December 8, 2008
Because of last year's Hurricane Dean, hotels along this stretch of the Costa Maya need carpenters, not naturalist-writers, so here I barter work on odd jobs in exchange for internet connection, some food and a spot on the beach for my tent. The other day I was sitting behind the workers' hut stringing sea-beans and bamboo sections to form a kind of curtain when behind me, out in the hurricane-mangled mangroves, I heard a loud, nasal WAH WAH WAH. A white raptor perched conspicuously on a snag jutting above the mangroves and stayed there until I got my camera. You can see the resulting picture of a truly handsome bird at http://www.backyardnature.net/n/08/081208lf.jpg.
That's a Laughing Falcon, HERPETOTHERES CACHINNANS, and you'll understand why it has that name if your computer can digest WAV audio files, and you point your browser to http://www.naturesongs.com/lafa3.wav.
If you can't do that, imagine a big crow mimicking a fat, jovial man breaking into unrestrained belly- laughter, and that's it. Howell refers to it in A Guide to the Birds of Mexico and Northern Central America, as maniacal laughter.
Some raptor species are hard to distinguish from others, but Laughing Falcons are distinctive and unmistakable. Also, they're fairly common in a variety of habitats ranging from forests to savannas, and they're distributed from Mexico to Argentina, so this is another of those species "emblematic" of the American tropics.
The most common shorebirds along the beach in front of Mayan Beach Garden are Ruddy Turnstones (bigger and dark) and Sanderlings (smaller and gray). You can see a turnstone running along the water's edge at http://www.backyardnature.net/n/08/081208rt.jpg.
Ruddy Turnstones, ARENARIA INTERPRES, are nice looking birds even in their winter plumage, but in their summer plumage they're really striking with their harlequin faces and warm, rusty-red backs and bright- red legs, as shown at http://www.gpnc.org/ruddyT.htm.
Turnstones, about the size of Wood Thrushes, are named after their habits of turning stones -- walking down pebbly beaches and flipping pebbles aside to nab what's below them. Field guides show their beaks slightly upturned for facilitating the pebble-flipping action, and I've seen such upturned beaks in a few birds, but most turnstone bills I see are straight, just like the ones in both of the above pictures. Here they don't really need beaks adapted for pebble- flipping since along our beach they just probe in sand and, at low tide, seaweed mats.
It's worth noting the Ruddy Turnstone's summer distribution in North America -- Alaska's western and northern coasts, the coasts of Canada's northernmost islands, and northern Greenland's coast. Just think: That little bird in my picture has just flown from deep in the Arctic to this tropical beach!
Ruddy Turnstones are "holarctic breeders," which means that they nest in Arctic regions of both North America and Eurasia. In North America the species overwinters on coasts as far south as southern South America, so the ones here are actually somewhat close to home, relatively speaking!
I identified my first Sanderlings, CALADRIS ALBA, on a windy, finger-numbingly frigid February morning at Jones Beach on Long Island, New York, in 1976. I still remember the problems with my binoculars frosting up, and my frustration over being unable to definitely see any good field mark for these gray, fast-moving, nervous little birds. You can see what a hustling little flock looks like chasing a wave back to sea -- moments before they turn around to be chased by the next wave back onto the sand -- at http://www.backyardnature.net/n/08/081208sd.jpg.
Eventually I figured out their identity and what their field marks were. For one thing, their behavior is somewhat distinctive, keeping in small groups chasing waves back and forth on sandy beaches. Also, they're small and very pale gray. Finally, the thing I look for to confirm the ID is a white patch extending into the dark-gray mottling in front of their wings. In my picture the bird in the lower, right corner shows the white spot very well.
Cornell Lab of Ornithology's page on the Sanderling here describes Sanderlings as among the most widespread wintering shorebirds in the world, found on nearly all temperate and tropical sandy beaches throughout the world. Among shorebirds, only the Ruddy Turnstone and Whimbrel rival its worldwide distribution.
Howell reports Sanderlings as common winter visitors in Mexico from August to May -- all months except June and July! Sanderlings seem to live mostly in their "wintering grounds," only making brief yearly forays into the Arctic to breed.
At http://www.backyardnature.net/n/08/081208su.jpg you see something found occasionally along the beach here. Can you imagine what it is -- animal, vegetable or mineral? The first time I found such a thing I was completely stumped until one day one turned up bearing long, slender, black spines weakly attached to each bump on the shell's surface. Instantly I realized it was a sea-urchin -- or rather a dead sea-urchin's bleached, de-spined shell.
Living sea-urchins look like the business ends of medieval battle-maces. A living one is shown here.
In fact, the one shown above, Lytechinus variegatus, may well be the species whose shell I've photographed. I'm basing that on a tentative ID made with a reef- animal field guide found in the hotel's reception room.
Wikipedia does a pretty good job providing an overview of sea-urchin life history at http://en.wikipedia.org/wiki/Sea_urchin.
