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Sunday
Nov142010

Sometimes *they* look at us too

Check out this cool bit of footage from our recent research visits to Mexico to study whale sharks with the Georgia Aquarium team.  We were diving under a large aggregation of whale sharks when one of them broke from the surface to come and visit, checking out first one diver, and then the other, possibly attracted by the bubbles.  Whale sharks normally cruise around at the surface, largely indifferent to human presence except for occasionally rolling their eye across you as they pass, but this one was clearly interacting with us.  Colleague Betty Galvan tells me about a small (if 4m could be considered small) female that followed her for 20 minutes in Honduras one time, so interactive she described it as being like a puppy.  I suspect, when conditions are right, whale sharks can be curious or even inquisitive critters.  Its hard to prove, but I don’t think there’s much doubt from the video.  The aquarium has been conducting a behavioural study on the collection animals for some time, but more work on their behaviour in the natural setting is desperately needed.  Hopefully the aquarium study can refine the techniques needed to get out there and understand what they do in the field.

 

You can follow my YouTube channel here, or the aquarium’s channel here. Footage Copyright 2010 Bruce Carlson/Georgia Aquarium and used with permission

Sunday
Nov142010

Science Online 2011

I was interested in meeting some other online science folks and I had heard through the twittoblograpevine®  that the Science Online 2011 conference registration was opening soon, so I marked my calendar with a reminder to register.  Come last Wednesday at 12 o’clock, sure enough off goes the alarm.  I sidle over to the site and register on my lunch hour, figuring that if I put it off I might just forget.  My registration goes through at 12.37pm and after its done I note that I am number 223 in the list of attendees.  What, what?!  223 people in 37 minutes?  Next thing I know, I get a Tweet that registration is closed, sold-out at the maximum 300 participants at 12.44.  Yikes!  Either online science folks are über-connected, or this is one seriously popular conference. I suspect a bit of both, but I never guessed that registering would be like 14yos trying to score tickets for a Justin Bieber concert.

Thank the Flying Spaghetti Monster for Outlook reminders, I am one of the lucky ones.  I signed up to teach a workshop on Prezi, my favourite presentation software (Powerpoint is dead to me).  And Research Triangle Park NC, I’ll see you in January 2011.  I am already working on some good Aussie sea shanties to contribute…

Saturday
Nov132010

Slow down = mow down?

This post was chosen as an Editor's Selection for ResearchBlogging.org

ResearchBlogging.org

Manatees in Florida are a battle hardened lot.  A large proportion of the sluggish sea cows have injuries from boat strikes, which is something of an occupational hazard when you live in the heavily trafficked coastal waterways of the sunshine state.  Indeed, lots of manatees have multiple scars from a lifetime of encounters with leisure craft, and boat strike is the biggest human cause of manatee deaths in that state.  The solution seems obvious, right?  Slow down!  Give the manatee a chance to get out of your way, and maybe human and manatee can live together, sharing the coastal waterways in relative harmony.  But what if that’s exactly the wrong thing to do?  What if that makes things worse?  How could that be, and what should we do instead?  Science to the rescue…

When legislation was first introduced to slow coastal recreational boats in manatee habitat, the number of boat strike injuries went up, yes up. Significantly.  Enter acoustics experts Ed and Laura Gerstein.  Through a painstaking research program into the hearing capabilities of manatees and the soundscape of Florida waterways, the Gersteins teased apart the problem and showed its surprising and counterintuitive basis.

