Previous Nature Walks - Vol. 2

Feb. 27,2011 - Our redbud tree trunks are flowering!

I have a large redbud tree, Cercis canadensis, in my yard and it blooms faithfully every year with hundreds of small pink flowers. The unusual thing about the tree’s flowering is that the reddish magenta buds shoot out directly through the bark of the trunk and branches before they open to reveal the flowers. I have never seen another tree do this and I wondered if the redbud might be the only one. Searching the web, I found that there are many such trees, over a hundred species, and most are found in the tropics. In fact, there’s even a name for this out-of-the-trunk type of flowering— cauliflory, which means ‘stem flowering’. The chocolate tree has flowers that emerge from the trunk, and after being fertilized turn into the pods of cocoa beans from which our chocolate comes. There are also a couple of different species of tropical fig that practice cauliflory along with the useful breadfruit tree of southeast Asia and the well-known papaya. Why do these trees have flowers on their trunks? There are several possible reasons and naturally they all have to do with the plant’s reproduction. The flowers have to be pollinated in order to form fruit and this may be done by insects or mammals that can get to the flowers most easily by climbing up the tree trunk. Some of them are fertilized by bats that hang onto the trunk and move around from flower to flower. Once the fruits form, the tree wants to disperse its seeds in order for new trees to grow, and fruit hanging off the trunk is easily accessible by monkeys, birds and bats who carry it off and deposit the seeds in their droppings. My redbud tree flowers are definitely being pollinated because they always form three inch green pods some time in March or early April. Now I can hear the hum of bees and wasps visiting the flowers for their nectar and see the insects by the dozens flying around the trees. Something must also be eating the pods after they have formed and dispersing the seeds because I find young red bud trees growing everywhere in the yard. I’ll have to watch this year and see what is eating them—maybe squirrels. Eastern redbuds are an easy-to-grow tree that can reach a height of 20 feet in just a few years. They are absolutely beautiful in the spring when covered with pink blossoms. The pretty, heart-shaped leaves begin to emerge while the flowers are still maturing into pods. Plant one tree and you will always have a continuous supply of babies to give to friends as gifts. And you can tell them they are getting a special tree that knows how to do cauliflory!

Southern crevice spiders are mating!

We have some Southern crevice spiders (Kukulkania hibernalis) in our house and from time to time, they are visited by males of the species bent on making babies. I happened to see an especially handsome young swain courting one of our girls one morning early before dawn. I took the succession of photos shown above over the space of about three hours, which gives you some idea how slowly the male approaches the female. As he advanced toward her, she demurely retreated towards her crevice until she was totally inside with only a bit of leg sticking out. Spider reproduction is fascinating. In many cases, the male makes a little mat of silk onto which he deposits the sperm. He then takes them up in his pedipalps and advances towards the female--cautiously, lest she mistake him for a potential meal. The details of the courtship ritual vary among the different types of spider. I have seen male crevice spiders tapping the legs of the females with their feet, and this may be how they ascertain whether she is receptive. The actual mating, which I have never witnessed, involves the male carefully approached the female from underneath, and depositing the sperm in the epigynum, a tiny slit on the underside of the abdomen. He then slowly retreats. Contrary to what many people believe, most female spiders do not eat their mates after mating. I don't know if the males can produce more sperm and impregnate more female spiders, or whether they simply die after having served their purpose. Assuming our boy was successful--and he was still there with her the next day--there will be an egg soon and in time a bunch of little spiderlings. I will do a follow-up photo of the blessed event when (and if) it happens.

Mushrooms are stronger than they look!

