|Previous Nature Walks|
|Lizards are waking up in winter!|
|Lizards, like all reptiles are cold-blooded and are not active when the temperature drops below a certain point. Here in north central Florida, however, we often get temperatures in the high 70s F in winter. This year, perhaps because of the global warming trend, January and February have seen highs in the 80s F and the lizards love it!|
|How do robins and birds in general navigate? This is an area of bird biology that has been studied by many scientists over the years and various theories have been proposed. The current opinion seems to be that there is not one but several types of cues that a bird uses to tell direction. These may include star patterns, the direction of the setting sun, the earth's magnetic field or the direction of the prevailing wind. Migration seems to be programmed in the genes of migratory birds, but they are also able to learn geographical landmarks and can return to the same area year after year.|
There are many other questions about migration that have not been answered completely. What tells a bird when it is time to begin flying south in the winter and then later when it is time to head back up north to the breeding ground? How does a migrating bird know when to stop? What effect will global warming have on bird migration? These are all intriguing and important questions that you as potential biologists can choose to study.
Humans move around a lot, although we cannot be said to actually migrate. Herders may move seasonally so that their flocks can have better grazing. Nomads move when food supplies dwindle. In Florida we have the 'snow-birds', flocks of northerners from Canada, Michigan, Maine and other cold-winter states who migrate south in October or November and then return home in March or April. I don't think it is genetic, however, and they tend to navigate by road signs and GPS rather than by the stars.
These flowers are commonly known as turtleheads or dragonheads, because of an imagined resemblance of the flower to the heads of those creatures. Their scientific name is Physostegia virginiana and they are in the mint family, Labiatae. Physostegia is also known as obedient plant because if you bend the flowers in a new direction on the stalk, they will remain that way.
The white disk with the darker scales is the cap of a mushroom known as the parasol, Macrolepiota procera. It is edible and quite tasty when fried in butter and served up on toast with ham and eggs. The orange flowers in the photo are marigolds.
|Hernando County Florida Christmas Bird Count - 2007|
|Saturday December 15 was the annual Audubon Society Christmas bird count in our area. For those of you who may not know what this is, every December, all over the United States, members of local Audubon birding societies meet early in the morning (usually 5:30 am!) and spend the rest of the day traveling a specific route identifying and counting all the birds they see. This bird census has been going on since 1905 and the accumulated data have become of vast importance in monitoring the health of bird species and determining where changes in environmental policy may be needed to protect declining species.|
The Christmas bird counts are an annual tradition in the birding world and we all look forward to the event, hoping for good weather and lots of species. My part of Florida, where we take the bird census, is mostly mixed pine and hardwood forest areas with some ponds. The census area also borders the Withlacoochee River, so we also usually see lots of waterbirds.
Experienced birders can identify many species simply by their calls and this is counted on the census. Visual identification is not necessary. We commonly carry 8-10 power binoculars but also have a spotting scope mounted on a tripod for long-distance viewing at a magnification of 20-60 times. The spotting scope is especially useful for identifying wading birds, ducks, coots, etc. on a large lake.
We met at 6 am and headed out onto a dirt road into state forest area. Our destination was a spot where woodcocks have been seen in past years. These birds are very secretive and rarely seen, so we were not surprised when our patient waiting was not rewarded. However, we did record a number of catbirds, killdeers, barred owls and passerines.
Next we drove to a preserve for the red-cockaded woodpecker (Picoides borealis) where nest trees have been created by the Florida Audubon Society in cooperation with the Florida Wildlife Service. These rare woodpeckers only nest in live trees and it can take a long time for suitable trees to be found and the cavities excavated by the birds. Bird populations have been locally increased by creating artificial nest holes by cutting into mature pine trees (at least 15 inches in diameter at the cavity site) and closing up the cavity after carefully inserting a length of PVC pipe of the correct diameter. This does not usually weaken the tree. The loss of mature pine forest habitat has put these birds on the endangered species list. They prefer stands of pines for roosting and nesting, and controlled burning to eliminate hardwoods (e.g., turkey oak) is necessary to maintain a climax pine forest.
We arrived at the woodpecker site at about 7:15--just around dawn, and set up the spotting scope on one of the nest/roost holes. The photo gives you an idea what the area, which is about 20 acres, looks like. It is a typical Florida scrub with turkey oak understory and some xeric shrubs (Adam's needle, saw palmetto and Florida rosemary). These dry sandy areas are the remnants of the great dunes that covered the central Florida ridge several million years ago when the ocean level was several feet higher than it is now. Natural forest fires maintained the pine scrub until man began controlling the burns and cutting down the forests to plant oranges. Now it is necessary to do periodic controlled burns in order to preserve the scrub habitat.
| From the red-cockaded woodpecker site we walked through the pine woods for about half an hour recording warblers, sparrows, woodpeckers, hawks and other birds. There are many dead trees here that are favored nest sites of pileated and red-bellied woodpeckers and we heard several of these.|
Ovenbird Yellow-bellied sapsucker Female cardinal Male cardinal
Titmouse Phoebe Yellow-rumped warbler Red-shouldered hawk
From the scrub habitat we next went to a cypress pond. Because of the lack of rain this summer, however, there was very little water and no wading birds. We saw cardinals, house wrens, ruby-crowned kinglets, a white-eyed vireo and, of course, the ubiquitous turkey vultures soaring overhead and migratory robins passing by. The house wrens were not seen well enough for a visual id, but we could be fairly certain of them because their calls are distinct from those of the more abundant Carolina wren. The kinglets are tiny chubby birds that have a characteristic white eye ring that makes them easy to id as they flit about in the tree canopies.
These small pond cypress ponds are fairly common in our area and provide a break in the otherwise dry scrub/savannah environments. Pond cypress trees look similar to bald cypress but do not have as many knees and are more common around stagnant water.
|Our next stop on the bird count was a grassy savannah habitat bordered by pines and scrub live oak. This is usually a good locale for sparrows. It is also prime real estate for our Florida gopher tortoises because there is an abundance of their favorite food, prickly-pear cactus, and few predators. We didn't see any tortoises, but there were many active burrows. The tortoise is still on the endangered species list because of habitat destruction, but here at least they are flourishing.|
|The rest of our survey took us to an abandoned dairy farm, an Audubon preserve and a park bordering the Withlacoochee river. We tallied many more species including a northern harrier, many ibises, both white and glossy, collared doves, kestrels, boat-tailed grackles, snowy egret, kingfishers, anhingas, coots, gallinules and grebes.|
If you would like to get outdoors and see wild creatures in their own homes then come and join us on next year's Christmas bird count. You don't have to be a seasoned birder to join the fun. Most of the species we tally are fairly common and easy to recognize by sight or by calls. You can learn quickly by paying attention to how the experienced birders pick out the various species, and soon you will be adding your finds to the list. Plus you often get to explore habitats that are off limits to most people, and you may see some unusual plants, mushrooms and animals other than birds.
All in all, the Christmas bird count in Florida is a great way to spend a Saturday. Lots of good walking, neat things to see, and you have the satisfaction of knowing that you are contributing to a 100 year-old bird census that is a valuable database for ecologists and ornithologists. See you next year!
|October 31, 2007 - This insect is a type of click beetle called an eyed elator.|
Click beetles are named for their unique defensive strategy. If a predator (or curious naturalist!) goes after them, they escape by explosively snapping their carapace. This ultra-rapid motion flips the beetle a couple of feet away and usually so startles the would-be attacker that the beetle is able to scurry away unharmed. I know it certainly surprised me the first time I touched one. With a loud SNAP!, it catapulted itself into the air and landed two feet away.
