Plankton or Plastic, That is the Question

Eating low on the food chain is all the rage at the moment, and perhaps for very good reason.  Vegetarians have been extolling the virtues of a plant-based diet for years, even before the vegan camp got in on the act.  Eating your veggies and limiting meat is a common theme on green websites.  The undercurrents in the argument suggest that we can use less resources and feed more people with the acreage we already have under production. 

Plenty of animals just naturally eat low on the food chain despite being very large and complex creatures themselves.  Like baleen whales.  Or giant barrel sponges.  Or enormous decades-old Gorgonia soft corals.  Or manta rays. 

I had manta rays on the brain today for some reason.  Did you know that the reported maximum size for a manta ray is upwards of twenty-two feet?!  As I usually say, that’s four of my wingspans stacked end to end to end to end!   People are often impressed by the five foot disc size of southern stingrays here in Florida and the Caribbean but they’re hopelessly puny compared to the mantas. 

And yet, all they munch on is.. plankton.  Those perfectly awesome flaps on the sides of their heads are called cephalic scoops.  Not only do they funnel water down their mouths for filtration they also reportedly help steer these giant pelagic ocean-migrating rays.

But somewhere between thinking “Manta rays are so stinking cool I want to be one in my next life” and “I wonder how much plankton by weight they actually have to consume each day” I had a haunting thought.

Several lines of research into marine debris – trash in the ocean – in the last few years have pulled up some shocking finds from the ocean currents.  In some places in the world, when researchers have conducted plankton tows, small peices of plankton-sized plastic have actually outnumbered biological plankton! 

In the past I always thought about the upsetting effect this could have on the food chain as plankton were consumed by smaller fish and became integrated into the web.  And honestly I was most concerned with the idea of plastic contamination in commercial fisheries and in the food people eat. 

But if manta rays don’t have a way of excluding plastic from their filter feeding ways then they might be out there ingesting tiny peices of plastic even as you read this.  The same goes for blue whales, corals, sponges, and other planktivores.  The long term effects of this are anyone’s guess at the moment and I must admit I find the whole situation a harrowing prospect to consider. 

If this doesnt motivate you to recycle and reduce the plastic in your life and switch to reuseable grocery bags I dont know what will.  And finally, for a revealing look at the out-of-control nature of plastic in the oceans, check out More Plastic Than Plankton, a really intriguing installation made from plastic collected off Brighton beach in the UK in a one year period. 

Leaping Leviathans in Florida

 

For the second time in recent memory someone was struck in the Florida Keys after a ray lept from the water and into a boat.  Apparently tourists vacationing off Marathon spooked a spotted eagle ray that lept onboard, struck one woman and knocked her into the decking.  Unfortunately she died of the injury to her head. 

The CNN article makes mention of the infamous death of Steve Irwin in 2006 after he was barbed by a bull stringray in Australia, and it referenced the first leaping-ray-injury I can recall that followed shortly after Irwin’s death in September.  Apparently the first man, who was also in Florida at the time, did actually survive that experience. 

On top of the rays Florida has other leaping leviathans.  The Suwannee River caught national attention last summer when reports of sturgeon collisions surfaced.  In fact, Florida Fish and Wildlife reported twelve strikes over a forty-mile zone in the span of two years from the Suwannee to Manatee Springs. 

Its all enough to make you wonder what exactly is going on with the fish in this state.  We’re already seeing chatter on the interwebs and from the public that these things are signs of global warming, or pollution, or that the fish are out for revenge.  The truth is that it’s probably not the fish. 

Each of these events are considered to be freak accidents and the products of unfortunate timing and human reaction.  They’re coincidences.  Unfortunate events.  And we’re probably seeing more of them because of the steady increase of people who are out in Florida’s waters on a daily basis. 

The current estimates tell us that Florida’s residential population grows roughly one thousand people each day.  Each day.  Most move here for the weather and the natural beauty of the state.  Many eventually own boats or jet skis or participate in water related fun in some other way. 

The more people out on the water the more likely it is that we will see rare reports of strange events and sightings of animals that probably were unknown in state waters previously.  And the more likely it is that we will continue to see human and willdife interactions that lead to tragic circumstances for one… or both. 

Ultimately this is just one more legend, one more myth, that environmental educators may eventually need to dispel.  Stingrays don’t leap out of boats in a drastic effort to exact revenge.  Sometimes, there are no explanations for the things that happen in nature.  Hopefully, if these events can defy rationalization, then we can find ways to keep them from becoming sources of fear as well. 

What is it About Touch?

The field of education, as a whole, makes a remarkable effort to appeal to everyone’s dominant senses.  Some of us learn best through hearing, some through reading, and some through direct experience.  Its the last group that really gets spoiled in environmental education.  Math teachers may give you “manipulatives” to putter about with when attempting to solve algebra problems or figure out angles in geometry, but if you’re talking sea turtles, an EE teacher would probably pass a carapace (ahem, a shell) around the room. 