This is a strange story, but true. I have a workshop outside under a 10 x 20 ft canopy and to keep it cleaner, I put down some pieces of old outdoor carpeting on the ground. Well, I went out to get some wood from the workshop last weekend and I noticed an odd hump in the carpet. I felt it and it was firm and hard. Thoroughly curious now, I moved the stuff off the carpet and lifted up the edge until I got to where the hump was. I expected that a root must have put up a sprout there but to my astonishment, I saw a dark reddish brown lump about two inches across with a rough fibrous texture. I felt it and it was hard. I pulled at it and to my surprise it came right out of the ground and I immediately realized that what had raised the carpet was a mushroom! I have been photographing and identifying mushrooms for many years but never have I seen one like this. The body had no gills or tubes or pores that I could make out, but seemed to have a sort of knob-like cap. Its growth was impeded by the carpet, however, so its true shape and size might have been different. Being interested in fungal anatomy, I decided to see what was inside. Using a sharp razor knife, I sliced through the mushroom vertically from the cap to the base. The inside was solid but there seemed to be an area containing some cinnamon brown spores and other areas with lighter colored markings.

I have several mushroom handbooks but it still took some time to find this weird fungus. The genus is Pisolithus, but I'm not sure of the species. There are two common species, tinctorius and arrhizus. If you are familiar with botanical Latin, you know that 'tinctorius' means 'dye-producing', a reference to the capability of this fungus to be used for dying wool. The other useful feature of this fungus is its ability to form a mycorrhizal symbiosis with a variety of trees. Foresters and environmental restoration groups sometimes include some of the fungal spawn in the dirt used in planting tree seedlings. The fungus forms a mycelium that interacts with the young tree's roots enabling them to take up nutrients better. The seedling trees planted with Pisolithus grow faster than those without the fungus.

I examined the spores under the microscope and found them to be round, about 10 microns in diameter, with tiny projections. This fits with the descriptions in the mushroom keys for Pisolithus. Here are some of the references in which I read about Pisolithus: 1. http://www.bayareamushrooms.org/mushroommonth/pisolithus.html 2. Kuo, M. (2006, November). Pisolithus tinctorius. Retrieved from the MushroomExpert.Com Web site: http://www.mushroomexpert.com/pisolithus_tinctorius.html 3. http://en.wikipedia.org/wiki/Pisolithus_tinctorius

Unlucky damselfly escapes one fate only to fall prey to a waiting tree frog.

This morning about 6:30 am I was coming back inside when a damselfly flew in through the door at the same time. Insects are attracted to our porch light even though it is yellow, which they are supposed to ignore. Moths, wasps, beetles and other critters congregate on the wall around the light and are always flying inside when I open the door. I keep a wide-mouth pint jar with a lid handy and I can usually trap the bug in the jar and take it back outside. Any that I miss can end up as dinner for one of our house spiders, so it is in their best interest to let me trap them. This particular damselfly refused to stop flying and settle onto something I could get the jar over. I went back to working on the laptop but kept one eye on the fluttering creature. Eventually it must have gotten tired because it landed on a curtain and stayed there. I quickly got the jar over it and the lid on after it flew inside. Success! I thought as I walked over to the door and opened it. I carefully closed the door behind me so that the damselfly couldn't fly back inside after I released it. The one thing that I neglected to do, however, was turn off the porch light. As soon as I took off the lid, the damselfy made a beeline for the light. As bad luck would have it, a green tree frog had taken up his station right under the light where he was patiently waiting for bugs. The hapless damselfly flew right under the light, right in front of Mr frog, who naturally snapped him up for breakfast. I figured there was little chance of rescuing the creature alive and so grabbed the camera and at least got a picture of the grisly scene. Well, frogs have to eat, and I especially like our green tree frogs who always croak when its going to rain and are a colorful addition to the walls and the windows. Adult damselflies only live a few days. Hopefully this one was able to lay her eggs near the pond before her demise. That's the dilemma of a biologist. We are not supposed to interfere with the natural predator-prey relationship; but, Gee! What rotten luck!, I thought.

