of other
species, from White-tailed Deer to Snow Geese, falls flat) and it also 
seems
that their choice of nesting habitat may have broadened since the 19th
century (hard to say).

It states:  "The bobwhite had the biggest drop among common birds. In 
1967,
there were 31 million of this distinctive plump bird. Now they number 
closer
to 5.5 million."

Yep, and yet the wildlife managers will continue to imply they know what
they are doing and that hunting generates revenue helpful to these plump
birds.  One problem with hunting is that it decreases gene pool sizes, 
thus
variability that can better lead to adaptation to changing conditions, 
such
as climate, invasive species and other habitat alterations.

It states:  "While these common birds are in decline, others are taking
their place or even elbowing them aside. The wild turkey, once in deep
trouble, is growing at a rate of 14 percent a year."

Actually in Ontario, where, after being extirpated, the not-so-wild 
turkey
was "re" introduced (including, of course, into places it never 
previously
was recorded) for the amusement of hunters I think it is increasing even
faster.  Both it, and the environment, would be different from what was
here, but having read some of the very early accounts of Wild Turkey
abundance well prior to the start of the 18th Century, I question if, in
fact, it is anywhere yet near primal, pre-colonial numbers in the 
eastern
U.S.

It states:" The double-crested cormorant, pushed nearly to extinction by
DDT, is growing at a rate of 8 percent a year and populations of the 
pesky
Canada goose increase by 7 percent yearly."

We now have ample evidence that the Double-crested Cormorant was once 
far
more abundant in North America than it yet is (see, for example: Wires,
Linda A., and Francesca J. Cuthbert, Historic Populations of the
Double-crested Cormorant  (Phalacrocorax auritus): Implications for
Conservation and Management in the 21st Century, Waterbirds 29(1): 9-37,
2006.) In 1891 a flock of migrating cormorants that was described as 
being
four miles long and one and a half miles wide was seen in Minnesota.  
And as
late as 1926, a flock estimated to have between 100,000 and one million
birds in it was seen migrating up the Mississippi River.

I am sure that is true for the "pesky" Canada Goose, as well, a species
whose eastern migratory population is in decline while non-migrant birds
increase (except that non-migrants may join the migrants, and vice 
versa).

It states that blue jays and crows are "doing just fine" although it 
cites
West Nile Virus as a factor in bird declines.  Corvids are main victims 
of
WNV and in my area there appeared to be a distinct decline in Blue 
Jays, at
least.

It states: "The population of the greater scaup is only one quarter of 
what
it was in 1967, the fourth biggest decline in common bird populations in
North America, according to new study by The National Audubon Society."
Scaup are also prime consumers of a major invasive species, the Zebra
Mussel.  So we have a species in decline, a species that serves human
economic interests, and we...what...protect it?  Don't be 
silly...bluebills
are delicious and fun to shoot.

Same with Northern Pintails, a species that, the article claims, has 
dropped
77 percent.  If a species is in decline, does it really produce a 
"surplus"
that can be hunted with no impact to the population?  Makes no sense to 
me.

Barry Kent MacKay
Markham, Ontario, Canada