Natural Systems
The Bay's Ecology Under Stress
South Florida is home to more than just supermodels and star athletes. Not far from the spectacles of South Beach lies one of the world"s best-hidden and most sensitive ecological treasures: Biscayne Bay and the surrounding waters.
The bay, home to one of the busiest ports in the world, is also home to 512 species of fish and more than 800 species of invertebrates. Coral formations comprise the world's third largest reef. However, with more than one-third of Florida"s threatened and endangered species residing in Biscayne Bay, the state of the reef's fragile ecosystem has become a major concern.
An intimate habitat, the bay"s ecosystem harbors two primary elements " mangrove forests and coral reefs " and one primary problem " freshwater runoff. Each of these three ecological features is an integral part of what makes South Florida a popular tourist hotspot.
Tourists and locals alike take advantage of kayaking, snorkeling and fishing in the bay. Ironically, they also leave something behind: their footprints on the environment. As a result, the whole of Biscayne Bay now faces a plethora of problems ranging from the growing development of Miami to the effects of global warming.
Mangroves
"Mangrove" is a taxonomic term used to refer to a group of unrelated plants that have adapted to living in tropical seawater. D. Scott Taylor, who has a doctorate in marine biology, said there are three primary species of mangroves in Florida: red, black and white.
Extremely prominent on the shores of Biscayne Bay, the main difference amongst the three types - aside from their appearance - is where they might be found. For instance, reds are found at the lowest elevations followed by the blacks. The whites occupy the highest points.
The mangroves directly affect the bay's health as well as the success of the species living in and around it. The forests are home to hundreds of aquatic and terrestrial species and protect the land from erosion and storm damage.
"Mangroves filter runoff from the landscape, absorbing nutrients that would otherwise enter directly into the aquatic system," said Taylor, who is the Central Region Land Manager for Brevard County"s Environmentally Endangered Lands Program. "They also protect the shoreline from storm surge, which is very important."
Although all mangroves are protected under state law, which dictates that they cannot be removed or trimmed without a permit, Taylor estimates that less than half of the initial mangrove population remains in Biscayne Bay.
"Mangroves no doubt once used to line the entire shoreline of Biscayne Bay, now largely replaced with seawalls, condos and bulkheads, especially in the northern part of the bay," Taylor said.
The pollution and destruction that result from tourism and construction are extremely damaging to the bay, particularly its shorelines.
"Overpopulation is the root cause of most environmental problems in Florida," Taylor said. "Everyone wants to live on the shoreline and the mangroves, etcetera are always 'in the way.' Oil spills can also have disastrous consequences on the environment."
Since urban sprawl is not going to come to a screeching halt anytime soon, one of the only ways to preserve the mangrove ecosystem is to be more stringent with the enforcement of existing laws and make developers pay the price for illegal removal of these charming trees.
Coral Reefs
Though Biscayne Bay is most commonly recognized for its glistening blue waters, a great deal of its beauty lies beneath the water's surface with the coral reefs. These reefs are made up of living animal corals related to jelly fish and sea anemones.
Corals are polyps with stinging tentacles that are partially encased in calcium skeletons, surviving off nutrients and plankton found in the ocean waters. Billions of these polyps are required to build a coral reef as the coral formations build on top of one another.
Coral reefs require very specific conditions in order to survive, let alone thrive. The water temperature must be no lower than 68 degrees and the coral must not be deeper than 200 feet, as these animals require light. Also, the water must be relatively pollutant-free.
"Reefs are one of the more sensitive indicators of water quality," Taylor said. "[They are] sort of the oceanic canary in the coal mine."
If not, all of these oceanic conditions are met, the reefs can perish rather quickly.
As urban Miami grows, fertilizers and pollutants from cars make their way into runoff that gets flushed into the Bay. Global warming has also had an impact on the Bay"s reefs. Not only have oceanic temperatures risen but warming has strengthened storms, resulting in the breaking and battering of coral by hurricanes.
"If reefs disappear, there is a great loss of fish habitat mostly just because their hiding places are gone," Taylor said. "Coral reefs also produce a lot of food that reef fish need " crustaceans, etcetera " and they provide cover for juveniles to grow up in."