I have a large redbud tree, Cercis canadensis, in my yard and it blooms faithfully every year with hundreds of small pink flowers. The unusual thing about the tree’s flowering is that the reddish magenta buds shoot out directly through the bark of the trunk and branches before they open to reveal the flowers. I have never seen another tree do this and I wondered if the redbud might be the only one. Searching the web, I found that there are many such trees, over a hundred species, and most are found in the tropics. In fact, there’s even a name for this out-of-the-trunk type of flowering— cauliflory, which means ‘stem flowering’. The chocolate tree has flowers that emerge from the trunk, and after being fertilized turn into the pods of cocoa beans from which our chocolate comes. There are also a couple of different species of tropical fig that practice cauliflory along with the useful breadfruit tree of southeast Asia and the well-known papaya. Why do these trees have flowers on their trunks? There are several possible reasons and naturally they all have to do with the plant’s reproduction. The flowers have to be pollinated in order to form fruit and this may be done by insects or mammals that can get to the flowers most easily by climbing up the tree trunk. Some of them are fertilized by bats that hang onto the trunk and move around from flower to flower. Once the fruits form, the tree wants to disperse its seeds in order for new trees to grow, and fruit hanging off the trunk is easily accessible by monkeys, birds and bats who carry it off and deposit the seeds in their droppings. My redbud tree flowers are definitely being pollinated because they always form three inch green pods some time in March or early April. Now I can hear the hum of bees and wasps visiting the flowers for their nectar and see the insects by the dozens flying around the trees. Something must also be eating the pods after they have formed and dispersing the seeds because I find young red bud trees growing everywhere in the yard. I’ll have to watch this year and see what is eating them—maybe squirrels. Eastern redbuds are an easy-to-grow tree that can reach a height of 20 feet in just a few years. They are absolutely beautiful in the spring when covered with pink blossoms. The pretty, heart-shaped leaves begin to emerge while the flowers are still maturing into pods. Plant one tree and you will always have a continuous supply of babies to give to friends as gifts. And you can tell them they are getting a special tree that knows how to do cauliflory!

Southern crevice spiders are mating!

We have some Southern crevice spiders (Kukulkania hibernalis) in our house and from time to time, they are visited by males of the species bent on making babies. I happened to see an especially handsome young swain courting one of our girls one morning early before dawn. I took the succession of photos shown above over the space of about three hours, which gives you some idea how slowly the male approaches the female. As he advanced toward her, she demurely retreated towards her crevice until she was totally inside with only a bit of leg sticking out. Spider reproduction is fascinating. In many cases, the male makes a little mat of silk onto which he deposits the sperm. He then takes them up in his pedipalps and advances towards the female--cautiously, lest she mistake him for a potential meal. The details of the courtship ritual vary among the different types of spider. I have seen male crevice spiders tapping the legs of the females with their feet, and this may be how they ascertain whether she is receptive. The actual mating, which I have never witnessed, involves the male carefully approached the female from underneath, and depositing the sperm in the epigynum, a tiny slit on the underside of the abdomen. He then slowly retreats. Contrary to what many people believe, most female spiders do not eat their mates after mating. I don't know if the males can produce more sperm and impregnate more female spiders, or whether they simply die after having served their purpose. Assuming our boy was successful--and he was still there with her the next day--there will be an egg soon and in time a bunch of little spiderlings. I will do a follow-up photo of the blessed event when (and if) it happens.

Mushrooms are stronger than they look!

This is a strange story, but true. I have a workshop outside under a 10 x 20 ft canopy and to keep it cleaner, I put down some pieces of old outdoor carpeting on the ground. Well, I went out to get some wood from the workshop last weekend and I noticed an odd hump in the carpet. I felt it and it was firm and hard. Thoroughly curious now, I moved the stuff off the carpet and lifted up the edge until I got to where the hump was. I expected that a root must have put up a sprout there but to my astonishment, I saw a dark reddish brown lump about two inches across with a rough fibrous texture. I felt it and it was hard. I pulled at it and to my surprise it came right out of the ground and I immediately realized that what had raised the carpet was a mushroom! I have been photographing and identifying mushrooms for many years but never have I seen one like this. The body had no gills or tubes or pores that I could make out, but seemed to have a sort of knob-like cap. Its growth was impeded by the carpet, however, so its true shape and size might have been different. Being interested in fungal anatomy, I decided to see what was inside. Using a sharp razor knife, I sliced through the mushroom vertically from the cap to the base. The inside was solid but there seemed to be an area containing some cinnamon brown spores and other areas with lighter colored markings.

