As regards Bob Reilly's comments about banding, I would like to
respectfully submit that one might stop to consider that the work of
thousands of researchers, conservationists, and dedicated volunteers could
indeed be
detrimental to our birds. I have been to banding sites where birds are
handheld for many minutes while the bander talks about them to the visiting
"public". The birds are obviously terrified--they have no way of knowing what
is
going on--and this has to be extremely stressful to them. I would not be at
all surprised if some of these birds die after being released, just as fish
do after being handled by researchers.
Consider the fact that a migrant has evolved to add just enough fat to its
body to have the energy to carry its average weight across the Gulf of Mexico.
If the amount of a bird’s weight is increased, even by as small an amount
as that of a band, the bird may well use up all of its fat (energy) before
reaching land. Evolution has not taken into account man’s meddling.
According to the laws of physics, the more weight to be carried over the
miles, the sooner a given amount of fuel to carry it is going to be burned up.
Even if a songbird’s energy does not give out until it is as close as a few
inches from land, the end result is disastrous because the poor creature is
going to drown if it falls into the water. Songbirds do not swim.
In “Catching the Yucatan Express” (Birder’s World magazine, April 1999), it
was stated that “Biologists routinely discover thousands of dead birds that
have washed ashore. The sternums, or breast-bones, of these birds often are
as sharp as knife blades because the birds have burned their pectoralis
muscles as a last-ditch source of fuel (emphasis mine).” This statement makes
it
painfully clear that migratory birds are barely capable of successfully
migrating as it is. To expect them to carry even the tiniest bit of added
weight
caused by a band is abhorrent when you think about it.
Researchers may believe that they are not harming these birds, but no one
can deny the laws of physics. It has been reported that birds are burning
0.6
percent of their body weight per hour, and if they do not find land within
about 2½ days of nonstop flight, they will die. If tailwinds stop or change
direction, lengthening the trip by many hours, even the 0.005 grams of a
Ruby-throated Hummingbird band makes a difference in how soon the hummer’s fat
supply runs out as it tries to travel across the 600 miles of the Gulf of
Mexico.
As yet, no one has come up with a common cause for the decreasing numbers of
many different species of migrant birds. For example, some birds are
obviously disappearing due to habitat loss while other kinds of birds that
still
have plenty of good habitat are decreasing in number as well. A common factor
has so far eluded researchers.
Some researchers have asked, “Is it better to do nothing as we watch the
populations of birds decline?” But what if bird banding is actually the
common
factor in the decline of all of these migratory-bird populations? It is
easy to overlook the obvious, especially when a method of research has been in
existence for as long a time as bird banding has been.
No one seems to want to seriously consider the possible consequences of this
activity, probably because 0.005 grams is such a tiny amount to full-grown
men and women. Or perhaps researchers loathe the thought of giving up a
relatively easy way of gaining knowledge about the avian world because they do
not
know what other scientific method can effectively replace bird banding.
However, I would suggest that the effect of banding upon our migratory
species that pass over large bodies of water be taken quite seriously—for we
may
be helping to kill off the very creatures that we are trying to save.
Marlene
Author, The Nature-friendly Garden (Stackpole Books, 2006)
