There is an Ocean Tribe of Sanibel Sea School that extends more than 5,000 miles across the globe! Even though we all hail from different parts of the world, we have one connection that binds us: a love for our oceans. During the holidays, we had the opportunity to come together and delve into the concept of home ranges and discover, or rediscover, many of our favorite sea creatures.
Biologists define home range as the total geographic area used by an individual during its lifetime. Some animals have small home ranges, and some have enormous home ranges. But, all animals have some defined geographic space where they spend their lives – there are no true wanderers. A combination of all the individual home ranges of a species is known as the species range. During our holiday camp, we explored these two concepts.
We also explored the ecological concept of philopatry, or the tendency of an animal to stay in, or return to its birthplace. We learned about the astounding behavior of sea turtles and their ability to navigate the open ocean using an internal compass, returning to an area year after year. Our campers explored how sensory systems in marine animals are a vital tool in navigating unfamiliar places. We learned that hammerhead sharks utilize seven senses, including electroreception and a lateral line system to locate prey and read the surrounding environment. Campers even donned special masks to simulate binocular vision in hammerheads to gain a first-hand look at what this shark sees.
We braved chilly Gulf waters all week long and practiced navigating the open ocean on surfboards with daily surf lessons. Campers honed their navigational skills by utilizing compasses to guide their way through, and make maps of the Bailey Tract. We also observed many Ospreys along the way, which are highly philopatric. When we weren’t being master orienteers around the island we were busy seining, throwing cast-nets, and investigating sea grass beds. We discovered that seining for fish is similar to the cooperative behavior of Atlantic bottlenose dolphins, working together to herd fish into a smaller area for feeding.
We created a large group art project to visualize our home range by marking our hometowns on a global map. Each hometown was illuminated and the map will be displayed at Sanibel Sea School to visualize our ‘species’ range. We learned how vast our home ranges were, but that begs the question: what actually makes a place a home? We often think of three things when it comes to home: safety, comfort, and love. These qualities are core to Sanibel Sea School.
We started off the New Year fresh, offering our troubles from 2013 to the sea. Campers wrote down their struggles on a small slip of paper and we collectively burned them. We offered a pinch of the ashes of our burdens to the sea, allowing the tide to wash them away for us, wiping the slate clean for 2014. Even though we were all at the limit of our home ranges for this holiday season, we all found safety, comfort, and love here on Sanibel Island together.