Coastal Marvels of Nature in SW Florida

November 24, 2017

Nature Notes by Bill Dunson

If you walk outside with a keen eye for observation you will never lack for something interesting to see. As I hiked to Stump Pass along the beach I was struck by the beauty of this stump of a dead Australian pine or casuarina. Most of these have been killed by park personnel since they are an exotic invasive species, and the ones along the beach have also been undermined by erosion and toppled by strong winds. Despite their evil qualities they have been serving as valuable nest sites for ospreys, eagles and great horned owls. As the last remaining snags decay, one wonders where these birds will find new homes. Nearby railroad vines do not lack for habitat since this beach was re-nourished last winter and their long tendrils snake across the sand. Their relationship to morning glories is quite clear from the structure of their beautiful flowers- a handy way to identify most plant families. These beach specialists produce floating seeds that will be transported by water to distant locations, some few of which may be suitable for germination and growth.

A nearby beach washed carcass of a boxfish/cowfish at Stump Pass State Park was amazing to examine closely. The scales have been fused into astonishing hexagonal plates that cover almost the entire body. Clearly this must reduce the mobility of the fish, but increase its ability to survive an attack by a predator. Most species of boxfish and the related puffers have chemical defenses also. On Palm/Knight Island I found another beach washed carcass of a most interesting batfish. This bottom dweller can “walk” on its fins and is a type of anglerfish that has a remarkable lure to attract prey on its first dorsal spine. It has some minimal skin armor but likely escapes predators primarily by camouflage.

Caterpillars are the larval stages of moths and butterflies and are food for many other animals. They develop mechanisms to resist predation in part by becoming venomous and/or toxic. While leading a nature walk in Tippecanoe 1 preserve, we encountered a puss caterpillar (larval stage of the southern flannel moth). This is a venomous species which releases poison from hollow spines and is one of the most toxic caterpillars in N America. Yet it does not advertise this striking defense and moves very slowly. In contrast the echo moth caterpillar is brightly colored and is often observed going “walkabout” for unknown reasons. Indeed it can move very fast and although capable of eating many types of plants, is one of the very few caterpillars that can eat the toxic coontie. Apparently it is not venomous but is likely to be toxic if eaten. I found this large echo caterpillar on a sidewalk next to a planting of ornamental coontie. As is the case for its tiger moth relative the “wooly bear,” it may cause some minor dermatitis if handled.

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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