A Renewed Appreciation of the Passage of Time

Humans tend to live as if time was of no concern and assume that conditions around them will stay rather constant. Living on a barrier island (or a volcano or a seismic fault) will teach you otherwise since the environment can and will change somewhat unpredictably and interfere with human activities. Those of us that live on Manasota Key on the Gulf of America western coast of Florida have been taught a severe lesson in humility by a series of hurricanes that delivered strong winds and a 10 foot storm surge. None of these are unexpected but of course you can always hope that you will be lucky and escape the worst conditions. Another factor of major importance is the increases (since the last ice age) in sea level. The graph shows this and indicates also a recent acceleration in the rise in sea level. Now the Bible warned about building your house on such an unstable platform as sand which is what barrier islands are made of. Increased sea level makes this an even more dire warning yet people continue to build and live on barrier islands for the obvious access to the beach. It is clear that humans will have to move inland at some stage, which has already arrived in some localities. In this context I find it interesting to contemplate how long my barrier island has been in existence. Manasota Key has likely been present for several thousand years in its present configuration. During the height of the recent ice age the coast would have been at least 100 miles to the west. Prior to European colonization Indians lived here and there is evidence for that in my own yard. I occasionally dig up whelk shells that have been modified by humans not only to extract the meat but to make them into useful implements for digging and fighting. Several graveyards have also been found nearby but we know very little about these early inhabitants who left no written records. Some other shells found as constituents of gravel placed on roads and paths can be much older- this Wagner’s arc shell is a guide fossil for the Pliocene middle Calossahatchee formation which is believed to be 3+ million years old.

After the storm surge from hurricane Milton in October 2024, many plants in our yard died from exposure to sea water, especially those in a low swale out front. A strangler fig which had been huge for the entire 30 years of our presence died and was cut down recently. My son happened to be visiting and was interested the the age of this tree since he had visited the sites of bristlecone pines in Utah which are famous for being thousands of years old. He cut off several pieces of the stump several feet above the ground.and counted the rings. There is no way to know whether these rings are annual growth rings or represent some other chronology based on season or weather. In any case he tabulated almost 600 rings. I have consulted a number of dendrochronologists who specialize in analyzing tree rings and have not yet found anyone who is familiar with the strangler fig which is a tropical species growing near the northern extent of its range. One suggestion is that even if these 600 rings are not annual, they may represent perhaps two to three rings per year on average which would make the tree about 200-300 years old. One interesting speculation from this finding is that during its growth period this tree has not been subjected to a lethal exposure to a sea water storm surge such as happened in October, 2024. This provides a type of independent confirmation of the fact that this island location has not been submerged by sea water during the past 200-300 years. Clearly the odds for this type of event have now greatly increased!

Strangler figs (Ficus aurea) are a very interesting species. They produce enormous numbers of small fruits pollinated by specialized wasps that are eaten by birds and mammals. The seeds are deposited in feces on other trees, especially, cabbage palms. They germinate and produce a seedling that very slowly sends roots down to the ground. Subsequently the fig wraps roots and its trunk around the host tree and kills it. This seems to take a very long time in my experience, likely many decades. The soil is almost pure silica sand and has very few nutrients except those derived from decomposition of plants.

The impact of hurricane Milton on Blind Pass just to our north has been very interesting. Huge amounts of sand were thrown up by the waves and covered most of the island vegetation extending into the bayside mangroves. One of the few trees to survive this invasion of sand has been the sea grape. It has a very large waxy leaf which also happens to be very beautiful. It is strangely enough a member of the buckwheat family- a very unexpected geneology for this salt tolerant tree. Given the death of so many plants in my yard (Spanish stoppers, mango, wild coffee, myrsine, Walter’s viburnum, Mexican sunflower, Yaupon holly, cocoplum, Hong Kong orchid, etc) I have replanted many sea grapes and other haolphytes such as necklace pod, butonwood, yellow elder, and sea hibiscus) thinking of future storm surges to come.

It is rather surprising that so many animals survived the devastation of hurricane Mlton> I surmise that any that could climb would have gone into the trees to escape, some would have remained in burrows with an air bubble, and some might have simply swum until the surge disappeared possibly within hours. I have replanted some “FL friendly” non-native perennials to provide flower nectar that natives do not. produce in winter. Some butterflies I have seen recently include the astonishing mangrove skipper, many monarchs (attracted to non-native tropical and giant milkweeds), Gulf fritillaries, Dorantes skipper and Cassius blue.

Many vertebrates have survived the storm both native (rabbits, box turtles, gopher tortoise and even a female bobcat with a half grown kitten) and non-native (iguanas-ctenosaurs). Our local ospreys are constant companions and wage warfare against the bald eagles to retain their nest site in a tall Norfolk Island pine.

We might consider ourselves lucky to have weathered several hurricanes and to have witnessed how nature remains strong in the face of such environmental disasters. Change is a constant certainly and we can no longer think that our island life is forever- clearly the natural process of island migration towards the mainland is underway and is likely accelerated by global warming. We must change with such events and try to be as resilient as the animals and plants that live on barrier islands.