Januar 2017 airberlin magazin - Hallo Kuh!

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Im Uhrzeigersinn von oben links:
Schnorchler und Kanus im Crystal
River; Seekuh taucht zum Atmen
auf; Dunst über der warmen Three
Sisters Spring; Virginia Edmonds
Clockwise from top left:
Snorkellers and canoes on the
Crystal River; a manatee surfacing
for a breath; mist above the warm
spring; zoo keeper Virginia Edmonds
ground for the past 36 years. He was a park ranger
at Blue Spring for three decades, and now works
for the animal conservation organisation Save the
Manatee Club. It is 8.30am, and the air
temperature is around 27˚C – a typical subtropical
winter’s day is beginning. It’s time for
Hartley’s morning roll call with the manatees, as
the Caribbean round-tailed sea cows are more
commonly known. Every morning, Hartley sets
off for the spring run by boat and takes detailed
notes on all of the manatees he finds there.
His morning routine begins by measuring the
river’s temperature. “Twenty-two degrees is the
magic number,” explains Hartley. “That’s when
the manatees start coming into the springs.” In
fact, today’s temperature is just below 22˚C – for
the first time this autumn. Two park rangers are
balancing carefully on their canoe as they attach a
new sign to the spring’s entrance, which says, “No
kayaking between 11:00 and 17:00.” Disturbance
must be kept to a minimum when the manatees
come to the spring.
Manatees are an endangered animal. They
have no predators, but the aquatic mammals face
three main dangers: cold stress, algae blooms and,
as is often the case, humans. A water temperature
above 20˚C is vital for the animals’ survival. If
they are forced to remain in colder water for long
periods, they die. In 2010, 282 Florida manatees
fell victim to cold stress, according to Dr Bob
Bonde, a manatee expert at the US Geological
Survey research institute. In very cold winters
they sometimes don’t manage to find warm water
quickly enough. “At the same time they’re actually
very resilient. Their T cells, responsible for
immune defence, are incredible,” he says.
Algae blooms in the Gulf of Mexico off the
Florida west coast affect the manatees’ nervous
systems and paralyse them, so they can no
longer surface to breathe. If the water contains a
particularly high quantity of algae, the manatees
may drown.
“The biggest danger to manatees is humans,”
says Bonde. Collisions with motorboats are
particularly perilous for these mammals,
which need to come up to the water’s surface >