Southeast Volusia Audubon Society, P.O. Box 46, New Smyrna Beach, FL 32170;

March 2018 Conservation Notes

The Mosquito Lagoon/Indian River Lagoon: The Precautionary Principle

The precautionary principle states that “if an action or policy is a suspected risk of causing harm to the public, or to the environment, and there is absence of scientific consensus that the action or policies are harmful, the burden of proof that it is not harmful falls on those taking action that may or may not be a risk.” [Wiki] This principle should obtain immediately for any development that impacts the watershed of Mosquito Lagoon/Indian River Lagoon, an estuarine environment which was once a stable eco-system where abundant species of vertebrates and invertebrates could thrive in living waters.

Today, this body of water is nearing the redline as far as its ability to support an abundance of ecosystems is concerned. And, as the life in these waters is threatened, so is the physical health and the Quality of Life of those human beings living on or near this estuary, or using it for recreational purposes. [Who can forget the image of a family wakeboarding through lagoon waters south of Cocoa Beach that were the color and thickness of pea soup?] Just recently, the water to the south of Mosquito Lagoon, the Banana River, has seen a brown algae bloom.  This bloom was reported in “Florida Today” [March 02, 2018]:

Just when you thought that the Indian River Lagoon might be getting a little better, it's back: the brown algae that kills fish by the thousands is blooming, foreshadowing more doom for the troubled ecosystem.

State biologists say the same algae responsible for the 2016 fish kills — the worst on record — is growing at similar levels again.

"The cell concentrations that we've had in February have been actually quite similar to the cell concentrations in 2016," said Ed Phlips, a professor of algae physiology and ecology at University of Florida.

When algae cell concentrations reached comparable levels in 2016, the algae depleted oxygen dissolved in the water, suffocating fish by the thousands. Fish carcasses filled entire canals in Cocoa Beach.

Biologists began tracking the "brown tide" algae in January — unseasonably early. While, they say, it is less extensively distributed than it was two years ago, they are worried that its appearance so early in the year is a warning sign that another large-scale fish die-off is imminent, especially as temperatures in the lagoon rise and the algae growth explodes.

Kayakers paddling the lagoon are already reporting that the water resembles an olive-brown soup. They said they can't see the bottom, let alone the fish or manatees that pass within feet of their boats. Both paddlers and property owners alike fear what is coming if the algae goes on growing like this…. 

Some people said they couldn't remember when the lagoon wasn't brown. Others lamented the days when dolphins and manatees were visible beneath a clear lagoon surface. The days of crystal clear water and sandy bottom may not return for decades, biologists warn.

"People are looking for some immediate response," said Duane DeFreese, executive director of the Indian River Lagoon Council, which oversees lagoon cleanups. "It took Tampa Bay 25 years to recover."

The main algae at play these days — Aureoumbra lagunensis — first showed up in lagoon water samples in 2005 and first reached bloom concentrations here in August 2012.

Now, the algae, mixed with several other algae species, spreads over much of the Banana River, especially between State Roads 520 and 528. None of the algae species are known to be toxic, Phlips said, but pointed out that they still kill fish. The shape and amount of algae particles in the water can clog up the gills of fish and shellfish, such as oysters and scallops, and suck up all the available oxygen in the water, suffocating marine life.

Satellite images of the lagoon's current algae blooms even resemble similar images from the spring 2016 algae blooms. The images show levels of chlorophyll — an indicator of algae blooms — remain high in much of Brevard's portion of the lagoon, due to the mix of single-celled algae, mostly the species responsible for brown tide….

[Note:  Satellite images from the area taken during the last week in February show algae numbers above 140 g/L.  Over  4 g/L is considered high.]

During daylight, algae produce oxygen through photosynthesis, replenishing oxygen levels in the water. But at night, the algae consume oxygen. This, coupled with the normal demand for oxygen from fish, crabs and other marine life can cause dips in dissolved oxygen in the lagoon, with the lowest levels just before dawn.

Brown-tide and other algae blooms block the sunlight that seagrass needs to photosynthesize.

Seagrass is the keystone of the lagoon food web. It's the manatee's main diet. Mutton snapper, lane snapper, gag and red grouper, spotted sea trout, blue crabs and other marine life depend on seagrass for habitat. Studies have shown one acre of seagrass can support as many as 10,000 fish.

Seagrass loss in recent years has boosted the potential for brown tide blooms, Phlips said, because it stabilizes sediments that can stir up and make nutrients available to fuel excess algae. "Because the seagrass communities have suffered a lot ... when there's any kind of rainfall and external nutrient loading, then you're going to have an elevated potential for blooms."

The precautionary principle “implies that there is a social responsibility to protect the public from exposure to harm, when scientific investigations find plausible risk.”  One of the guiding principles that was produced by the Rio conference in 1992 [aka The Earth Summit] stated: “In order to protect the environment the precautionary approach shall be widely applied … Where there are threats of serious or irreversible damage, lack of full scientific certainty should not be used as a reason for postponing cost-effective measures to prevent environmental degradation.” 

The argument from our legislators and officials for not applying municipal and state rules and conditions that would immediately limit or reverse harm to the waters of the IRL system (e.g. a moratorium on new septic systems within 200 feet of any waterway) is that “more studies are needed.”  This has become a constant refrain among those lawmakers that are tasked with safeguarding our environment but who seem to always yield to the interests of developers and state and municipal officials whose motto is “Growth At Any Cost.” For example, one of our local House members recently sponsored a bill that would require a four-year study of the central Florida springsheds before any type of new springs protection legislation could be put into effect, including limits on septic systems.

The ancient Hippocratic oath included a section about “doing no harm” as a central principle of those in the healing professions.  Perhaps a version of this oath directed toward safeguarding  the residents and the eco-systems of Florida could be included in the pledge required of all our State legislators before they assume office.