I have several mushroom handbooks but it still took some time to find this weird fungus. The genus is Pisolithus, but I'm not sure of the species. There are two common species, tinctorius and arrhizus. If you are familiar with botanical Latin, you know that 'tinctorius' means 'dye-producing', a reference to the capability of this fungus to be used for dying wool. The other useful feature of this fungus is its ability to form a mycorrhizal symbiosis with a variety of trees. Foresters and environmental restoration groups sometimes include some of the fungal spawn in the dirt used in planting tree seedlings. The fungus forms a mycelium that interacts with the young tree's roots enabling them to take up nutrients better. The seedling trees planted with Pisolithus grow faster than those without the fungus.

I examined the spores under the microscope and found them to be round, about 10 microns in diameter, with tiny projections. This fits with the descriptions in the mushroom keys for Pisolithus. Here are some of the references in which I read about Pisolithus: 1. http://www.bayareamushrooms.org/mushroommonth/pisolithus.html 2. Kuo, M. (2006, November). Pisolithus tinctorius. Retrieved from the MushroomExpert.Com Web site: http://www.mushroomexpert.com/pisolithus_tinctorius.html 3. http://en.wikipedia.org/wiki/Pisolithus_tinctorius

Unlucky damselfly escapes one fate only to fall prey to a waiting tree frog.

This morning about 6:30 am I was coming back inside when a damselfly flew in through the door at the same time. Insects are attracted to our porch light even though it is yellow, which they are supposed to ignore. Moths, wasps, beetles and other critters congregate on the wall around the light and are always flying inside when I open the door. I keep a wide-mouth pint jar with a lid handy and I can usually trap the bug in the jar and take it back outside. Any that I miss can end up as dinner for one of our house spiders, so it is in their best interest to let me trap them. This particular damselfly refused to stop flying and settle onto something I could get the jar over. I went back to working on the laptop but kept one eye on the fluttering creature. Eventually it must have gotten tired because it landed on a curtain and stayed there. I quickly got the jar over it and the lid on after it flew inside. Success! I thought as I walked over to the door and opened it. I carefully closed the door behind me so that the damselfly couldn't fly back inside after I released it. The one thing that I neglected to do, however, was turn off the porch light. As soon as I took off the lid, the damselfy made a beeline for the light. As bad luck would have it, a green tree frog had taken up his station right under the light where he was patiently waiting for bugs. The hapless damselfly flew right under the light, right in front of Mr frog, who naturally snapped him up for breakfast. I figured there was little chance of rescuing the creature alive and so grabbed the camera and at least got a picture of the grisly scene. Well, frogs have to eat, and I especially like our green tree frogs who always croak when its going to rain and are a colorful addition to the walls and the windows. Adult damselflies only live a few days. Hopefully this one was able to lay her eggs near the pond before her demise. That's the dilemma of a biologist. We are not supposed to interfere with the natural predator-prey relationship; but, Gee! What rotten luck!, I thought.

Lizards are temporary hibernators in Florida.

It is New Year's eve, Dec. 31, 2009, in north central Florida and the high temperature here today was about 73F. I saw a few lizards out basking and hunting bugs. Not as many as in July, but still some. How is it that lizards and frogs can go into a temporary 'hibernation' when temperatures drop below about 65F but come out of it when we have a warm day? Lizards are reptiles and these animals do not generate body heat as we do. There is evidence that some dinosaurs may have been partially warm-blooded, but this is controversial. Our fence lizards disappear on cold days and I have found them in flower pots, under boards and in pipes. Their bodies are cold to the touch but they are still able to wriggle a bit when disturbed. If you remember your general chemistry you know that most chemical reactions slow down as the temperature is reduced. Metabolism involves a lot of chemical reactions, so is that the simple explanation for the lizard's hibernation? I think the lizard's metabolic changes are more controlled. There has to be a coordinated change in all the systems. The breathing and heart rates have to slow down, digestion probably stops, brain activity is reduced; but all these functions still have to continue. The heart and lungs cannot stop completely or the lizard will die. That is why I don't believe that animals can be frozen and revived. I think the lizard's internal engine is on idle in cold weather but it is still operating. The senses and brain activity may be reduced but the lizard is not 'asleep'. Do you think a person could be put into hibernation like this? I think it will be possible to lower a person's temperature in a programmed way with perhaps mechanical assists for breathing and circulation and to maintain them that way indefinitely. In this way a crew and passengers could survive on a space voyage lasting hundreds of years, only to be 'awakened' at the destination by a programmed mechanical process. If we study how lizards accomplish this feat maybe we can learn how to create hibernation in humans.

