Thursday, January 27, 2011

Black Field Cricket

One of the most common sounds of autumn is the call of the cricket in the family Gryllidae. These are known as the true crickets. The persistent chirping that these insects make drones on and on for what seems like an eternity; for some it is a sound that is almost musical. Their outdoor experience would not be complete without this beautiful chorus. For me however the sound these little ebony colored musicians play is akin to the sound of fingernails on a chalkboard. It is a brain piercing noise that makes my eyes twitch. So whether you love them or hate them one thing is for certain they are sure to be back each year.

The field cricket is a cold-blooded creature, just like all insects. They will take on the temperature of their surroundings. In essence what this means for the cricket is; the warmer the outside temperature, the faster and more energetic the he will sing. So in contrast when the temperature outside drops his chirping will slow down. Why do crickets sing in the first place? There are several reasons for all the noise. They advertise their presence to other males and chirp to warn them away, in theory it works like a no-trespassing sign “Keep out.” They also sing happily when they locate a particularly tasty food source. The most important reason for their singing is to attract nearby females with which to mate. With so many kinds of crickets out there how do they find each other? Each species has its own distinct call and females of their own kind can home in on the male’s song and locate the would-be suitor. How are they able to hear each other? They have special membranes located behind the middle-joint of each front leg, so essentially they have ears on their knees.

Mating takes place in the late summer or early fall. Females will use a long apparatus at the end of their abdomen called an ovipositor to inject, or deposit eggs within the soil. The eggs will stay protected within the soil all winter and hatch the following spring. The young nymphs are born looking very much like their adult counterparts, minus wings. As they feed and grow they will attain wings and reach their adult size by mid-summer. Crickets are omnivores and feed on a wide variety of foods including organic materials, decaying plant materials, fungi, and some seedling plants. Crickets will even eat their own deceased and weakened kind when there is no other food source available to them.

Crickets do have powerful mandibles (jaws) and can inflict painful bites, although these bites rarely break the skin. They are considered harmless to humans, as they do not spread any diseases or contaminate our foods. They can however be a nuisance, when they enter our homes. Sometimes they make it into our basements or worse yet our bedrooms. When one of these noisy creatures ends up in our bedroom I am up and out of the bed like a shot tearing apart the bedroom until I locate the trouble maker, all the while my husband is giving me the one-eyed, sleepy, what the heck are you doing look! I cannot sleep with one of these creatures chirping, I literally feel my eyeballs twitching with every chirp. To complicate matters, turning on the light to try and find it only makes the bug shut-up. Turn the light off, climb back into bed and it starts up again! GRRRR! After what seems like hours I finally track down the culprit and throw him outside (resisting the urge throw him in the toilet). There really isn’t any full proof way to keep them out of your house short of spraying chemicals along foundations to try and prevent them from coming in. Once the temperatures drop to freezing the crickets will die and it is up to eggs in the soil to carry on the next generation.

Crickets are found throughout history depicted in many cultures throughout the World. In China they are popular pets and are considered good luck. They are often kept in cages. In Mexico and Southeast Asia they are also used as a gambling or sports betting pastime. They are even considered a delicacy in Mexico and are consumed as part of their diet. In Brazil the singing of the cricket signals impending rain, or a financial windfall. In other parts of Brazil a black cricket in a room is said to predict illness within the household; gray one means money; and a green one signals hope. Still in other areas of Brazil they are killed immediately because of their association with death. In the United States cricket chirping is often used when a comedian tells a joke and it flops. Instead of laughter or clapping you hear the sound of chirping crickets. Walt Disney made one cricket very famous; Jiminy Cricket played the part of Pinocchio’s conscience, and continues to be the most recognized off all cartoon insects.

Crickets are nocturnal, and therefore typically only heard close to sundown and throughout the night. During the day they hide out under rocks, rotting wood, or in dense vegetation. It seems that their populations vary year to year. Some years they seem to be everywhere we look, and other years their numbers are small by comparison. These crashing populations could be victims of severe winter temperatures and ground freezing. They could also be victims of predation as there are many ground dwelling insect larvae that feed on the eggs of crickets. In years when these predators are more abundant then the cricket populations are sure to suffer as a result. Then the following year after a majority of the crickets have been consumed, the predator’s population will dwindle and the crickets rebound.

So while these noisy little creatures can be a nuisance and drive many of us crazy with their insistent singing, I have to admit being outside would not carry with it the same attraction without them. Sitting outside near a campfire, fishing and enjoying a starry night is made all the more special by the chorus of crickets in the background.

Saturday, January 15, 2011

Batty for Bugs...or...Buggy for Bats

 Bats are mammals, and certainly not an arthropod, but I figured since they feed on numerous insects it would be okay to feature a couple of bats that came into my possession this past week. They have long been one of my favorite creatures. I've put up bat houses to encourage them to take up residence on our farm. So far they have not used the houses, but I do see bats feeding on the insects at the pole lights.

