A Christmas Nature Ramble

December 19, 2014

Nature Notes by Bill Dunson

No matter where you find yourself at Christmas you can enjoy the natural world in all its splendor. In Florida we can be raking leaves instead of shoveling snow and working at attracting birds and butterflies to our yards. One of the most useful devices for attracting birds is the drip water bath which is effective due to the sound and sight of water ripples. So many people have asked me about this that I have attached a photo of one of my two baths. A dripper ( http://shop.wbu.com/p/wbu-drip-or-mist?pp=12 ) is attached to the nearest outside faucet via an irrigation water tube and placed on a suitably shallow pan (I have used a glazed pan obtained from a garden shop placed on top of a water bath pedestal since most bird baths are too deep or steep sided). A bucket of water next to the bath discourages mammals from tipping the bath over. Birds drink from the drip and bathe in the bath and provide quite a parade at certain times of the day. Some vegetative cover nearby is advantageous for many species. One of our most exciting visitors to the drip this week has been a FOS (first of the season) female painted bunting. We hope her male companions are not far behind. This species provides one of the most spectacular examples of a very gaudy male and an inconspicuous female; but the male does not lose his bright colors during the winter as does the male indigo bunting

A recent interesting insect visitor to our yard has been a spotted oleander caterpillar moth. This fairly recent immigrant to the US (about 1978) feeds on poisonous oleander as a caterpillar and the adult moth retains toxic chemicals and thus can fly freely during the day, protected from predators. However it also appears to be a wasp mimic and thus has double protection.

The appearance of periodic cold fronts is common in Florida during the winter and these provide some of the most beautiful clear and sunny but cool days. This stimulates reptiles into basking behavior which is highly developed in turtles. The very large peninsula cooter turtles are herbivorous and seem to need a lot of sunning to aid digestion. At Wildflower Preserve we have provided some rafts for this purpose. The adult females are huge with conical shells designed to defeat the crushing jaws of alligators. They often extend their legs and open their webbed feet to catch all the rays and perhaps to clean their skin of parasites or algal growth. These rafts have become so popular that there are traffic jams with turtles bumper to bumper with no room to spare.
Other species such as birds also use the rafts for resting, such as this green heron which seems to possess all colors other than green!

Our local ospreys are willing to use all sorts of supports for nest building if they are near their favorite fishing spots. This pair built on top of an electric pole which had pointed spikes placed to discourage such nesting. While the ouch factor might seem a problem, the birds have worked around this issue and indeed the nest is probably much more resistant to wind damage than normal nests. Ospreys are unusual in that they are fish specialists which apparently never eat anything else. I came across this female feeding on what seems to be a sheepshead and starting to eat it at the head.

One of our most spectacular birds is the roseate spoonbill, which feeds on a wide variety of small aquatic prey that are trapped in its flattened bill. It never sees its prey and likely avoids competition with similarly sized wading birds by eating such small prey. The adults become more pink with age but why are they so pink? One answer is that they are what they eat! The small crustaceans they feed on supply carotene pigments which are deposited into the feathers. Since males and females look the same, the evolutionary purpose of the coloration may just be species identification and possibly recognition of individual vigor for mating selection. Despite the biological reasons we may simply enjoy their breathtaking beauty.

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.

View all posts by Bill Dunson