Science in the swamp: Exploring the biology of mangrove estuaries via kayak
However much you know about mangroves, wetlands, and estuaries, when you return from a Rising Tide Adventures kayaking excursion, you will know more.
On a morning tour of the watery landscape that separates Marco Island from the mainland, paradoxically on a falling tide, in addition to absorbing the beauty and stillness of the brackish water habitat, the guests received what amounted to an intensive biology workshop, conducted in nature’s open-air science lab.
The group on the “mangrove tunnels and mudflats” tour got some of each, sometimes having to squeeze themselves through and under mangroves, or having the chance to stand in the shallow water and examine specimens such as transparent comb jellies and mangrove tunicates, a proto-vertebrate which has been utilized to create a cancer-fighting drug – shades of the ubiquitous “originally found in jellyfish” TV commercials.
Rising Tide is a kayak outfitter with a mission, beyond simply putting paddlers in boats and shoving off. The company was formed by a former Florida Department of Environmental Protection (DEP) biologist, Ryan Young, who worked at Audubon’s Corkscrew Swamp Preserve, monitored sea turtles at the Rookery Bay Reserve, and studied fish populations in the Picayune and Fakahatchee strands.
As tour guides, he has brought on fellow biologists, each with their own areas of expertise, and each eager to share the wonder and importance of mangrove estuaries to the creature at the top of the food web, homo sapiens. Earlier this year, Rising Tide became the exclusive boat tour partner of the Friends of Rookery Bay.
Along with Young, our guide on Sunday morning was Samantha Troast, who is working for DEP while finishing up her master’s in biology at FGCU. She specializes in the study of diminutive blind snakes but extends her knowledge to the creatures of the estuary.
These include both the well-known, such as manatees, bottlenose dolphins, ospreys and great egrets, all of which showed up for the tour, and the “keystone species” of the estuary, the eastern American oyster, which literally build the foundation of the mangrove swamp.
The group of seven kayaks paddling from the Isles of Capri Paddlecraft Park on a comfortable-for-July morning stopped periodically for the guides to point out some of the local inhabitants.
Each individual oyster, said Troast, can filter 30 to 50 gallons of water per day. So, the cluster of about 20 oysters she scooped up from the waist-deep water could cleanse something over 600 gallons that day – and there are millions of oysters throughout the estuary.
The guides also spoke of how mangroves, which along with the oysters are the backbone of the local ecosystem, provide spawning grounds for a myriad of fish species, stabilize the land, give live birth through their propagules, and manage to excrete salt through their bark and leaves, allowing them to thrive in a place where no other tree could grow.
Troast also displayed one other species, near and dear to many locals’ hearts, holding – carefully – a young stone crab, highlighting another of the many benefits the estuary provides. Two other noted local species, the salt marsh mosquito and no-see-ums, were mercifully absent, with no need for the insect repellent people brought.
“I’ve driven down 951 ten thousand times,” said Cub Scout leader Jason Sutliffe, who often works on Marco Island. “It’s amazing how different you see it after these guys show it to you from the water.”
“It’s just so peaceful and quiet,” said fellow Cub Scout leader Rebecca Jaen, who like Sutliffe was on a break from three children. “Being out here was great.”
One added feature of the tour was a selection of high quality photos shot by Troast, showing each kayaker their trip, and all downloadable at no charge from the Rising Tide Adventures website. For more information, to view kayaking photos, or to book a tour, go online to risingtidefl.com, or call 239-734-3231.