The research began with studies to determine what a manatee can hear.  This is not as easy as it might seem.  We’ve all had audiograms done: they put you in the little booth with the headphones and ask you to press a button if you hear a sound.  They systematically play different frequencies at different amplitudes and, by your button, you paint a response curve for them about what you can and can’t hear.  Well, with manatees, the principle is the same, but the execution was a bit different, because you can’t ask a mantee whether or not it heard a sound.  Or can you?  Actually, you can train a mantee to push a paddle with its nose when it hears a sound (in exchange for a monkey chow biscuit), using the same training approaches as any mammal training.  Once the manatee has that behaviour down reliably, you can play it, under controlled conditions, all the frequencies and amplitudes of a typical audiogram, and thus determine what it can hear.  Its a great example of training (operant conditioning) as a research tool.  It took the Gersteins over a year at the Lowry Park Zoo in Tampa to train two manatees to do this, and 4 more years to complete the sound study, but the resulting audiogram held the key to unlocking the boat strike problem.  The Gersteins showed that manatees are not very good at hearing low-frequency sounds and that their peak sensitivity to sound is up in the 14-16KHz range (which would be audible but very high to human ears). 

 Next they went to the waterways and measured the ambient sound and then the sounds of boats traveling at different speeds.  And there it was, the answer:

What a manatee can hear is represented by the grey line - if its above the line, then they can hear it, if below, then they can’t.  Thus the background noise (the black line) is below what a manatee can hear - they live in a largely silent world.  A 27ft recreation powerboat zooming by right overhead is the red line - they can certainly hear that!  The same boat when its 16 seconds travel away (the pink line) cannot be heard yet.  But heres the kicker: slow the boat down to 3mph (5kmh - the blue lines) as the law requires, and the response curve drops below what a manatee can hear, even if the boat is right on top of them.  Slowing the boat down means that you’re effectively sneaking up on the hapless mammal, so that they never know what hit them.  The effect is exacerbated by two other things.  Firstly, a slower boat not only makes less noise (its “quieter”) but it also makes lower frequency noise (basically, it rumbles, not whines) and as we saw earlier, manatees don’t hear well down in the low frequencies.  Secondly, to make it even worse, there’s something called the Lloyd mirror effect, where low frequency sounds are muffled or even cancelled out completely in  shallow water, because the sound waves reflect off the surface of the water and the bottom and negate each other in the water column.  The sum of these three factors - boat amplitude, boat frequency and Lloyd mirror - is that manatees are effectively deaf to recreational boats in shallow water.  These results also explained why manatees also get hit by barges, which are large and move very slowly.  In another study, the Gersteins showed that this was made worse by a sort of sound shadow that occurs in front of a barge because the propellers are at the back and their sound proagates behind, but not in front of, the vessel.  Thus even a large and slow barge can still sneak up on a manatee.

Never fear, this story has a happy ending.  The Gersteins have taken the knowledge they gained through this elegant research and turned it into a solution to the problem: a device that can be attached to the front of every boat to emit an alarm sound that manatees can hear and thus avoid.  In this endeavour they’ve been sensitive to the problem of “sound pollution” in the coastal environment.  By using flanking ultrasound emitters, the device focuses the alarm sound in a 6 degree wedge in front of the vessel, making what Ed describes as a “laser of sound”.  Validation studies are showing that manatees in the vessel path do hear the alarm and take evasive action and that, importantly, this effect doesn’t wear off.  In other words, they never grow accustomed to or ignore the alarm sound.

This seems to me a great example of science showing that the obvious (slowing down) is not always the correct course of action in a complex world.  It reminds me of well-intentioned minimum legal size limits for recreational and commercial fisheries, which can cause fishers to take the largest and most fecund fish in the population or, worse still, take all the females in those species that change sex as they grow.  Through careful and time consuming bioacoustics research, with a healthy dose of animal training in an aquarium setting, the Gerstein’s may well have helped save countless manatees from future harm.

Gerstein, E. (2002). Manatees, Bioacoustics and Boats American Scientist, 90 (2) DOI: 10.1511/2002.2.154

Thursday
Nov112010

Can you ID this jellyfish?

In Mexico this summer we came across a nice jellyfish and scientist/videographer Bruce Carlson caught some footage.  I admit that Scyphozoans are a real weak point for me.  Can anyone identify this for us?

