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BACKYARD SECRET: BLUEBIRDS EAT MONARCH CATERPILLARS

       Most of us have been taught that birds do not eat monarchs.  In fact, if a bird just happens to try to make a meal out of a monarch, it gets sick from ingesting the poisonous compounds that course through the monarch’s body.  After living through such an experience most birds do not try to dine on a monarch again. 

       Eastern bluebirds are an exception to the rule.  These gorgeous backyard favorites eat monarch caterpillars laden with poisonous chemicals obtained when they chomp on milkweed plants without showing any ill effects.  

       The bluebird can devour this toxic food because it uses a technique to prepare a caterpillar before it tries to consume it.  Once a bluebird grabs a monarch caterpillar it flies to a branch and squeezes the large, juicy caterpillar time and time again.  This process forces much of the juicy innards of the caterpillar out both ends of its body.  Once the caterpillar has been flattened, the hungry bluebird then proceeds to eat the hapless insect.

 

 

THE WIND CAN HELP MONARCHS MIGRATE

       Now that September has arrived it is hard not to turn our thoughts toward fall and migration.  Invariably we associate migration with birds.  However, the plight of the monarch has heightened our interest in the migration of insects such as the monarch butterfly. 

       Each fall these amazing insects make their way south to their winter home in Mexico.  While this is truly an amazing fete, we know very little about how these butterflies accomplish this seemingly impossible task.  Recently the results of research conducted by Samantha Knight of the Nature Conservancy of Canada and others filled in another piece of the jigsaw puzzle of monarch migration.

       The research team captured and placed tiny transmitters weighing only 300 milligrams on 43 monarch captured near the Canadian shore of Lake Huron.  The devices were mounted on the insects in an attempt to track their southbound migration.         Fortunately, the biologists were able to retrieve data from six of these butterflies.  One of the most interesting findings was one of the monarchs flew 89 miles in a single day.  They were also able to determine the monarchs winged their way south at a speed on 7.5 miles per hour.  Knight later stated, “[It] was a lot faster than anyone had ever really anticipated.”  She went on to comment, “They could likely go even faster without the heavy tags on them.”

       The biologists also learned the butterflies flew faster when they were pushed along by a tailwind.  This was demonstrated by one butterfly that was clocked flying at a bit under 18.5 miles per hour with the aid of a tailwind.

      It was also discovered that monarchs flew faster in warm weather.  However, the butterflies were not able to fly until the temperature reached 50˚F and flight speed dropped when the air temperature reached 73˚F.

       It is definitely true the more we learn about these stunning insects the more we realize why they are so special.

GREAT GEORGIA POLLINATOR CENSUS

       Some of our most fascinating and important backyard wildlife neighbors are pollinating insects.  Unfortunately, populations of many of these critters are declining. In an effort of assess the number of these pollinators across the state, the University of Georgia’s Cooperative Extension is conducting the first Georgia statewide pollinator census.  The count will be held August 23 and 24, 2019.

       Becky Griffin, UGA Extension school garden and pollinator census coordinator is inviting private citizens, families, clubs, school classes and other groups to cooperate. 

       The count is fashioned after the highly successful Great Backyard Bird Count.  Consequently, whereas you do not have to be an expert in bird identification take part in the Great Backyard Bird Count, you don’t have to be able to identify the insect pollinators that visit your garden.  Participants are simply asked to separate pollinators into eight groups (carpenter bees, bumble bees, honey bees, small bees, wasps, flies, butterflies/moths, and other insects.  An easy to understand online guide to these insects can be downloaded from the Great Georgia Pollinator Census website (GGaPC.org).

       Here is what you need to do to participate:

  • Visit the Great Georgia Pollinator Census website and download the GGPC Observation Sheet. The sheet can be used to record your sightings.
  • Select a single plant growing in your yard that you know attracts pollinators.
  • Count the pollinators landing on the plant during a 15-minute period.
  • Visit the website once more and upload the results of your count.

       I sincerely hope that you become citizen scientist and participate in the state’s first-of-its-kind pollinator count.  If you do, you will be helping conserve these valuable insects.

       If you have any questions regarding the census, contact mailto:Becky Griffin at beckygri@uga.edu.