This face that only a mother could love belongs to an Evening Bat (Nycticeius humeralis) and it showed up in a persons house in St. Joseph. Animal Control was called and rescued the bat. I received a phone call asking me if I would take it and find a safe place to release it. It is very difficult in the winter to rescue these little guys. Releasing them outside is obviously out of the question and not just any location will meet their requirements. The area must be cold in order to encourage hibernation, yet not too cold to freeze them to death. It cannot be too warm or it will encourage them to awaken and fly around. This activity will cause them to use up valuable fat stores and may result in them being unable to survive the rest of the winter. Fortunately on our farm we have such a location in the form of an old farrowing house. It is a large building with a peaked ceiling. We have a small amount of heat in the building to keep water lines from freezing. You can still see your breathe in the building. So I captured a few quick images of this little beauty and then quickly placed it in the farrowing house.

Evening bats are very common in the Southern half of the United States, and are often found with Big Brown Bats and Brazilian Free-Tail Bats. They very much resemble Big Brown Bats and are often mistaken for them. Evening Bats are smaller, uniformly dark brown in color, and have black ears, wings and tail membrane. Their nose lacks fur. They measure up to 3.5 inches in length and have a wingspan up to 11 inches. They weigh up to 1/2 ounce.  In the northern part of their range they are less common and will migrate to hibernation locations. Sometimes they travel great distances to reach these winter roosting sights. In Missouri they seem to use attics and other locations to spend the winter.This species is often seen roosting in towns and rural areas. Males will form harems and defend their females from other male Evening Bats. Females give birth to one or two pups. Occasionally three pups may be born. They seem to suffer separation anxiety from their mothers and are very vocal when their mothers are out of their sight. The young are ready to leave and fly at 20 days. In autumn the young males are cast out of the colony and may show up in odd places like the eaves of houses or outdoor stairwells.

 Large colonies (up to several hundred individuals) will be found roosting together in old buildings. Smaller colonies (up to 40 individuals) will roost under the loose bark of trees where they squeeze close together to accommodate the tight quarters. In early spring they come out of hibernation and begin foraging for insects early of an evening. They feed on beetles, leafhoppers, flies, moths and ants. Evening Bats are important predators of the Spotted Cucumber Beetle, making them a friend to farmers and gardeners alike. These particular bats often find themselves prey to feral cats and many are sacrificed to hungry wild kitties all over the southern states.

This tiny little bat is a Little Brown Bat (Myotis lucifugus). This species is a member of the "Mouse Eared Bats (myotis) and were at one time the most common bat found in their range. There are reports however that claim their numbers are declining and they are becoming more difficult to find in the populations that they previously occurred. No one seems to know how or why this is. Is it a disease? Are they victims of predation? Is it loss of habitat and suitable roosting sights? Hopefully research will bring about the answers before their numbers fall too dramatically. This one too showed up in a persons house and needed rescuing. The gentleman at Animal Control wanted to know why bats were suddenly showing up in peoples homes, especially now during the coldest spell we've had so far this winter. I told him it could be one of several reasons. First being the actual cold that should keep them sleeping. It seems that at 30 degrees or warmer they rest contentedly. When the temperature drops another 30 degrees like it has this past week they become aggitated and begin  looking for warmer environs. This often leads to them finding their way into the living quarters of whatever dwelling they are roosting in. Second reason could be a disturbance of some kind. Perhaps loud noises or unusual activity awoke them and roused them out of their winters sleep. This too would result in them flying around and becoming disoriented and ending up in your house. Too many disturbances is dangerous for them. It is imperative they return to slumber quickly and with as little fuss as possible.

The Little Brown Bat species is very small at 2.4 -4.0 inches in length and a wingspan up to 11 inches. They weigh a mere 1/2 ounce. They have shiny pale brown to dark brown fur. Their coat is evenly covered, and the hairs on their toes extend to cover the toenails. This is a long lived species and may live up to 34 years, with males living longer than females.

Little Brown Bats roost in hot attics during the summer in colonies they may number up to 1,000 members. They will roost in bat houses and other man made structures in smaller numbers. They will even use dead or decaying trees as roosts. Their roosts will generally be located near water. They mate in the fall and the females will store sperm until the following spring. This ability to delay fertilization assures the pups won't be born while the mothers are hibernating.  The female will give birth to one pup sometime in May, June or July. They are born furless, and with their eyes closed. They will rest under their mothers wings during the day, then at night the mothers leave them in the roost so they can go out and forage for insects. They typically eat mayflies, crane flies, moths, gnats and beetles. They are capable of eating their entire body weight in insects in a single night.  Most hunting grounds are located near water, like ponds. They capture several hundred mosquito sized insects in a single hour. Pups are able to fly at 2 weeks of age, and will be adult sized in approximately 20 days. When fall returns they will seek their winter hibernation spots that may contain up to 300,000 individuals.

