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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?

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.

THE RUBY-THROATED HUMMINGBIRD’S DISPLAY FLIGHT

         One of the most fascinating animal behaviors can you see in your backyard is the display flight of the male ruby-throated hummingbird.

         Over the years, I have been fortunate to witness this fete on a number of occasions.  However, until last week I had never observed it three separate times in a matter of a couple of days.

        This acrobatic maneuver is unmistakable.  The male will repeatedly fly to and fro in a wide U-shaped arc.  Often the male is so adept at retracing the path of his previous arc it appears he is coursing along an unseen track.

        At times, the bottom of the arc brings the male so close to the head of a perched female you are convinced he is going to collide with her.  As he approaches the seemingly unperturbed object of his affection, the buzzing sound created by the air passing through his tail and wing feathers becomes appreciably louder.  This dramatic display is designed to convince the female he is a suitable suitor.  However, the only time she gives him the time of day is during a handful of days prior to her laying a clutch of two eggs.

        After I enjoyed the sight of a male rubythroat engaged in an aerial display, I related the story to my wife.  She said she had never been lucky enough to see the display.  Remarkably  the very next day, while we were both standing on our deck a male suddenly appeared and performed the aerial fete in front of us.  In fact, one side of the U-shaped arc was so close to our heads I thought he was going to collide with us.

         A couple of days later my daughter was standing on the deck with us when she suddenly exclaimed,  “What is that hummingbird doing?”  I looked up and could not believe my eyes–a male rubythroat was once again engaged in a display flight.

        Observing three ruby-throated hummingbird aerial displays and being able to be with my wife and daughter when they both witnessed their first courtship displays is something I will never forget;  this is backyard wildlife watching at its best.

A HUMMINGBIRD AND CHICKADEES BROUGHT BACKYARD SURPRISES

        I learned a long time ago to expect the unexpected whenever I venture into my backyard.   Recently two events that took place in my backyard in the same afternoon once again demonstrated you never know when you are going to witness something special.

        In this case, I walked outside to take a close look at an extremely large cluster of long, tubular-shaped orange, red, and yellow blossoms poised atop one of our red-hot poker plant’s long flower stems.  While standing within six feet of the large torch-like floral cluster, a ruby-throated hummingbird suddenly flew in and began feeding on the backside of the cluster of flowers.  I could tell the bird was there because the tips of its wings projected beyond the sides of the flowery torch.  I stood transfixed, savoring the opportunity to be standing so close to the feeding bird.  All the while the bird fed I was hoping its feeding activities would bring it around to my side of the torch.  I would like to report my vigil was rewarded; however, the bird eventually flew off without circling the blossoms.  As it flew away, I could see the bird was an adult male rubythroat.

        About an hour later, I went outside to see what else was going on outside my backdoor.  This time when I reached the top of the steps leading from the deck into the yard, an adult Carolina chickadee perched in a nearby dogwood caught my eye.  Since the bird seemed agitated I began looking about to see if the family cat was nearby.

        Although I did not spot the cat, I saw four young chickadees flying from plant to plant.  The birds had obviously just fledged from a nearby log nesting structure.  Not wanting to stress the young birds, I watched the birds from the deck.  It was obvious the youngsters were testing out their wings for the first time.  They flew very slowly, never attaining an altitude of more than six feet.  These flights were short and ended in clumsy landings.

        Fearing my presence would alert the cat to what was going on, coupled with my desire not to hinder their initial attempts to fly, I went back inside.  An hour or so later I went returned outside and was pleased the new squadron of chickadees had moved on.

        I could not believe how fortunate I was to enjoy two fantastic wildlife adventures in the same afternoon.  While I always find something of interest whenever I make a backyard trek, it is not often that I experience two very special encounters with my backyard neighbors within hours of each other.

        What a day!

DO BACKYARD BIRDS PRACTICE MONOGAMY?

        Up until a few decades ago, biologists believed that as many as 93 percent of songbird families practiced monogamy.  However, since the development of DNA fingerprinting in the 1980s, we now know some birds that appear to be devoted mates will stray.

        This earth-shattering realization came about quickly.  For example, by 2002, researchers discovered that up until that time a meager 14 percent of the songbirds tested were truly monogamous.  Research has shown 19 percent of the nests of supposed monogamous birds are home to at least one nestling that was sired by a father different from the rest of its nest mates.

        A few of the backyard birds that are promiscuous are the eastern bluebird, ruby-throated hummingbird, house finch, and red-winged blackbird.

