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EASTERN TIGER SWALLOWTAILS CAN BE YELLOW OR BLACK

        Believe it or not, one of our most misidentified butterflies is the eastern tiger swallowtail.  This might come as a surprise to you since it is our state butterfly and is one of the largest butterflies that visits our yards.  This reason for this is this gorgeous butterfly has two color phases.

       The wings of the males are predominantly yellow and marked with vertical stripes.  This is the color form most people recognize.  Females, on the other hand come in either yellow or black phases.  If you look closely at the wings of a dark female, you will usually seen telltale black stripes.  The black form of the eastern swallowtail is the phase many people do not realize is also an eastern tiger swallowtail.

       In middle Georgia, my neck of the woods, more than 90 percent of all female eastern tiger swallowtails are black.  However, dark females are far less common in some other parts of the country.  Some lepidopterists – folks that study butterflies – suggest that the percentage of dark females is greatest where pipevine swallowtails are most abundant.  For example, black females are far less common in New England and others parts of the butterfly’s range.

       Interestingly, dark females are prone to produce dark daughters while yellow females usually have yellow mothers.

      Dark females have a better chance of surviving long enough to lay eggs than yellow females.  The reason why is that dark females look much like the poisonous pipevine swallowtail.  The pipevine has an extremely bitter taste.  If bird or other predator tries to eat one, it rarely goes back for seconds or even attacks a butterfly that looks like it.

       I would be interested in know the percentage of black females to yellow females you see in your yard.  If you conduct a survey of the eastern tiger swallowtails in your yards, let me know what you find.

BACKYARD SECRET: GRAY SQUIRRELS HAVE A UNIQUE WAY TO SHADE THEMSELVES FROM THE HOT SUN

          The gray squirrel uses its tail to help to help balance itself as it climbs and jumps from limb to limb, an even break its fall when is tumbles from a limb high above the ground.  Unbelievably on bright sunny days, the gray squirrel flips its bushy tail over its back and utilizes it as a parasol to keep the rays of the sun from overheating its body.

PANTING HELPS BACKYARD BIRDS KEEP COOL

          During the current heat wave, when we step outside into our   backyards one might think we have entered Sonora Desert.  With daily temperatures hovering in the 90s and heat indexes soaring well above 100˚F, trying to keep cool is next to impossible.  While it is difficult for us to keep cool in this oppressive heat, rest assured it also tough for our bird neighbors.

          One way in which our bodies try to keep us cool is by sweating.  When perspiration builds up on our skin and evaporates into the air.  Although none of us like to be covered with sweat, sweating does help keep us from overheating.  Since birds do not have any sweat glands, one of the ways in which they eliminate excess body heat is through a behavior called gular fluttering (more commonly known as panting).

        When a bird is panting, it opens its mouth and flutters its neck muscles.  This increases the airflow across the airsacs in its lungs.  This, in turn, helps excess heat and moisture to pass from a bird’s lungs into the air expelled when the bird breathes out. 

        Now you know why birds don’t sweat the heat.

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: HUMMINGBIRDS PREFER NECTAR WITH PLENTY OF SUGAR

   

    RUBY-THROATED HUMMINGBIRD FEEDING

       Ruby-throated hummingbirds do not feed at flowers containing small amounts of nectar.  In fact, they refuse to feed at flowers harboring less than 12 percent sugar.

       Studies have found that they prefer to dine on nectar that contains anywhere from twenty to twenty-five percent sugar.

       With that in mind, is it any wonder the recommended ratio of sugar to water in the sugar water we most often feed hummingbirds dining at our backyard feeders is one part sugar to four parts water?

HAVE YOU BEEN LOOKING FOR A QUESTION MARK

        The question mark is one of the most uniquely shaped butterflies you are likely to see in your backyard. 

       The wingspan of this butterfly ranges from 2 3/8-2 5/8 inches wide. Each of the butterfly’s fore and hind wings displays a deep downward pointing hook.  The ragged outer margins of the wings dip inward toward the body.  The dorsal surface of the wings is rusty orange and marked with black markings.  Meanwhile, the ventral surfaces of the wings are light gray to tan.  In summer, the outer edges of the wings are shaded with violet hues.  The butterfly is named for the distinctive silvery question mark found on the ventral surface of the hind wing.

