Manatee Migration Update: April 2, 2003
Field Notes from Cathy Beck
Hi Students: Some of the data points this week are not from Satellite readings, but instead come from Susan's actual visual sightings in the field (called "visuals" for short). Susan was working very hard to try to get the "visuals" on the manatees--do you know why? Link to Latest Data and Maps:
The Perfect Storm: Tracking in Rough Water Susan was still out on the water as of late Friday afternoon 3/28, when I sent these field notes. She had been calling in her updates by radio, as she was motoring around in a boat trying to visually locate each of the manatees. The day before, Thursday 3/27, we had a huge, severe storm here--it extended the length of the state. Susan was out in the rough water, in 4-6 ft. waves, until she finally had to get in for shelter. Before she came in, she did get a visual sighting on Gulliver in the channel East of Panther Key, where there was some protection from the storm. Take a look at the weather loop movie of this powerful storm, and see if you can answer:
Next, read Susan's first-hand account of what it was like in the boat. Then imagine what it must be like for a manatee during the storm, and see if you can answer the Challenge Question below:
(To respond to this question, please follow the instructions below). The Quest for Visuals
If you were tracking manatees in the field with Susan Butler, why would you be trying to locate the tracked manatees to get a "visual", and how would you do it? Read through "Satellite Tracking and Manatees", and then see if you can answer the Challenge Questions below:
(To respond to these questions, please follow the instructions below). Thumper Loses His Tag We'll keep our eyes open for Thumper, and I'll be back with more news soon. Bye for now. Cathy A. Beck, Wildlife Biologist A Lone Ranger at Blue Spring
We may still receive a few more comments and details from Ranger Wayne
this season, but in the meantime he sent in "one more comment"
late last Friday that is good news and very interesting too. Ranger wrote
that:
(To respond to this question, please follow the instructions
below). Manatee Math Challenge: Mortality Statistics for 2002 Compared to Ranger Wayne's note about boat strikes at Blue Spring, how do you think boat strikes impact the Florida manatee population as a whole? In January 2003, the Florida Marine Research Institute published its Manatee Mortality Totals for 2002. The causes and number of deaths are summarized below. After you've read
through this summary information, see if you can answer the Challenge
Question below:
(To respond to this question, please follow the instructions below). For more on FMRI 2002 Manatee Mortality information go to: Amazing Manatee Adaptations
Breathing/Respiration Take a look at the movie of a Manatee breathing. She rises to the water surface, and in only a few seconds, she exhales, and then inhales just once (we wouldn't recommend that you try this yourself!).
What adaptations help make Manatees such exceptional breathers? You'll find out in the Adaptations lesson below. As you read the lesson, think about their powerful, unique lungs. Then catch your own breath and try to answer the Challenge Question below:
(To respond to this question, please follow the instructions
below). What's Attracting Manatees to POI? Discussion of CQ #17 In the last update, Cathy Beck and Susan Butler reported that several of the manatees had been returning to POI and other inland rivers. With the warm water and food-rich sea grass beds offshore, we asked you who was swimming back inland, and why they would want to come back inland? The maps and data showed that Anna, Gulliver and Santina had all come in recently. Anna returned to POI on 3/7 and 3/11; Gulliver came up river on 3/14; Santina came up the Faka Union Canal on 3/11. (And today's data shows several recent inland trips too.) But why did they come back up? The answer lies in the manatee's need for freshwater. Like you, manatees are mammals and they need fresh water, and periodic returns inland bring them to freshwater sources. Cathy Beck explained that "While they are in saltwater, Manatees will deliberately seek out fresh water to drink--from storm drains, marina hoses, and they have also been seen mouth open, skimming the water surface during a rain storm (since the fresh water will float on the salt water). Try This! To learn more about the relations between saltwater and freshwater, try these experiments: Can You ID This Moving Manatee? Discussion of CQ #18 Did you figure out who the moving manatee was? Congratulations to Daniella and Stephanie at Iselin Middle School, who correctly identified the moving manatee as "Juan"! But how did you identify the manatee? Take a look at Ranger Wayne's comments, diagram and pictures--did you look at the same identifying features? As you'll read, sometimes it's not so easy, even for a veteran expert like Ranger Wayne!
What's Your Aerial Count? Discussion of CQ #19 Were you able to find as many manatees as Airborne Ackerman in the aerial photo from Manatee Park? (Was it harder than you expected?)
Yes, Amanda, it looks like you are very close, and that's really something
when you're looking at images like these from the air.. Dr. Ackerman reported
that "I zoomed the picture up, and printed it out in color, and I
counted 72 manatees (including three outside the main group--1 is in lower
left at edge of frame, 2 are in lower right near a power pole.) Some of
them are faint and hard to see even in the blow-up, so--that's my story
and I'm sticking to it!" Exodus at Blue Spring: Discussion of CQ #20 What conditions lead to the reduced number of manatees in the Blue Spring Run? The same conditions that bring the manatees into the Run, except in reverse. That is, the water temperature of the River compared to water temperature of the Run directly affects how many manatees are in the run. It works like this: as the temperature of the River increases above 68F, more manatees will leave the run as the temperature rises because there is no more cold water threat outside of the run. Understanding this, everyone was able to make a sound estimate of how
to fill in the River water temperature on the Blue Spring data chart.
The more manatees in the run, the lower the river temperature, and conversely,
the fewer manatees in the run, the higher the river temperature. And on
days when the manatee count was identical, one can look at the other temperature
readings to guide you. Here's how the river water temperatures match up
with the data chart:
What Drives the Dark Water? Discussion of CQ #21 In the last Update we asked "Why do you think the dark river water comes farther up the Run on some days than others? And do you see any kind of relationship between the location of the dark water and the location of the manatees in the Run?" Ranger Wayne explained that the dark river water comes farther up the Run when the river water is coldest. "The colder it gets, the heavier it is, and the further it comes up into the Run. The dark water comes in along the bottom of the Run, displacing the Run water which is warmer and lighter in weight."
You can see this on Ranger Wayne's sketches of the River water on his Attendance sheets. The river water comes the farthest into the Run on the days when the river water is the coldest. On his sheets, you can also see how the manatees position themselves in relation to the dark water. Because of its colder temperature, the manatees will generally be found up further in the Run, located "above" (on the warm side of) the cold dark water.
Binomial Nomenclature: Discussion of CQ #22
So who was it that developed binomial nomenclature? Kyle and Steven from Mrs. Bonner's 4th Grade class at Highview school in Nanuet, NY reported that: "According to our research, binomial nomenclature dates back to Bauhin, but was made popular by Carolus Linnaeus." Gaspar Bauhin was a Swiss botanist who developed an early classification system in early 1600's, which foreshadowed or anticipated the binomial classification by Linnaeus. In the 1700's, Linnaeus developed improvements in the
classification system in his book Species plantarum (1753). He is regarded
as a great "reformer of plant and animal classification", and
also known as the gentle Prince of Botany. Instructional Strategy Spotlight: Timelines/Circle or Pie Charts When students read "The Perfect Storm", have them "create a timeline" that lists and describes the events from beginning to end. This is a helpful graphic organizer that helps "sequence events" in the text. 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
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