The value of mud

Mud. Thick, gunky, suck the shoes off your feet mud. A superficially worthless and oft-derided substrate that isn't given nearly the due it deserves. If you like birds, especially shorebirds, mud is worth something. And if you are interested in the big, long-term picture of plant distribution and global ecology, mud takes on a whole new meaning.

Here's a whole lot of mud. I was up at Hoover Reservoir yesterday, which is a large impoundment just north of the city of Columbus, Ohio. Many years, autumnal draw-downs produce acres of mudflats at the upper end of the reservoir, much to the delight of birders. When conditions are as above, Hoover ranks among the best stopover sites in the region for long-haul migrant shorebirds.

At first blush, a big mudflat appears rather two-dimensional: mud, and water. The birder's eye is mostly preoccupied by the above, the interface of water and mud. This is where most of the shorebirds congregate, generally speaking.

But this big, open landscape is full of subtle ecotones, and carefully watching the different species of plovers and sandpipers will reveal distinct affinities for different niches. Yellowlegs, Stilt Sandpipers, dowitchers, godwits and other long-billed, long-legged species typically forage in the shallows just offshore from the mud.

Semipalmated Sandpipers and Dunlin often occur right at the mud/water interface. Least Sandpipers and Semipalmated Plovers will frequently forage a bit further back from the water, where conditions are a bit higher and drier.

We saw over a dozen shorebird species at Hoover yesterday, and as always it was fun and instructive to watch their various methodologies for plundering the mire of its tiny invertebrates.

But four species that were present really pique my interest: American Golden-Plover, Baird's Sandpiper, Buff-breasted Sandpiper, and Pectoral Sandpiper. These are truly global wanderers, nesting in the North American high arctic tundra, about as far north as one can go, and wintering at the other end of the globe, in southern South America.

And all of them share a commonality in habitat preference - they prefer the drier spectrum of the mudflats, where vegetation is starting to reclaim the barren ooze. In the above photo, we are well back from the water, and an elevational rise of just inches has allowed the mud to dry to the point where plants are forming a green carpet.

Experienced birders know to look in the vegetated flats for Buff-breasted Sandpipers, and indeed there are two in the shot above. I have often found the beautiful little Baird's Sandpiper foraging in the proximity of the Buff-B's, and golden-plovers and pectorals often utilize this type of situation. That's why the superficially similar but ecologically barren sod farms can briefly play host to this suite of species.

The innumerable links between birds and botany are not nearly as well studied as they ought to be, and that's especially true with shorebirds. So, we'll move in and dissect the prime Buff-breasted et al upper mudflat habitat.

The Hoover mudflats emerald carpet, that every visiting birder who walks onto the flats traipses through, is dominated by this species: Creeping Lovegrass, Eragrostis hypnoides. A prostrate little annual grass, it is the first plant to begin colonization of the bare mud, and eventually forms coarse meadows covering acres.

A close second fiddle to the grass are sedges, in terms of dominance. Jutting above the rest in this photo is Rusty Umbrella-sedge, Cyperus odoratus, which at perhaps three inches in height is not casting much of a shadow. However, it towers over the Awned Flatsedge, Cyperus squarrosus, which is what nearly everything else in this photo is. And it's the latter that co-dominates with Creeping Lovegrass to form the vast mowed meadow look at Hoover's mudflats, and many other wetlands throughout the Americas.

A handful of dicotyledonous plants makes the scene as well, and this is one of the more obvious: Tooth-cup, Rotala ramosior. Should you find yourself at Hoover looking for shorebirds, take note of all the little Twizzler-like pink shoots jutting from the mud - they're this.

If you've got a sharp enough eye to pick out a Western Sandpiper from the Semipalmated Sandpipers, you should be able to pick out this Sessile-fruited Ammannia, Ammannia robusta, from all of the Tooth-cups.

