What Does “Fertilizer Free for Manatees” Mean?


The Save The Manatee Club, whose home base is located in Maitland Florida (just outside of Orlando Florida) has launched yet another initiative to help save the manatee: The “Fertilizer Free for Manatees” project.

Now, before we get into the details of this initiative, if this is your first time on this website, welcome! Here at Aquapparel we do not just regurgitate catchy headlines and leave out the stories that led up to a specific conservation win. We give you the background on what the initial issue is, what causes that issue to occur, what this organization is doing to help combat this issue and what you can do in order to help. First let’s jump into a brief history of manatee conservation.

A Brief History of Manatee Conservation

In 1972, the manatee was placed under the Federal Marine Mammal Protection Act. While efforts to protect and conserve this species started in 1967, we have come a very long way in understanding the key things that negatively impact this species.

For example, boat strikes are one of the most common issues that negatively impact the manatee. In order to combat this issue, FWC (Florida Fish and Wildlife) enacted protection rules that restrict the speed and even the complete operation of marine vessels where these strikes mainly occur in order to reduce injury from boat strikes.

Another pretty serious issue that affects all marine life to varying degrees is algal blooms. These blooms contain toxic species of algae that are known to destroy vegetation in marine environments as well as affect the food chain – tainting it with toxins. Some species can even make humans sick if they are exposed to them. Next, let’s learn how these occur in the first place.

What Causes Algal Blooms?

In the wild, algal blooms are caused by an excess of nutrients – more specifically phosphorus and nitrogen. Phosphorus and nitrogen are by-products from any kind of practice that involves excess fecal material. For example, fertilizer from farming, as well as sewage, converts into phosphorus and nitrogen.

Normally, plants and small animals help to combat and consume these elements. However, when there is too much phosphorus and nitrogen in the water, this creates a breeding ground for HABs or Harmful Algal Bloom species. The species that we deal with in Florida that directly impact the manatees are Karenia brevis and Microcystis aeruginosa cyanobacteria.

Karenia brevis is commonly found on the west coast of Florida and Texas in the gulf. This species of algae produces a combination of potent neurotoxins collectively called brevetoxins. These brevetoxins can cause gastrointestinal and neurological issues in all kinds of organisms and are responsible for large die-offs of marine organisms and seabirds. Microcystis aeruginosa cyanobacteria is a freshwater species of bacteria that causes toxic algal blooms. It is the most common species and it is found world wide.

As the excess nutrients accumulate into a body of water, the plant life starts to die off. This creates the perfect breeding ground for Karenia brevis and Microcystis aeruginosa cyanobacteria. Once the algae bloom starts to take over, all kinds of marine life and even terrestrial animals that consume the marine life start to get sick and die off. So how do we prevent these algal blooms from happening in the first place?

Quick Aquarium Science Lesson

A lake or ocean is considered to be an open system. An aquarium, however, is a closed system. In an open system we need much more resources in order to right a wrong so to speak. In an aquarium, however, we can right wrongs using a number of solutions. And this is how we figure out what to do in open systems in regards to preventing issues as well as resolving them.

For example, algae bloom in your aquarium? This means that you are either:

  • Witnessing the aquarium’s Nitrogen Cycle (excess nutrients)
  • Overfeeding your fish (excess nutrients)
  • You can too many fish in your aquarium (excess nutrients)
  • Your aquarium’s biological filtration system is not large enough to handle your aquarium’s bio load (excess nutrients)

Are you starting to see a trend here? Excess nutrients = Not a good time. In a closed system like an aquarium, you can reduce the amount of excess nutrients by allowing the nitrogen cycle to run its course. To do this, you simply do not add anything that will increase the amount of excess nutrients to it. I.E.  have less fish, reduce the amount of food being added to the aquarium and/or you can increase the biological filtration, doing so will help to eliminate the algal bloom.

In an open system, this feat is a bit more complicated. Usually what happens is the excess nutrient source is identified and cut off or significantly reduced in order to allow the body of water to recover. Without the excess nutrients, the Karenia brevis and Microcystis aeruginosa cyanobacteria will die off. From there, life – as it always does – will find a way and the plant life will start to grow back. Once that grows back, the small organisms come back to help maintain the plant life, bigger marine species then come to keep those populations in check and so on and so forth.

The best solution to this problem and the way to prevent this from happening in the first place is to prevent excess nutrients from entering marine habitats to begin with. This is where the Save the Manatee Club steps in with their new initiative.

Fertilizer-Free for Manatees

The Save The Manatee Club launched a new project called “Fertilizer Free for Manatees”. This project’s goal is to teach Floridians how to reduce excess nutrient output and run off. Here are the 3 ways that you can help to reduce excess nutrients with your own lawn:

  • Avoid fertilizer use on your lawn if you live on or close to the water
  • Conserve water by watering your lawn only when necessary
  • Keep grass clippings off of the streets, bodies of water and swales

You can learn about Florida-Friendly Landscaping from the University of Florida’s IFAS Extension’s full guide that will teach you everything you need to know here: Florida Friendly Landscaping. You can even ask an expert in this section of their website:

If you are a Florida resident and you are interested in taking the pledge, visit the Save the Manatee Club’s Fertilizer-Free for Manatees page here: Take The Pledge

Learn more about the Save the Manatee Club on this episode of Aquapparel TV here:

For more good news about conservation wins like this one, check out the Conservation Wins section of this website here: Conservation Wins

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