How can you beat that?  In many ways, you can’t.  Using artifacts from species is the only way to get your point across for so many different animals.  Sea turtles are usually unavailable to students and teachers.  And there’s species that are simply too dangerous.  Like white sharks.  Can you imagine taking a class on a field trip to South Africa so that they can touch white sharks as they breach?  I’d love to see the fine print on those permission slips!

But then there’s the species that you can actively bring into the classroom.  Living, breathing, moving, calling (and often pooping) animals for kids to interact with through… touch. 

So what is it about touch that breaks down the last barriers in learning and gives us that (often indelible) impression of animals and wildlife.  Why are we so enamored with the concept of touching what we see?  Do we just not believe our eyes?  Or does the whole phenomenon go deeper? 

We’re a very social species, obviously.  Even when we do not maintain close family networks we still, almost always, live near and gravitate to places where many other humans are present.  As a rule people are very tactile.  And, as a rule in our society, one of the last barriers that people will break as they build relationships with one another is… touch. 

I find this so incredibly interesting.  Why is touch the last barrier?  What is it about invading someone’s personal space (that three foot perimeter zone) that both breaks barriers and tends to generate stronger social ties? 

And what is it about touch that makes it leave such lasting impressions in our minds long after other elements of the experience have faded?  Why is it that I can remember the first time I felt a stingray but can’t recall what species it was?  Why are people so interested in touching wildlife that they will break laws and put themselves in danger to touch wild manatees and dolphins and alligators?  What is it about touch? 

I Brake for Tortoises

I heart gopher tortoises.  My best gal-pal Annie spent a large chunk of a year with the Student Conservation Association a while back working on habitat usage studies for desert tortoises in Nevada.  Apparently, her love of tortoises was infectious.  Shortly after hearing her stories of tortoise love and infaturation I became a sucker for them when I met Clyde and Shelly at the Brevard Zoo, a pair of gophers. 

These tortoises have adapted beautifully to the fire-driven landscape of scrub and oak hammock here in central Florida.  Their underground burrows can be extravagantly large (up to 35 ft is the average report) with various entrances and exits.  When flames dot the landscape, the tortoises even tolerate the presence of other wildlife seeking shelter from the smoke and heat. 

Unfortunately these turtles are threatened primarily by habitat loss and destruction in Florida.  As more of the coastal landscape is plowed under to make way for strip malls and housing complexes there is less and less available space for the gophers to use.  In fact, we have professional tortoise relocators here in the State so that developers can attempt to lessen their impact on this species.  The tortoises still lose ground, but most don’t lose their lives.  (At least its an advance over the older techniques employed, including burying the poor things alive in their burrows.) 

At present, one of the gopher’s worst enemies is the modern Floridian roadway.  Cars and trucks kill hundreds each year.  But, as most other coastal Floridians know, there is something motorists can do.

While its generally frowned upon to interact with wildlife in any way, if you see a gopher crossing a busy road, its perfectly legit to get out of your car to help them cross.  And that’s just what I did this past week. 

A few words of advice though, for all you would-be tortoise rescuers:

• Try not to cause an accident when you brake.  I nearly caused a pileup and I’m fairly sure my insurance wouldn’t accept the “but there was a gopher tortoise in danger!” explanation.
• When you pick them up, pick ’em up by the side of the shell (or carapace if you want to sound nerdy).  They’re herbivores but their beaks are sharp and they will bite!  Also, hold them flat in the air with their belly pointing towards the ground.  Tipping them towards the sky can put pressure on their internal organs and stress them out needlessly.
• Third, make sure you carry them to the side of the road where they were headed, not where they were coming from.  The stubborn little things have been known to march right around and attempt to re-cross the road if you returned them to their point of origin. 
• And finally, watch out for the hind end.  Like many other species gophers will poo on you just as they would poo on a potential predator to attempt to persuade them that they’re not a great meal.  Tortoise poo is pretty stinky so steer clear!

I hope the male I helped across Lake Underhill enjoyed a day full of delicious scrub and pine and has a long and happy life.  He did try to take a chunk out of my hand, but I really can’t blame him.  Imagine for a moment that a 30 ft. beast randomly picked you bodily off the ground, carried you for a few moments, and then arbitrarily put you back down.  I don’t know about you, but my heart would be pounding! 

Finally, a little shameless self-promotion: The Marine Photobank project continues to impress and inspire me and I was rather thrilled to see a link to my contributions in the Feb. 2008 MPB Bulletin.  I really wish my night-kayak photos of phosphorescent algae had developed from last night, but hopefully in the near future I’ll have many more interesting things to contribute!