All of these plants are seed-bankers; species adapted for short-lived, irregularly appearing habitats. Their seeds are capable of decades-long periods of dormancy, entombed in the mud and awaiting the return of conditions favorable to germination and growth.

Tiny and unimportant as these plants may seem, they are actually of extreme importance over the long run. Mudflat seedbankers are frontline ecological pioneers that jump into an unvegetated niche, and begin the all-important process of stabilization. If water levels remain low for long enough, these plants help shore up the substrate enough for bigger, long-lasting plants to invade.

And even if they don't stay long, for the brief period that lovegrasses, sedges, etc. blanket the mudflats, they radically change the animal food supply of the flats. I observed an abundance of tiny insects in the plants, and even numerous jumping spiders, robber flies and other small predators. So, for birds like the Baird's and Buff-breasted Sandpipers, the vegetated upper flats provides a food-rich foraging environment unexploited by the rest of their ilk who remain in the water or fresh mud.

Distribution map of the Buff-breasted Sandpiper, courtesy Cornell Lab of Ornithology. In their global wanderings, migratory sandpipers such as this hit a lot of spots between breeding and wintering grounds. And it stands to reason that over the millenia that these birds have been flying the earth, they've been part of plant migration.

This is the isotype (dupicate sheet of the actual specimen from which a species was described to science) of a plant known as Ammannia latifolia. It is very similar to the species that I shared above from the Hoover mudflats, Ammannia robusta. However, this species was described to science from material collected in... Argentina!

Both the Creeping Lovegrass and the Awned Flatsedge also occur in Argentina and the wintering grounds of the Buff-breasted Sandpiper and its long-haul brethren that winter in South America. There are numerous other botanical examples of this plant-shorebird connection, too.

I think it is likely that shorebirds such as the ones that I've mentioned are the dispersal agents for moving northern plants species to the other end of the globe, or perhaps vice-versa. The odd seed is certainly going to make the trip from time to time, either in the bird's digestive tract or perhaps stuck to its body. Given enough time - and they've had plenty of that - this should lead to isolation and speciation, as could be the case with the Ammannias and others.

Food for thought, and an angle that perhaps sandpipers and plovers are not given credit for although they might deserve it. Certainly very little study, at least that I'm aware of, has gone into the botanical/shorebird connection.

Nodding Rattlesnake-root

Your blogger is dwarfed by a gigantic, 11-foot Nodding Rattlesnake-root, Prenanthes crepidinea.

While on a recent botanical foray in the Cincinnati area, Brian Riley, Dan Boone and I stopped by Fernwood Park. not to admire ferns, but rather to seek this beast of a plant; a species that I had seen in flower only twice prior.

No mystery where the "nodding" in the name comes from - the flowers droop noticeably on arched pedicels.

This species and others in the genus Prenanthes are the so-called "wild lettuces", and exude a milky sap if bruised. Most are rather homely plants, although this one does have a bit of an allure when seen closely. The buttery yellow flowers are rather attractive, although I don't think you'll see the gardening crowd - even native species advocates - clamoring for Nodding Rattlesnake-root any time soon.

For such jumbo plants, the various species of wild lettuces key out on rather minute characters. Prenanthes crepidinea separates from most of its brethren by these pubescent phyllaries - the greenish "cup" that the flower nestles in. You can easily see these whitish hairs in the shot above.

Nodding Rattlesnake-root is essentially a plant of the Midwest, and was once thought to be quite rare in Ohio. And it is, if mature flowering plants are what you seek. The plant occurs primarily on floodplains and stream terraces, and typically never makes it past the stage shown above. Rosette leaves shoot forth in April, last a month or two, turn yellow, wither and die. Once we learned to recognize these young plants for what they are, we began finding Nodding Rattlesnake-root practically everywhere.

But only when some sort of disturbance opens the canopy and exposes the plants to a good jolt of sunlight do they fire from the ground and elevate to Jack-in-the-beanstalk proportions.

