The Red-tailed Hawk reported by J. Lemons yesterday near Emerald Downs is
part of a study we have been conducting at Seattle-Tacoma International
Airport since June 2001.

The goal of this long-term project (developed jointly by Steve Osmek, Port
of Seattle biologist, and Bud Anderson, Director of the Falcon Research
Group) is to reduce the number of potential bird strikes involving raptors
and increase aviation safety for the general public at large.

Maybe this is a good time to present some more details about the program.

It turns out that Red-tailed Hawks are one of the raptor species most
commonly involved in bird strikes at airports across the nation.

One of the categories most often involved in these strikes is recently
fledged juvenile Red-tails raised at nests on or adjacent to air fields.
Such birds, after leaving the nest, often move onto the runway areas to
either forage or to gain lift from the thermals generated by the sun-warmed
concrete. Since they are completely inexperienced about large aircraft, they
simply do not recognize the danger and are subsequently struck, often with
catastrophic results for both the bird and the aircraft.

As a longtime raptor biologist, one of my goals on this project was to try
to reduce or eliminate this problem in the best way possible for the hawks
and the Port of Seattle.

We are advocating a new and different approach at Sea-Tac and I have to
honestly say the Port has been really progressive in their support as well
as being great to work with. Personally, I think they deserve a lot of
recognition and credit for all this.

Anyway, Steve Osmek and I have been developing some new and innovative
techniques that we think are working really well.

For starters, we locate, identify, capture and wing-tag (with numbered
yellow tags) all of the five pairs of adults nesting around the airport
perimeter. In this manner, we know which hawk is which and can follow their
history over the years.

Remarkably, several of these resident adults have remained at Sea-Tac for
many years, including two individuals for at least 9 years and counting.
This is pretty remarkable stuff to me, especially since one of these birds
has nested essentially UNDER the north approach lights for nine years.
This clearly demonstrates that adults can become habituated to jet aircraft
movements.

Why is this important?

Well, Sea-Tac generally has about 700 aircraft "movements" (take-offs and
landings) per day. If you multiply that by 365 days per year (255,500
movements) and then 9 years (2,295,000 movements), you can see that adults
can learn to avoid jets and, in my opinion, do not have to be removed from
our airport. Avoiding over 2 million aircraft movements is a pretty
convincing dataset.

I should say that, although this is the case at Sea-Tac, it may not be true
for other airports.

So we now consider the adults to be our allies at the airport. They are
often (certainly not always) observed chasing other "intruding" and less
experienced hawks from the area. We appreciate that too.

So much for the adults. But what do you do about those naive juveniles
fledging up onto the runways every summer?

Since 2002, we have been tracking each nest at the airport and monitoring
the Red-tail breeding cycle. When a pair does raise young, we have a
professional climber go into the nest and bring down the nestlings at four
weeks of age for their own safety.

I take these nestlings 75 miles north to the Samish Flats where we
raise them to independence during the summer months in a safe and ideal
habitat. Being raised here in Skagit County, they imprint on this area and
remain without returning to the dangers at the airport, a win for them and a
win for the airport. In fact, none of these raised young have returned to
Sea-Tac that we know of, at least up to now.
And this brings us to the bird observed by J Lemons yesterday.

Although we can monitor the nests on and adjacent to the airport, we can't
keep track of all of the nests in the surrounding area. And it amazes me how
many there are in such a "developed" area as the town like Sea-Tac and its
environs.

And since the airport is so magnetic to raptors (food/lift), we get a lot of
young hawks heading over our way once they learn to fly on their own.
I suspect that they initially find the airfield from their early soaring
flights. Seattle-Tacoma International Airport is very obvious from the air.
Check it out on Google Earth.

So, when we see juvenile birds arrive, our goal is to get them away from the
runways as soon as possible. Part of my job is to catch them and transport
them 75 miles north to a better and safer "restaurant", in this case, the
Samish Flats.

Starting last year, we decided that we needed to learn more about what
happens to these relocated young birds. So we started to put on light blue
wing-tags to differentiate them from the yellow-marked adults.

Thus far, we have applied 26 numbered blue tags to juveniles (12 in 2009 and
14 so far in 2010) and we are starting to learn some really interesting
stuff.

For example, some of these re-located young will remain here in Skagit
County. Becky Rosencrans is watching one (blue left 7) in Mt. Vernon these
days ( captured at Sea-Tac on 20 January 2010). Others have gone north (one
was seen in Bellingham last year and two more along the I-5 corridor).

Most recently, we are finding that if a young bird has been raised (i.e.
imprinted geographically) around Sea-Tac (one of these pre-migrant August
birds), they can return the 75 miles back to Seas-Tac inside a week. We have
seen that twice now.

But with these returning birds, we generally just see them a single time and
not again. While they might return, they may not necessarily stay put at the
airport.

So J Lemons' hawk (and BTW, good call, it was a male) was captured at
Sea-Tac on 24 August 2010 and driven north to the Samish Flats where it was
tagged and released that same day.

We consider all of these August birds as Sea-Tac "locals" and would expect
them to return. However, this bird was seen all the way down by Auburn.
While I am speculating here, it would seem that it might have been raised
down there and perhaps dropped in at Sea-Tac for awhile after an extended
exploratory soaring event. Who knows?

But an important point here is that just because an immature returns to an
airport, it doesn't necessarily mean that it will remain there.

I hope that this message will help everyone to understand the purpose of
these tags and what we are trying to accomplish.

And I really want to thank J Lemon, whoever you might be, for taking the
time to report this sighting. It is important in many ways. Glad to see that
the bird is doing well.

Any other sightings of wing-tagged Red-tails in the future would also be
much appreciated (see new e-mail address below).

Finally, please let me thank Steve Osmek, Jack Bettesworth, Sue Hindman and
Mark Gleason for helping with this project and relocating nearly 300
hawks over the years.

Thanks,

Bud Anderson
falconresearch at gmail.com
(306) 757-1911
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