        It would appear that some of our backyard feathered neighbors live soap opera lives.

PROVIDING NESTING MATERIAL FOR HUMMERS

       Have you ever given any thought of trying to provide nesting hummingbirds with a source of nesting material?  I must admit while I have placed pieces of cotton in a wire suet feeder in the spring hoping it might be used by nesting birds, I never considered the possibility the white fibers might be used by a ruby-throated hummingbird.  However, three events have caused me to change my mind.

        Several years ago, I presented a hummingbird program to a garden club in southwest Georgia that met in the home of one of its members.  While I was setting up my projector and screen, the host asked me if I ever heard of a hummingbird using cotton to build a nest.  I told her although I had not, I could see how hummingbirds might incorporate cotton in a nest. 

        She then went on the explain that she had seen a female hummer collect cotton in her backyard.  It seems she planted a cotton seed in a pot that sat near her house.  The seed germinated and grew into a healthy plant festooned with balls of cotton.  Since the plant looked attractive, she left it in pot throughout the winter.

        The following spring while she was standing in her living room, looking out across her patio a female hummingbird flew down, plucked some cotton fibers from a cotton ball, and flew up to a nearby tree.  The bird repeated this behavior several times.  Although she never actually saw the bird using the cotton to build a nest, she surmised that is what the little bird was doing.

        I was reminded of this homeowner’s experience last week when I received an email from a man relating that he had witnessed a female hummingbird collect a bit of cotton from a suet feeder filled with cotton batting.  This prompted him to search for a nest.  Remarkably, his efforts paid off and he discovered a hummingbird nest close by.

        Earlier this week I mentioned this event to a cousin.  He was so intrigued by the story he went out and bought a wire suet feeder, filled it with cotton, and hung it out near his home.  Unbelievably before the sun set he spotted a female hummer pulling strands of cotton from the  feeder.  Now he is looking for a nest.

        With this kind of success, perhaps this is something we should all try.  Even though a hummingbird might not avail itself of the cotton we offer, chances are other nesting birds will.  

EXPECT TO FIND CAROLINA WREN NESTS IN ODD PLACES

        Although the Carolina wren is considered to be a cavity nesting bird I must confess I have never found a Carolina wren nest in a natural cavity or nesting box.  In fact, when it comes to Carolina wren nests, I have learned to expect the unexpected.

        I have found Carolina wrens nesting in my well house, beneath the cover of a propane tank as well as in a cardboard box sitting on a shelf in my garage.  Others have discovered Carolina wren nests is strange places too.

        For example, their nests have been located among the rocks of  stonewalls, clothespin bags, hanging baskets, open paper bags, mailboxes, buckets, as well as in old hats and shoes.

        One year Carolina wrens nesting in North Carolina chose as their nesting site a Jeep Wrangler.  They constructed their nest where a shock absorber was attached to the frame of the vehicle.  What makes this nesting so fascinating is the fact the vehicle made three trips before the nest was discovered.

        Carolina wrens apparently have no problem nesting in vehicles that are driven about.  Decades before the famous Georgia ornithologist, Thomas Burleigh reported that, in 1928, a pair of Carolina wrens nesting in Athens chose as their nesting site a touring car.  The vehicle was left near a sawmill for two days.  During this time, the wrens began building their nest beneath the hood of the car.  When the car was driven away and returned the next morning, the unperturbed birds resumed construction of their nest.

        If you have never located a Carolina wren nest on your property, perhaps you have been looking in the wrong places.  This year focus your search on places you would never expect a self-respecting wren to nest and you just might find the nest that has been eluding you for so long.  

        Good luck!

LEAD CAN AFFECT MOCKINGBIRD AGGRESSION

          We Georgia homeowners are well aware of the fact the northern mockingbird is one of our most aggressive backyard birds.  In fact, if you are like me, it is hard to believe you would want them to be any more aggressive.  However, the results of a study published by Stephanie McClelland in the journal Science of the Total Environment suggest that the amount of lead found in the soil within a mockingbird’s territory can affect its aggressiveness.

    The study was conducted in neighborhoods scattered across New Orleans, Louisiana.  The data collected during the study found mockingbirds living in areas where high levels of lead are present in the soil are more aggressive than those inhabiting neighborhoods where soils are not contaminated with this pollutant.

         Now that I know lead can affect the level of aggressiveness displayed by mockingbirds, I cannot help but wonder if this element is affecting the mockingbirds living in my yard.  I hope that is not the case.