SOUTHERN BEE KILLERS LOOK LIKE BUMBLEBEES

      The next time you spot what appears to be a bumblebee perched on a plant in your garden, take a close look at the insect, as it just may be accomplish insect predator known as the southern bee killer (Mallophora orcina)

       The southern bee killer is one of the approximately 1,000 species of robber flies that inhabit North America.  All of these amazing flies eat all sorts of insects; however, the southern bee killer prefers to eat paper wasps, carpenter bees, honeybees, and bumblebees.

       The southern bee killer is commonly inhabits backyards throughout the entire state.  In spite of this, unless you actually spot this predatory insect flying about with its prey, chances are you mistook it for a bumblebee. Bumblebees do not fly about clutching other insects.  That is understandable as it is fuzzy like a bumblebee, and its body is marked with the yellow and black pattern we associate with bumblebees.  In addition, if its legs seem to be exceptionally long and its eyes extremely large, you are probably looking at a bee killer.

       The southern bee killer is a true mimic.  It definitely looks like a bumblebee.  Biologists are not certain how the bee killer’s similarity to a bumblebee benefits the insect.  Some suggest it causes predators that do not like to be stung by bumblebees to shy away.  Who knows?

       At any rate, the southern bee killer is an ambush predator. It spends its day perched on a blade of grass, flower, twig, or other object and waits from a bee to fly by.  Once it spots a potential prey, it immediately chases it down.  If successful, it grabs the hapless bee in midair and impales it with its powerful, sharp mouthparts.  It then immediately injects its prey with a combination of enzymes and nerve poisons.  This deadly concoction disables the insect and dissolves its body tissues.  The bee killer then drinks its liquefied meal. 

       Since bee killers routinely return to the same perch, if you happen to locate a perch, check out this location from time to time, you can watch the bee killer hunt time after time.

       Although the southern bee killer is a deadly predator, I have never heard of an instance where one attacked a human.  That being said, if for some reason you happen to touch one, it can inflict a painful bite.

        

BACKYARD SECRET: SUNFLOWERS HELP THWART BEE DECLINES

       The demise of bee populations across the country is a major concern.  The economic and ecological impact of declining populations of these pollinators is staggering.  For years, scientists have been diligently trying to determine both the causes and solutions to this problem.  The findings of a study recently published in Scientific Reports suggest the sunflower may provide a glimmer of hope for some species of bees.

        The study investigated the possible impacts of diets of two species of bees containing various pollens on populations of two of the parasites linked to high bee mortality and sluggish colony growth.  The study reported European honeybees and common bumblebees that fed on the pollen produced in the flowers of sunflower plants were less infected with these parasites than bees that did not consume sunflower pollen.

        In the words of Rebecca Irwin (one of the biologists that conducted the study), “We tried other monofloral pollens, but we seem to have hit the jackpot with sunflower pollen.”

        Although this discovery is promising, the biologists that conducted the study were quick to point that, since sunflower pollen is low in both protein and some amino acids, the bees cannot live on sunflower pollen alone.  As such, they need to supplement their diets with the pollen of a variety of other pollen-producing plants.

        Consequently, if we homeowners want to help in the fight to thwart the ravages brought about by two of the deadly parasites that plague our bee populations, we need to add sunflowers to the variety of other pollen- rich plants growing in our backyard.  I am please to say sunflowers are currently blooming in my backyard.  I hope you will find a place for them in your backyard too.

BACKYARD SECRET: THE CATERPILLAR’S AMAZING GROWTH RATE

Some caterpillars exhibit an unbelievable growth rate.  Believe it or not, the caterpillars of some butterflies actually double their weight every two days.  If a human baby had a similar rate of growth, it would weigh a ton in just 14 days!

MEET THE RED ADMIRAL

        The red admiral is one of our most recognizable butterflies.  This is because this dark, medium-sized (1.75-2.50″) butterfly displays striking reddish orange bands across the tops of its wings.

        The red admiral flies rapidly from spot to spot.  It often lands on the ground, the sides of our homes, large flowers, you name it.  There it will often flatten out its wings and bask in the sunlight.

