Healthy Water Makes Healthy Marine Life

http://www.nytimes.com/2013/08/08/us/deaths-of-manatees-dolphins-and-pelicans-point-to-estuary-at-risk.html (link to article)

The article “Deaths of Manatees, Dolphins and Pelicans Point to Estuary at Risk” by Michael Wines can be found in The New York Times and was published on August 7, 2013.

There has been a startling amount of deaths of marine in Florida's waters. It is feared that these under water environments are crumbling under the strain of years of pollution caused by Florida's 

rapid development. Brevard, on the Banana river,  is a focus of this development because of it’s 

many motels lining the beach, canal front tract homes, and even a golf course in the middle of the Banana river. Because of all of these attractions the bodies of water off Brevard are at a higher risk of pollution.

As said in the article “Death of Manatees, Dolphins and Pelicans Point to Estuary at Risk”, “Surveys in 2011 and 2012 by the Harbor Branch Oceanographic Institute at Florida Atlantic University concluded that estuary waters off Brevard contained 45 percent more nitrogen than is acceptable” It is devastating to hear that these large numbers of pollutants are in Florida's waters and it is because of Florida's development. This polluted water needs to be cleaned up so marine life can have a healthy environment. The source of this nitrogen is not definite but it is hypothesized that it came from sewage.

Algal Bloom

An estimated 100,000 septic tanks were put in during the expansion of Brevard. If a sewage pipe leaks it can release nutrients into the water, nitrogen. So, because of the increase in the number of septic tanks the amount of nitrogen released into Brevard’s bodies of water increases. Another big contributor to the high amounts of nitrogen in the water is from fertilizer (which is high in nutrients) runoff. As I stated above, there is a golf course in the middle of the Banana river. Golf courses are very big users of fertilizers because they want to keep their grass growing and looking good. This fertilizer makes the grass look good but not the river. When it rains this fertilizer is washed away, right into the river adding the the nitrogen in the water.

Tiny organisms called phytoplankton use this nitrogen in the water to photosynthesize, creating food(energy). There is so much nitrogen in the water and the phytoplankton continue to use this nitrogen so the phytoplankton grows rapidly. This rapid growth of phytoplankton is called an algal bloom. Experts suggest that heavy rainfall in 2011 caused the algal blooms in Florida's waters. This is because more rainfall means more runoff water that will carry nitrogen into the bodies of water.

These algal blooms can be harmful to the other organisms in this ecosystem. The phytoplankton need to perform photosynthesis in order obtain energy because they are autotrophs, meaning they make their own food. Large amounts of oxygen is being taken from the water because so many phytoplankton are performing photosynthesis. The oxygen is the water is being depleted and this can 

result in hypoxia, meaning there is low levels of oxygen in the water, or anoxia, meaning there is no oxygen in the water. This means that other organisms like fish do not get the necessary oxygen they need to survive.

Now, you might ask what this has to do with the deaths of manatees, dolphins, and pelicans. Scientists studying these deaths say they are puzzling. One of the best clues to this puzzle is the seaweed that replaced the sea grass of the body of water. The manatees seemed to be in good health when they died. But the scientists found out that, as said in the article, “The sole exception was their intestines, which showed evidence of severe shock or irritation. Autopsies showed that the stomachs of all three manatees were filled with macroalgae, mostly a fanlike seaweed called gracilaria.” They concluded that this macroalgae played a role in the deaths of these manatees. Although the reason they died is not definite yet the scientists are on their way to figuring out this marine life mystery.

It is very plausible that the reason for the sea grasses replacement by seaweed was because the seaweed flourished because of the large amounts of nitrogen in the water (like the phytoplankton). The seaweed might have flourished more that the sea grass and the seaweed seized control of resources in the water and left the seagrass with not enough to survive. When the manatees ate the gracilaria (fanlike seaweed) their intestines were irritated by this new food.

It is also logical that the dolphins and pelicans died because the fish were not getting enough oxygen (because the phytoplankton was using it up in photosynthesis) and were dying off. This leaves the dolphins and pelicans with not enough food and they will die off as well.

Dolphin in Banana River

Previously in biology class we learned about how runoff water and sewage pipes can cause nitrogen to get into bodies of water. Also how this nitrogen can cause lots of problems, like algal blooms and hypoxia. This article is a great real life example of the problems nitrogen in the water causes.

I believe that this is an important topic that should be recognized and changed. When I went to Florida over vacation last year I went on a dolphin tour and saw lots of dolphins in their natural habitat. I would like future generations to have the opportunity to have that experiences but in order for that to happen we need to cleaned up bodies of water in order to keep precious marine animals happy and healthy.   

Photo citations:  1. http://www.dep.state.fl.us/coastal/sites/banana/

2.  http://www.daviddarling.info/encyclopedia/A/AE_algal_bloom.html

3. ww.tripadvisor.com/Attraction_Review-g34145-d2055825-Reviews-Wild_Side_Tours-Cocoa_Beach_Florida.html