Author Archives: George Rogers

Everybody…get in your niche!

Today John and George visited the wading birds in Savannas Preserve State Park.  What a photo op!  John took the Snowy Egret action photos, and I took the others under John’s photo master supervision enjoying the use of my ancient and just-repaired 1970s reflector lens adapted happily to a modern camera.

I’m pink and I dabble.

There’s something about a marsh to make you think of the big picture, maybe because you see so much at once: the open primitive diorama underscoring those big wading birds as the modern-day dinosaurs they are.   Bird diversity helped Darwin envision evolution, so today John and George were 2015 Darwins.   If Darwin hadn’t figured it all out back in the 1830s, we should have today because Darwin’s Finches having nothing on the Savannas Egrets.

A Spoonbill goes around with a shovel on its face, walking along…sometimes rapidly…dabbling and swinging its bill from side to side like an elephant’s trunk. The beak looks like one of those wooden ice cream paddles in the little paper lunchroom tubs. Spoonbills eat anything from vegan to squirmy.   When the bird senses food the spoon snaps shut, and water drains out the sides leaving a tasty treat for Mr. Pinky to eat.

Yo buddy,  you stick to your niche, I’ll stick to mine, and there won’t be no trouble.

Mixed in today’s flock were Great Egrets and Snowy Egrets.  There could be a competitive situation here.  But Mother Nature is on top of that.   She wrote the “Competitive Exclusion Principle,” decreeing that no two species occupy the same niche. The big wading birds may seem to have similar competing needs,  but competition breeds specialization, like the ecosystem of diversified shoe stores in the Treasure Coast Mall.    Today’s Egrets have détente with Spoonbills.  While Spoonbills eat with spoons, Egrets prefer harpoons.

Great Egrets are easy to photograph because they hold still until they spot a tasty fish, then snap, the sharp yellow dagger stabs like lightning.

Great Egret waiting patiently and posing for portrait.

The similar Snowy Egret, with rakish hair-do and a black beak has its own non-compete clause.   Rather than ambush large prey, it does the “stingray shuffle” or flaps around stirring up such lunchables as amphibians, insects, worms, crustaceans, or small fish. Snowy Egrets can hunt in groups and “round up” the menu as the birds dance around.  Below those black legs are yellow tootsies. According to some accounts, the birds while flying dangle those yellow rakes down into the water to frighten the fish upward for an easy catch.

This photo and next, dancing flapping Snowy Egrets with their yellow feet.

So today’s bird party was a gregarious jumble of spooners, ambushers, and a yellow-toed wolf-pack each doing its own thing. Opportunity for everyone.

To go one paragraph further, the plants seem to do the same. Marshes can be quilts where single species form acre-sized patches.   The borders between the patches are often sharp, or not.   Why do marsh species often sort into monospecific stands?

I think about that at Wakodahatchee Wetlands and Green Cay Wetlands, vast constructed marsh areas of shallow reclaimed water. These two sites with full sun, constant water, and nutrients galore nourish millions of grateful marsh plants in a conditions “as good as it gets.” They do not have 100 per cent perfect conditions, as there may be limited oxygen in the mud, maybe some toxins in the water, or odd nutrient imbalances, but let’s pretend a shallow sea of fertilized sewer water is the perfect setting for those species thriving there. Great blankets of pickerel weed, arrowhead, bulrushes, spike-rushes and others look like a giant paint by number composition.

We might think the big species patches may merely represent each spreading out (most of them have rhizomes) from random points of origin until they bump into another patch—like expanding bacterial colonies after sneezing into a petri dish.  But it’s not so simple.  In the Google Earth helicopter view of Green Cay below, the species patch pattern relates to borders, structures, canals, cypress domes, and other physical variations an observer can see, let alone physical influences too subtle to spot.   Some species compete better along the boardwalk, some near the wooded hummocks, some near open water. There’s competitive exclusion afoot.  Even aggressive rhizomatous marsh species seem to divvy up the seemingly near-uniform wetland into divergent niches.

Green Cay, the species patchwork isn’t random. It seems related to the boardwalk, waterways, and islands.

Merremia dissecta

Convolvulaceae

It is with extreme sadness, I must note the passing of our wonderful blog friend Mary Hart.  Some readers may recall her participation in the blog a year ago and more from Worcester in the U.K. where she had been confined to a wheelchair.   Mary was a botany student in my program during the early 90s at the University of the West Indies, Barbados, and was an avid horticulturist and naturalist, smart as a whip, a basketball fan, and a ton of fun.  She is missed. 

After some time away, John and George revisited Seabranch State Park yesterday to preview a nature walk we plan to lead there tomorrow.   Greeting visitors at the park entrance, climbing in the low scrub vegetation, is a weedy-looking morning glory vine with some history and mystery.   (Most of what I know that history comes from a 2007 article in the journal Economic Botany by the late morning glory expert Professor Dan Austin.)

Noyau literally means, “nut.” In the Caribbean context the term refers to almonds.  You guessed it. Noyau vine is almond-ish.   Not that that’s good for those who think the joy of wild plants is to eat them; essence of almond is associated with cyanide, just as in apple seeds and those laetrile apricot pits.

Noyau Vine (By John Bradford, this and the next are file photos not taken yesterday)

But a little toxicity never gets in the way of plant uses; in fact poisonous-ness flags medicinal applications.  As Dr. Austin documented,  Merremia dissecta has served the variety of purposes in traditional medicines, flavoring, and even as a root food in Argentina, presumably prepared to free the entrée of cyanide.

As with so many bioactive plants, the historical medicine cabinet is boring and redundant, although ointments against skin ailments ring plausible as cyanide-based toxicity obviously may grant antibiotic powers.

What I find more interesting than the individual uses is a broader implication based on the breadth of uses:  People move useful plants around, and this creates complications in branding species as native or not native to any given region.  There are many cases perhaps where such designation should not occur, and we have before us a good example.   When you don’t know, you don’t know.

Is noyau vine a Florida native?  Look in different books and find different answers.  Should we rogue it out with malice as an abominable invasive exotic weed?  Or is the vine a native ethnobotanical treasure?   Without the possibility of certainty,  Dr. Austin tilted toward the latter, and I’m aboard on that.

Given that the species is native around the Caribbean Basin, there’s a fair chance it arrived in Florida free of human help.  To make little more interesting, of course there has been commerce around the Caribbean Basin for a very long time before Columbus spoiled the fun, although the degree of involvement of Florida in pre-Columbian Caribbean commerce is an open question.   Could it have come in a canoe or around the Gulf of Mexico from points south and west?  Sure.  We can ask the same about papayas, agaves, and more. William Bartram encountered the vine in Florida in the late 1700s.  How did it get around so early?  Non-human dispersal?  Native Americans?  Early Europeans?  A combo?

Whenever the original geographic limits,  noyau vine now with the help of people is worldwide in warm climates, and even some that aren’t so hot: Pennsylvania, Arizona, Africa where it has developed an ethnobotany of its own, and even Australia as a weed.

On tomorrow’s nature walk, we won’t eat any, but we might smash it up and see if it smells like almonds.