After a fun week in Sanibel Island, my Florida adventure continues as I celebrate National Park Week (April 19–27) with a trip to Everglades National Park! 🐊🐍🦅
Sharon Lyon
Editor, GeoLifestyle
Sanibel Island, Florida
Taking in the sun and seashells at Sanibel Island
Sanibel Island is a barrier island on Florida’s Gulf Coast, known for its abundance of seashells. More than 350 species of mollusks wash ashore on the beaches. Why are the shells so plentiful? 🐚
Orientation and topography: Two main factors push seashells onto the beach.
While most barrier islands are oriented parallel to the coast, Sanibel is oriented east-west, perpendicular to the mainland.
Sanibel’s gentle, underwater shelf extends for miles out into the Gulf, unlike the extreme drop-off on the Atlantic Coast.
Seashell treasures: Commonly found are the Banded Tulip, Lettered Olive, Atlantic Calico Scallop, Lightning Whelk, Pear Whelk, Atlantic Giant Cockle, and West Indian Fighting Conch. One year we found a Junonia, a rare gastropod with a brown, spotted shell.
Trip tips: December through April are the best months to collect shells.
Blind Pass Beach (by thetiny inlet separating Sanibel from Captiva Island), Bowman’s Beach, and the beach at the Sanibel Island Lighthouse are perfect places to collect.
Head out at sunrise at low tide, especially after a heavy storm or during a full moon for the best shelling.
You must throw back any live shells.
Bring a net bag or bucket. You can buy a long-handled scoop, so you don’t develop the bent-over posture known as the Sanibel Stoop.
Wear flip-flops or water shoes because the shelly sand is hard on your feet.
Sanctuary Island: Conserved wildlands occupy 70 percent of Sanibel Island. Visit the J.N. “Ding” Darling National Wildlife Refuge, part of the largest undeveloped mangrove ecosystem in the United States.
Start at the Visitor and Education Center to see the exhibits on the ecosystems, the plants and animals, and the migratory birds.
Walk, bike, drive, or take a tram along the four-mile Wildlife Drive.
Be sure to stop at the overlooks and the three walking trails, including a walk to a Calusa shell mound.
Drive slowly—there can be alligator traffic jams!
The sanctuary is world famous for its spectacular migratory bird populations—more than 245 bird species live there! Favorites include white pelicans, cormorants, herons, egrets, spoonbills, and storks.
Binoculars are a must. Photography opportunities abound.
You can also walk or bike the Bailey Tract, a separate, interior part of the sanctuary.
The bottom line: Sanibel Island is still in the process of recovery after Hurricane Ian, which struck in fall 2022. Even so, I consider Sanibel to be one of the most exceptional locales in Florida.
A message from AAPG Academy and Viridien
Join AAPG Academy and Viridien on 6 May at 9am CDT to discover how to bridge the gap between powerful spectral tools and everyday geological workflows. This technology offers a fast, scalable, and low-risk way to gather insights, and has many geological applications beyond the mining industry.
Expert speaker Aflie Baines will be your guide to:
Understanding core concepts in spectral geology
A better understanding of how spectral results can inform a geologist's conclusions
Insights on how to evaluate whether a workflow in a peer reviewed journal is applicable to your project
Everglades National Park covers 1.5 million acres that extend over the southern portion of Florida. This south-dipping lowland is bordered by the Southern Atlantic Coastal Strip to the east and the Big Cypress Swamp to the west.
In addition to being a National Park, the Everglades is a UNESCO World Heritage Site, International Biosphere Reserve, and a Ramsar Wetlands of International Importance.
Flora, fauna, and ecosystems: Noteworthy ecosystems include freshwater sloughs, marl prairies, tropical hammocks, pineland, cypress, mangrove, coastal lowlands, marine, and estuarine.
Nearly 300 fish species, 17 amphibian species, more than 360 bird species, 40 mammalian species, and 50 kinds of reptiles live in the Everglades.
Thirty-six federally protected animals live in the park, some of which face grave threats to their survival: The Florida panther and four turtle species are endangered. The American crocodile and West Indian manatee are threatened.
Python problem: Invasive snakes, released by irresponsible pet owners, have proliferated, causing the number of mammals to decline sharply. The Burmese python is the most problematic. Each female python can lay roughly 100 eggs a year. Since 2017, the State of Florida has paid contractors to kill pythons year-round, but it is difficult to measure the success of the effort.
If you’re interested in learning more about hunting as an invasive species management measure, you can read about Mike Kimmel “The Python Cowboy.” His site is here. He has some wild stories about wrangling massive Burmese pythons.
Hydrology: Water flows south from the Okeechobee Basin in central Florida, traveling 100 miles down two sloughs to reach the outflow in Florida Bay.
The Shark River Slough and Taylor Slough are conduits of overland freshwater. The sloughs occupy areas of slight depressions in the limestone bedrock. Tall sawgrass growing in the sloughs gave the Everglades the nickname “River of Grass.”
The Rocky Glades region of the park is an area of karst that separates the Shark River Slough from the Taylor Slough. You can see solution holes in the karst, which provide refuge for aquatic animals during the dry season.
Manmade canals and levees, built to drain swamps for agriculture and development, have slowed the sheet flow of water from Lake Okeechobee, altering the steady stream of freshwater across the Everglades.
Trip tips: You can enter the park via three different cities and entrances: the Ernest F. Coe Visitor Center in Homestead, the Shark Valley Visitor Center in Miami, and the Gulf Coast Visitor Center in Everglades City.
Take a tram, boat, or airboat guided tour.
Camping, kayaking, hiking, fishing and biking are available.
Because of its remoteness, portions of the park are ideal for dark sky observing, especially around the time of the New Moon. The Milky Way can often be seen when looking south, toward the least light-polluted areas.
A few of the Doc Ford's books with the menu from Doc Ford's Rum Bar & Grille
Are you ready for a thriller? If you haven’t read the Doc Ford series by Randy Wayne White, start with Sanibel Flats (Book #1) and work your way through One Deadly Eye (Book #27). White expertly weaves his knowledge of the fauna and flora, history, meteorology, and geology of south Florida in each book.
The plot: Dr. Marion Ford lives in a stilt house in Dinkin’s Bay, a quiet marina on Sanibel Island. A marine biologist, Doc Ford runs a one-man company, supplying marine specimens to researchers. But beneath his mild-mannered façade, Ford is an undercover government operative with a special talent for solving problems.
👍 If you enjoyed this edition of GeoLifestyle, consider supporting AAPG's brand of newsletters by forwarding to a friend or colleague and signing up for our other newsletters here.
➡️ Was this newsletter forwarded to you? Sign up for GeoLifestyle here.
AAPG thanks our advertisers for their support. Sponsorship has no influence on editorial content. If you're interested in supporting AAPG digital products, reach out to Melissa Roberts.