The eyes are a defense also. They are much larger than the real eyes which are just visible at the base of the antennae. Presumably most predators will be fooled by the 'eyes' into thinking the beetle is not a beetle, but rather some creature such as a snake that might like them for dinner! The stratagem probably does not work all the time, but often enough to ensure the survival of the marvelous eyed elator.
|August 1, 2007 - Living on an island in the Gulf of Mexico is a great way to enjoy the beach.|
The beach is one of my favorite places and I'd like to show you some of the photos I took on vacation over the 4th of July. I stayed a week on a barrier island in the Gulf of Mexico just a short distance off the coast. These islands are not of volcanic origin like Martinique and Trinidad or coral islands like the Bahamas. They are called barrier islands because they protect the coastline from storms and hurricanes. You can find barrier islands all over the world but especially along the east coast of the U.S. where they extend from Maine all the way down to Florida and around to the Gulf of Mexico. Barrier islands parallel the coast and are relatively close to it. Their origin is not known with certainty. One theory has it that when the last ice age ended about 20,000 years ago, the sea levels rose and advanced onto the shore creating bays between areas of higher ground or dunes. The barrier islands often form chains separated by tidal inlets. The separation from the mainland has created some unique and protected habitats, although much has been destroyed by over-development. The island I stayed on does not allow vehicles except golf carts and so far has restricted the building of condos and hotels. Sea turtles still dig nests in the sand to lay their eggs and there are many species of birds, fish, crabs and reptiles that call the island home.
I walked from one end of the island to the other in a couple of hours and its width is only a mile or so. On the bay side opposite the mainland you will find mangrove tangles and calm water, but no beach to speak of. On the Gulf side there are dunes and areas of scrubby vegetation that can withstand the heat, dryness and salt. The plants with the greatest salt tolerance can be found closest to the water while those less resistant form a gradient further and further away. In the picture you can see the way the habitat looks with low-growing cabbage palms, pigeonplum, beach rosemary and sand live oak. Prickly pear cactuses grow well here and are the favorite food of gopher tortoises. I saw the tortoises every day and some were quite large. There were also a number of rabbits browsing the sparse vegetation.
The dunes closest to the high-water line are held together by the roots of a number of plants. Sea oats, Uniola paniculata, is one of the best known of dune grasses because of its pretty sprays of oat-like seeds. You might be tempted to pick these for dried-flower arrangements, but donï¿½t do it. The plants and the dune ecosystem are protected because they are so fragile. I used to climb on the dunes as a kid before I knew better, but now I wouldn't think of it. |
The pretty pink flowers belong to the aptly named railroad vine (Ipomoea pes-caprae), another dune stabilization plant with deep and extensive roots. It gets its name from its long runners that may stretch across the sand for 30 feet or more. It amazes me that this plant can flourish in sand so hot it burns my feet and so dry that there seems to be no moisture at all. It is a mystery how the seedlings get started. They must grow very quickly after a rain and put down very aggressive roots.|
Ghost crab (Ocypode quadata) holes are everywhere on the beach. I love these critters. Our high school football team was called the Sandcrabs which is another name for them. They usually emerge from their holes around dusk, and I would follow their tracks until I found them. They hunt around in the seaweed that piles up along the tide line and eat whatever tasty bits of animal and vegetable that have washed up. They are very fast and can easily outrun you, at least for short stretches. They will make for their own burrow if possible, but if they are too far away they will rapidly dig down into the sand until just their long eye stalks are visible. I have seen some old ones with shells 8 cm across and formidable claws.|
One sign of a healthy beach habitat is the presence of sea turtle nests. This island has a lot of them. In fact there is one person who has made it her job to patrol the beach every morning to look for the turtle tracks from the night before. When she finds them she puts up a rope around the nest site with a sign telling people not to walk on or disturb the area. I found the tracks in the picture one morning early before she did. One night when there was enough of a moon to see by, I walked on the beach looking for the mothers-to-be. Eventually I did see one and watched very quietly as she slowly and with great effort pulled herself up onto the sand near the dune line, dug a 2 foot-deep hole with her flippers then deposited a large number of eggs (sometimes more than 100) in it. She carefully scraped sand back into the hole until the eggs were well covered, then made her way back to the water, her duty as a mother completed. The eggs will hatch in about 2 months depending on the temperature, and the baby turtles will make for the brightest area which usually is the surf, but people with houses on the water are asked to not turn on bright lights during turtle nesting season because sometimes the hatchlings are confused by house lights and head away from the water and die. The turtles are a point of pride with the islanders and they guard the nest sites and hatchlings very diligently. As it is, only a few of the baby turtles will survive predation by birds, raccoons, and fish to grow up to be adult green or loggerhead turtles and repeat the cycle of egg laying.|
The sun is setting and we gather every evening to give thanks for the beautiful day and the marvelous world that contains so much of beauty and fascination for the person who stops to look.
|May 7, 2007 - Bugs beware, when geckos are on the prowl!
Forget about what you've seen on the Geico ads! Geckos are single-minded predators with an insatiable taste for insects and spiders. Our geckos are pretty smart. They hang out near the porch light and snap up the moths that are attracted to the light. Easy pickins! The moths practically fly into their mouths.
The gecko with the spider had ventured inside the laundry room downstairs and found himself without the usual supply of moths. So he searched around the walls and ceiling until he found the rather large spider you see in the picture. Notice that he attacked from the rear away from the poison fangs which certainly could have done him some harm if the spider had been able to inject its venom. In fact, our pet spider Emily caught a small gecko once in her web and killed and ate it. This spider, however, was not so lucky.
These geckos go by the name of common house geckos for the obvious reason that they live in and around human dwellings. They are quite attractive with their large glittering eyes and sand-colored skin, and they can be very useful in eliminating undesirable bugs from the home. They are not pets and catching them is nearly impossible. In Bali, Indonesia, they are called 'chichaks' because of the sound they make in calling to one another. I have never heard our geckos calling but maybe they are more shy. They take over the night shift from the more aggressive swifts and anoles who cruise around the deck and fence all day long looking for daytime bugs. Come to think of it, a bug's life is pretty risky around here what with all the reptiles, birds and other predatory insects on the prowl. Humans have a lot of problems in life, but at least they don't have to worry about being snapped up by giant lizards at every turn!
|Camouflage Adaptation Protects Tasty Moth|
|May 6, 2007 - To avoid being eaten, don't look like dinner!.
This morning early I opened the door to see what was going on outside and noticed a leaf shape on the wall under the porch light. I went outside and saw that it was a brown moth looking exactly like a dead leaf in shape and color, even down to the black splotches that one sees on a real dead leaf. This was one smart moth. Actually not so smart because this is a favorite hunting ground for the wrens and cardinals who come every morning to snap up moths that have spent the night on the wall after flying around the porch light.
The birds did come as usual, but my leaf-moth fooled them. They did not even seem to notice it although they eagerly grabbed other moths on the door and wall that looked like moths. They fly down to the porch with their breakfast and break off the wings before gulping down the fat body. Not very pleasant for the moth, but that's the nature of Nature. We're predators too, except that we rarely kill the animals we eat. If you are tasty and small, you had better try to look like something else. Insects actually are very good at camouflage, especially moths which are both small and tasty. Other insects have bright colors that warn potential predators that they contain poisonous or bad tasting compounds. Others are masters of mimicry and have morphed into wasp or bee look-alikes. Most predators don't go after prey that has a stinger!