The weather has changed and fall is here--in Florida.

In October, while people in Michigan, Illinois, Pennsylvania and New York are raking leaves, Floridians are still enjoying the greenery of late summer. We get our Fall here in central Florida in early December. I took a walk in the riverine woods across from my property this past Sunday and was surprised to see a carpet of newly fallen maple, cypress and sweet gum leaves. We had had some cool days with lows in the upper 30s and highs in the low 60s F and maybe that triggered the leaves’ abscission.

The all-day rain made everything dark and shiny and rich looking as you can see in the photos. Winter is usually pretty dry, and a soaking rain like this is a real blessing for the trees, shrubs and understory plants. The bracket fungi had also soaked up the rain and every fallen tree trunk, limb, branch and twig seemed to be decorated with buttery yellow and cinnamon-colored leaflets. I like brackets because they can last for years, growing broader and thicker with time and sporting a beautiful layered covering of reddish brown, cream, yellow and tan striations. Richard Mabey, in his wonderful book Plantcraft talks about the use of bracket fungi for tinder. Tinder used to be much more in demand before the advent of matches for starting fires from a spark.The species grows on beech or birch trees and when mature somewhat resembles a horse’s hoof. The fungi are gathered in the fall and pounded until they resemble shreds of leather. They are then soaked in Chile saltpeter, sodium nitrate, and dried, after which they are very flammable and can be ignited by a spark struck with a flint from steel. You can still buy them in some old-fashioned tobacconist’s shops under the name of ‘Amadou’. I haven’t tried making my own tinder yet, but I may do that this fall since the brackets are in such abundance. Trying things yourself is much more fun and exciting than reading about them, and you may make a discovery. How do you think the first person learned to make tinder from a dried fungus? Not by reading about it in a book! If you have an idea, test it. Make an experiment, observe the results and draw some conclusions—then do more experiments. You don’t have to be a scientist to use the methods of science. The world is a miraculous and exciting place for the person who takes the time to look, question, and experiment.

Spiders are shedding their skins!

I found a spider molt on the stairs yesterday. There are a lot of spider webs under the eaves of the house and this one may have been cast off from there. I can see some advantages to having your skeleton on the outside the way insects and spiders do: protection from the weather and from predators, no need for clothing, and lots of interesting shapes and colors. But there’s one big disadvantage. As human kids grow up, their skeletons keep pace and grow with them. Not so with a spider. An adolescent spider eats bugs and grows bigger inside, but its skeleton [actually an ‘exoskeleton’, ‘exo’ meaning outside] remains the same size. So what does the young spider do? It has to create an entire new larger skeleton from scratch inside the old one, and that’s not an easy task. For one thing, how does he make a larger exoskeleton while still confined within the old one? He can’t just take off the old one and hang around in just his skin while his cells are busy synthesizing the new body armor. Some predator would be sure to grab him in that helpless condition. When the spider is ready for a larger exoskeleton, its body goes into molt mode. A special fluid is secreted to keep the new exoskeleton separate from the old one. Otherwise parts might stick together.

