“It’s a nautilus,” chirps one of the youngsters, as our guide, Judy Dixon holds up a delicate shell for us to identify. “Well, not quite,” she replies. “It’s sometimes called a paper nautilus because of its paper-thin casing, but is actually the egg case of an argonaut, a pelagic octopus.” Sedgefield local, Judy delves into her treasure chest like a magician to produce another exhibit.
A moonlit meander
In the car park at Swartvlei Beach, at Sedgefield on the Garden Route, we watch enthralled as Judy, a retired biology teacher and marine fundi gives us a short introductory briefing, and produces clues to the marine life we might expect to see on the evening’s Starlight Stroll along the beach to the rock pools at Gericke’s Point.
“My interest in the marine environment was fired when I was at Cape Town University,” Judy says, as we wait for the party to assemble. “My zoology lecturer there, Professor John Day, was a world-renowned marine biologist. When I retired to the Garden Route 26 years ago I discovered the diversity of Swartvlei Beach, and realised it was the ideal venue to nurture my passion.
“I started leading walks to the Gericke’s Point rock pools on spring low tides [Moonlight Meanders and Starlight Strolls] about 20 years ago, when I was chairperson of Sedgefield WESSA [the Wildlife and Environment Society of South Africa], and decided to put the ‘fun’ into fundraising. I also offered the tours to other organisations such as the Botanical Society and pensioners associations, and they were so popular that, as demand grew, I was persuaded by friends to qualify as a tour guide, and became ‘professional’.”
We are a 15-strong group of enthusiasts aged between five and 65 years. Roughly half are Sedgefield locals, and the rest, including photographer Shaen Adey and I, are visitors. It’s my second tour with Judy, having joined her on a Moonlight Meander (at full moon) after completing her son Mark Dixon’s four-day Garden Route Coastal Trail.
That was more than a decade ago and I was eager to see how the coast and marine life in this ecologically diverse corner of the Garden Route had changed, and to explore the rock pools and intertidal zone under the new moon.
Silhouetted in the setting sun
Despite living in Knysna for more than 15 years, Caron Watson, with whom we are staying, has never been to Gericke’s Point so we arrive early for a beach picnic. There we meet up with Mark, a marine scientist keen to update us on the Strandloper Project, his latest conservation mission aimed at raising awareness of the damage that fishermen do by leaving hooks and line entangled in the reef. “I’ve been taking people on guided tours to Gericke’s Point, and teaching them about the marine life there, for more than 20 years,” Mark says.
“It’s my go-to point when I have spare time. If conditions are suitable I get into the water to study the marine life and to clean up snagged recreational fishing tackle. It’s one way of protecting this crucial marine ecosystem.”
Mark explains that since January 2018 he’s been involved with the Strandloper Project, studying the accumulation rates of snagged fishing tackle on a 100-metre transect. “Over the course of ten dives we recovered 650 lead sinkers, an astounding 6.5 sinkers per metre. The focus of the study is to determine the incidence of ghost fishing, whereby fish and, sadly, birds are entrapped not by fishermen themselves, but by hooks and monofilaments that have been snagged and abandoned on the rocks.” It’s a sobering scene-setter for the evening performance.
Fast forward a couple of hours and the sun is low in the sky as we follow Judy down to the beach, the reflection of pink and orange clouds lighting up the sand near the water’s edge. Silhouetted in the setting sun, Gericke’s Point resembles a slumbering lion.
“It’s so beautiful. I can’t believe I’ve never been here before,” says Caron, as we stop to watch plough snails trawling their way towards the remains of an unfortunate jellyfish. “Plough snails are scavengers, like vultures or hyenas, and are superb beach cleaners,” Judy says, picking up a fragment of the damaged jelly and flinging it towards the ocean. Immediately, sea snails can be seen converging on the treat. “Their incredible sense of smell allows them to locate food from a long distance.”
Crowding around the pools
Our next stop on the Sedgefield seafront is at a big boulder, home to a variety of marine organisms, including the unattractive pill bugs that roll into a tight ball when we disturb them. “Now you see where they get their ‘roly-poly’ nickname,” says Judy, as the children delight in picking up the scaly balls.