Our pet spider, Emily, can tell a good moth from a bad moth. Not all moths are good to eat. Some have developed a really neat chemical defense. They eat a plant that contains a toxic alkaloid called pyrolizidine and incorporate the chemical into their wing scales. Apparently they can eat the toxin and not be harmed by it, but woe to the critter that tries to eat them! Emily has learned to avoid this kind of moth, and if I try to feed her one, she simply cuts it out of her web and drops it on the floor in disgust. Then I have to go and find one of the tasty brown kind that she likes to make amends for giving her a bad one. She has me trained well and I am very glad to be a human and not a moth!
|Jan. 14, 2007 - Miniature ants read my sciblog while I'm working outside.
Yesterday I was sitting at the picnic table, my outdoor office, on the patio working on a sciblog and enjoying the warm Florida winter. My eye was caught by some movement on the surface of the table. It was an insect so tiny that I could not even tell what it was.
I got a magnifying lens and took a closer look. Now I could see the characteristic three-part body of an ant although much smaller than any I have ever seen--probably less than a millimeter. I ran into the house and grabbed the camera. There were now three ants on the table, all moving frenetically and impossible to photograph. I kept watching them and eventually one climbed up on my notebook and stopped as if reading what I had just written. Then I was able to get focused and shoot before it took off again.
As you can see from the photos, the ants have a dark brown head and a straw-colored thorax and abdomen. There is a darker, brownish spot on the abdomen and also on the thorax. The antennae are very long--as long
|as the legs--and very mobile. They constantly tap the surface with their antennae as they move around, sampling the surface molecules for food or ant pheromones I guess. They also twitch their abdomens up and down, but I have no idea why.|
These ants seem to be very fast for their size. I estimated that they can move at about one centimeter per second or about 12 times their length in one second. If I tried to do that I'd burn out my sneakers, 'cause I'd have to be moving at 70 feet per second! I put some bread crumbs from my sandwich on the table to see if they might be hungry and sure enough one ant grabbed a crumb that was bigger than itself and scurried away. The photo shows the movement.
Florida has a wonderful population of bugs! Most people don't think of them as anything but a nuisance, but I find them fascinating, colorful and amazingly adaptable critters. In Aesop's fable of the ant and the grasshopper, the ant is portrayed as the industrious one who puts away food against the coming winter while the grasshopper fiddles and dances--then later starves. Bugs have lots of other interesting stories to tell if you take the time to watch them and learn something about their lives. If you have a digital camera with a close-up lens, you can take lots of neat photos and eventually build up a collection of pictures of live insects--much better than the old butterfly boxes with the desiccated bodies pierced by pins. Check the web. There are thousands of sites on insect life in all parts of the world. One of my favorites is BugGuide which has a simple-to-use key for identifying insects, spiders and their kin, and lots of pictures that you can use for comparison with your photos. So go out and get bugging! I think you'll have fun and you may see something that no one else has photographed before.
|Oct. 22, 2006 - Mysterious fuzzy balls litter the ground!|
I noticed these fuzzy tan balls on the ground under a tree near my house and picked one up to see what it was. It was about a centimeter in diameter, quite light in weight and soft. I counted 30 of them on the ground in an area about five feet square and looked up to see where they might have fallen from. There’s a young live oak whose canopy overhangs the area and I thought I could see some of the ‘fuzzballs’ on the leaves. I got the 20 foot extension ladder, leaned it against the trunk of the oak and went up to have a look.
Sure enough there were a half dozen or so of the little tan spheres attached to leaves by a short stalk. Each leaf that had one also had a brown dead spot at the point of attachment. I cut off a branch and carried it down to the ground to examine. The balls were securely attached, usually to the lower surface of the leaf, but sometimes to the upper, by a short projection of the leaf itself. Some of the leaves had the remains of stalks where the balls must have dropped off onto the ground below the tree for me to find.
I took one of the fuzzballs into the lab and pulled away the ‘hair’ with forceps. Within was a small greenish body about 4 mm across. It looked like a small berry—definitely not an insect or cocoon. With a scalpel, I cut the fruit in half and examined it under the dissecting scope. I could see a bump on one end, probably where the stalk had been, and in the center was a small body that I could not see well enough to determine what it was. I took a picture and you can see that the object in the center does not show up very well. I also examined some of the hair under the microscope and it looks remarkably like wool fibers, flattened and a little twisted.
So, what are these fuzzballs? I did a Google Image search for ‘fuzzy’ and I found them. They are called wooly oak galls and they are produced by a gall wasp which lays its eggs on oak leaves. When the egg hatches, the larva begins to eat the leaf and some chemicals in its saliva cause the cells of the leaf to divide and form a spherical home for the larva while it is metamorphosing into a wasp. Many of the galls are smooth on the outside, but this type somehow induces the oak leaf to cover the gall with a thick wooly coating of ‘hair’. If you know something about how cells work, you know this is pretty amazing stuff. The gall larva is producing specific chemicals that act on the oak leaf’s cells to divide. But not only to divide! The signals tell the leaf to form a spherical body of a certain size and shape covered in wooly hair! If we knew how that was done we might be able to take a snippet of heart tissue and treat it with specific chemicals that would cause it to grow into a new heart, or likewise with a kidney or liver for transplantation. We have learned a lot about biology, but there’s sure a lot more we don’t know!
|Oct. 15, 2006 - Nightmare predator in your backyard!
Have you ever seen these funnel-shaped holes in the sand and wondered how they got there? I grew up in Florida which is basically one long sand dune, so I saw these mini-craters frequently. Did you know that these holes are made by an insect? There is an insect called an ant lion and the larva of the ant lion makes the holes as a trap for other insects. When an ant or other small insect tumbles down the steep sides of the hole, the ant lion larva is waiting at the bottom to welcome it with open jaws!
Ant lions belong to that category of insect that undergoes a metamorphosis (‘change in form’) from a larva (‘grub’) to a completely different adult form. The Monarch caterpillar forming a beautiful green chrysalis and emerging some time later as a spectacular butterfly is a good example of insect metamorphosis. The creature that lives at the bottom of the sandpit and catches ants is the larval form of an adult with long lacy wings something like a dragonfly’s only folded back along the abdomen. The adult antlion-fly is seldom seen and it feasts on plants, not ants. So, why does the antlion go to all the trouble of changing itself into a winged form when it can live perfectly well in the sand? Think about plants and their seeds for a minute. Many seeds, like those of the dandelion for example, have little parachutes that waft them up on the slightest breeze and can carry them a mile away. The reason plants go to all this trouble is the same reason insects have an adult form that can fly--to ensure that they are spread over a wider territory. If all the ant lion could do was walk on the ground, the area would soon be ankle deep in ant lions and they would starve!
|Sept. 17, 2006 - Mushrooms are popping up everywhere!|
Here in central Florida we have been having downpours of rain nearly every day and the mushrooms are popping up in abundance. Everywhere I walk in the garden and the yard I see amanitas, boletes, armilleria, cortinarius, lactarius, russulas and many others I haven’t identified.
The various types of cap and stem and gills or pores, white or tawny or red, are all part of the fungal ‘fruit’, the part that carries the spores which are transported by the wind to make new fungi. The part that you don’t see is actually the main body of the fungus—a white stringy network of root-like threads called the mycelium.