USING THE PHYLUM CONCEPT FOR BEACH IDS
Sea Urchins are Echinoderms -- members of the Phylum Echinodermata. Phyla are very large taxonomic groupings. The phylum is the main division below the kingdom, of which plants belong to the Plant Kingdom and animals belong to the Animal Kingdom. Among animals, all animals with a spinal cord constitute the phylum Chordata, so in that sense Echinoderms are as distinct from all other animals as all vertebrate animals are from the various kinds of non-vertebrates.
Beach-found organisms are so diverse that often when you're trying to identify them it's helpful to think in terms of phyla. In fact, field guides to creatures found in tropical reef ecosystems typically group their animals according to phyla. In the field guide "Reef Creature Identification" by Humann and DeLoach, animals described are placed in the following groups and phyla:
- Sponges: Porifera
- Cnidarians: Cnidaria
- Comb Jellies:
- Flatworms: Platyhelminthes
- Ribbon Worms: Rhynchocoela
- Segmented Worms: Annelida
- Crustaceans: Arthropoda
- Bryozoans: Ectoprocta
- Mollusks: Mollusca
- Echinoderms: Echinodermata
- Tunicates: Chordata
When I was trying to figure out what my sea-urchin shell was, once I referred to the above list I was quickly encouraged to consider the echinoderms simply by the process of elimination.
Having left the Yucatán Peninsula's scrubby, weedy interior I thought my morning-glory-describing days were over, but as soon as I got here I saw a morning- glory species that just can't be ignored. It's the Goat's-foot Morning-Glory, also called Beach Morning- Glory, Railroad Vine, Bayhops and lots of other names because it's found in tropical areas worldwide. It's IPOMOEA PES-CAPRAE, the genus Ipomoea being the main morning-glory genus, and "pes-caprae" being good Latin for "goat's-foot." You can see what's goaty about it at http://www.backyardnature.net/n/08/081208ip.jpg.
The leaves are shaped like goat hoof-prints.
One striking feature of this species is its rampantly rambling manner of spreading across naked, searingly bright, hot, white sand, as shown at http://www.backyardnature.net/n/08/081208iq.jpg.
That's the sand road I jog on half an hour each morning before the sun comes up. Nearly all the greenness there is Goat's-Foot Morning-Glory. Notice how vehicles keep the vines pruned by running over their tips. The tough, evergreen vines sprawl up to 30 meters (100 feet) across the sand! In the picture you can see what enormous service the vine contributes to local ecology: It stabilizes loose sand. In dune areas it fixes dunes in place, but here we have no dunes so it's doing its best to steady sand mounds along the road put there by machines clearing the road after Hurricane Dean.
This robust species may well survive the current man- made mass extinction. It's salt tolerant, stands a lot of heat and physical abuse, plus it's floating seeds makes the species one of the best-known examples of oceanic dispersal.
In Brazilian folk medicine Goat's-Foot Morning-Glory is used to treat gastrointestinal disorders.
I have nothing but nice things to say about Goat's- Foot Morning-Glory, but I can't write some of the nasty thoughts I've had about the big, flat clumps of Coastal Sandbur that's also very common here, in the same ecological setting as the morning-glory. You can see a sprawling, six-ft-across Coastal Sandbur at http://www.backyardnature.net/n/08/081208ch.jpg.
That's CENCHRUS SPINIFEX, a real grass in the Grass Family, and what's so cussed about it is clearly shown at http://www.backyardnature.net/n/08/081208ci.jpg.
Those are grass flowers abundantly armored with stiff, very sharp spines which themselves are mantled with minute, backward-pointing spines. When a sandbur punctures your skin, because of those backward- pointing spines, pulling it out becomes a miserable experience. If you're not thinking, when you realize the bur is resisting being pulled out, you squeeze it harder to get a better grip, and end up with stuck fingers, and with those backward-pointing spines on the spines, there's simply no nice way of getting unstuck.
Though Coastal Sandbur is native American, even found in sandy soils throughout much of the US Southeast, it's invading other countries. A website in Ukraine says that in that area up to 300 plants can occupy a square meter, and that the species "...harms sheep farming, because prickly seeds cling to the sheep wool and sharply reduce its quality. When eaten by sheep, they damage mucosa and cause ulcers and tumors." That's not to mention what happens to barefoot beachwalkers here. Of course even this species provides a valuable service to the beach ecosystem, for its broad mats also stabilize the sand. I wouldn't be surprised if it also protects other plant species growing nearby by causing herbivores to steer clear of the whole area.
If you look closely at the above picture you'll see that the bur on the left is topped by dark brown, elongate male anthers, while the bur on the right is topped by pale, fuzzy, female stigmas. The spines below these flower parts arise from the flowers' involucre, or collection of bracts, or modified leaves, growing immediately below the two flowers.
