Winter Gets Serious But Life Persists

February 8, 2016

Nature Notes by Bill Dunson

After a prolonged warm fall and winter, the cold fronts began to arrive in SW Florida and the animals had to cope with much cooler weather and periodic strong winds and heavy rains. Despite these somewhat harsh conditions, a diverse and beautiful display of life continued in between the bouts of cold weather. An additional factor was the occurrence of red tide that killed some fish and cleared the beaches of tourists. A photo I took Jan. 31 on Don Pedro Island beach shows a deserted stretch of beach during a bout of aerosol red tide whipped up by strong NW winds. If you can tolerate the almost unbreathable air during an episode of red tide, it is refreshing to be able to walk the beaches with few or no human companions.

Once cold fronts have passed, the winds decline, the sun is out, and there can be times of intense insect activity. For example I photographed a zebra butterfly, a species requiring passionvine for its caterpillars, drinking nectar from Spanish needles and tassel flower in our yard. These “weeds” are both beneficial exotics that offer wonderful winter flowers for native butterflies without being cultivated. You just have to tolerate them in your yard and not pull them up or mow them! I also came across a large bird winged grasshopper on a mulberry plant seemingly basking in the sun. They have catholic tastes and represent a genus (Schistocerca) that can occur in plague proportions.

The very common brown or Cuban anole is an iguanid lizard that is an exotic but has become a major food staple for other reptiles and birds. It continues to hold territories during the winter and woo females, as shown here by a male that is extending its colorful dewlap in a sunny spot along a tree trunk. It could easily become food for predatory birds such as the loggerhead shrike which is known to pierce its prey and hang them on barbed wire fences.

During a strong wind storm I found a number of meadowlarks in breeding condition singing and showing off their extraordinary yellow breasts. These birds require grasslands such as are found in cow pastures and thus can thrive on ranches.

Aquatic birds seek out protected locations during storms and continue their specialized feeding. The oystercatcher has a spectacularly colored chisel like bill, the better to pry open bivalve molluscs. Since the male and female look the same, the purpose of the bright bill color is a mystery. The pair of lesser scaup shown here is a duck that feeds on invertebrates such as molluscs and seeds by diving down and gathering them on the bottom in shallow water. Some winter along our coasts and rivers in tidal waters, but breed along inland waters in the NW US, Canada and Alaska.

We are fortunate in Florida to continue to have active populations of animals during the winter. Thus we snowbirds can enjoy the interesting behaviors of species that either have migrated, hibernated or become mostly inactive in northern climes.

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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