Now the spider goes to work making a larger exoskeleton. As it is formed inside, the new body armor is soft and pliable, overlapping and folding in places so that it can fit inside the old rigid exoskeleton. Like your body when you are growing up, the process in a spider is controlled by specific genes in the DNA that make hormones, receptors and the enzymes necessary for synthesizing and remodeling tissue. The spider doesn’t have to think about it any more than you do. When the new exoskeleton is ready, the spider pumps up his ‘chest’ (thorax) with a lymphatic fluid until the old exoskeleton splits. Then he slowly pushes and pulls himself out through the opening. Spiders usually hide in their webs or burrows while doing this because they are vulnerable to attack. After finally freeing themselves from the molt, they pump up the exoskeleton to its full size and finish remodeling the tissue underneath. The pale translucent color is replaced by the normal opaque brown or black and the spider goes about his business with what is basically a new body, at least on the outside. Being able to replace body parts would certainly be a useful ability and maybe someday scientists will figure out how to stimulate the right genes in the right sequence to allow us to make a new heart, liver or skin. In the mean time, take care of your body because its the only one you have!

Caterpillars are defoliating the trees!

This has been one of the worst years for gypsy moth caterpillars. As you can see, my poor hickory has almost been defoliated by the ravenous insects. The ground under the tree is covered with caterpillar droppings. They fall like rain drops. Why are there so many caterpillars this year? I don't know. They vary from year to year but usually are only an annoyance and not a threat to the trees. We garden organically so I don't use chemical pesticides, but I will have to be more aggressive in using the natural control methods such as tangle-foot on the tree trunks, spraying with Bacillus thuringiensis bacteria and hand-picking and destroying the egg cases in the fall.

Mysterious piles of caterpillar droppings appear.

We have some very unusual insects around our house, or at least it seems so to me. I went downstairs on the patio one morning and noticed a neat pile of gypsy moth caterpillar droppings about 7 cm across. I knew what they were because the caterpillars are infesting the big hickory by the patio and their droppings fall like rain, littering the ground. I saw the dark mass in the center of the pile and when I looked closer I saw they were live ants! But why were they gathering the droppings? They did't appear to be eating them, but they were carrying some into the nest. This is a mystery. I have heard that there is a species of ant that grows a fungus garden underground as a source of food. They chew up plant material and deposit it in their fungus chambers then seed it with fungal spores and wait for it to grow. Perhaps my ants have developed a taste for a special gourmet fungus that only grows on caterpillar droppings. They must be in ant heaven this year because the ground is covered with the droppings. Great! Now I will have an infestation of fungus ants to deal with.

Golden orb weaver spider females are ready to mate.

The golden orb weaver spiders are huge, colorful creatures that choose our house every year as a place to build their spectacular golden webs. This one made her web right outside our living room window, so we can watch her at close range from inside. The strands of the web extend about 7 feet from the eaves of the house to the wall across the window. The spiders are tiny when young, but they quickly shed their skins and grow into 5 inch monsters such as this one. They are really quite fragile and harmless to people in spite of their size. If you look at the second photo on the right you will see a much smaller spider in the web above the big one. This is the male spider, and he is planning to mate with her. He has been getting closer and closer to her for several days. The drive to mate must certainly be strong in spiders!

When he is close enough, he will make a sperm packet with some of his silk and VERY carefully approach her with it. At the right moment, he will deposit the packet and discreetly withdraw. His job is done and he won't live much longer. I suspect, but have no proof, that the reason he is so small is to insure his survival. If he were larger and tastier looking then she might eat him before he was able to mate!

