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What's So Special About This
Bird Anyway?

Physical Characteristics
Peregrine Falcons
are medium sized raptors with a wingspan of 3 -
4 feet and a weight of about 2 pounds. Their backs are slate
blue-gray; the undersides are pale under the wing with a barred
chest. They have black helmeted heads or black sideburns. There is
little difference in coloration between the male and female of the
species though there can be variations among individual birds.
Immature Peregrines
are generally brown with heavily barred
undersides.

The peregrine's hooked beak has a notch, which in falconry terms
refers to a falcon's tooth that is used for severing the
spinal cord of prey. The female is generally referred to as the
falcon and is 1/3 bigger than the male, who is referred to as
the tiercel. Peregrines
were once called duck hawks in the
United States. They have a distinctive cak cak cak sound when
agitated and can be heard vocalizing with an e-chup e-chup e-chup
to each other. In a dive they are the fastest bird in the world,
clocked by skydivers in excess of 200 mph. In level flight, the
peregrine moves along at about 80 miles per hour.
There is normally only one pair of Peregrines
living on Morro
Rock at any given time. They are very possessive of their territory
and will fiercely drive off intruders. Any hawks, eagles, or
vultures that wander by can expect to be harshly evicted from the
area. Having said that, the breeding season of 2001 was a surprise;
a second pair of Peregrines
nested and raised 3 young.
Hunting
The peregrine is an efficient predator, feeding almost
exclusively on birds and, in some instances, bats. They hunt in the
air, flying over small to medium-sized prey. When a bird has been
selected, the peregrine dives with dazzling speed, hitting with an
impact that often knocks the bird unconscious or kills it
immediately. This dive, referred to as a stoop, has been
clocked at over 200 miles per hour.
The prey item is scooped up with the peregrine's sharp talons. If
the bird is still alive, the peregrine quickly kills it with a bite
to the neck. The peregrine carries its catch to a ledge or
sometimes, especially if the bird it has killed is heavy, will let
it drop to the ground and eat it there. It removes the bird's
feathers and tears the flesh with its strong beak. Small prey is
sometimes eaten on the wing.
Morro Bay provides a wide variety of habitats for Peregrines
to
hunt in, including beaches, dunes, mudflats, salt marshes, hills,
valleys, and Morro Rock itself. Peregrines
in urban areas may have a
diet composed chiefly of pigeons, but the Morro Rock Peregrines
have
a veritable buffet to choose from.
Raising A Family
Peregrines
generally mate for life, but a new mate is readily
accepted if one dies. The tiercel will show off for the falcon with
intricate aerial displays. He also brings her food offerings.
Breeding activity on the central coast of California generally
begins early to mid-February. However, mated pairs will sometimes
copulate throughout the year. These matings are ineffectual; she
won't ovulating and he won't be producing semen until early spring.
It isn't uncommon for copulation to begin right around the time of
winter solstice and this may be a part of courtship to help get the
hormones going.
Peregrines
nest on cliffs and ledges hundreds of feet high. Here
at Morro Rock the Peregrines
often choose to nest on the south or
southwest side of the Rock. (Urban Peregrines
nest on the ledges of
tall office buildings and in the towers of bridges.) These nests,
called "aerie
s," do not contain what we tend to think of as nesting
materials. Rather they are "scrapes." The female selects a site then
scrapes out an indentation in which to lay her eggs. The falcon will
lay up to four eggs. Incubation lasts about 33 days.