Fungi, as you should know, are not plants. They lack chlorophyll which is the defining character for admission to the plant kingdom and many of their genes differ markedly from those of plants. Fungi may be parasites on plants or animals but more frequently they are saprophytes, decomposing organic matter and living on the recycled nutrients. They are an essential part of the ecology and one
|that is underappreciated because their contribution is invisible. Many trees have an intimate relationship with fungi. The mycelium entwines with the tree’s roots and shares the sugars made by photosynthesis in the tree’s leaves. In return, the fungus delivers to the tree a variety of nutrients that it absorbs from the organic matter in the soil. The system is a beautiful example of balance, recycling and mutual benefit that humans would do well to consider.|
Here are some snapshots of my fungal neighbours taken with an Olympus C7000 digicam. The spore print was made by carefully slicing through the stem of the mushroom where it joins the cap with an Xacto knife, then placing the cap gill-side down onto a piece of black paper and covering it with a bowl. To collect spores for microscopic examination, I put a glass slide on the paper and laid the cap on top of it.|
The spores which are white and elliptical were examined and photographed under 40X and 400X magnifications using the same camera. There are some diagnostic chemical tests that one can do on the spores to help identify the species, but I haven’t done them yet. Also, the length and diameter of the spores can be measured with a micrometer eyepiece on the microscope and these spores averaged 9.5 microns long by 6.5 microns wide. I think it is Amanita bisporigera because under the microscope one can see that the spores are carried on the basidia in pairs.
Sept. 2, 2006 - Aliens masquerading as plants?
As I was taking my coffee in the garden early this morning, the hairs on the back of my neck began to prickle and I had the uneasy feeling that someone or something was watching me. I slowly looked around not knowing what to expect--an inquisitive squirrel? a stealthy cat?
Neither, as it turned out. Behind me growing around and upon the big hickory next to the house is a large clump of bromeliads that blooms every year about this time. The pineapple is an edible bromeliad, but others are grown for their large, colorful flowers.
This particular bromeliad, however, had two flowers separated by a long leaf protruding out from what seemed to be a face. As I looked at the flower 'eyes' there seemed to be a movement of the air around them like the convection ripples that you see from a hot object. At the same time the leaf turned slightly from side to side as if it were an antenna trying to tune in some signal. I watched the 'plant', fascinated, for a moment then walked towards it to get a closer look. The rippling around the flowers stopped and the leaf became still.
I examined the plant closely. It appeared to be no different from the other bromeliads on the tree and did not respond to my touch. The thought crossed my mind that I should pull it up and burn it, and at that instant I seemed to perceive the rippling of the eyes again, but it was so quick I could not be sure. I decided to leave it where it was, so i got the camera and made the picture that you see.
|I do not really think that my bromeliads have been taken over by sentient beings from some other world, although the idea is not as crazy as it sounds. Any life form capable of interstellar travel, whether by hyperdrive space ships or controlled wormholes or parallel universes, could certainly have powers way beyond our current comprehension. Just imagine taking a man from, say, Babylon of 4000 years ago and showing him around one of our modern cities. Very little that he saw would make sense to him in his context because he has no referents for it. His mind would construct a picture of our world very different from what we see. The same would be true of us faced with alien technology with the added problem that the aliens would no doubt be very different from us physically.|
The hypothetical 'Grays' who many believe have visited Earth already, look humanoid, but that certainly does not mean that all intelligent life has to resemble us. In fact, they may not even have a physical body at all. This would simplify space travel. A coherent energy packet could contain all the information that we carry around in our neural circuits and be theoretically transmissible through subspace. The waveforms would simply take over another organism's body in order to interact with the environment in a physical way. The chosen body could be anything, from humans to plants.
Of course, this is in the realm of scifi right now, but think about all the inventions scifi writers have come up with that now are commonplace--portable wireless communication devices, supercomputers, robots, space travel, orbiting laboratories, laser 'death rays'--even faster-than-light travel and teleportation. No one can say with certainty what an alien technology might or might not be capable of or what form an alien creature might take. I keep an open mind, but I'm certainly going to also keep a watchful eye on that bromeliad!
|Aug. 20, 2006 - Gecko toes, the ultimate adhesive!|
Geckos are pretty amazing creatures and not just because they can sell auto insurance with a British accent. They resemble a flattened version of a lizard and like a low-slung Ferrari, they can accelerate and turn incredibly fast. But unlike the auto, the gecko can go up a smooth wall and across the ceiling with ease. In fact, I hardly ever see them on a horizontal surface. How can they do this? The secret of their traction lies in the high-tech structure of their toes.
Look at the close-up photo of the gecko’s hind foot. I took this picture of a large (about 12 cm)gecko that had gotten into the kitchen somehow. I first saw it on the window and snapped the close-up picture as it stopped on the window sill. Afterwords I openend the window and it jumped out. Each toe has a pad on the underside which is made up of a series of ridges. The important part is invisible, however. In fact, you would need a powerful electron microscope to see the nanoscale fibers that cover the surface of the pads. I first read about gecko toes in a 2002 article in the prestigious Proceedings of the National Academy of Sciences (abbreviated PNAS).
|In this report, Kellar Autumn, Robert Full and a number of other scientists from Lewis and Clark College in Oregon and the University of California did some experiments on Tokay geckos (Gekko gecko) to determine just how their sticky toes worked. Some other researchers had proposed a sort of capillary suction effect, but Autumn and Full found no evidence for it. Instead they deduced that the adhesive force is actually a molecular attraction between the tiny fibers (called setae) in the gecko’s toe pad and the surface.|
The attractive force is generated by a large number of induced positive-negative molecular interactions called van der Waals forces which are very weak individually, but together can provide a significant pull. There are a very large number of setae on each toe pad and these are able to exert a van der Waals pull on even the smoothest surface as the researchers found out when they watched their gecko effortlessly walk up a wafer of gallium arsenide, a totally smooth material used in manufacturing semiconductors.
What is just as amazing is that dirt does not stick to the setae. An experiment was done in which a nanoscale powder was dusted onto the gecko's toes and he was then put on a glass surface. At first he almost fell off but quickly the powder was shed from the toe fibers until he was again walking as easily as before. The setae are able to attach to the surface but reject the dirt.
Engineers are open-mouthed with amazement when they see what gecko pads can do and the wheels start turning as they try to figure out ways to duplicate the geckos organic toe structures using manufactured materials. Maybe someday we will have special gloves and shoes we can put on that allow us to safely climb down the side of a building to escape a fire or give recreational climbing a whole new twist.
|Aug. 19, 2006 - Squirrel attack!
Yesterday afternoon, I was sitting at my writing table in front of the sliding glass door that opens out onto the deck when I heard a noise. Something had fallen from the oak tree above and hit the deck. I looked around on the deck but didn’t see anything. Must have hit and bounced off, I thought. I continued working only to be interrupted a few minutes later by the sound of another something hitting the deck. It bounced again but this time I saw it—it was a green pod from the trumpet creeper, Campsis radicans, that twines all around the live oak that arches over the deck.
The vine, which actually is as thick as an anaconda and three times as long, has bright red-orange flowers in May shaped like the loudspeaker on an old Edison Victrola. I was puzzled, though, because the fallen pod was obviously not ripe. It was still green. As I was pondering this mystery, yet another pod came rocketing down from above. OK, I thought. That does it. I’m going out there and find out what is making those pods fall. Grabbing the binoculars, I had a suspicion of what I would see. Sure enough, way up among the creeper vine was a tree rat, aka squirrel, pawing around among the pods. As I wondered whether squirrels eat creeper pods I felt a sharp sting on my arm as another pod came whizzing down. There was a pair of squirrels! And they were about to attack me for all the imprecations and threats of squirrel stew I had heaped upon them over the years!
|I quickly retreated back into the house, grabbed my hat and camera and crept out again, this time going downstairs and around the back under protection of the eaves. I trained the binoculars on the vines but the squirrels must have left, chuckling no doubt about how they had driven me away. I saw more pods on the ground and examined them. Some were bitten into at one end and some had split open, probably from the fall, but others were not chewed at all. Do squirrels eat trumpet creeper pods? I did a google search for trumpet creeper plus squirrels but found nothing about the aerial rodents dining on green creeper pods. I did find that hummingbirds are crazy about the flowers, so I’m glad I have the vines for that reason. Guess I’ll just have to wear a hardhat when the squirrels are attacking the pods (or me!).|
|July 18, 2006 - The tree frogs have seen the light.