Giant wasps drag off paralyzed victim.
Are you afraid of wasps? I think most people would feel a bit of hesitation confronting a wasp the size of the cicada killer. Don’t worry. They would not sting you unless you tried to handle them, and most people would not try that. I was out working in the garden when I heard a cicada screech in the hickory and then the sound of something hitting the ground nearby. I looked over and was surprised to see a large brightly colored wasp on the ground. Then I saw the cicada that it was holding. The insect was on its back with the wasp on top. The wasp’s stings had done their work and the paralyzed cicada was not moving or making a sound. I ran and got the camera. As I snapped pictures, the wasp dragged the cicada along apparently trying to get airborne with its heavy load. Eventually it managed to haul the paralyzed creature onto the bromeliads that grow up the side of the hickory and from a couple of feet off the ground, the cicada killer was able to launch itself into the air and fly off, slowly gaining altitude, into the oaks at the end of the garden. Once it gets the cicada into its nest, the wasp will lay her eggs on it. When they hatch, the larvae will feed on the still-living cicada. If you want ideas for science fiction stories, you have only to look at the lives of insects. Wasps are our allies in the battle against the bugs. There are over 75,000 species of wasp and nearly all are predators. They feed on or parasitize pest insects and thus help to reduce the loss of crops, trees, ornamentals and other plants each year. Cicadas, for example, lay eggs in slits that they cut in twigs and this can damage fruit trees. When the eggs hatch, the cicada nymphs (immature adults) drop to the ground where they burrow down into the soil and live for several years. The nymphs get their nourishment by sucking the sap from tree roots. Predation by wasps and birds is necessary to keep the insect population from getting out of control. Nature knows how to keep things in balance. It is man who needs to take lessons from the master. If you want to learn more about wasps, read here.
Beautiful bugs kill tomatoes.
These shield bugs on my tomato plants look like emerald jewelry but they have a voracious appetite for ripening tomatoes. Shield bugs are members of the order Hemiptera or true bugs. Their wings are small and not very efficient and the mouth parts are in the form of a beak designed for piercing and sucking plant juices. A few of the 80,000 species are carnivorous. They are also called stink bugs because they have glands that discharge a pungent chemical if the bugs are handled. This chemical warfare is calculated to repulse a potential predator such as a bird. I have smelled the chemical and to me it is not unpleasant, but it is very strong, and a good squirt close to the nose or eyes would probably make a bird think twice about dining on the shield bug. Shield bugs also differ from other insects in their life history. They do not have a larval stage like many insects. Instead, the young bugs--called nymphs--are miniature versions of the adults. they grow by molting the old skin and replacing it with a larger one until they reach adult size. As an organic gardener, I don't use chemical pesticides. The shield bugs in Florida are a particularly tough and persistent breed, however, and there is nothing that will keep them away completely. I have tried spraying plants with blenderized concoctions of garlic, mint, soap and pyrethrum daisy flowers and this keeps them away for a while, but they or some of their cousins always return. I have to share my crop with them, and the plants fed with compost and manure tea will produce enough for both of us. That is the secret for living with the natural world, and I am rewarded by a marvelous variety and diversity of critters that are fascinating to photograph and to watch.
How a moth avoids being dinner.
Can you find the moth in the photo? By masquerading as a dead leaf, this moth may avoid the beaks of the sharp-eyed wrens that cruise around the garden. The wrens love brown moths and I often find the discarded wings where a moth has met its end down a bird's gullet. This moth's color matches that of the leaf exactly, and its wings even have the appearance of veins. The antennae give it away for me but a bird probably wouldn't notice them. So, why haven't all moths evolved this strategy? That is a good question. Many moths do use camouflage to save themselves, and others have large spots on their wings that look like the eyes of a snake or other predator that presumably scares a bird--at least the first time. Evolution is fueled by mutations to the genes and by transfer of DNA, and these changes are mostly random, so the chance that two different moth species would end up looking alike is small. But over a couple of million years of continuous adaptation, species in similar environments can come to resemble each other in one or more ways. This process is called convergent evolution. Insects, birds, bats and even some fish can fly (or at least glide) and they evolved this trait independently. Our current human form is a product of our genes, but the selection pressure came from the environment. The environment of most humans today is hugely different from what it was for our African ancestors a couple million years ago. Yet many if not most of our genes are still similar to theirs. Are we still adapted to our environment or have we changed things around us so quickly that our bodies and minds have not had a chance to keep up? That is a question for you to ponder and maybe to come up with a way to return humans to a better balance with nature.
