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SURPRISED TO SEE A MONARCH ON A FROSTY MORNING

Nov10

         Today I awoke to a thermometer reading of 32˚F. This marks the first day the temperature has plummeted to the freezing mark this fall.  While I do not have any idea how long the temperature hovered this low, I know it could not have been too long since none of the plants flowering in my backyard showed any signs of frost damage.

When I ventured outside for the first time on this sunny, cool day the temperature had risen to 57˚.  Much to my surprise the first creature I saw this morning was a monarch butterfly.  The monarch was nectaring on the purple blossoms displayed on two butterfly bushes.

Needless to say, I was startled to see a monarch on such a cold morning since even on a sunny day, monarchs are rarely seen when the air temperature is in the 50s.  When it is cloudy, this magnificent butterfly often does not take to the air until the air temperature reaches 60˚.  That being the case how was this butterfly out and about feeding?

More than likely it must have spent the night roosting nearby in a location where the temperature remained above freezing.

In autumn, when monarchs are passing through the south on their way to Mexico they seem to prefer to roost in pecan and oak trees; especially those growing close to a nearby source of nectar. These trees offer protection from the wind and their dense foliage provide places to roost that at are often warmer than the air temperature.

During the past few years, I have noticed that late in the afternoon during the monarch migration, monarchs will nectar on one particular butterfly bush growing on the north side of my home.  Just beyond my driveway stand three water oaks.  Several times as the sunlight melted away, the monarchs would flutter up into the oaks and vanish from sight.  While I am not positive this is their nighttime roost, I suspect it is.

Wherever the monarch I saw this morning roosted, it could not move until the temperature rose above 40˚.  As the temperature slowly climbed, the butterfly had to crawl to a sunny spot and open its wings and bask in the warming rays of the sun.  The butterfly’s black scales and abdomen enabled to it to absorb the heat needed to raise its body temperature.  Once its flight muscles reached 55˚ degrees, the monarch was capable of flight.

I am certain the monarch I saw this morning is now miles away from my backyard.  As the sun begins to dip below the horizon this afternoon, I hope it finds another suitable roost site and the night will not be as chilly as it was last night in Monroe County.

FEMALE MONARCHS ARE BETTER FLIERS THAN MALES

Oct27

      One event that backyard wildlife enthusiasts look forward to each autumn is the migration of the monarch butterfly. During the fall of the year, these beautiful butterflies stop and feed in our backyards as they make their way to their winter home in Mexico. This epic flight takes a tremendous toll on these gossamer-winged insects.

       Ever since it became apparent monarch populations have plummeted to a fraction of what they once were, researchers have been scrambling to learn as much as they can about this fascinating insect. The results of one such study recently conducted by University of Georgia, Odum School of Ecology researchers provide us with answers as to why female monarchs are better fliers.

       When the UGA research team compared the wings of male and female monarchs, they discovered some notable differences. It seems the females’ wings are thicker, and somewhat smaller. In addition, their flight muscles are smaller and lighter.

       One might think having larger and heavier wing muscles, coupled with thinner and lighter wings would benefit the males. Actually, the reverse is true. The males’ larger and thinner wings are more susceptible to damage. Their wings also forced to bear more weight per square inch than those of the females.

       In essence, this means female monarchs are more efficient fliers than males. This, in turn, enhances the chances of the females surviving the autumn migration.

QUESTIONS CONCERNING CREPE MYRTLE

Oct20

       When I posted a blog concerning the value of crepe myrtle to wildlife, a blogger posed her concern that I had wrongfully maligned this popular ornamental, and wondered what the basis of my opinion was.

       It seems when crepe myrtle is blooming in her yard bees converge on the plant’s colorful flowers. She went on the say that when she deadheads the first crop of blooms to encourage a second blooming, when a new crop of blossoms bursts forth the bees return to once again feast.

       To say the least, I was surprised to learn that the bees in her backyard are drawn to crepe myrtle blossoms in large numbers. The crepe myrtles that grow in my neck of the woods are rarely visited by bees. This could be explained by the fact that she grows varieties such as Lipan, Tuscarora, and Dynamite. I am not familiar with them; they may produce an abundance of pollen and/or nectar. I do not know the name of the crepe myrtle rooted in my yard; however, I am sure it does not produce much of value to pollinators. I have seen wild pollinators feeding on the honeydew secreted by the aphids that live on the plants.

       I should also mention I have seen American goldfinches eat crepe myrtle seeds.

       In addition to producing little food, crepe myrtle is an exotic plant is invasive in many sections of Georgia. When it “walks away” from the place where it is planted, it can usurp habitat originally occupied by native plants. Typically, the native plants it supplants are of more value to wildlife than exotics.

       I am not the only wildlife biologist that does not consider crepe myrtle to be a great wildlife plant. Here is what Dr. Doug Tallamy, professor and chair of the University of Delaware’s Department of Entomology and Wildlife Ecology, has to say about crepe myrtle, “Crepe myrtle is an enormously popular landscape plant because it has a nice habit, beautiful flowers, and lovely bark. But it contribute almost nothing to the food webs in your garden. If every plant is your yard were a crepe myrtle, you would have no food webs, and, thus, no birds, butterflies or other beneficial wildlife”

       If you enjoy the beauty offered by crepe myrtles in your yard, and the varieties you plant provide bees and other wildlife with food, continue to cultivate them. Meanwhile, plant some native plants that evolved alongside the native pollinators and other wildlife in your area. If you do, I think you will find they will be of great value to your backyard wildlife neighbors. In addition, you will be contributing to restoring the natural ecology of your yard.

LONG-TAILED SKIPPERS HAVE TAKEN CENTER STAGE IN MY BACKYARD

Oct6

        The long-tailed skipper is a butterfly that can be seen in all of Georgia’s 159 counties.  Although it can be seen from April into November throughout much of the state, in my backyard, I see more long-tailed skippers from late summer into the autumn than at any other time of the year.  Since it is so common and seen over such an extended period, one might think all of these butterflies live and die in the Peach State.  Actually, many do.  However, some have wanderlust. 

       For reasons that are not fully understood, during the summer some long-tailed skippers take wing and move northward.  These movements are particularly common along the Coastal Plain.  As a result, before cold weather sets in long-tailed skippers are sometimes spotted as far north as southern New England.

       Far more often, however, each fall far more long-tailed skippers will fly south to the peninsula of Florida.  Here in Georgia some longtails are considered permanent residents, particularly in the southeast corner of the state.

       In spring, long-tailed skipper populations in Florida begin moving northward and eventually end up in our backyard gardens.

       I suspect many of the long-tailed skippers I am currently seeing in my backyard are en route to the Sunshine State.  Meanwhile, for the past several weeks, long-tailed skippers are the butterflies I have most often seen visiting ageratum, butterfly bush, zinnias and other fall-blooming plants.  This is the first autumn I can remember when I have seen more long-tailed skippers than cloudless sulphurs in my yard.  I suspect our prolonged drought has played a role in this situation.

       In the meantime, since I am not seeing any migratory songbirds in my yard, and most other butterflies such as eastern tiger swallowtails have disappeared; long-tailed skippers have added an appreciated touch of beauty to a backyard that has suffered immensely from a lack of rainfall.

BACKYARD SECRET: BLUEBIRDS EAT MONARCH CATERPILLARS

Sep4

       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

Sep1

       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

Aug11

       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

Jul14

      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

Jun19

       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

Jun13

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!