I always get up early. My biological alarm clock wakes me at 4:40 am, almost to the minute, every day. I get to hear the morning bird chorus which is especially wonderful in the spring, and to watch the eastern sky slowly lighten as the sun rises. Dawn comes at 6:42 am today. The daylight hours are decreasing since the summer solstice on June 21.
I walked outside about 5:45 to see what I could see--not much since it was still dark. I heard a familiar rustling down in the garden. That cursed armadillo, I thought, digging up the flowers! I walked towards the sound and it moved off, eventually scuffling its way under the lattice fence on the north side heading for its den underneath the neighbor's house. Sometimes the dillo is out late, apparently carousing with the other dillos, and doesn't get home till after dawn. It is very near-sighted and ambles right past me without noticing that I am standing practically in its path berating it for its vicious ways. Dillos are very thick-skinned.
|Going back upstairs, I happened to look up at the porch light by the door. There lined up in a row on the wall under the light were four tree frogs! I ran inside and grabbed the camera. The frogs posed obligingly, no doubt stuffed from eating bugs all night and not caring to move anyway.|
The photos were taken with an Olympus C7000 digital camera (7 Mp) using only the porch light. The picture has a yellow color because the porch lamp is inside a yellow globe--supposedly to make it unattractive to night-flying moths and beetles. Obviously the frogs know this doesn't work because they congregate there every night to feast on the little moths that come to the light. I corrected a bit in the cyan and magenta to bring out some of the green of the frogs, but otherwise this is how it looked.
|July 16, 2006 - We have some new babies!
My wife came running into the house this morning to tell me that she had just caught a snake. She had just seen it in the garden and clapped a flower pot over it. I grabbed the camera and headed downstairs with her. We walked along the path to the potting area and there was the big pot up-ended over the mystery reptile. It was right in the path ahead of me, she said, and I stopped to watch it. I moved closer but it did not seem to see me so I took one of the big pots and carefully lowered it down over it. As she said this, she slowly lifted the pot and I saw a very pretty little creature with red, black and white bands, maybe half a meter long and one centimeter in diameter. As I was trying to remember the coral snake rhyme, 'red on black, friend of Jack--red on yellow, kill a fellow', my fearless wife deftly grasped the snake and held it in her hand.
|By then I had the camera ready and snapped the picture. It isn't a coral snake, I told her. The red and black bands are next to each other. I knew that, she said. Besides, she continued, coral snakes have to chew to inject their venom, so even if this one had tried to bite, I could have pulled it away. See, what I mean? Fearless!
So, our little fellow was a young king snake. That's a new species for the garden. We have a resident indigo snake, a rat snake, a chicken snake and once we did see a genuine coral snake. I have several brush piles around the garden that they seem to favor and there is an abundance of tree frogs and toads for them to eat. The red-shouldered hawks nesting around the property catch snakes sometimes particularly when they have young to feed, but our old-timers must have learned how to avoid them. Hopefully our baby king will survive and stick around to join the others.
|Our house and garden are home to a large population of lizards--mostly swifts, but a few anoles, blue-tailed skinks, broad-headed skinks and race-runners. I find their round eggs in flower pots, egg cartons and once inside an old bird's nest. The swifts mate repeatedly all through the long summer and every rock, post, table, chair, railing and fence has its resident swift prowling for bugs and ready to chase any interlopers away from its territory.
My wife had a wonderful experience a few years back. I had just found a couple of lizard eggs while digging in the garden. They were heavy and apparently still contained embryos. I carried them into the house to show her and put them into her hand so she could feel their weight. They are quite large relative to the size of a female swift and it is amazing that they can lay such a large egg. A chicken laying an egg the size of an ostrich egg would be about the same proportions. Just then she said, I can feel something moving! As we watched, one of the eggs rolled a bit in the palm of her hand and a small hole appeared in one side of it. Soon a tiny snout poked out and the hole was quickly enlarged as two legs appeared. With a wriggle the tiny swift popped out of the shell trailing a bit of yolk sack and perched on her finger. What a great treat to see the birth of one of our favorite critters! We watched the baby for a while then took it out to the garden and turned it loose amongst the marigolds.
|This is a picture of a swift we just saw this morning sunning on the patio. It is about 3 cm long, including the tail, and probably just hatched a few hours ago. I was able to take this close-up from about 6 cm away without it's even moving. There's a bit of sand sticking to its back, probably where some of the yoke was adhering when it made its way out of the shell.|
|Jan. 2, 2005 - The seasons are confused in Florida!
Today, the second day of the New Year, the high temperature here in Florida was 82F! There were patchy clouds in a sunny blue sky and a bit of breeze, but the air was definitely not wintry. The hickories are the last of the deciduous trees to lose their leaves here and they give us some Fall color in January. This particular tree is later than the others in shedding its leaves for some reason. The big hickory that shades the house has been dropping leaves for the past two weeks and is now looking more branchy than leafy. Since they are so tardy in shedding their leaves, the hickories are the last trees to get their new leaves in the Spring.
|The warm temperatures have stimulated some of the azaleas to start flowering; but sometimes we will get a frost and the flowers will get nipped. Usually, though, more buds will come on later.|
|The swifts also have to contend with the fluctuating temperatures. They become less and less active as it gets colder till below 60F I don't see them at all; but then when we have a warmer day with a high temperature above 65F, out they came to sun themselves on the deck and scan the vines for the odd bug. The swifts are by far the most abundant lizard species here, although they share the territory with a few anoles. The skinks who forage in the leaves and litter must be especially cold intolerant because I haven't seen them since September. The little green tree frogs also must be hidden away somewhere safe till Spring comes for certain.|
|The rice paper plant flowers are still attracting insects although there are only a couple of honey bees now and none of the flower flies that i had seen three weeks ago. Their place has been taken by large active paper wasps. The insects single-mindedly go after the nectar and pay no attention to the camera lens poked into their faces. This picture was taken in bright sun at a shutter speed of 1/125 sec. The wasps are moving all the time and on a cloudy day, I would not have been able to get a very clear picture of them. My Olympus C-7000 has a super-macro closeup setting that allows me to focus at a distance of about 3 inches from a subject, which means I can get really good bug and flower shots.|
|Dec. 28, 2005 - One-legged grasshopper jumps well!