The goldfinches have not left on their spring migration yet.
Read more at NatureWalks.
Weekend at the beach! See the latest photos from the Florida barrier islands.
Woodpeckers get tired of bugs all the time!
As I was sweeping the stairs this morning, I caught a flicker of movement at the feeder. It was a hairy woodpecker. It flew over to the trellis and began pecking on the branches. Then I noticed the second hairy, and as I watched, the other bird came to it and fed it. Through the binoculars I could see that the one being fed was an adolescent. The colors were duller and the markings less distinct. The parent bird was getting sunflower seeds from the feeder, wedging them in a crack in the branch then pecking off the hull. Once the kernel was free, it would take it and feed the youngster who seemed quite pleased with the situation. The parent bird repeated this several times as I watched. I had seen and heard them several times in the trees near the feeders but didn’t realize that the parents were feeding their young sunflower seeds. The babies peck around on the trees, but they haven't learned how to get seeds on their own. Or maybe they just like being fed! I have watched red-bellied woodpeckers eat sunflower seeds but this is the first time I have seen a hairy woodpecker go to the feeder. You might wonder why a bird would be called 'hairy' when it does not have hair. The bird's ' whiskers' are actually the barbs of feathers without the usual colorful feathery parts. If you looked at a hairy woodpecker up close you would see bristles growing from the base of its beak. Most flycatchers have whiskers also, and so do crows and ravens. What is the purpose of these bird hairs? Bird scientists ( ornithologists) are not sure. They may prevent bits of bark, dirt or small insects from entering the nostrils just as they do in mammals. Or in owls and other night birds they may be sensory tools like the whiskers of cats. So now, when your friends say that woodpeckers only eat bugs and birds don't have whiskers, you can tell them that's not true!
The goldfinches are still here and eating up all the seeds!
The finches are still here and gobbling up sunflower seeds like there’s no tomorrow. I’m surprised they can still fly! And speaking of flying, when are they going to leave? Finches are migratory and don’t breed in Florida. They do have a pretty wide range, however. According to Sibley’s Field Guide to Birds of Eastern North America, the American goldfinch is a winter resident in Florida, but a summer resident in Canada and the northern U.S. Between these two regions they can be found all year long. Most of our goldfinches have left and the ones I see may be coming up from south Florida and stopping over to replenish their fat before continuing the journey north. I wonder if they remember these rest stops from year to year and come back to the same feeders. It pleases me to think that there’s a flock of goldfinches out there with a little image of my yard imprinted on their visual cortex, or wherever visual memories are stored in birds. How they would navigate to the exact spot, however, is hard to imagine unless they have the equivalent of a GPS hard-wired into their brains. Maybe they keep a memory of the entire route and look for landmarks that guide them to various goldfinch restaurants along the way. What we don’t know about bird behavior would fill volumes. I’m curious about what triggers them to leave in the spring, but I also look forward to the first goldfinches to arrive each winter. Their familiar twittering and lemon color uplifts the spirit and brings a comforting sense of continuity and oneness with nature. Their departure will be followed by the seasonal appearance of other creatures, swallowtail butterflies, fireflies and dragonflies to name but a few. So what’s the take home lesson, here? Create a habitat for birds and mammals, reptiles and insects around your home and you will never lack for colorful, interesting friends to share the changing seasons with.
Come join us for a weekend of sun and sand and fun!
The Florida barrier islands are a wonderful place to enjoy the seashore away from the crowds. Some are accessible only by boat and these are the best for seeing birds and sea turtles. We spent a three-day weekend there the first week in April and it was wonderful!
The beaches here are wide and the sand is perfectly white. The water is a clear crystalline blue. Seabirds like the islands because there are fewer humans around and the fishing is good. Flocks of terns and skimmers gather on the sand all facing into the wind. Willets in pairs and gaggles of sandpipers and dowitchers cruise along the water line looking for small crustaceans.
In the air you will always see ospreys and hear their plaintive whistles as they call to one another. I also saw the wonderful frigate birds with their knife-like wings and ability to soar and glide on the thermals without flapping their wings. Here, like the ospreys, they are fishing and they drop out of the air in a powerdive with wings folded arrowing into the water and nearly always emerge with a fish. Pelicans use the same plummet and grab strategy. The ospreys, however, do not seem so keen on getting wet. They do their fishing by swooping down and grabbing the victim in their talons on the fly.
	There are several large osprey nests on the island and they are used year after year. There are two chicks in this nest but they refused to pose. It is wonderful to share the habitat with wildlife and be able to watch them going about their lives without human interference.