Wood Frog

While hiking a remote trail along Little Beaver Creek in Columbiana County last Sunday with Jim Dolan, a Wood Frog suddenly popped from cover and had the good graces to bound onto an emerald moss blanket.

The little frog looked up at me, possibly wondering what kind of bizarre hopless biped had stumbled into its path. I promptly flopped down to its level, and began making some photos. Wood Frogs are quite terrestrial and spend most of their lives in woodlands, away from water. Still, they are tiny and adept at hiding, and one doesn't all that often get confronted by one.

Wood Frogs become most conspicuous in late winter/very early spring, when they migrate en masse to vernal pools to mate and lay eggs. For a few days, woodland pools reverberate with the collective chuckles of the assembled amphibious throngs, which sounds all the world like a pack of distant ducks. Often, the ice still skims the the margins of their breeding ponds, but a bit of chilly water effects the little beasts not one iota.

No amphibian ranges further north than do tiny Wood Frogs. They survive and thrive all the way to the tundra. The black-masked hoppers can freeze nearly solid, and thanks to the production of what is essentially an anti-freeze chemical, they readily thaw back out and are good as new.

While there are plenty of formidable amphibians, such as the devilish Two-toed Amphiumas of the deep south, the miniature Wood Frog gets my vote as toughest amphibian.

A bizarre - and rare! - parasite

To a lot of people, this is one of the more despicable plants: Giant Ragweed, Ambrosia trifida. This jumbo native member of the Sunflower Family, Asteraceae, is the most common source of hay fever, its scratchy little pollen particles tickling the sensibilities of many. An abundant species, Giant Ragweed is not normally something I would search out, but it is central to the strange story that follows.

The mighty Great Miami River, not far upstream of its confluence with the Ohio River. Rivers, especially big Mississippi drainage arteries such as these two, serve as major plant migratory corridors; botanical superhighways, if you will. I love exploring habitats such as the above, which are filled with interesting plants.

When Dan Boone - yes, Daniel Boone - called late last week with news of a major find, I had to go. So, on Saturday I was down in Cincinnati to meet up with Dan, Brian Riley, Marjie Becus, and Stan Lockwood. And up the Great Miami we traipsed, to see the exciting and odd find that Jim Decker and Dan had made just a few days prior.

Along the way to our destination, we encountered many interesting plants. This is a type of arrowhead, the Southern Wapato, Sagittaria montevidensis, a rarity of seasonally exposed mudflats. It trails low over the muck, and has very wide lobed leaves. Like all of its ilk, the three-parted flowers are exceedingly showy.

It goes without saying that nearly all of us were excited to encounter this midget - the aptly named Dwarf Bulrush, Lipocarpha micrantha. The tiny spikelets resemble pineapples, and one must look closely to admire their charms. A robust specimen, such as this one, could fit comfortably on a half-dollar coin. Another rarity, Dwarf Bulrush is known from only a smattering of sites in Ohio.

OK, here we are - our destination. Daniel Boone poses in front of an enormous thicket of Giant Ragweed, towering to 15 feet in height. I cannot think of a more shunned habitat than this. Ragweed is quite common on riverine bottomlands, and forms impenetrable jungles largely devoid of other plants. Couple the non-diversity factor with the allergy issues with the accessibility problems, and you've got a situation avoided by all.

Except for some botanists in Indiana, who not long ago discovered a mega-rarity that associates with ragweed, and showed it to Dan. So, he and Jim Decker went looking in Ohio, and Voila!

Now this is a very cool plant: River Broomrape, Orobanche riparia, shooting up between two massive ragweed stalks. There were only two prior Ohio records, both quite old, and back when the plant was considered Orobanche ludoviciana. Recent work has shown that the broomrapes in the O. ludoviciana complex that occur along floodplains differ morphologically and are indeed a different species.

