Blog Number 2; 4/30/2021; Aquatic Guards

 

The Everglades is a combination of four major impacting ecosystems, being forests, swamps, marshland, and reefs. Each of these ecosystems has a unique set of creatures, from the bears of the forests to the terrapins of the marshland. The Everglades is surrounded by many habitats where fresh and salt water are prevalent. The water, both fresh and salt, is the driving lifeforce of this magnificent paradise. It provides some animals with food, some with transportation, some with homes, and some with breeding grounds. Therefore, it is crucial to make sure the water is healthy. The best way to tell this is from the two mammalian kings of the waters. The dolphins of the reefs, and the manatees of the marshland.

Bottle-nosed dolphins are a top predator of the reefs, hunting everything from mullets to crab to squid, and occasionally young hammerhead sharks. Similar to the panther, dolphins make sure the prey animals do not get overpopulated. An easy way to tell the health of a dolphin is by the behavior of it and the fellow pod members. Often, if there is a sick or injured dolphin, the rest of the pod will preform a protective barrier around it while helping it stay afloat. If more than one dolphin is seen doing this, it means either they encountered a great white shark (who rarely hunt dolphins), or a disease is spreading through the pod. Top predators often get diseases from animals lower on the food chain. If the bottom of the food chain has a transmitted disease, it makes it easier to hunt. This starts a chain reaction that can travel through the entire food web. Dolphins of Florida have developed a unique way of hunting. This involves swimming circles around their prey, catching the prey in an aquatic sandstorm. The fish will then try to jump to escape the sandstorm, landing straight in the mammal’s mouth. New hunting techniques often are signs of a changing ecosystem. The dolphin is the most adaptive of all marine mammals within the Everglades, meaning if a sudden change in the ecosystem occurs, it could threaten other species.

The Florida manatee is a slow moving, gentle giant. They can often be seen eating aquatic vegetation in fresh water, and occasionally in salt water. However, being slow moving has its disadvantages. Manatees can be seen with white lines on their back and tail. This is a sign of having a harsh encounter with a boat. Manatees do not have time to get out of the way when jet boats speed through the bays and shores, causing them to either be seriously injured or killed. If manatees have a surplus of scars or boat related deaths, it means laws have to be put in to place to protect these aquatic mammals. Manatees also have a habit of preferring warm water over cold water. This can be seen best demonstrated at the Manatee Viewing Center in Apollo Beach, Florida. This viewing center has been constructed near where a powerplant meets the bay. The powerplant radiates warmth into the water, causing a large aggregation of manatees. Unlike whales, manatees do not have the blubber to keep themselves warm, so they end up searching for warmer waters to inhabit. With warming seas, spots like this might begin to show up naturally. This causes us to pay close attention to the number of manatees in an area when it is not the breeding season (March to November). Manatees also help control the marine plant population. On average, an adult manatee will feed on two-hundred pounds of sea grasses and other aquatic plants daily. If a marsh or bay is abnormally abundant in plant life, it could mean there is a lack of manatees in the given area.

At first I tried searching for scholarly articles on why manatees tend to stay in warm waters. This lead me down multiple studies where I could not find the exact topic I was searching for (although it did lead me to how manatees effect oxygen levels). After much struggle, I went back to old reliable, The Florida Fabulous Wildlife book series. This series is the most comprehensive Floridian wildlife encyclopedia that I can find. Shocking to no one, I found it immediately as well as the powerplant where it is viewed the most. The reason I go to these books last in my research is because I always have them, and do not have to look hard to find information. I would rather find some specific information that helps explain some knowledge on the animal I have, and then go to the books to see how it connects to the ecosystem.

Both bottle-nosed dolphins and Florida manatees help control aquatic wildlife populations. They are the guards of the water, making sure everyone stays in line. If an absence of dolphins were to occur, the squid population would bloom, causing a shift in ocean power and food availability. As with manatees, in their absence an overpopulation of sea grass would occur, causing the water to be less rich in oxygen. These two marine mammals help make the waters safe for their neighboring species. In order to keep the tab on the fresh and salt water ecosystem health, you need to keep a tab on the manatee and dolphin population health.