        Whenever it lands on a flower, do not assume it is nectaring.  The red admiral is a butterfly that only occasionally seeks nectar from blossoms.  Instead is prefers to dine on the sugar found in plant sap.  In fact, the largest concentration of red admirals I have ever seen was feeding on a gaping wound on the trunk of a willow tree.  Sap was oozing from the spot where a large limb broke off the tree the night before during an intense thunderstorm.         

        The butterfly will also dine on the juices oozing from rotting fruit.  I have also encountered red admirals seeking nourishment from dry dog food.  In addition, to the chagrin of many, it will also visit piles of dung. 

        The list of red admiral host plants includes pellitory, nettles, and false nettle.

        Since red admirals are now flying about backyards throughout Middle Georgia, I am sure they can now be seen in other parts of the state too.  If you have not seen one yet, you have plenty of time to make the acquaintance of this butterfly this year.  This strong flyer can be seen in Georgia from March through early November.

        I must admit I do not see as many red admirals as I would like, however, whenever I do spot one it is a special treat.  If you encounter your first red admiral this year, I am sure you will understand why I am so fond of this butterfly.

DRAGONFLIES ARE SHOWING UP IN BACKYARDS

        Dragonflies are beginning to make their appearance in our backyards.  These aerial predators are on the prowl looking for mosquitoes and other small insects.

        The first species to show up in my backyard this spring was the common whitetail (Plathemis lydia).  The male of the species (depicted here) is not difficult to identify.  Its body varies from white to pale blue.  This dragonfly’s eyes are brown.  The insect’s clear wings are marked with wide bands about halfway between the tips of its wings and body.  The leading edge of this bands display slender streaks that project toward the tip of the wings.  The insect measures roughly 1.5 – 1.9 inches in length. 

        The bodies of immatures and females are brown and marked with white lateral stripes.  The wings of immature males resemble those of adult males.  In comparison, one of the main differences between the pattern of the female’s wings and those of the adult male is they are tipped in brown and black.  Since immatures and females are sometimes tricky to separate from other similar species, it is always best to consult a field guide when trying to identify them.

        It is possible to see common whitetails in yards across the state, however, chances are best if you live near water.

        Here in the Peach State common whitetails fly from March into early November.            

MONARCHS ARE STILL PASSING THROUGH GEORGIA

After what seemed like an endless series of rainy/misty days during which the temperature hovered in the 40s and low 50s, I was convinced I would not see another monarch this year.  However, much to my surprise after the rain finally moved out, and the nighttime temperature plummeted to 31˚F, I was surprised to see a monarch nectaring at the blossoms on a butterfly  bush in my backyard this morning (November 16).  When I saw the butterfly, the air temperature was 51˚F. 

       Later on in the day, I spotted a gulf fritillary nectaring at the same bush.

       If that wasn’t enough, shortly thereafter I spotted a cloudless sulphur fluttering at the windows in my sunroom.  The butterfly was obviously roosting on one of the plants my wife and I moved inside the night before.

       My experiences on this chilly November morning galvanized my long-held belief that my backyard wildlife neighbors will never cease to amaze me.  As such when I walk outside each morning, I expect the unexpected.

YELLOW JACKETS SEEM MORE PRONE TO STING IN FALL

       Throughout most of the year, it seems that we have a truce with yellow jackets.  For the most part, these small, yellow, and black wasps will not attack unless we antagonize them in some way or just happen to venture too close to their nests.  However, have you ever wondered why, from late summer into fall, folks seem to be stung more often by yellow jackets than at any other time of the year?  If so, read on. 

       There are a few plausible reasons why the chances of being stung by yellow jackets increases as the days are cooler the foliage transforms from green into a kaleidoscope of color.

       Entomologists tell us yellow jackets are simply more abundant in autumn.  At this time of the year, a yellow jacket nest may contain upwards of 800 individuals.  Faced with this overcrowding, the members of the colony become less tolerant of one another as well as humans and other animals alike.

       Some biologists suggest this behavioral change may also be linked to the insect’s switch from a predominantly protein diet to one rich in carbohydrates.

       Realizing these insects are more apt to sting without provocation at this time of year, we all need to use caution when changing the nectar in our hummingbird feeders or working about our yards.         

       This threat will slowly diminish as the sterile female workers begin dying with the approach of winter.  Interestingly, the only yellow jackets that survive the winter are the queen.