You can see how this botanical oddity could easily be missed. Not only is no one looking for stuff in this habitat, but the ragweed absolutely overpowers the comparatively delicate broomrape, and renders it somewhat invisible.

Upon close inspection, the plant reveals itself to be quite showy. Densely beset with purple and white flowers, and utterly lacking in leaves, this is one distinctive plant.

Here, we've brushed away the soil to reveal the odd relationship between the broomrape and its host, the ragweed. By the way, the origin of the rather unpalatable common name is derived from the Latin rapum, which essentially means "knob", and refers to lumps caused by Orobanche infestation on a species of pea.

River Broomrape, like the rest of the 200+ species of Orobanche, has little to no chlorophyll, and must attach to a suitable host via specialized root structures known as haustoria. It then extracts all of its essential nutrients from the host plant. The large root extending up from the bottom left of the photo belongs to the ragweed. The thick, fleshy yellow stems on the right are the subterranean portions of the broomrape.

In tight on the basal, or lowermost section of the broomrape root. This is the business end; the part that attaches itself to the ragweed and sucks out the goodies.

Seen well from a belly-flopped perspective, the River Broomrape is quite a looker. The flowers are a bit orchidlike, and the entire assemblage is densely beset with glandular pubescence, lending a sticky look to the plant.

It wasn't long before Marjie Becus spotted another broomrape, and in all we found a dozen or so new plants. I suspect that there are plenty more lurking out there. Should you find yourself of a mind, start crashing through thickets of Giant Ragweed along the banks of the Ohio River or the lowermost sections of its major tributaries. You just might unearth some more populations of this very cool plant.

Kudos to Dan and Jim for tracking down River Broomrape, without doubt one of the best botanical finds of 2010.

Snowy hummingbird

Tim Tolford, who is one of a small handful of people that is licensed to band hummingbirds in this neck of the woods, sent along some shots of a real eye-catcher. The hummer shown below is quite the oddity, and turned up in recently in St. Louisville, Ohio.

This is a leucistic female Ruby-throated Hummingbird, and it is cool! One can only imagine the hubbub and speculation if this thing winged by a bunch of birders.

Leucism - loo-kis-ism - is a genetic abnormality that causes color pigments to become washed out and pale, creating a bleached look. Albinism, which causes a similar look, is caused by melanin production becoming greatly reduced or curtailed, and pure albinos have pinkish eyes among other differences. Also, a pure albino wild bird is not likely to fare well or last long, due to the resultant weakening of hard structures such as feather shafts.

Although a strongly leucistic animal such as this hummingbird doesn't suffer the structural disadvantages of an albino, at least to as great a degree, I still wouldn't lay odds on the longterm prospects of our snowbird. For one, it is probably much more detectable to predators, especially when in a semi-torpor at night. And I would also wonder about its ability to attract a mate, but who knows, maybe the hummer-dudes will think she is cooler than the average bird.

Anyway, Tim reports that the snowy hummer seemed to be doing just fine, although it was seemingly the target of excessive aggression from its "normal" compadres.

You can read more details about this interesting bird HERE.

Thanks to Tim for sharing his photos, and for all his avian research work.

Hickory Horned Devil

I promise to lay low on the caterpillar/moth/butterfly stuff for a while, but the following pics and story is just too cool not to share.

Thanks to David Hughes and Laura Stalder for discovering this amazing creature, taking pains to help ensure its survival, and sharing their photos with us.

The incredible Hickory Horned Devil, probably the most spectacular caterpillar in the eastern United States. These things are mammoth; the size of a hotdog. While they look fearsome and dangerous, Hickory Horned Devils are all bark and no bite. Those intimidating horns don't inject poison, the thing can't bite, and if you can overcome the fear factor, they're easy and safe to handle.

Hickory Horned Devils spend their time high in trees, vaccuuming up foliage like an over-active paper shredder. Thus, they're hard to spot, and I've only seen one. I was with a moth expert, and he actually spotted the devil's frass, or droppings, on the ground and then looked up and saw the cat up in the tree.

