Orcas: Killer
Beauties
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Birth and Care of the
Calf
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Orca births
in Captivity.
On September
26th of 1985, at Sea World of Florida, the birth of a baby female Orca called
Shamu, was the first Orca to be born and bred in a zoological environment; in
other words, the first Orca born in captivity.
On February 2
of 1,996 Sea World of Texas, was present at the second-generation male Orca
birth. That male Orca is the descendant of the first Orca born in captivity:
Shamu.
Many other
young has been born in the parks of Sea World, in Florida, San Diego and
Texas. The Reproduction Program in captivity of Sea World, has shown to be one
of most successful programs in the world. This program has allowed scientists
to learn many things about the Orca reproduction, how fast they grow,
how they develop, and how they learn the basics for an aquatic oriented
life.
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This is
Shamu, the first Orca born in captivity.
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Gestation,
Birth Season and Birth Frequency
The gestation
period of the Orcas lasts approximately 16 to 17 months. Calves born every
month. Based on limited data, obtained of several communities at the ocean;
Females can deliver 4 to 6 surviving calves every five years into a 25 year
period.
Head or Tail
first ?
The young is
born in the water. The young delivery happens in two ways: By the head or by
the tail. The umbilical cord is broken during the birth or after the birth.
The mother then helps it's young to swim to surface, so it can take its first
breath.
The calf at
birth.
The young
measures about 8 feet when being born (2,4 meters) of length and weight around
300 to 400 pounds. (131 to 181 kilograms). The light areas of some Orca young
can be of a creamy white color to yellow lemon more than white. This color
commonly becomes white at the age of one year. In the first days after the
birth, the tail the dorsal fin and the tail flukes gradually become
hard.
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Killer
whale calves are often delivered in both ways. by tail or
head.
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Nursing.
The calves
nurse at the nipples hidden in abdominal mammary openings, found at each side
of the female's genital opening. In Oceanariums like Sea World, there has been
observed, that the calf begins to lactate several hours after the birth and
they can lactate for over twelve months; sucking approximately 5 to 10 seconds
at a time, several times in one hour, 24 hours a day.
Calves usually
lactates near the water surface. The mother slides in a horizontal position,
with her tail arched and the young swims near her side, with its mouth in some
of the two mammary glands; left or right.
The milk of the
mother is very rich, this way the young forms an almost addictive habit, that
way the calf develop a heavy insulating layer of blubber. The fat content of
the milk in the mother increases as the young grows, oscillating between 28%
to 48% .
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A mother
Killer Whale and her calf. Photo Credit: © 1999 Amos Nachoum.
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Swimming.
An Orca mother
tends to remain near its young and directs its movements in a very safe way.
The young tends to swim near its mother and can be carried on her mother's
"SLIP STREAM" a kind of hydrodynamic wake that produces the mother when
impelling itself. This aids to the young to swim with less energy and allows
the mother and to the young to stay along with the rest of the
group
Maternal
Behavior.
While most of
the maternal behavior is probably instinctive, the inexperienced mothers do
not have much experience at the time of caring their young. In some
Oceanariums, it has been observed that the experience level of some first-time
mothers can be increased in training sessions, which shows them how to respond
at the time of caring a real young.
Calf
Development.
The superior
teeth of an Orca, appears at the three to four months after birth. The
inferior teeth appears between three to five months. The young starts to eat
fish between the three to four months. They eat consistent solid food at four
to five months.
When they reach
their first year, the young eats 50 to 60 pounds (23 to 27 kilograms) of
herrings, smelt and squid every day. The young grow between 2,6 feet (80
centimeters) during its first year, and 2,2 feet (67 centimeters) during its
second year.
Vocalization.
In studies,
made at the Hubbs-SeaWorld World Research Institute, the scientists have
determined the following things:
The young can
begin to vocalize within the first days after the birth, but the sound
production heals forms with the age. The vocal behavior is not predetermined.
The young learn during the course of their development, what calls must make
under what circumstances.
In very
probable that the young begins to develop calls like those of its near
relatives. (Commonly the mother). Those stereotyped calls are developed
between the five months and a year of age.
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