Journey North Manatee Spring 2004

Manatee Migration Update: March 3, 2004

Today's Report Includes:

Ranger Wayne's Invitation-Take the Blue Spring Challenge!
It's Your Turn: You Make the Call! CQ #9
Latest Map and Satellite Data
Aerial Manatee Count Notes from Holly Edwards: CQ#10
Meet and Learn More About Holly
What Do the Manatee Counts Really Mean? CQ# 11
Ask the Expert Now Open!

Ranger Wayne's Invitation-Take the Blue Spring Challenge!

Can you tell me who's in the Run today?

Hi Students!
I've just been in the canoe conducting my daily Roll Call, and I took a few photos of some of the manatees I saw in the Run. I'm hoping that you'll assist me in the Roll Call today! Identifying and counting the manatees each day is important so that we have accurate data and records of who was visiting, their condition and when they were here.

Although it might seem that each one of these animals looks alike, they each have distinct differences. In addition to differing sizes, shapes, and skin color/condition, etc., when you get up close there are other unique physical features that distinguish individual manatees.

Do you know what to look for?
Do you know what a skeg mark is?
What do power boats have to do with manatee identification?

Get the basics on what to look for here:

Link to Who Are You, Anyway?

Mystery Photo revealed: Tail damaged from prop
Credit: FWC

Then come on back and try to identify the manatees below:

It's Your Turn: You Make the Call! (Roll Call That Is)
Now that you've been briefed by Ranger Wayne on the basics, it's time to test your manatee identification skills for real. But wait! Before you paddle up the Run, just like Ranger Wayne, you'll need a few Essential Supplies and a few simple instructions (oh, and your life jacket too, of course).

Essential Supplies (Print and Go!)

Then, come back and answer:

Challenge Question #9:
"Who do you see in the Run today? Can you identify each Manatee in the photos?

Manatee A is ___________
Manatee B is ___________
Manatee C is ___________
Manatee D is ___________
Manatee E is ___________
Manatee F is ___________

A	B	C
D (Two views)	E	F

(To respond to this question, please follow the instructions below.)

Latest Map and Satellite Data

Latest All Manatees Migration Map
(As of March 3, 2004)
Click on Map to Enlarge

Take a look at the latest manatee maps and data.
Do you notice anything new about Giffer and Actual's latest migration locations? Where have they started traveling, and why do you think they are going there?

Link to Latest Data and Maps:
(Courtesy of U.S. Geological Survey's Sirenia Project)

Aerial Manatee Count Notes from Dr. Holly Edwards

Hi Students!
I'm Holly Edwards and I've been involved in marine mammal research for about seven years, including several aerial manatee counts. Every year, we wait for the right weather so we can climb into airplanes to count manatees across Florida. These counts are called "synoptic surveys" (meaning a general view of the whole), and are important as one of many tools biologists use to assess the endangered manatee population.

Link to Meet Holly

This year, we counted a preliminary total of 2,568 manatees during the aerial survey conducted on February 20, 2004. In comparison, the two highest counts were 3,113 manatees in 2003 and 3,276 in 2001. Weather conditions for the count this year were not as good as in 2001 and 2003. These maps show the Florida surface water temperatures during the 2001, 2003 and 2004 surveys. Compare the maps


2001	2003	2004
Click on Maps to enlarge Credit: Johns Hopkins Applied Physics Lab

and see if you can answer:

Challenge Question #10:
"How do the weather conditions in the highest count years of 2001 and 2003 compare to 2004 a lower count year? Explain how you think the different weather conditions affected the counts each year?"

(To respond to this question, please follow the instructions below.)

Good luck and I'll have more news soon.
Holly Edwards

What do the Manatee Counts Really Mean?
Many different factors including weather conditions can severely affect the number of manatees counted. For example, in 1999 and 2003, when scientists were able to do three counts each year:

Did You Know?
* there was a difference of 480 manatees between the high and low counts in 1999
* there was a difference of 252 manatees between the high and low counts in 2003

So, it is well known that the annual survey is not a complete measure of manatee population. Nevertheless, every year after the survey, there is usually some controversy about what does the data really mean. The very same count numbers will get used by different people to make very different arguments.

In "Be Careful with Numbers", we've summarized what two different groups say recent count numbers mean. Take a look, then come back and see if you can answer the Challenge Question that follows:

Be Careful with Numbers

Challenge Question #11:
"What conclusions can you draw about the size of the Florida manatee population from the fact that this year's count is lower than last year's high count? What if this year's count had been higher than last year?"

(To respond to this question, please follow the instructions below.)

Ask the Expert Now Open
Don't forget that manatee expert Nancy Sadusky from Save the Manatee Club is standing by, ready to answer your manatee questions. Be sure to send them in by the deadline of March 12, 2004 by noon central time.

How to Respond to Today's Challenge Questions:

IMPORTANT: Answer only ONE question in each e-mail message.

1. Address an e-mail message to: jn-challenge-manatee@learner.org

2. In the Subject Line of your message write: Challenge Question #9, (OR #10 OR #11)

3. In the body of EACH message, give your answer to ONE of the questions above.

The Next Manatee Migration Update Will Be Posted on March 10, 2004.