DIVE SLATE
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FALL 2012
G
ee whiskers!” Little Orphan Annie used to exclaim.
Her once-common catchphrase could apply anew
to some extraordinary things we are learning
about the whiskered Florida manatee. Manatee
mothers and their calves form a strong bond that lasts for two
years or more. During this time the little ones learn what they
need to know to survive, including what to eat, where to go and
how to stay warm, as well as manatee social skills.
What happens when a little manatee calf is orphaned? It
turns out that a mother manatee, even one with her own
calf, will sometimes adopt an orphan in need. This adoption
behavior has been witnessed at Three Sisters Springs, part of
the Crystal River National Wildlife Refuge in Florida.
“
From genetic studies using an exclusion process based on
inherited markers, we have observed adoption of unrelated
calf manatees by lactating mothers,” said manatee expert Bob
Bonde, wildlife biologist with the U.S. Geological Survey’s
Sirenia Project. “Although not common, this has been
observed in a few cases during long-term studies conducted
in Crystal River, Fla.”
Last winter back in the springs, we noticed a very skinny
female calf without a mother, vocalizing repeatedly with loud
squeaks. She must have been orphaned quite young; she
would approach any manatee, regardless of age or gender,
squeaking loudly and attempting to nurse under any available
flipper. We notified the proper authorities.
Later we observed this little orphan nursing from one
particular adult female over subsequent weeks. From our
photographs, the team at the Sirenia Project identified the
potential adoptive mother. Cathy Beck, wildlife biologist, said
this adoptive mother is CR554, a female rst documented
in March 1999. “Since that rst sighting, she has been seen
with four calves in addition to this young adoptee,” Beck said.
“
CR554 has several subtle but unique features that we use to
identify her, including two small tail notches and a white scar
on her tail — visible despite the algae coating her skin.”
It was touch and go for a while as the skinny orphan hadn’t
ever learned to stay with one mother, but the mother manatee
Little Orphan Manatee
If not for a mother manatee’s willingness to nurse her
this winter, this orphaned calf in Three Sisters Springs,
Fla., may not have survived her first year.
CAROL GRANT