       Do not waste your time looking for this butterfly visiting your flowers.  Although question marks will occasionally nectar at flowers, they much prefer to dine on an odd variety of items including sap, animal dung and rotting fruit.  Interestingly, question marks sometimes become intoxicated on the alcohol produces by decaying fruit.  When they are in this condition they move above erratically and will even let you touch them.

       The best way to attract this butterfly to your yard is to leave rotting fruit beneath your fruit trees and to provide them with caterpillar host plants.  Two of their favorite hosts are elm and hackberry.

       Early morning, before it gets really hot is an excellent time to go looking for question marks.  At that time of the day, question marks can often be located basking in the morning sunshine.

       In the afternoon, males spend much of their time displaying for females.  When they are engaged in these displays, they will sometimes closely approach anyone walking near them.

BACKYARD SECRET: AMERICAN GOLDFINCHES NEST DURING THE HEAT OF SUMMER

       In Georgia, the American goldfinch is one of the last birds to nest.  In fact, most of these colorful birds don’t even begin nesting until late June.  However, most nesting occurs during July and August.  Remarkably, some American goldfinch nests remain active into September.

       In spite of the fact they prefer to nest in habitats featuring small trees and shrubs, they will also nest in our backyards.  If you are fortunate enough to have a pair of American goldfinches nest in your yard, you are in for a real treat!

       It seems the female is charged with the with the duty of incubating the eggs.  During these 12-14 days, she will spend upwards to 95 percent of her time perched atop her fragile eggs.

As you might imagine, this leaves little time for to feed.  In spite of this, the dedicated female never goes without food.

AMERICAN GOLDFINCH (Male)

       The reason for this is every hour or so throughout the day her mate will circle the nest.  If the female is hungry, she will softly call to him.  Upon hearing the call, he quickly drops down from the sky and lands near the hidden nest.  Once he lands the female will leave the nest and land nearby.  He then quickly feeds her a nutritious meal of partially digested seeds.  After eating, the male flies away and the female returns to her nest.

       If you suspect American goldfinches are nesting in your yard, be on the lookout for a male repeatedly flying in circles over a small tree or shrub.  If your suspicions prove to be correct, you will have the wonderful opportunity of witnessing this rarely seen behavior on regular basis.

BACKYARD SECRET: CARDINALS HAVE TWO VOICE BOXES

      The song of the northern cardinal is one of the most beautiful songs we hear in our backyards.  Remarkably, like other songbirds, the cardinal produces its melodious notes using not one but two voice boxes. 

       If you listen carefully to a cardinal song, you will notice each phrase of the bird’s song is composed of a blending of both high and low notes.  The lower notes are created in its left voice box.  Meanwhile, higher notes are formed in the bird’s right voice box.  Working harmoniously, the two voice boxes enable the cardinal to create a distinctive and pleasing song enjoyed by homeowners across the state.

ATTRACTING THE SUMMER TANAGER TO YOUR YARD IN SUMMER

       Now that summer has officially arrived, days are getting shorter with each passing day.  When this occurs many migratory birds beginning putting on the fat that will fuel the migration to their wintering grounds.  One such bird is the summer tanager.

       The summer tanager is a common resident of wooded backyards across the state.  However, in spite of the fact, males are cloaked in red feathers and the females display a two-toned plumage (olive-green above, yellow below) and sport large pale bills, this colorful bird often goes unnoticed.  This is because it often feeds in the tops of trees.

       The summer tanager primarily consumes lots of insects such as bees, wasps, cicadas, yellow jackets and grasshoppers throughout the spring and early summer.  However, throughout much of the summer as it is packing on fat in preparation for their autumn migration, fifty percent or more of its diet consists of fruits and berries. 

       Consequently, if you would like to attract local and migrating summer tanagers to your backyard at this time of the year, the best way to do that is to provide them with the fruits and berries they relish.  If you look around your yard and cannot find any of the plants that produce this much-needed food, you should make every effort to add some of them to your landscape.

       Here are some of the plants that provide fruits and berries gobbled up by summer tanagers as they prepare before they embark on their long flight to Central and South America:  blueberry, blackberry, grape, hawthorn, flowering dogwood, rough-leaf dogwood, pokeberry, and black gum.

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.