Birds Do It, Bees Do It . . .





Now that summer is well underway, you might think that the breeding frenzy so typical of the spring time is over. That seems far from the truth based on my observations lately. Many species are still continuing or even starting their reproductive cycles.

My favorite beetle, the brilliantly metallic-green six spotted tiger beetle, was photographed mating next to my cabin. Beetles (order Coleoptera) are the most abundant taxonomic group and can thus be very difficult to identify. J. B. S. Haldane, an early 20th century English scientist, is quoted as saying that ” God has an inordinate fondness for beetles.” The enormous numbers of beetles compared to other species of animals remains a paradox to this day.

Another group of insects that can be challenging to identify are the damselflies. I built several ponds without fish specifically to encourage aquatic insects that cannot coexist with these predators. As a result I noticed many amber-winged spreadwing damsels mating and laying eggs in stems of cattails around this fish-less pond. The eggs later hatch and drop into the pond to develop until they metamophose into the adults. The adults of another aquatic and usually stream living insect, the larval stonefly, has recently been found at our backdoor in the morning. The adults emerge from the water only to breed; they do not feed. This strange (to us) life cycle also occurs in the silkworm moths. I found an adult female on our porch, attracted to the lights at night, which could be either a promethea or tuliptree moth- they are sibling species that are quite difficult to tell apart. Virtually the entire life is spent as a caterpillar, followed by a few brief days looking for a mate to breed without feeding.

One of our most striking amphibians, the bullfrog, has a very loud call which is made by the male to defend its territory and to attract females for mating. I found some egg masses floating on the surface after night time breeding. This photo shows a female in our pond, which can be recognized by the eardrum being about the same size as the eye. Males have a much larger eardrum which suggests that the purpose of the jug-o-rum bellow is more to repel males than to attract females. Larger males have been shown to occupy better territories so apparently the size of the male may be conveyed by the frequency of the call.

Bluebirds continue to breed multiple times and this recent nest with four beautiful eggs is the second nesting for this pair. Bluebirds are in the thrush family (Turdidae) which often have blue/green eggs whether nesting in the open as robins or in a cavity as do bluebirds. Thus the purpose of the egg color is unclear except as a familial characteristic. In our area the major competitor with bluebirds for nesting boxes is the tree swallow, which fortunately for the bluebirds usually only nest once per season, leaving some potential nest sites available after the swallows finish.

My least favorite local mammal now has beautiful young fawns with their spotted camouflage pattern. Unfortunately they are present in far more than normal numbers and as a result have seriously damaged forest ecology by browsing wildflowers and tree seedlings. They have changed much of the future forest by removing all but a few species in the lower five feet of the forest, not to mention flowers and shrubs in yards.

While there remains much evidence of animal breeding still in mid-summer, the bulk of reproduction will soon pass. So enjoy this seasonal orgy while it lasts.

Bill Dunson

About Bill Dunson

Bill Dunson, born in rural Georgia, skipped 12th grade and went directly to Yale. Bill subsequent-ly received a PhD in Zoology from the University of Michigan, studying softshell turtles. Bill is Professor Emeritus of Pennsylvania State University thanks to a career spent entirely at that institution, teaching and doing research on the physio-logical ecology and ecotoxiciology of reptiles, amphibians and fish. Always curious about nature, Bill has dedicated his life to learning and sharing his knowledge with others. He has served on many advisory boards here in Southwest Florida to preserve the water that gives life to our region.

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