Wednesday morning, after breakfast as usual I went downstairs to work in the garden.The temperature was about 55F (13C). The north side of the house is shaded by the oaks and hickories till about 10 am and stays cooler in the morning than the backyard which gets the first morning sun. As I walked past the bed of bromeliads I was surprised to see a large, handsome grasshopper perched on the side of the house. The length was about 3 inches (7.3 cm) and the color was a beautiful mottled gray and black. I grabbed the camera and took some pix and the hopper jumped down onto the grass. That's when I noticed he was missing one of his large jumping legs. Surprisingly, he was still able to jump although not with the distance or accuracy that he would have had with both legs. The good leg seemed unusually well developed, just as a human who lost one arm becomes especially strong in the remaining arm.
|I tried identifying the hopper and decided that it must be in the genus Schistocerca, the bird grasshoppers, so named because of their large size and strong flying ability. Turning to my favourite bug photo site, Whatsthatbug.com, I found a picture of one called the gray bird grasshopper, Schistocerca nitens, that seems to fit the appearance of mine pretty closely. If there are any grasshopper specialists out there, please let me know if that is the correct identification. By its large size, I would also say that it is a female. Here's another photo-id of the hopper from CalPhotos insect photo database. It seems to be a good match, although some variation in coloring and pattern is natural.|
|Here is a head-on view of the hopper showing the large compound eyes that allow him a horizon-to-horizon view of any predators (or nosy cameramen!).|
Dec. 17, 2005 - Christmas bird count
Cay and I went on the Christmas bird walk Saturday to participate in the annual census of U.S. birds. This tradition dates back to the late 1800's and supposedly began as a contest between groups of hunters to see who could bag the most different species. In the old days, shooting was considered the only sure way to identify a bird or other animal. Audubon was a wonderful observer of birds in nature, but he too killed the specimens he wished to paint in order to study the form and color better. On Christmas day 1900, Frank Chapman and members of the fledgling National Audubon Society decided to replace the annual bird shoot with a bird count. On this first census, the teams were able to log a total of 90 bird species throughout the United States and Ontario. Since that day, every year around Christmas all over the United States, teams of dedicated birders venture forth between 5 and 6 am on a December morning, in some cases braving snow, ice storms, and below-freezing temperatures, to take their local bird tally.
Florida birders have a definite advantage over their northern counterparts when it comes to weather during the count. The temperature on the day of our count was in the upper 50's, but it did not warm up much because the sky remained cloudy all day. Rain was the worst thing that we faced, but it was light and stopped after only a few minutes.
The bird census is taken over a circular area about 10 miles in diameter roughly divided into sectors that are searched by individual teams under an experienced leader. Some of the sectors include lakes, ponds and rivers while ours was primarily fields and open woodlands in the Withlacoochee State Forest. We met at 6 am at a convenience store on the route to our first target area where we expected to see, or at least hear woodcocks. Actually, the first bird recorded was a great blue heron that flew over the parking lot to land in a nearby ditch that had water in it from a culvert. This was about an hour before sunrise which was at 7:15 am.
We left the store and drove east on the access road which soon turned to hard-packed dirt. There was no one else on the road, and with the heavy cloud cover it was very dark when we pulled over and parked on the edge of the road. There was a large field across the road where woodcocks were known to display and we walked across to it listening for any sounds. Except for a distant dog's barking, the quietness was almost tangible. One could even hear the sound of the light wind playing in the trees adjacent to the field. It was chilly and I was grateful for my down vest and hat. We waited, listening and I caught the ringing note of a killdeer a good ways off but no sign of the elusive woodcock, whose distinctive, frog-like 'eeent! is unmistakable.
The minutes passed, and we exchanged whispers about the chilly wind, the wonderful quiet and the lack of birdlife. We split up and walked both directions on the road then came back. The gray light of dawn showed silhouettes of trees and the light-colored road. We gathered in front of a clearing behind a fence and were just about to head back to the truck when I saw a bird fly down right in front of us about 10 feet away in the clearing. The others saw it too. I got it in the binoculars just as it emitted a loud, nasal EEENT! It was our woodcock, come to reward us for our steadfastness in waiting for his appearance! Through the glass I could just make out the long sharp beak and the streaky markings on the back but little else because of the darkness. He gave a few more calls, then rose and quickly disappeared, and that was all we saw--but what a gift! To have such a secretive bird as the woodcock land right in front of us and break the stillness with his wild calls was something I shall always remember.
Above is a cluster of ripe beautyberries (Callicarpa americana)
which catbirds, mockingbirds and others like to eat.
|This photo shows a typical Florida 'scrub' habitat of grassy areas with small shrubs (Florida rosemary, saw palmetto, scrub holly} bordered by sand pine and turkey oak. We parked along the side of the road and fanned out through the grass to see what we could flush out. Immediately 4 or 5 little brown birds ('LBB' in birder lingo) popped up out of a clump of scrub St. Johnswort, flew for about 6 feet and disappeared into the grass. More appeared as we walked, but they continued to flit around inside clumps of grass and shrubs and were very hard to get a clear look at. Eventually we were able to get one in the binoculars long enough to identify it as a Savannah sparrow.|
We now drove to the red cockaded woodpecker (RCW) site which was off the road on one of the side trails. By now it was after 7 am and light enough to see easily. The woodpecker trees were in an area some 100 by 200 feet. I counted 8 trees with holes about 20-30 feet up. One sign of an occupied nest is a whitish stain spreading down the tree below the hole from the bird's droppings. After looking at one of the nests through the 60x spotting scope, I remarked to our team leader that the hole certainly was perfectly round. She then explained that the holes were not made by the birds, but by park rangers. The nest sites were created by cutting out a cavity in a living tree, usually a pine, then inserting a 2 inch PVC pipe for the opening and cementing up the hole around it. I could just make out a lattice around the hole that I assume was like the metal mesh that housebuilders use for support and reinforcement in making plaster walls.
Well, we must have waited for at least 30 minutes before one of the birds peeked out of the hole. All I could see was a short black bill and a black and white face. A couple of birds appeared in holes in other trees, but it was another 15 minutes before the first one finally flew out with a rattling cry to alight on a young pine nearby. Now the others started to move also. There seemed to be a patch of sap on the pine that the birds perched at, maybe eating any bugs that had come to the sap and got stuck. It was too far away to see clearly. The RCW’s are a bit smaller than a red-bellied woodpecker and in winter have no red cockade. The ladder back and black crown are good field marks.
|After logging the woodpeckers, we walked back along the trail to see what we could find in the pine/turkey oak scrub. There were lots of LBB’s flitting around in the understory and the canopy. Some were palm warblers (tail-waggers) and some were pine warblers. We also saw several phoebes, a few chickadees and titmice, and heard the calls of a pileated and a downy woodpecker.|
Our next rendezvous was at a dairy farm where we had gotten permission to walk through the fields and pastures. There was a long drive between two fenced fields up to the two-story farmhouse. Many killdeer were in the field along with some more Savannah sparrows. There were 6 bluebirds dancing around the shrubs along the fencerow and more sparrows. We saw one vesper sparrow, a relatively uncommon species for this area. There’s barbed wire along the drive, but we were able to slip between the strands and walk in the field where there were several large oaks.
|This was the best area yet for many species. We immediately began logging red-headed woodpeckers, kestrels, a harrier, a pair of bald eagles, many white ibis and a group of 5 glossy ibis around the slough in the center of the field. There was a snipe and a cormorant, crows calling, some anhingas flying over, mourning doves perched on the telephone wires and a couple of yellow-rumped warblers flitting around in the tree canopy. I startled a pair of barred owls in one of the big oaks but I didn’t get more than a flashing look at them—enough to say that they had no ear tufts, but not to be able to positively identify them. The others saw them clearly and said they were definitely barred owls.
