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Few scientists know about condors, but many are aware
that these giant birds of incomparable majesty have
dwindled to less than 35 in the 1970s. In an effort to
solve the mystery and save this species, scientists
gathered for a brainstorming session. Abe and a few
others proposed fitting some condors with radio
transmitters to tack them and learn about their nesting
and feeding habits. With radio telemetry, they could
also locate dead birds and discover the cause of their
death. Other condors would be trapped for breeding in
captivity. To produce a captive stock rapidly, Abe
suggested taking eggs from nests to hatch in incubators.
he knows that most bird species will 'double-clutch' and
lay a second egg in the same breeding season if the
first is lost. He thinks that condors are no exception.
As expected, Abe's proposals sparked off a howl of
protest from a group of equally concerned conservation
groups. They claimed that a bird raised in captivity
would never adjust in the wild. One even proclaimed that
the condor 'is not an electric toy to play with,
blindfold, manhandle, peer into, wire for sound, or put
behind bars'. After months of bureaucratic infighting,
Abe was finally granted a permit to carry out his
program. With a few members of the rescue condor team,
Abe set out the task of tracking the bird. Before long,
they spotted two condors at a nesting cave. Watching
through a telescope, they were enthralled to see one of
the birds lay a pale blue egg. 54 days later, a member
saw a beak cutting through the shell. On the morning of
the 56th day, there was a newborn chick. With the
parents away foraging, Abe decided to weigh and measure
the nestling.
The scientists continued to observe the bids from
afar. By photographing each bird in flight, they
developed method of individual identification that
led to an accurate census. They managed to have two
condors flying with a radio transmitter and a numbered
tag on each wing. The captive-breeding program was also
fully launched in the early 1980s as the scientists
began pulling eggs from nests. All were successfully
hatched at the San Diego Zoo. The breeding pairs in the
wild promptly laid second, even third, eggs proving Abe
right about double-clutching. One day, a transmitter
signal alerted scientists that a condor in the High
Sierra was not moving. The bird's frost-covered body was
found. A post-mortem revealed a silver of a lead bullet
in the bird's gut plus toxic levels of the metal in its
blood. The condor had probably ingested the bullet
fragment while feeding on a hunter-killed deer.
In captivity, the wild birds bred easily. Their
keepers worked behind one-way mirrors and used hand
puppets, shaped and textured like an adult condor's head
and neck, for feeding and preening. This was done so
that the chicks would not catch a glimpse of people and
could not imprint to them. When a total of 13 chicks
hatched in 1990, the scientists were convinced that the
captive condor flock would continue to increase rapidly.
They were also encouraged by the arrival on the market
of all-copper bullets that had superior ballastics to
lead bullets. If hunters chose them and if copper proved
less toxic to condors, the bullets might be a major step
in saving the majestic birds. In late 1991, four young
condors were flown by helicopter to a high ridge in a
sanctuary. They were freed into a spacious roost box,
stuccoed to simulate a cave. Outside the door was a
nylon-netted feeding ledge from which the four could
gaze out over the mountains and fell the wind in their
feathers. They remained in the pen for two months to
become acclimatised. On the day the scientists were
waiting for, a cloudless morning, the door from the
roost to the ledge was opened. During the night, the
nylon mesh had been taken away, and now nothing stood
between the birds and freedom. One after the other,
heads bobbing in curiosity, the birds spread their
glossy wings and hopped into the air. Clumsily plopping
back to the ledge, they flapped and hopped until, one by
one, they managed a brief wobbly flight. A month
later, the four condors were spotted near the cliffs,
soaring and gliding in the thermals. By December 1992,
eight condors had been freed. More birds would be freed
in the coming years. The scientists knew that they were
right on schedule and that the California condor would
be back. |