Another factor threatening the reef's ecological balance is over-fishing. When a species of fish responsible for eating the algae that cover the coral is over-fished, the algae accumulate on the reef and smother it. But, as Taylor pointed out, that's not the only consequence of over-fishing.
"Over-fishing is one of the worst problems in marine resource management and Biscayne Bay is no exception," he said. "Fishing tends to remove the larger predators first and these bigger fish are the key reproductive component of the system. So, without them, the fish reproduce at a smaller size. This leaves too many of the smaller herbivore fish which overgraze the reefs."
Marine Protected Areas (MPAs) aim to reduce over-fishing and coral decay through the establishment of "no-take zones" in which fishing, collecting or mining of any kind are prohibited. The reefs need protection for their own safety and survival to ensure future tourism and to protect an area teeming with research possibilities.
"Coral reefs are the rainforests of the sea and should be protected just because of their immense biodiversity," Taylor said. "They have huge commercial value and recreational value."
Some scientists estimate that nearly 80 percent of the coral in the Florida Keys is now dead due to disease and bleaching. News of declining reefs may make some citizens feel helpless but, even if they aren"t scientists, they still have the ability to change the situation.
"What citizens can do at the political level is lobby for laws to protect water quality and lobby for regulations to prevent carbon dioxide emissions," Taylor said. "Also, when on the water, people can avoid anchoring boats in coral and should refrain from touching the coral when diving."
Fresh Water Runoff
Because of the nature of a bay environment, Biscayne"s open waters are subject to conditions created by the coasts, open oceans, hurricanes, surface pollution, invasive species from below and wreckage on the ocean floor.
One of the biggest problems facing the bay is that of fresh water runoff, Taylor said. In the most basic sense, freshwater runoff is a fairly slow process through which 17 freshwater basins in the Everglades transport rainfall into the bay. This freshwater intake disturbs the saline balance in the bay, thus affecting the water quality and purity.
"The results include a decrease in salinity during peak runoff, which stresses and kills marine plants and animals, an increase in nutrients, which promotes algae blooms that smother sea grass and coral," Taylor said. "The pH also tends to drop as do oxygen levels, which is bad for both plants and animals as well."
The development of the land west of the bay has increased significantly in recent years and drainage systems have been heavily altered. Still, though the rainfall is filtered through wetlands and swamps, the current natural plumbing system in place allows for vast amounts of freshwater to enter the bay.
"Water quality has improved since the 1950s but there is still far too much freshwater entering the system," Taylor said. "Hopefully once the Everglades restoration is complete, this will be greatly curtailed."
The fresh rainwater is problematic in itself. However, as it flows through the basins and canals, it acquires various forms of debris and pollutants which in turn enter the delicate ecosystem of the Bay.
"Pollution is our contribution and hot weather generally makes pollution or its effects worse," Taylor said. "Moving debris in the Bay can seriously damage coral during storms as well."
Aside from curtailing our contribution of pollutants into the environment, Taylor said the infrastructure of the drainage system needs to be overhauled. The runoff could be prevented if all of the drainage canals were plugged and the water was rerouted back west to the Everglades. There are also things we can do on a personal scale to prevent runoff.
"We need to landscape our yards [properly to] prevent runoff, avoid irrigation, avoid fertilization and insecticides on lawns and make our communities retain as much runoff as possible through effective storm water management," Taylor said. "This water needs to go back into the aquifers because water shortages are the big looming crisis in all of Florida."
Taylor's final message is that these three environments must be protected and their ecology must be closely monitored to protect the fish and our way of life.
He offers concrete recommendations that everyone can follow to protect these fragile environments:
Marine Protected Areas are a good start, but must be better-enforced. Proper disposal of recyclables and garbage is also needed. Boaters should strive to be responsible with their dumping and in their navigation to protect the plants and animals. Still, the scientists know the most important ingredient will voter support for tougher MPAs and better regulations as well as education of everyone who uses and enjoys these delicate ecosystems.