 

Elegant little thing, right? See more videos on my YouTube channel

Thursday
Nov112010

Good news everyone! </Prof. Farnsworth>

 Dr. D.’s class at Creekside Elementary School in Milledgeville GA will be getting their aquarium project materials through Donors Choose plus bonus aquarium equipment kindly donated by Georgia Aquarium because we finally got them over the funding  line!  It was a scoche late for the official Ocean Bloggers United for Education campaign, but its more important that the kids got funded.  So thanks to those who helped, and to everyone else - next year I’m comin’ to get you…

Readers of this blog helped two education projects complete their funding goals by donating over $200.  That means that 460 students will learn about marine science in 2011 and beyond, studnts who otherwise would not have had that opportunity.  I am thrilled to have been part of the endeavour and have been amazed at the amount of giving spirit among readers and the other ocean bloggers.  Everyone should send special love to DeepSeaNews who coordinated the OBUE campaign.

The prize winners from the first projects I targeted will hear from me as soon as the final numbers are olffically tallied.

Thanks folks - Rock on!

Tuesday
Nov092010

Man vs. Fish - amazing remora video

Most people consider remoras to be no-good hangers-on, sponging off well-meaning marine megafauna. But on one of our research trips to Mexico to study whale sharks this summer, one of the staff divers, Elliott Jessup, had an incredible encounter with one of the most inquisitive fish any of us have ever seen, and scientist/videographer Bruce Carlson caught the whole thing in HD. The waters were full of whale sharks and their attendant remoras, when this little guy took leave of his usual hosts and instead took a real liking to Elliott, even attaching to his butt, and eating his hair.  Learn more about our whale shark research here and you can follow my YouTube channel here and the Georgia Aquarium channel here.

The footage is copyright 2010 Bruce Carlson/Georgia Aquarium and used with permission. 

Tuesday
Nov092010

Follow this NOAA expedition on a new "Deep Corals" blog

Lophelia, a deep sea coral.Fun news from colleague Andrew Shepard at Harbo Branch (Florida Atlantic U.), via Kim Morris-Zarneke:

“Tomorrow, Nov. 9, 2010, the NOAA ship Ron Brown departs Pensacola, FL, on the Extreme Corals 2010 Expedition. Chief scientists, Steve Ross, UNCW, and Sandra Brooke, Marine Conservation and Biology Institute, lead the effort to explore and characterize deep coral ecosystems from the West Florida Shelf to the northern Florida east coast using WHOI’s Jason ROV. We have set up a Web portal for the expedition at http://cioert.org/xcorals. The NC Museum of Natural Science is partnering on this web offering, providing access to daily blogs from sea, image gallery, education materials and more at http://deepcoral.wordpress.com

Monday
Nov082010

Last chance to be part of the amazing 2010 DonorsChoose push - what are you waiting for?

The Ocean Bloggers United for Education campaign at Donors Choose ends tomorrow 11/9/2010 at midnight.  So far we’ve made great progress; between the various ocean bloggers we’ve raised $548 and will reach 557 students through the programs we’re supporting.  If you want to get inspired, get over to Deep Sea News and read their summary on progress to date. 

But we’re not quite done yet.  There’s time for one last push to get Dr. D’s class at Creekside Elementary school an aquarium so that they can learn about life in the water.  If we get them the last little way ($95), then Georgia Aquarium will generously donate additional aquarium equipment, like a matching gift.  They’re offering it, but we’ve got to come up with the 95 bucks first!  Please, go to the page for this project and donate today. 

If you need any more motivation, check out what Mrs. L. had to say after the readers of this very blog raised enough for her class at East Paulding Middle School to do their Mirror Universe project:

Dear Zier Niemann Consulting, Eddie, Gramma Hahn, Susann, The best BooBoo there is!, Al Dove, Natasha Wilks, Christy and Disney’s Planet Challenge, 

I can’t fully express my joy, excitement, and thanks for your donation to my project. It is great to see that you share my vision for reaching children. In Science, we so often use abstract explanations to explain abstract things.

The tools that you have funded will enable students to create ocean currents and see the amazing features of the ocean floor. I know the simulator will help them have a better understanding of the ocean. By being able to trace the features on the globe and hold pieces of the ocean floor they will be able to touch things that they could only read about before..