We next drove up to the top of the hill where the milking barn was and looked around there for an hour or so. There were more palm warblers, Savannah sparrows, and I spotted one song sparrow—at least I am fairly certain that is what it was because of the prominent breast spot. More kestrels, killdeer, doves, ibis, and a fine pair of red-shouldered hawks were seen. After lunch we drove past the house into the field behind. Here we saw a single meadowlark at last, then another, and a couple more until finally an entire flock of about 20 started up and flew off. We then drove to a stand of oaks and understory and looked but noted only a pair of cardinals. There were several red-shouldered hawks cruising over the field and one caught something while we were watching.|
The rest of the trip was uneventful. We located a field where burrowing owls had been seen, but they weren't out today. Maybe the lack of sun, spatterings of rain and cooler temperatures made them reluctant to leave their warm nests. I thought again about those ardent Christmas bird counters in the northern states where the winter weather had already turned pretty fierce. I wished them a warm fire and a cup of hot chocolate at the end of the trail.
Dec. 20, 2005 - December in Florida|
Here in north central Florida, the winters are mild compared to other southern states, though not as warm as southern Florida. We have had temperatures in the upper 30's a couple of mornings, but no frost yet which is a bit unusual since the average date of first frost for Sumter county is the first week of December. The cooler mornings have caused our swifts, anoles and geckos to stay in bed later than usual and yesterday when the high was 55F, I saw only a couple of polar bear types in the sun on the deck. We must have a fairly large population of lizards and frogs living in various nooks of the house because during the hot summer there is scarcely a part of the deck, railing, post or wall that does not have its resident male, challenging all interlopers while staying on the lookout for females. Often when I move a box or a tool that is stored in the work areas next to the house, I will find a chilly tree frog or swift behind it. It is a good feeling to know my insect-eating allies are being protected here and will be on the job limiting the bug population in the spring.
|The cooler weather has reduced the insect population as well as the lizards. I see very few butterflies and moths now, the cicadas have ceased their summertime shrilling and only a few flies, wasps and bees are around. I try to grow plants that will provide food for butterflies, wasps and bees so that I will have lots of them--butterflies for beauty, wasps as predators on other bugs and bees to pollinate the garden. One of the best plants I have found for late fall bloom here is the rice paper plant, Tetrapanax papyriferus. I have a row of them planted along the property line on the west side where they get the warm afternoon sun. I was walking out there this past Sunday, and the plants were literally humming with activity. A steady stream of bees, flower flies, wasps and a couple of moths that try to imitate wasps were covering the creamy white flower clusters. I have read that in their native Formosa, the plants can grow to be small trees 30 feet tall, but here they only reach a modest 6 feet or so. The flower clusters are something amazing, though. Imagine an arrangement of stalks jutting out from a central stem with a myriad of one inch white balls all covered with downy hairs and you have some idea what the inflorescence looks like.
|The greatest number of visitors to the flowers are honey bees. They have a colony in the big sweetgum at the end of the fencerow. One can watch a steady flow of traffic going out from the nest and returning like an insect interstate. I have wondered what would happen if I stood up in the flight path. Would they attack me to get me to move out of the way? I don't think so. If I stayed still, I think they would simply fly around me as if I were a tree that had somehow appeared in their environment. I haven't got up the courage to try the experiment, however.|
|The flies are interesting. They belong to the family known as Syrphids (from the Greek, syrphos, meaning gnat) which includes hover flies and drone flies in addition to the flower flies. Using the online bug guide I have tentatively identified the flower fly as Eristalis palpada. Their larvae are good for the garden because they eat aphids, thrips and caterpillars. The adult flies have come to resemble wasps and bees to such an extent that they intermingle with them unmolested on flowers, and other insects that prey on flies leave them alone thinking that they are just another bee. One has to be pretty smart and resourceful to survive in the bug world. I would not care to try it.|
|I photographed two kinds of wasp-mimicking moths visiting the rice paper plants. The one with the bright red body is, logically enough, the scarlet-bodied wasp moth, Cosmosoma myrodora while the other is called the white-tipped black geometrid, Melanchroia chephise.|
|The rice paper plants are so named because their stalks have been made into a beautiful white paper that watercolor artists paint upon and calligraphers use for lettering. I would like to try making the paper, but I will wait until winter has truly come before I disturb the wonderful ecosystem that helps to keep the balance of Nature in my small part of the planet.|
| The squirrels around our house are a very entertaining bunch and I enjoy watching them in spite of their never-ending attacks on the bird feeders. One day I was sitting at the table in front of the big window that faces the deck when I saw a squirrel lugging something along a branch. I grabbed the binoculars and looked to see what he had. At first I could not make it out. It was whitish, flat and fairly large. He stopped, and holding it with his paws he began to gnaw one edge of it. Then I realized what it was. A bone! At that instant he lost his grip on it and it fell to the ground. Seizing the opportunity, I raced outside and into the trees in the back yard to try to find the dropped object. It was a flattish bone about 4 inches square with a slight curvature. I think it might have been one of the bony plates of a turtle. Being near the river we have lots of sliders, soft-shells and others. The edges of the bone were all gnawed and it was evident that the squirrel had been working on it for some time. I carried it back to the house and left it on the railing of the deck where I could watch. Sure enough, later that afternoon a squirrel--I think it was the same one--hopped onto the deck and picked up the bone. I was ready with the camera and snapped
the picture as he again applied his teeth to the edges. After a few minutes he jumped into the nearby oak, still carrying the bone and disappeared into the woods. Why would a squirrel gnaw on a bone? For the calcium or just because it tasted good? They seem to eat just about anything. One even seemed to relish a chicken leg bone that I threw to it! I have seen them carrying whole mushrooms, apple cores, bananas, and once a dead baby bird. But that was the first time I'd seen one toting around a bone to gnaw on.
| Hurricane Jeanne hit the east coast of Florida near Vero Beach early Sunday morning, Sept. 26, and traveled north through the interior of the state. Our house in the north central part was not damaged by the wind and rain but the nearby Withlacoochee river flooded and destroyed several homes along its banks. Our house is above the 100 year flood line, so we should be safe barring a really catastrophic storm. We went walking in the woods across the street after the storm was gone. Many trees had been blown over or snapped off and the trails were all blocked or under water. The photo shows the river covering most of the area below our house that is normally a forest path. The oaks and hickories and other trees are used to having their roots underwater periodically, but I think more than a couple of weeks without oxygen and they might die. The cypress trees are adapted to an underwater environment but all an oak can do apparently is add buttresses to its base to keep from tipping over.
| Even the bullfrogs found it too much at times and headed for higher ground!
| Jerry Taylor landing, a canoe put-in on the Withlacoochee River, is about a two-minute walk from my house. 'Withlacoochee' is a Seminole word meaning 'man's crossing'. I take that to mean fordable because here, and at several other points on the river, the water is so shallow that you can walk across without even getting your shorts wet. In the summer, however, when the daily thunder and lightning bring torrential rains ('frog-stranglers' according to the locals) the river swells and overflows its banks and you would have to swim across. The water still moves north at a relatively liesurely pace--it's just a lot wider and deeper at the center.
