Although scientists counted a record number
of manatees during the 2001 Statewide Synoptic Survey in Florida, there
is no question that this endangered species still needs protection for
1) Has There Really Been a Significant Increase in Manatee Population?
Save the Manatee Club scientists believe that the 2001 record high count
of 3,276 manatees (637 more than the previous high count of 2,639 in
1996) was an irregularity. They state the record high count was simply
the result of having ideal counting conditions, and is not a sign of
a rising population.
Dr. Bruce Ackerman noted that "Counts can be highly variable due
to weather conditions, and this year's [2001 record high] count isn't
entirely unexpected", because of the perfect counting weather.
Importantly, he added that even with the high count in 2001, scientists
remain cautious about the overall manatee population.
While boating groups may say the 2001 record count shows a significant
population increase, manatee scientists have strongly disagreed. In
a March 1, 2002 Palm Beach Post article, Save the Manatee Club Biologist
Patti Thompson indicated that "It is utterly irresponsible for
them (boating groups) to say that manatees are thriving. The data are
not complete enough yet to even say whether they're stable, much less
2) Do Endangered Species Need More Protection? Why?
The manatee is an endangered species, and the record high count in 2001
doesn't lessen the need to protect them. Dr. Ackerman pointed out that:
3,000 manatees is not that many individuals of an endangered
species. It might seem like a lot more than 2,600, but it's
not that much more.
[Because this is an endangered species]
It's like having your life savings being $3,000."
When the entire population of a species is so small, it is placed at serious
risk if a widespread disease comes along. Just a few years ago the manatees
faced such a risk when they were exposed to red tide. In 1996 alone, red
tide alone killed 151 manatees, and that didn't even count all the manatees
that died from other causes that year!
Already this year too, scientists from the Florida Marine Research Institute
suspect that 27 manatee carcasses brought in from four southwest counties
between March 15 and April 16 died as a result of exposure to red tide.
Samples collected during necropsy were sent for a toxicological analysis
that shows whether the red tide toxin is present in an animalís urine,
stomach, and liver.
A federally appointed advisory panel, The Working Group for Unusual Marine
Mammal Mortality Events (WGUMMME), has declared this an unusual mortality
3) How fast is the rate of reproduction in this species?
Manatees have a very slow reproduction rate. According to Nancy Sadusky
from Save The Manatee Club, scientists believe females do not become sexually
mature until five years of age. Males are mature at approximately nine
years of age. Once they are mature, manatees usually bear one calf --
twins are rare. Intervals between births range from two to five years,
and the gestation period is approximately 13 months.
very slow reproduction rate emphasizes that the death of any mature
manatee can have a significant impact on the population.
It underscores how important it is to prevent deaths and injuries
to the manatees.
4) Will the death rate likely increase or decrease? From what causes?
of manatees that die each year in Florida has generally increased over
the years. When scientists started counting in 1975, they recorded 29
manatee deaths that year, 6 of which were from boating causes. Last
year, the 2001 count was 325 manatee deaths, with 81 coming from boating
related deaths have followed right along with the increasing number
of boats in Florida.
5) Do non-fatal injuries affect Manatee reproduction?
In addition to the growing number a manatees killed by boats each year,
many more are hit by boats and survive, but often with horrific injuries.
Scientists are just beginning to study what effect these injuries may
have on the overall health of the Manatee population? One of the topics
they will study is the question of whether injured manatees may not
be reproducing successfully?
6) Are other species protected more than Manatees? Why?
Several manatee scientists have noted that manatees do not receive the
same level of protections as other species, especially when the data
shows that so many deaths are being caused by a single cause-- boating.
In a March 1, 2002 article in the Palm Beach Post, Greg Bossart, director
of marine mammal research and conservation at Harbor Branch Oceanographic
Institution, said that this level of human-caused death would not be
tolerated for other species. "'If we were doing these same things
to any dolphin species, I guarantee you there would be a public and
government outcry from here to Washington,' Bossart said. 'Animals that
have more appeal to our emotional needs or spiritual needs or whatever
get more attention. They (manatees) didn't get a TV series.'"
What if Manatees
had gotten their own TV show, like Flipper?
Out of Every Four!
In the same article, Save the Manatee Club biologist Patti Thompson
said that people should be shocked. Approximately 25% of manatee deaths,
that's one out of every four, are killed by boating, which she described
as "something that was preventable just by being more careful."
She commented that if there was a single thing causing 25% of human
deaths, "don't you think we'd be pretty worried about that?"
This! Journaling Questions
Discuss the questions below, which all play a role in understanding how
fragile the manatee population really is:
1) What is the size of the manatee population?
2) Should an "endangered" species deserve more protection?
3) What is the rate of reproduction in manatees?
4) Do you think the death rate will likely increase or decrease? From
what causes? Can deaths be reduced?
5) Can non-fatal injuries affect manatee reproduction?
6) Are other species protected more than manatees? Why?
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