During mating and nesting season the tiercel does the hunting,
bringing food back to the falcon and the young. Often the food will
be passed to the falcon in an aerial food exchange. The tiercel
flies in, calling to the falcon. She joins him in the air, flying
beneath him. He passes the prey item as she rolls over to take it in
her talons. It is a beautiful display of teamwork and aerial
acrobatics.
Both Peregrines
incubate the eggs, though the female does most of
the sitting. The tiercel seems to relish his chance to care for the
eggs and sometimes seems to have to be chased off when she is ready
to return to the nest.
Baby Peregrines
are called "eyasses" and are fierce looking
little puffs of white down. They grow quickly and can be seen
teetering near the edge of the aerie
long before they are ready to
fly. They fledge (take to the air) 40 - 45 days after hatching. It
is a bit disconcerting to watch as they flap their wings and take
that first step away from home. Equally interesting to watch are the
first attempts to land. At times the intense grace that is
characteristic of the peregrine is evident from the beginning. Other
times they are as awkward as big puppies.
With instruction from their parents and a lot of practice,
immature Peregrines
begin to hunt at about 9 weeks. This is a great
time to observe Peregrines
at Morro Rock. The young are active and
very vocal, so are easy to spot. They will maintain their immature
plumage for the first year, molting into adult plumage in the
spring. They become sexually mature at 3 years of age.
Unfortunately, generally only 50% of all Peregrine Falcons
fail to survive their
first year. Of those that do survive, the average lifespan is 13-17
years.
We Almost Lost Them
By 1965 the American Peregrine Falcon
was completely absent in
the Eastern United States. In 1972 there were only two pairs known
in California, one of which was at Morro Rock. The Peregrine Falcon
was declared to be an endangered species by the U.S. Fish and
Wildlife Service in 1973.
Steve Schubert, former Morro Coast Audubon president, has
compiled a history of the peregrine recovery efforts in his
fascinating report, The Peregrine Falcons
of Morro Rock - A
History. Email him at
Steve Schubert to purchase a copy.
Delisted in 1998, the Peregrine Falcon
will continue to be
observed for a minimum of five years. If, during this period, it
becomes evident that the peregrine needs the protection of the
Endangered Species Act, it will be relisted. The peregrine is still
protected under the Migratory Bird Treaty Act, which prohibits the
taking, killing, possession, transportation, and importation of
migratory birds, their eggs, parts, and nests except when
specifically authorized by the Interior Department, such as in the
case of regulated hunting seasons for game birds. The California
Endangered Species Act also still protects Peregrine Falcons.
DDT, a pesticide used widely throughout the world since its
invention in the 1940's, caused the thinning of the eggshells of
Peregrines
and other birds. These weakened shells can be broken by
the adults while being incubated or may dry out quickly, causing the
egg to die. Use of DDT was restricted in the United States in 1972,
but residue remains in the environment. DDT is still used in Latin
America. Birds who feed there and then migrate into the United
States bring this poison to the Peregrines.
Other threats to the peregrine population include the use of
myriad contaminants and loss of habitat.
So, what's so great about these birds? Their beauty, fierceness,
dazzling speed, grace, and superior flight can thrill a heart and
take your breath away. Your spirit soars with them. They are
independent and proud, loyal to their mates and young, intelligent
and spirited. We who live in Morro Bay share this space with a pair
of Peregrine Falcons
and are fortunate to be able to make them a
part of our lives. It is not an exaggeration to say that people come
from all over to world for the opportunity to catch a glimpse of our
Peregrines. The Peregrine Falcons
are part of what makes Morro Bay
such a wonderful place to live and visit.
Not good enough? Why bother to save them? From a purely selfish
human standpoint, Peregrines
are a barometer of what is wrong with
our own environment. Peregrine Falcons
are at the top of the food
chain. The chemicals we created and spread into the environment
almost took them to extinction as it got into their food. Like
canaries in coal mines, Peregrines
let us know when our environment
is polluted and our own survival threatened.
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"I passed through Morro Bay a couple times
in the early 70's, looking to see a peregrine, but missed
the birds each time! This was in the bad old days, when
there were only two known breeding pairs in the state. I
remember security was high- there was electronic
surveillance of some kind, and the ranger on duty at the
rock was quite secretive about the actual nest site. This
was about the time it had been raided by poachers.
"I finally saw my first peregrine in
1979 in the San Jacinto Wildlife Refuge (Mystic Lake), near
my home in Riverside. It was late July and a tropical storm
had blown all kinds of stuff up from Baja. My friend Pete
Clark had spotted a magnificent frigate bird soaring over
UCR, and Mike Patten and I went to Mystic Lake on the chance
it would be there. As we were walking across the fields
toward the lake shore, the sun was setting in our faces- 100
degrees, and thunder-stormy. A flock of curlews flushed in a
panic off to our right, and we saw the peregrine pulling up
out of a dive. It swung through the curlews, then banked
off, making a half-hearted swipe at a marsh hawk as it
passed, then flew out to the east. Mike had seen a few
before and wasn't too excited (he yelled at me to get a
grip), but I watched the bird till it was out of sight.
Wonderful bird, and my first sighting was just as I would
have wished- beautiful setting, and the peregrine behaving
as I'd always read they did- wild, fast, and imperious."
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