Have you ever seen a full-grown wild hog swimming? Neither have I, but they must do it because the hog wallows on this side of the river are always freshly dug up. The hog families live across the river on Hog Island but they all come over to the Jerry Taylor side to do their rooting around. Maybe there's some roots or grubs that they especially like on this side. Like humans, hogs will go the extra mile for a good dinner.
|This webspinner is called an argiope. She is a fairly common inhabitant of the woods near my house and I never fail to admire her striking black and yellow stripes and the singular X-shaped silk of the web. Spiders can be a bit scary indoors but one need not be afraid to meet them where they normally live. Like our other allies, the toads, spiders consume vast amounts of bugs that otherwise might be munching on our flowers and fruits. Did you notice that she sits in her web facing downward? Why do you think that is? Actually I do not know. Other types of spiders normally sit with heads facing upward. In general spiders have multiple eyes and must see the world in a very different way from us. Perhaps Argiope sees better with head down. The name 'Argiope' is the Greek name for one of the nature deities known as nymphs. If you would like to read a story from Greek mythology about a tapestry maker named Arachne who challenged mighty Athena to a weaving contest, and how her name came to be associated with the spider family, the Arachnids, go to this website.|
|Now here's a pretty plant--aptly called blue-eyed grass. It isn't a true grass although the thin, blade-like leaves and the clumpy growth habit suggested that to the person who named it. The plant is a member of the iris family, Iridaceae, and its genus name is Sisyrhinchium. It is a naturalized wildflower here in Florida and I have transplanted several clumps to my garden. The plants have tiny bulbs that can be separated from the roots and replanted to sunny beds where they will reward you with a wonderful profusion of sky-blue flowers in the spring.|
We have had a wet summer and the mushrooms and other fungi are abundant. The part of the fungus that you see in the picture could be thought of as the 'flower' because it produces the spores which are the 'seeds' of the fungus. The 'root' system which is called the mycelium, is a network of fine, interconnecting tubes that has grown over and through the surface upon which the fungus lives. This may be the wood of a dead tree, the mat of decaying leaves on the forest floor, or sometimes the bark of a living tree. While there are fungi that cause disease, the majority are extremely useful as decomposers of dead vegetable matter. They are a critical part of the recycling crew that takes dead leaves, fallen branches, fruit, and other plant detritus and breaks it down into raw materials that can be used by new plants.
|        What is that strange growth on the fallen branch? It looks like a round black cinder or piece of charcoal. It is another fungus named, aptly enough, carbon mushroom or Hypoxylon. It shows how amazingly varied are the forms of mushrooms--from the familiar Agaricus bisporus of the grocery store to puffballs and morels and fungi that resemble a bird's nest even to the presence of tiny 'eggs'! Though it does not have a form that most people think of as being a mushroom, the actual body of the carbon fungus--the stringy network of mycelia growing throughout the fibers of wood on a dead tree--is similar to that of other fungi. The fruiting body which is the organ that produces the spores and disperses them into the air is the part of the fungus that shows the greatest diversity in form and color.|
The plant matter that was 'digested' by the fungi is put back into circulation as nutrients in the soil. Some plant products are not very digestible, however. Tannin or tannic acid is a chemical produced by oak trees particularly, but other trees as well; and oak leaf litter will make the soil acidic partly due to tannic acid. When rain comes and washes the tannins into rivers, the water is stained a brown color like tea. This photo was taken in a swamp where there is a continuous process of growth and decay and tannin production. Water with dissolved tannic acid can be quite acidic with a pH of around 4 or even lower. The acid helps to dissolve minerals from the soil and provide nutrients for the swamp plants. By the way, do you know the difference between a swamp and a marsh? A swamp has trees and a marsh does not.
|        Let's walk on the trail that skirts the swamp and see what we can find. The heavy rains this summer raised the water level several feet, but the river has mostly returned to its banks now and the trail is visible once again. Look at the trunks of the big cypress trees. You can clearly see the water line. Many trees would die if their roots were submerged for more than a week, but cypresses have evolved special structures that allow them to grow with their feet in the water. These are called 'knees' and form clusters of protruding columns around the tree's base like stalagmites in a cave. The knees or pneumatophores, which means 'air-carriers', may help the roots to breathe. Large cypresses may have dozens of knees some four or five feet tall and as thick as a small tree. Another characteristic of the bald cypress, Taxodium distichum, is a wide base with buttresses like those on a medieval cathedral that support the massive trees in wet soil.|
Willow, water tupelo, green ash and laurel oak are some of the other trees that are able to live in ground that is periodically flooded like this area along the river. They are still in danger here, however, because the lack of oxygen in the lower layers of soil prevents their roots from going very deep and providing the support needed for a big tree. There is an oak next to the trail that tipped over this year, but has still managed to survive. Its branches are growing vertically from the prostrate trunk while the disk of roots which is about six feet across continues to provide enough nutrients. Possums and raccoons use the trunk as a runway. Possums are frequent visitors around the house. This young one appeared on the fence during the day--unusual for an animal that is primarily nocturnal. It stopped to peer at me as I photographed it then continued on slowly walking along the fence to disappear in the trees at the far end of the property.
|        Look on the base of that pine. There's a mushroom growing on the bark. Most mushrooms that grow on tress grow on dead wood, but this one favors living trees although it does not harm them. It is in the family Strobilomyces. The 'strobiles' refer to the small scale-like parts on the cap that give it the appearance of a shag rug. In fact, we call it the pink bathrug fungus.|
Here on the dead branches of an oak is an odd mushroom commonly known as witch's butter because of its orangey-yellow color and its smooth shiny surface. For a more detailed description of this mushroom family, see the Fungus of the Month site . The other mushroom pictured here is also a 'jelly' fungus with a rubbery body. As you can see, not all mushrooms have the parasol or toadstool shape we have come to associate with a mushroom. Fungi have evolved an amazing range of shapes, textures and colors, and learning to identify some of the more common ones is a worthwhile addition to your nature walk. Get a mushroom field guide that is specific for your area if you can because there is considerable regional variation in size, form and coloration within a single species. A good field guide will have a key, a long list of features that you follow sequentially to identify your particular mushroom. Learn the scientific terms for describing the cap, stem, spores, growth habit, etc., and you should be able to identify at least the genus of most mushrooms.
|This dead tree is wearing a mushroom jacket. Fungi help break down the wood fibers and speed up the decomposition process that recycles plant materials. The fungi have a thread-like network called a mycelium that penetrates throughout the wood. The cells of the mycelium secrete enzymes that digest the wood fibers to provide nutrients for the fungus. Eventually the dead tree falls over and breaks down completely to become part of the forest soil again. Other trees take the nutrients from the decayed tree to complete the cycle.|
Ecology is the study of habitats and the interactions among the living things that occupy them. Fungi are an important part of a forest ecosystem. Together with soil bacteria, they form a group of organisms that many people simply overlook or think of as harmful. Just the opposite is true. Many trees have a working relationship with specific types of fungus that provide nutrients and other substances to their roots. These fungi are called mycorrhizae from the Greek words 'mykos', mushroom, and 'rhiza', a root. The mutually beneficial association between the tree and the fungus is known as symbiosis.
|The tree roots provide sugars and other carbon compounds to the fungus while the fungus in turn passes inorganic salts and minerals to the tree. The mycorrhiza forms a wide-spread network of mycelia in the soil like the arteries and capillaries of an animal's circulatory system. The roots of the tree are connected to this network and thus are able to obtain minerals and water from a much larger area. The tree grows faster because of the fungus and can fight off disease and insect predation better than trees lacking mycorrhizae. |
Trees are not the only plants that enjoy the company of fungi, however. Almost all vascular plants can be found to have mycorrhizae under some conditions, and the fungi make them more fit and able to withstand environmental stresses. Many of the mycorrhiza tribe form mushrooms that we can see on the forest floor. It is incredible to think that the part we see is literally only the tip of the iceberg because the mycelia may cover an area of several square meters within the soil. If you are as fascinated as I am by mushrooms and the role they play in the life of the forest, then you might want to check out some 'shroom websites to learn more. A good place to start is with the MykoWeb homepage which contains lots of information and links to over 200 mushroom sites on the web.