Archive | July 2019

BACKYARD SECRET: THE PLANT WITH THE GREATEST VOLUME OF NECTAR MAY BE GROWING IN YOUR YARD

       Can you name the plant that displays flowers that contain the greatest volume of nectar?  It is not Mexican cigar, red hot poker, Turk’s cap  or one of the scores of other alien plants we plant in our gardens to attract hummingbirds and butterflies.  You might be surprised to learn it is a native woody vine known as trumpet creeper (Campsis radicans)

       The woody vine’s orange blossoms are so popular with hummingbirds it is often sold in the nursery trade as hummingbird vine.

       This plant commonly grows in yards across the state.  However, in many cases it is considered a weed and not recognized as a valuable hummingbird food plant.  The reason for this is it will climb on houses and other manmade structures.  However, if you plant it alongside an arbor, trellis, or fence away from a building, it can be an asset instead of a liability.  Trumpet creep can also be trained to take on the form of a small tree.

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.

BACKYARD SECRET: BIRDS ARE FANS OF POKEBERRIES

        Pokeweed is one of the many plants homeowners often refer to as weeds.  These objects of our distain try to grow in alongside our precious cultivated plants, invade our lawns, and are generally viewed of as nuisances.  However, some of these plants may be more valuable than you think.  One such plant is pokeweed. 

       Other than the few folks that dine on the plants tender shoots in the spring, pokeweed is not a plant most people allow to grow in their backyards.  This is unfortunate because, if allow to grow in the right spot it produces a bounty of dark purple berries that are relished by more than 50 species of birds.  Among the backyard favorites the devour pokeberries are cardinals, mourning doves, mockingbirds, and bluebirds.  The berries also provide nourishment for fall migrants such as thrushes and vireos that pass through our backyards on their fall migration.

       Although pokeberries are often considered a fall food, they are just beginning to ripen in my backyard.  This event caught the attention of a mockingbird.  Although the vast majority of the pokeberries in my backyard are still green, as soon as one turns dark purple the mockingbird gobbles it up.

       I must admit I remove pokeberries from some of my flower gardens.  Meanwhile, I let me grow in idle spots and in the shrubby borders that define the north and south sides of my yard.

       If a pokeberry takes root in a similar spot in your yard, I urge you to let it grow.  It will provide your avian neighbors with an important source of food later in the year.

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.

INDEPENDENCE DAY HUMMINGBIRD EXPLOSION

        No Independence Day celebration would be complete without fireworks.  The explosions of brilliant colors against the dark summer night add a special excitement to this festive time of the year.  However, during this special time of the year aerial kaleidoscopes of color do not have to be confined to the night.  From dawn to dusk, hummingbirds decked out in iridescent green and red streak across Georgia backyards creating their own colorful aerial displays.

       July is a special time of the year for hummingbird enthusiasts.  Beginning around Independence Day there is an explosion of hummingbirds at our feeders.  Up until then, ruby-throated hummingbirds have been scattered across the countryside living in discreet breeding territories measuring an acre or more in size.  Consequently, aside for a brief period that extends from late May into early June, large concentrations of hummers around our feeders are rare occurrences.  All of this changes after the females complete their nesting chores.  With the breeding season largely coming to an end, rubythroats begin preparing for their fall migration.

       For these flying dynamos, getting ready for this epic journey means storing the fat needed to fuel their southward flight away from backyards across North America.  These tiny birds may visit 1,500 flowers in a single day trying to put on weight as quickly as possible.

       The main sources of food are nectar gleaned from flowers, small soft-bodied invertebrates as well as the sugar water we offer them at feeders hanging in our backyards.  Since drought conditions across much of the state have resulted in a paucity of nectar-laden wildflowers this year, nectar will be in short supply this summer.  This forces the birds to look to the flowering plants and hummingbird bird feeders located in our backyards for a readily available source of energy.

       The folks that will host the most hummingbirds at this time of the year are those that had the foresight to incorporate a variety of nectar-bearing flowers into their landscape design to go along with feeders filled with fresh nectar.  If you failed to plant flowers for hummingbirds this past spring, make a mental note to do so next year. 

       Meanwhile offer your hummingbird visitors plenty of nectar.  Begin by hanging up one or two feeders.  Add additional feeders as the number of diners at your backyard cafe increase.  Make sure there is always plenty of food for the birds.  If you plan on going on vacation, ask a neighbor to monitor and refill feeders as needed.  This will help ensure an explosion of ruby-throated hummingbirds will be patrolling your feeders long after the fireworks of this Independence Day have faded away.