I continue to be astonished at the variety of chili peppers found in people's gardens here. I've told you about tiny, super-hot Chili Pequín (still online at http://www.backyardnature.net/q/chili.htm) In the little garden next to the hotel there's another kind of tiny, super-hot chili pepper known locally as "Chili Payaso," or "Clown Chili." It's shown at http://www.backyardnature.net/n/08/081208cc.jpg.
One person says the clown part of the name arises from the shape and color of the chili, like a clown's nose, but Doña Lupe, the cook, says the chilis are called "clown" because they turn different colors, first green, then yellow, then orange, and finally red.
Doña Lupe says that Chili Payaso isn't too common around here, and that she thinks our plants are from seeds brought up from Belize. She says that Chili Payaso can be used interchangeably with Chili Pequín -- anytime you need something that's tiny and really, really hot.
WHAT POISONWOOD JUICE DID TO MY SKIN
You may recall from my November 17th Newsletter that in much of the Yucatán we have a tree called Poisonwood, Che Che'en in Maya, and Metopium brownei technically. Its sap is famous for causing skin irritation ranging from rashes to running sores. Poisonwood is a member of the Poison Ivy Family so that explains part of the problem. Read more about it at http://www.backyardnature.net/yucatan/poison-w.htm.
When I took the picture for the above essay I conducted a little experiment. I broke off a Poisonwood leaf and daubed a single droplet of juice onto the inside of my left wrist. The instant before I applied the juice I paused a moment, however, because exactly where I was about to daub the droplet there appeared a small, circular, white scar. This scar remained from when I conducted the same experiment with Poisonwood sap about 15 years ago when I was serving as a naturalist at a lodge in Belize. This time I put the droplet a little to the side of where I did earlier, so now I'll have two white spots.
You can see documentation of what happened to my wrist at http://www.backyardnature.net/n/08/081201mm.jpg.
In most of the area where Poisonwood grows there's typically another tree growing nearby known in Maya as Chakah, in English as Gumbo-Limbo, and to tourists as "Naked Indian Tree." It's Bursera simaruba. The sap of this tree serves as an antidote to Poisonwood juice. You can read more about Gumbo-Limbo and see its trunk at http://www.backyardnature.net/q/bursera.htm.
Curiously, in Yokdzonot most people didn't regard Chakah/ Gumbo-Limbo as an antidote to Poisonwood sap. They used juice from bitter-oranges, which works perfectly, they said. This causes me to believe that Poisonwood's sap is caustic with a high pH, and that anything acidic, with a low pH, might neutralize the sap. However, belonging to the Poison Ivy Family, maybe Poisonwood also causes an allergic reaction, so I'd be careful experimenting with it. I'm not allergic to Poison Ivy so I couldn't test that aspect.
COLLAPSED DREAM HOMES & LOST TENT PEGS
I sleep on the beach most nights but when it's rainy I peg my tent in buildings whose walls were bashed in last summer by Hurricane Dean. When I'm hunkering in these dream homes sometimes I imagine the owner on stormy days or maybe even during lesser hurricanes before Dean, sitting calmly in his overstuffed chair smoking cigars, sipping whiskey, grinning to himself in cozy security as wave froth plasters his big picture window facing the sea -- grinning at how the palms bend to the sand while in his sanctuary all is peaceful, all under control.
But, no one built anything along this beach with Texas-sized Hurricane Dean in mind -- nothing to withstand wind gusts of 200 mph (320 km/h) and the enormous waves that came with them. You should see the slabs of concrete strewn like big eggshell flakes. Seeing the destruction, you're put in mind of how vulnerable we humans really are, and how silly we are when we begin feeling invincible, secure at last.
In fact, when you walk the beach a lot, you find that almost any little event leads to a long train of thought following that same general line.
For instance, the other night I'd pegged my tent on the beach and the next morning found myself missing a tent peg. Thing is, I know how easy it is to lose tent pegs in sand and I really dislike losing them, so here I've been counting my pegs when I put them into my bag, counting them when I take them out, and I pay strict attention to each spot where I peg them. It's basically impossible to lose a peg with such a conscientious monitoring system, but... I've lost TWO pegs this week...
Beach walking, brooding over lost tent pegs, my thoughts eventually led to the claims of nuclear power engineers that -- although already very serious accidents have happened -- it's impossible for nuclear accidents to occur in their power plants. Well, nuclear power stations are more complex than tent pegs and sand, but I doubt that nuclear engineers can have any more confidence in their monitoring systems than I had in mine. But, when I'm wrong, I lose tent pegs; when they're wrong, the planetary biosphere is poisoned for thousands of years with DNA-shattering low-level radiation.
I wish that each person who ever finds himself or herself in the position of being able to gamble with Life on Earth, or with the welfare of their nation, tribe or family, could spend a few days and nights here on the beach with me, meditating the way I have on the meanings of collapsed dream-homes and lost tent pegs.
Best wishes to all Newsletter subscribers,
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