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| How
fast do peregrine falcons fly? |
| In
level flight, peregrines are fast but no faster than many other
birds. Peregrines excel at diving at high speeds, usually in
pursuit of prey. The maximum peregrine dive speed has been estimated
at approximately 220 miles per hour. Typical dives range between
150 to 200 miles per hour. Although several other species of
birds may on rare occasions reach comparable speeds, the peregrine
falcon is certainly one of the fastest animals on earth.
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| What
do peregrines eat? |
| Peregrine
falcons are almost exclusively avian predators. They catch and
eat other birds, usually on the wing. Pigeons are a favorite
source of food, particularly in urban environments. However,
falcons are very opportunistic hunters and eat a wide variety
of prey. On rare occasion, small mammals are also eaten. Peregrine
falcons are renowned for their hunting ability, and it is while
hunting that they use their spectacular powers of flight to
the utmost. |
| Where
do they go in the winter? |
| Naturally
occurring populations, or subspecies, show tremendous variability
in their migratory behavior. Some subspecies do not migrate
at all. Others travel great distances. For example, the tundra
subspecies nests on the arctic tundra of North America and winters
in central South America. Probably due in part to its genetic
mixture, the reintroduced population demonstrates all of this
variability. Some birds, even those with very northern territories,
do not migrate. Others do. To date, all of the peregrines that
have established themselves in Fargo have migrated. They typically
leave in September or October and return the following March.
So far the earliest return date is March 15. With one exception,
the Fargo falcons have not been sighted in the winter, so we
do not know exactly where they go. On February 23, 2004, Frieda,
was photographed in St. Paul, Minnesota. It is not known if
she spent the winter in that area or was simply moving through. |
| How
long do they live? |
| Peregrines
have a long life span. Individual birds have been known to live
in captivity for more than twenty years. To date, the longest
a peregrine is known to have lived in the wild is nineteen years.
Of course, typical life spans are shorter, and first year mortality
rates are high. If a falcon survives its first winter, however,
the odds of continued survival improve dramatically. |
| Do
falcons mate for life? |
| Not
exactly. Like many animals, falcons are extremely territorial.
Furthermore, once they have established a territory, they will
typically return to it each year and defend it against intruders.
Because this is true of both male and female falcons, the same
birds will frequently rediscover one another every spring at
their common breeding territory. In this manner, they may continue
to mate over an extended period of time. However, pairs do not
stay together during the winter. Furthermore, should one member
of a territorial pair fail to return or be displaced; the other
bird will readily accept a replacement. |
| When
do falcons begin to breed? |
|
On
occasion, falcons begin to breed the year after they hatch.
This was particularly true when the reintroduced population
was young, and there was limited competition for breeding
territories. Most birds, however, do not begin to breed until
they are two years old, and fully mature. If they are delayed
in finding a territory or mate, it may take individual birds
even longer. For example, Dakota Ace was three when he first
laid claim to Fargo, and four when he first became a father.
He is now seven, and in his prime. Frieda, the current territorial
female, is now three. Therefore, the Fargo falcons are both
at an optimum age for breeding.
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| How
long do falcons breed? |
|
As
the reintroduced population is still maturing, it is
hard to know just how productive individual birds may
be. The current record holder is Meg, who raised a total
of 43 young. She also established a longevity record
for wild female peregrines, and was 17 years old when
she recently died. In general, territorial males seem
to hold a survival advantage over females. This may
be that conflicts among female birds are more often
fatal. In 2004, only two females 10 years old or older
were still holding territories in the Midwest. By contrast,
there were at least 12 territorial males who were at
least 10 years old, and the oldest of those was 19.
Currently, the most productive known male is 15 year
old Kato who has nested for 13 years on the Colonade
Building in Minneapolis, fathering a total of 41 young.
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| Do
falcons build a nest? |
|
The
short answer is no. Most of the manmade structures built
for peregrines contain a nest tray filled with gravel
or sand. The birds will typically "scrape"
a depression where the eggs are laid, but no other form
of nest building occurs. If natural nest sites are utilized,
the eggs are typically laid directly on the ledge or
cave utilized as a nest site. On rare occasions peregrines
may use an abandoned nest built by some other raptor
as a platform on which to lay their eggs.
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| How
many eggs do they lay? |
| Clutch
sizes vary from one to five. Three or four seems to be the norm.
Eggs are laid at intervals of two to three days. Incubation
usually does not start in earnest until the clutch is almost
complete. The female typically does most of the incubating,
and during this period is fed by the male. The incubation period
is approximately thirty-three days. The young then spend about
six weeks in the nest until they are old enough to fly, or "fledge." |
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| What
happens to the young peregrines? |
| After
fledging, the young remain dependent on their parents
for a period of time, while they improve their flight
skills and learn to hunt for themselves. Over time the
fledglings become increasingly independent and dispersed.
Within one or two months full independence is gained,
and the young break all bonds with their parents and nest
site. The ultimate dispersal process is random. Individual
birds often travel considerable distances in the search
for a territory of their own. The birds who have appeared
in Fargo in recent years are typical of this dispersal
process. The male was released in Sioux Falls, South Dakota,
and arrived in Fargo three years later. The two females
were hatched respectively in Omaha, Nebraska and Alma,
Wisconsin. Each first came to Fargo as a juvenile bird. |
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| What
has happened to Fargo's fledglings? |
| Since
2001, a total of 9 young peregrines have fledged from the nest
box on the Bank of the West building. First flights are often
problematic. At least three ended on the ground, requiring a
rescue. In 2003, one of the young birds was seriously injured
several days after leaving the nest and had to be euthanized.
Otherwise, all young are believed to have successfully gained
independence and left the area. To date only one of our young
birds has been reported after leaving Fargo. Holly fledged in
2003, and left this area that August. The following summer she
was reported nesting on the McKenzie Seed Building in Brandon,
Manitoba. |
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Information provided by Wick Corwin
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