Nooks and crannies in the rock are covered with mussels. “Can you see the difference between the two sorts?” she asks. “The big, blue-black mussels originally came from the Mediterranean Sea, probably clinging onto the hull of ships. Since they are faster growing than our smaller, indigenous brown mussels, they’re taking over the latter’s habitat. So if you buy a permit and go musselling, please collect only the Mediterranean ones.”
As the first stars twinkle in the sky we pick our way across the intertidal zone to a deep rock pool, shining our torches into its inky depths to bring out the vibrant colours of its inhabitants. Orange starfish cling to the sides of the natural aquarium, while the tentacles of pink and purple anemones sway in the current. Every two weeks on the new and full moon, the unusually low tide exposes pools and canyons normally submerged, creating the perfect opportunity to observe the antics of nocturnal inhabitants in the gin-clear water.
Spreading ourselves out across the numerous natural pools, we start our vigil, calling Judy over to identify various molluscs, crabs, fish and other critters out on their nightly hunt for food. Identifying lots of juvenile fish, including great shoals of Sparidae and mullet fingerlings, and a tiny sea hare (Aplysia parvula), our passionate guide explains how these sheltered pools are where juvenile fish and other organisms learn essential survival skills.
“There,” announces Judy triumphantly. “Look at that pretty little crowned nudibranch (Polycera capensis). It’s a type of sea slug. And can you see the octopus?” The big-eyed, bulbous critter emerges from its lair, changing colour like a chameleon as it propels itself across the pool before resting on the sandy bottom. “Octopuses are fascinating, such intelligent creatures and wonderful mimics,” says Judy. “It’s always a privilege to see them in their natural environment. I’ve seen them in so many different hues.”
Enthralled, we crowd around the pool until an unexpectedly large wave has us backtracking. At our feet we see a large female octopus that, to our amusement, plays to the audience, crawling over the rocky ledge then reaching out with her tentacles to check our shoes, before Judy returns her to the pool.
After the elation of this, the sight of some freshly severed tentacles nearby is sobering. “Octopuses are often harvested for bait,” Judy explains. “We sometimes see fishermen hoiking them out, even though it’s against the law to collect bait anywhere along the coastline between sunset and sunrise. I try to make them understand how important these protected nurseries are in ensuring the marine diversity of our seas.”
The gently crashing waves
Caron is keen to know of Judy’s most unusual and special observations over the years. “Cuttlefish hunts are really exciting,” says Judy. “A few months ago we watched two tuberculate cuttlefish swim through the crystal water, ruffling their skirts as they sped after their prey. Suddenly two arms shot out from one of them and, in the blink of an eye, a tiny fish was caught and devoured.”
“Long-legged sea spiders, known as pantopoda (all legs) are another rarity I’ve only observed on four or five occasions. Marine arthropods belonging to the class Pycnogonida, they are fascinating to watch as they crawl over rocks and tread water in the pools. They move like robots, moving their multi-jointed legs like Michael Jackson.
“But probably the most thrilling sighting was of heart urchins, which live in deep burrows lined with mucus. Because they are buried it is very unusual to see a live one. I just happened to be in the right place at the right time. Mind you, I’ve seen dead ones. Once, when Knysna Municipality opened the wrong valve and fed sewage into the lagoon, I was inundated with phone calls about the ‘eggs’ washed up around Leisure Isle. They were the skeletons of heart urchins that live there.”
Judy insists that we return to Sedgefield in winter.
“In addition to all the young fish, sea stars and sea urchins we often see the bioluminescence of organisms. During metabolism, they produce light instead of heat so it looks as if the pools are sparkling. It’s quite something.”
Three hours pass quickly and the night is balmy and still as we walk back to the car park, listening to the sound of the waves and trying to identify the stars. It has been a fascinating adventure, filled with adrenalin of the chase and the complexity of life in the rock pools and along the shore.
In a Nutshell
Up to it? This easy walk of about four kilometres along the Sedgefield seafront takes roughly three hours. There is no age restriction on participants, but be prepared to walk on sand and slippery rocks.
What to Bring: A good torch or headlamp that will last for three hours, reef shoes or trainers that can get wet, and a warm jacket. Even in the height of summer it can get chilly after sunset. Binoculars are handy if you fancy a spot of stargazing.
You can download free apps, such as Skyview, onto your phone to help identify the various constellations.
Photos by Shaen Adey