Bonnethead Sharks or Sphyrna tiburo are the smallest member of the hammerhead family that can reach up to 4 feet long. They are an amazing indication here in the low country that summer has arrived! The once quiet salt marsh is now full of bonnethead sharks that can be found feeding on a variety of crustaceans and small fish during low tide near the exposed mudflats. Although these sharks are mostly carnivorous, they occasionally eat plants such as seaweed or seagrass making them omnivores unlike their other hammerhead family members.

 

But, just like other hammerhead sharks, the bonnethead shark has an odd, shaped head that distinguishes them from other shark species. They have a unique shovel shaped head that allows them to make sharper turns and have a wider range of vision when hunting for prey. Not only are their heads different than other shark species, but they are the only known species of shark in the world that you can distinguish females from males based on their heads. Female bonnethead sharks have a smooth round head compared to the males who have a bulge on their head. Recent research has also suggested bonnethead sharks are sensitive to the earth’s magnetic field and likely utilize it during migration to navigate from deep waters in the winter to shallower waters in the summer.

Like dolphins, these sharks also travel in groups of up to 15 but have been seen in the thousands during migration! Bonnethead sharks also excrete cerebrospinal fluid that informs other sharks nearby of their arrival. Bonnethead sharks are a unique and amazing animal that has been listed as an endangered species since 2019 due to overfishing by small scale fisheries. To see these awesome sharks in person join us on a guided boat or kayak tour or enjoy them on your own adventure by renting a kayak or paddleboard!

Post by Ally Jo Salomon (Naturalist Guide)

Osprey are raptors found around nearly every body of water. Some may even migrate great distances in pursuit of ideal habitat. Perched or flying above rivers, ponds, reservoirs, coral reefs and here throughout the lowcountry; our salt marshes. Their simplistic stick nests can be found in dead trees, on man-made osprey platforms and even using channel markers as foundations. The nests are most often positioned in wide open spaces, often right over the water. They are visual hunters who use open perches or flying in their unmistakable M shape to scan the water for fish using their incredible eyesight.

Osprey eyes have four types of color sensors compared to our three, this allows them to perceive ultraviolet light along with the light visible to humans. Along with binocular vision they have an amazing peripheral field as well, giving them a wide range to the sides. Osprey also have dark feathers surrounding their eyes to reflect the sun’s glare bouncing off the water. Even more advanced is their calculation of the refractive index. Determining exactly how deep prey is as water depth changes the angle a fish might appear from above vs under water. Scientists even think they can ‘see’ the earth’s magnetic field which allows precise navigation over long migrations. An osprey’s right eye contains specialized proteins which are thought to perceive the earth’s magnetic fields.

Like most birds of prey, an interesting way to determine the age of an osprey is to look at the color of their eyes. They are born with dark blue or black eyes and after a few days the eyes will change to an amber color. Once the youngsters fledge they typically head on a migration all the way down to South America, amber eyes and all. When they return north after 1.5-3 years, they return with amazing bright yellow eyes, marking them as mature and ready to breed!

Post by Matt Luzon (Captain)

“Messenger,” (1-5)
My work is loving the world.
Here the sunflowers, there the hummingbird—
equal seekers of sweetness.
Here the quickening yeast; there the blue plums.
Here the clam deep in the speckled sand.
Mary Oliver (2006)

Looking out from the bow of the boat, the horizon stretches low. Treeline strings along the horizon, where the channels and creeks do not extend. Coming from the sea islands, the salt marsh has a refreshing and minimal appearance. Vibrant green cordgrass, a moody grey sky, mist in the air. Clean and simple lines are made by the distant islands, the water and the sky, as well as the estuary grasses that meander along. White phantom-like egrets rise from the grass. Beautiful white feathered wings unfurling, their flight arching overhead, or gliding above the water. This area is punctuated by the occasional bridge, connecting the developed islands to one another.

Arriving at the St. Phillips, the scenery transforms. Setting forward on mostly undeveloped land, we move from the dock, and into the canopy of the climax maritime forest. Near the water, there are sparse trees that gradually descend into a old complex forest. The plant life here feels loud, leaves of varying sizes and shapes zig-zag across one another. Soft spanish moss lazes down from the trees, bright pink bubblegum lichen speckle the trunks. Vibrant and lively, the contrast from land to barrier island is polarizing.

Wind and water must have formed this land. This is the Coastal Plain of South Carolina, the majority of the land sits at 270 feet above sea level. Also known as the Lowcountry, this unique region was formed from the powerful rise and fall of the sea level, eroding over time. There seems to be an advantage to unique shapes in nature that can work with the wind, rather than be destroyed by it.

Salinity has a huge influence over the plant density and types. This can interfere with a plants ability to uptake nitrogen, and reproduce. So, in the estuary the few plants able to tolerate high salt levels live in or boarder the marsh waters. As we moved inland the biodiversity seemed to increase thanks to the lower salinity, and protection from the extreme conditions that storms can create. Focusing on abiotic forces leaves me with the sense that the elements have set the current stage, which is one of many in a long epic story.