There are fourteen species of bats living in Missouri and each of them are insect eaters. We do not have vampire bats or fruit bats in Missouri. Therefore all Missouri bats are helpful to us by controlling insect populations. It has often been said that they eat thousands of mosquitoes in a single evening. While it is true that they are capable of eating mosquitoes, they however prefer larger prey insects like moths. The larger the insect the more energy and calories gained. It is kind of like showing up at a buffet and choosing to eat a salad. Does any of us really do that? Nah, of course not.....

 Bats do however carry rabies, and this is a very real threat. Approximately 40 cases are reported annually in Missouri of bats that test positive for rabies. Considering there are millions of bats living in Missouri this is a relatively low number. There are about 1/2 of 1 percent of bats that carry the virus. Bites typically occur when people find a bat out during the day and handle the bat, or they handle one that mistakenly makes its way into your home. Never under any circumstances handle a bat that is out during daylight hours, instead call your local Animal Control Center. If one makes it into your home, use caution and never try to handle one without sufficient gloves. It is best to call Animal Control.

Our local Animal Control has me on their call list to take bats for release and rehab. I have completed training through a licensed Wildlife rehabilitation Center and have my name listed with the Missouri Department of Conservation.

There is no reason to live in fear of bats, they are one of the cleanest animals in existence. They spend a huge amount of time grooming themselves. The chance of rabies infection is low, and they provide valuable insect control. Lastly they are just plain cool!!!!

Wednesday, January 12, 2011

Fruit Flies

There are two families of fruit flies, Tephritidae (pictured here) and Drosophilidae. Fruit flies in the family Tephritidae are large, colorful flies with elaborate wing markings and are sometimes referred to as Peacock Flies. There are over 5,000 species of fruit flies in 500 genera. Therefore there is no shortage of specimens to study. Many fruit flies cause significant damage to agricultural crops, especially fruit trees. One species Bactrocera oleae targets Olive Trees and when they invade an olive grove they have the potential to destroy the entire crop production. Most of the species that wreck havoc on crops are within this genus (Bactrocera).

Females lay their eggs in the plant tissue of a wide variety of plants, when the eggs hatch the young maggots begin feeding on the soft tissue of the plants. In large numbers these flies can cause substantial financial loss for agricultural producers. Other species are considered beneficial because of the preference for preying on other species that are causing the damage. Most of these flies have very short lifespans and only live up to one week or less.

I find these flies occasionally near our garden, and they are most likely after the veggies growing there. We have never found them in large numbers, generally just a few once in awhile. I think they are one of the most beautiful flies I've ever seen. They are exceedingly difficult to photograph and be able to do all those brilliant colors justice.

Then there are the pesky little fruit flies in the family Drosophilidae, these are the tiny little flies that magically appear in our fruit bowls. It doesn't seem to matter if the fruit is fresh or on its way to the compost bin, they are there flying around, landing on the fruit, hovering near our eyes. Where do they come from? Are the eggs in the fruit when we purchase it? Are they hiding out in our homes just waiting for the tempting aroma of fruit to appear? It really is a mystery, and one that I have never been able to solve. We've always called them gnats because of the diminutive size. They are dark in color and have bright red eyes. Because of their tiny size seeing these fine details can be difficult.

 (internet image)

For all their annoyances, these are really one of the most beneficial flies that exist, to science at least. These flies have long been studied in laboratories all over the world. They are easily kept and only require small containers to be kept in, and a little water. They complete their lifecycle in about 10 days making research much more rapid. Then there is the added advantage that very few if any people will object to scientific studies being done to a mere insect. About 75% of known human diseases have genome matches in the common laboratory fruit fly. This makes them significantly helpful in solving many of the mysteries surrounding common and maybe not so common diseases that plaque mankind. They are being used as a marker in the study of Parkinson's, Huntington's, Alzheimer's, diabetes and many forms cancer just to name a few.

Next time we swat at those pesky fruit flies perhaps we should gives thanks for the all the good they do for us.....and just maybe we should consider it is worth losing a little fruit....

Monday, January 10, 2011

Eight-Spotted Tumbling Flower Beetle

This wedge shaped little bug is the Eight-Spotted Tumbling Flower Beetle (Hoshihananomia octopunctata) and they are found throughout Eastern North America. They are easily overlooked because of their diminutive size and at just 1/4 of an inch in length it is easy to see why. The wings and thorax are dark with distinct yellow markings. The head is flattened and wide and the abdomen comes to a point. They are found most anywhere flowers are found including gardens, meadows, prairies along roadsides and open fields. The adults eat pollen and nectar especially that of Queen Anne's Lace and the larvae apparently eat the plant material on which they are reared. Very little is reported on their lifecycle, although it is known that the female will lay her eggs on or near decaying pithy wood of hardwood trees. The resulting offspring feed on this decayed wood or on the fungus associated with the dying tree.

(Photo by: Steve Scott)

These beetles get their common name from their habit of "tumbling" off flowers and feigning death when disturbed.