While David and Laura watched the devil happily chowing on walnut leaves, other creatures with much more malicious intent were also watching. Here, a tachinid fly moves in to investigate the caterpillar. There are scores of species of tachinids, and some look much like house flies, as this one does. But they've all got long stiff bristles, on their abdomen, which give them a distinctive appearance.

If you are a caterpillar, you don't want to be stalked by one of these flies. Even though the horned devil outmasses this little fly by a factor of 100 or more, the tiny tachinid spells doom. If you want to see the ultimate result of a tachinid's handiwork, GO HERE.

As David and Laura watched, the tachinid fly extended a long ovipositor (an appendage for laying eggs) and began sticking small, gluey eggs to the Hickory Horned Devil. Her spawn is visible in the above photo: six little white dots. Left to their own devices, those eggs would quickly hatch and the miniscule fly larvae would promptly burrow into the caterpillar's tissue. Once inside, they would commence eating it alive, cleverly avoiding the most vital of tissues, thus keeping their victim alive for as long as possible. Eventually, like a scene from a sci-fi horror flick, the now much larger fly grubs would burst from the body, leaving behind little more than a hollowed out husk.

This is the world's luckiest Hickory Horned Devil. Dave and Laura knew what was going on, and fetched a pair of tweezers. With the precision of a skilled surgeon, they carefully plucked the eggs of death from the devil's body, and hopefully it'll survive to pupate and become one of our flashiest moths.

Hickory Horned Devils grow up to become one of these, a Royal Walnut Moth, Citheronia regalis. I took this shot a few years back at the amazing McMoth's in West Jefferson, Ohio. Royal Walnut Moths are just about as impressive as their caterpillar - massive hand-sized things with a furry body the size of a roll of nickels.

Thanks to David and Laura, not only for sharing their amazing photos with us, but also for their caterpillar rescue operation that will hopefully result in another much-needed Royal Walnut Moth.

Carolina Sphinx

Big, lime-green and boldly patterned, the curious-looking Tobacco Hornworm is the bane of many a gardener. If the parasitoid braconid wasps don't get them, irate tomato-growers often do.

I suspect a lot of people who bump off Tobacco Hornworms don't know what Stage II is. The caterpillars, if they make it, eventually become beautiful Carolina Sphinx moths, Manduca sexta. This one was resting on a brick wall on the front of the building where my office is, in a very urban part of Columbus, a few weeks back.

Last night, I was up to visit my parents in Worthington, and stepped into their backyard to see what insects might be singing. Their yard, at least the back yard, is a fabulous suburban habitat full of a wonderful blend of native plants and ornamentals. I always find interesting things there.

Anyway, right outside the back door is a lush patch of Four-o-clock, Mirabilis jalapa. This non-native ornamental closes its flowers during the day, but they come into full bloom after nightfall - a design for attracting pollinating moths. And I hadn't even got out the door when I saw an enormous moth working the plants.

A Carolina Sphinx! These moths really are cool when on the wing, looking all the world like a big, sluggish hummingbird. Nearly the size of a small bat, they are conspicuous when noticed, but as they ply their trade in complete darkness, Carolina Sphinx moths often go unnoticed.

This is a moth totally adapted for working flowers with extremely long corolla tubes, such as various phlox, and these Four-o-clocks. Look closely and you'll see its tongue extending deep into the flower.

When actively foraging for nectar, Carolina Sphinx moths tend to keep their ridicuously long tongue unfurled and ready for action. It's well over the length of their body. Gene Simmons has nothing on these guys!

To make the moth's incredible tongue easier to see, I highlighted it in white. Amazing!

Think about the other part of the caterpillar's life cycle the next time you go to snuff out one of the offending Tobacco Hornworms, and should you have any Four-o-clocks in the yard, go have a look at them after dark and see who is visiting.