Experiences like this have begun to change how I approach my daily life. Suddenly, almost everywhere I go becomes a place that can be read like the marsh, with the right amount of curiosity. Indicator species can clue us in on the health of areas. Geology of a space hints at unrecognizable landscapes from different times. This inspires my curiosity, not just about science, but art as well. Many mediums and individuals have tried to express the awe that being a part of the natural world makes us feel.

“Swan”
Did you too see it, drifting, all night, on the black river?
Did you see it in the morning, rising into the silvery air –
An armful of white blossoms,
A perfect commotion of silk and linen as it leaned
into the bondage of its wings; a snowbank, a bank of lilies,
Biting the air with its black beak?
Did you hear it, fluting and whistling
A shrill dark music– like the rain pelting the trees– like a waterfall
Knifing down the black ledges?
And did you see it, finally, just under the clouds –
A white cross Streaming across the sky, its feet
Like black leaves, its wings Like the stretching light of the river?
And did you feel it, in your heart, how it pertained to everything?
And have you too finally figured out what beauty is for?
And have you changed your life?
Mary Oliver 2010

Post by Emily Brazier (Naturalist Guide)

The barrier islands of the South Carolina lowcountry are a charming and important geological landform. Situated directly in contact with the Atlantic ocean, barrier islands protect more proximal sea islands and the mainland from high energy storm cells. Unlike sea islands, barrier islands are in a perpetual state of change. In fact, they can change by the day, and on St. Phillip’s island, the beach drop off point is where this daily and weekly shift can be seen most immediately. My previous trip out to the island stunned me by how different the beachfront looked compared to the last time I saw it, about 2 weeks before. Every time I visit, more and more debris accumulates on the high tide line bordering the beach trail. But, despite this frequent physical metamorphosis, the island takes on a fairly lonely role as being one of the last pristine safe havens for migrating and nesting seabirds and shorebirds along the coast of South Carolina.

I walked south towards the southern tip of the beachfront. On this particular day, the tide was extremely low, exposing vast areas of sand flats that aren’t normally visible. It was a bright, sunny morning with not a cloud in the sky, the smell of salt was heavy on the air, and I had one goal: to get a good view of the seabirds taking advantage of the exposed sand flats to rest and forage.

The exposed sand flat behind the large congregation of seabirds.

To my pleasant surprise, I was able to make out every single species of tern off the lowcountry coast at that time, in addition to many other species and a large group of my favorite seabird: the black skimmer. This bird is beautifully unique, and exhibits a really interesting foraging technique where they fly extremely close to the water’s surface with their lower mandible skimming for fish. Upon contact with a prey item, the bird quickly shuts their large, black and orange bills. The bill is actually a great way to identify them, as they seem to have a large underbite.

A small portion of the black skimmers seen. One can be seen laying completely down, which is done to cool off in the heat.

Seeing this sparked in me a sense that I was witnessing a rare congregation, a feeling that I was lucky to see such an aggregation of seabirds. And in part, I was. Habitats such as the exposed sand flat with little vegetation around and not a single man-made structure in view are quickly disappearing. The majority of barrier islands here are now developed, and are continuing to have more homes and municipalities spawn. With that comes a double edged sword that is detrimental for birds like the black skimmer: habitat loss and human disturbance. Each edge has worked to cut the black skimmer population down about 87% in 49 years of surveying. The skimmer is particularly sensitive to disturbance, especially during nesting season (May through July). If disturbed during this time, nesting mates quickly abandon eggs and do not return to continue incubating. This is why the majority of the recorded skimmer nests occur on protected islands where disturbance is prohibited, such as Cape Romain National Wildlife Refuge.

The low tide line where numerous whelks, clams, starfish, hermit crabs, and horseshoe crabs were found.

No matter the beach you visit this summer, you can do your part in ensuring birds like the black skimmer can nest successfully. Keeping dogs on their leashes, giving large groups of birds a wide berth, and avoiding the dune areas are all ways you can help protect such magnificent birds. Come visit St. Phillip’s with us to witness one of the last remaining southern safe havens.

Post by Eric Ng (Naturalist Guide)

Marsh tackys are a rare breed of colonial Spanish horse that is only found in the Lowcountry of South Carolina. They were brought here in the 1500s by Spanish explorers, but when those expeditions failed, they were left here and adapted to living in the salt marsh estuary that surrounds the islands of Beaufort County. These adaptations are seen in their thick skin and solid hooves that allow them to traverse a variety of landscapes and fend off gnats and mosquitoes found in the depths of the maritime forest. There are approximately 400 tackys left in South Carolina and the small herd that lives on Horse Island can sometimes be seen from a distance from our Basecamp on St Helena.

Want to see these horses yourself? Rent a kayak or paddleboard to plan your own expedition today! If you’d like a little more guidance, check out our 2-hour St Helena Kayak Safari that starts on May 1.