Thank you so much. I can’t wait to introduce these tools to my students. Teaching and learning about the ocean will be more fun because of you.

With gratitude,Mrs. L.”

There’s few things in this world more important than education.  Georgia has some room to improve in this regard, and Donors Choose is a great way to create action at the grass roots level.  Please help - the kids need you!

Wednesday
Nov032010

Whale shark research on National Geographic

Georgia Aquarium’s whale shark work from Mexico this summer is featured in a story by Jodi Kendall on the main web page for National Geographic’s new show Great Migrations. Cool!

Tuesday
Nov022010

Carnival of the Blue #42 - Life, the Universe and Everything

Pete Strutton’s account on this blog of the history and significance of ocean fertilisation as a possible way to combat global warming is part of the latest Carnival of the Blue over at Oceana’s blog The Beacon.  You should check out what else they have cooking: oil spill research, salmon fisheries, MPA’s, and the census of marine life.

And here’s news: carnival #43 will be right here on DeepTypeFlow!

Tuesday
Nov022010

Circus of the Spineless is up!

The 56th Circus of the Spineless is up over at Jason Robertshaw’s Cephalopodcast blog, and DeepTypeFlow is part of the party for the first time. CotS is a blog carnival bringing together recent blog posts about invertebrates from all over teh interwebz.  Check out some of the fine contributions here.

Monday
Nov012010

Seeing the world from a whale shark's point of view

My ECOCEAN colleague Brad Norman has been deploying Crittercam on some whale sharks in Exmouth, Western Australia.  I always wanted to try that; I’m so glad he did it!  The footage is now on National Geographic.  There’s a bit less actual Crittercam footage in the story than I would have liked, but thats just my own anxiousness to see what they see!  My guess is that a lot of it was much like the snippets shown - slowly cruising near the surface. 

I would LOVE to see what they see approaching food patches, or when they see another whale shark, or on one of their mysterious crepuscular dives (might need some supplemental lighting for that one).  Its a great start.

Monday
Nov012010

Who you calling a crackpot scientist?

There’s an interesting article in the South African news media about a UN moratorium on the sort of geo-engineering ideas described in my recent discussion with Pete Strutton.  The general gist of the moratorium is that the UN is saying “lets not do any more of this sort of research until we have a better idea whether its going to work and at what cost”; its not an ethical prohibition in the sense of the human cloning sort of ban.  Consequently, the South African piece describing proposers of geo-engineering as “crackpot scientists” is absurdly harsh and sensationalist journalism at its worst.  I can say with confidence that scientists studying geo-engineering concepts are simply trying to propose solutions to what will certainly be the most vexing global challenge of our generation.  As stated in this Scientific American piece:

Major scientific organizations — including the American Meteorological Society, the American Geophysical Union and the U.K. Royal Society — have issued cautious calls for more research, though warning that geoengineering approaches shouldn’t supplant efforts to cut greenhouse gas emissions.”

In my ideal world, it would be a social norm that you can’t object to an idea unless you propose a justifiably better alternative.  Certainly there are questions to be answered about who gets to make the call on these global-level solutions (even mentioned here back in March).  But as it stands, with Kyoto and Copenhagen essentially failing to effectively retard the source of the issue (greenhouse gas emissions), we can ill-afford the UN to be hindering research into possible solutions, without offering something better.

Wednesday
Oct272010

Georgia Aquarium work featuring on Nat Geo

Some of the work being done at Georgia Aquarium is featuring on National Geographic’s Inside Wild blog lately.  Check out some of these:

Manta Ray training - Dennis Christen and other training staff talk about what it takes to train the giant rays

Invasive Lionfish - biologist Heather Dziedzic discusses the spread of the beautiful but destructive lionfish throughout the Atlantic states and Caribbean

Giant Pacific Octopus - features a nice photo of the aquarium’s octopus

Also, check out this recent news story about how whale sharks feed, which is based on the same paper I referred to in a previous post.

 

 

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