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“Are those bugs all over the ground?” This is a question I often get when our Island outings pass by a Saltmarsh. What people are referring to are the great numbers of small fiddler crabs that live in this biologically rich environment. There are at least three species of fiddlers that inhabit Cumberland’s Saltwater Wetlands. As the name implies, this crab has a kinship with the fiddle as the large single claw of the male crabs in a way resembles that instrument. During the warmer months when fiddlers are active, male crabs can be seen waving this pronounced claw in the air in an effort to attract females for breeding and to keep other males out of their territory. Fiddlers feed mainly on detritus, a mixture of decomposed organic material, mostly grasses produced in the marshes. These prolific crabs have specialized mouth parts that can seperate the organic food they ingest from the mineral sand, which is spit out in the form of small round pellets. This feeding behavior qualifies the fiddler as a slow land builder. Over the years I have come to realize these little crabs play a big roll in the ebb and flow of the Saltmarsh Eco-system. For example: many animals eat fiddlers. Along with several species of wading birds, mammals such as mink and raccoons feed heavily on this abundant food source at low tide, when the muddy ground in the marsh becomes exposed. During periods of high tide, several species of fish as well as the much larger blue crabs eat fiddlers. So fiddlers fill a niche here between detritus and numerous predators.
Fiddler crabs most likely to be seen along the edge of a Saltmarsh are the colorful Sand fiddlers also known as Chinabacks: so named because of the intricate designs on their shells that look like painted porcelain china. As these roughly one inch long crabs gather along the Saltmarsh shoreline they are easy to see and sometimes mistaken for “bugs” by visitors to the Island. However these tiny crabs spend much of their lives burrowed in the mud. During the colder months when fiddlers are less active they are safer underground. But as temperatures rise this time of year we see the fiddler on the Marsh.
April is the month when the Islands most colorful bird makes its first appearance after a migration from the West Indies and Central America. Painted Buntings arrive to begin nesting on Cumberland. As in most bird species, male buntings are the ones with the most distinctive plumage. Biologists believe this is to direct predators away from the females as well as to attract the females to the most colorful males. Whatever the reason, male Painted Buntings are well named with their bright red, blue, yellow and green plumage; while the females are completely green. These birds are only about five and a half inches long but so brightly colored they always grab the attention of those who see them. Unfortunately bunting populations have been decreasing at a rate of about three percent each year. This is mainly due to the fact they are losing nesting habitat in large areas of their Spring and Summer range on the coast of Florida; areas that have been heavily developed. On Cumberland however there is still suitable habitat for these beautiful birds, especially in the thicker edge vegetation between forest and wetlands. This is the type of habitat found around the Greyfield Inn and also nearby Dungeness area; it’s the reason why many species of song birds including buntings are often seen here.
Although Cumberland lies within the Southern temperate climate zone there is a strong sub-tropical influence here and the return of the bunting in spring serve as a reminder of this fact.
Spring is officially here and so are warmer temperatures needed to bring out the reptiles. Cumberland is home to over forty species of reptiles, the largest and most noteable being the alligator. This is the breeding season for these top predators so the bellowing roars they make to locate mates will be heard in the freshwater wetlands on the Island. Alligators are freshwater animals that will venture into saltwater to feed. During the warmer months they are seen in the saltmarsh and tidal creeks on the west side of the Island. Some alligators on the north end of Cumberland have been known to enter the ocean at night to feed on large schools of mullet that gather there during the summer months. But alligators cannot live in a salty environment full time because salt will eventually dehydrate them so they have to make it back to freshwater in order to survive.
As one might expect, we get a lot of questions about these high profile animals such as “How big do they get?” The largest alligator on record is a 19′2″ animal found in Lousiana.
On Cumberland a twelve foot alligator would be considered a very large specimen. Under ideal conditions of food and climate, young alligators grow about one foot a year until they reach six feet, then the lengthening process slows down as the animal grows thicker. The males grow faster than females; in twenty years a male can reach a length of about eleven and a half feet, while a female would only grow to a little over eight feet during that period. However, both become sexually mature when they are about six feet long.
An alligator nest consists of a large pile of dead vegetation close to water. In this mound the female can lay anywhere from 20 to over 50 eggs. The incubation period is about 65 days and the temperature of the eggs in the nest will determine the sex of the young. Eggs below 86 degrees will hatch all females while eggs above 93 degrees will be all males. Temperatures between these two extremes will produce both males and females but mostly females. This information came from studies of alligators mostly in Florida.
Female alligators are good mothers and are very protective of their nest and young. The young may stay close to her for up to three years before leaving to find their own new territories. On Cumberland, once an alligator reaches a length of three feet they have nothing to fear except a larger alligator. The big ones will eat the smaller ones, especially during times of drought when their normal food supply has been interrupted.
Truly wild alligators shy away from humans but can become aggresive and dangerous if people are feeding them. Recent alligator attacks in Florida involved these types of habitual animals. On Cumberland there has been one recorded alligator attack. In 1989 a man bathing in a freshwater pond was bitten by a six foot alligator that quickly released him after making contact. However, Island alligators are known to feed on large mammals such as deer, feral hogs and possibly feral horses so a human in the water cound be mistaken for something else.
The alligator is certainly at the top of the food chain in this region and the undisputed king of the freshwater wetlands. As such, they have an important niche to fill in order to keep this natural system in balance. Alligators only feed on other animals many of which are mammals that can over populate. Without predation, diseases will impact and weaken prey species. So the alligator helps to level the boom and buse cycles of these animals creating a more disease free healthier environment.
Alligators are also important in other ways. I have found that many people are fascinated by these animals; whether they be seasoned gator hunters from Florida or tourists from Europe or a northern city in this country. The fact there are large predators in the wild like the alligator that can overpower and kill a human, has a humbling effect on people. As a result, many of our guests want to see and learn more about these great reptiles. Now with the warmer Spring temperatures, alligators are becoming active again on Cumberland Island.
It’s Spring green-up time on the Island as new leaves and blooming plants are evident everywhere. Cumberland is located in the Southern temperate zone but because of the warming effects of the ocean, many sub-tropical plants thrive here including the Island’s most notable tree, the Live Oak. Although in the same genus as other oaks, Live Oaks are considered to be evergreens. Unlike most other hardwood trees, they do not drop their leaves in Autumn and lay barren over the Winter months. Instead, Live Oaks lose most of their leaves in the Spring at the same time the new leaves and pollen heads are forming.
Live Oaks are the dominant trees on the Island because they can withstand more wind and salt spray than other competing trees. The horizontal limb growth forms a broad sprawling canopy while the shallow root system spreads out to cover the same distance underground. This combination works well to stabilize the tree.
These sturdy trees with hardwood and twisted grains were the first important commodity to be harvested on the Island. In the early 1800’s Live Oak limbs with their natural curves were used for the main structural parts of the old sailing ships.
Live Oaks have an average life span of about 300 years although there are specimens in some areas that are much older. On Cumberland most of the original trees the early settlers found are now gone. But a few still remain. One tree on the Greyfield Inn property has a circumference of twenty-nine feet, and according to researchers from the University of Georgia, is about 350 years old.
Compared to other oaks, Live Oaks are fast growers, so a mature forest of these majestic trees once again covers the Island and Spring is the time when they really stand out with their new bright green leaves.
