Coral Caverns

The cavern system

Tidal flow over millennia has etched the base reef into a complex network of interconnecting tunnels and cathedral-like chambers. Unlike true caves, these caverns have multiple openings that allow natural light to filter through, creating the sun-dappled effect that makes this site so photogenic.

The passages vary in size from intimate swim-throughs to spacious chambers where multiple divers can gather. The walls are covered in encrusting corals and sponges, while the cavern floors hold scattered rubble and sand that provides habitat for crustaceans and bottom-dwelling fish.

Silverside spectacle

The caverns serve as shelter for enormous schools of silversides, small silver fish that aggregate in dense clouds within the protected passages. When present, these schools create living curtains of fish that swirl and flow around divers, parting and reforming in hypnotic patterns.

The silverside aggregations attract predators including tarpon, jacks, and reef sharks, creating opportunities to witness predator-prey interactions within the confined cavern spaces. The spectacle is most impressive during summer months when silverside numbers peak.

Marine life and topside coral

Above the cavern level, the reef top hosts healthy stands of elkhorn coral alongside brain coral, star coral, and sea fans. This shallow zone is accessible during safety stops and adds variety to the dive profile.

Within and around the caverns, divers regularly encounter eagle rays gliding past the openings, hawksbill turtles resting in the recesses, and grouper that have become accustomed to divers. The resident grouper known as Calypso is particularly friendly, often approaching dive groups.

Architecture of the Caverns

Coral Caverns exists because the Atlantic Ocean never stops working. Tidal currents flowing across the reef off Green Turtle Cay have spent millennia carving passages through the coral substrate, creating a network of interconnecting chambers that resemble a submerged cathedral more than a typical reef formation. Unlike true caves formed by dissolution of rock, these caverns result from the constant grinding of water against coral, with each tide cycle removing microscopic particles that eventually become passages wide enough for divers to swim through.

The cavern system sits at 50 to 60 feet depth, with the reef top above hosting healthy stands of elkhorn coral that provide snorkeling opportunities and extended safety stop environments. Multiple openings throughout the cavern network allow natural light to filter through, creating the sun-dappled effect that photographers prize. Even in the deepest recesses, divers can typically identify exit routes by following light gradients, a safety feature that distinguishes these caverns from true caves requiring specialized training.

The Silverside Phenomenon

From June through September, Coral Caverns transforms into one of the most spectacular dive sites in the Bahamas. Millions of silversides, small baitfish averaging two to three inches in length, aggregate within the protected passages to avoid open-water predators. These dense schools create living walls of silver that fill entire chambers, parting and reforming around divers like mercury flowing around obstacles.

The experience of swimming through a silverside aggregation defies easy description. Fish brush against exposed skin in continuous waves, their collective movement creating sensations that range from ticklish to almost hypnotic. Sound changes underwater when surrounded by millions of tiny bodies, as their movement creates a soft rushing noise that blends with the rhythm of your own breathing. Photographs cannot fully capture the three-dimensional immersion of being inside a swirling silver sphere.

The silversides attract predators that create their own dramatic encounters. Tarpon materialize from the blue water beyond the cavern openings, their silver bodies flashing as they charge into the baitfish schools. Horse-eye jacks hunt in coordinated packs, herding silversides against cavern walls where escape becomes impossible. Observing these predator-prey dynamics in the confined cavern spaces creates wildlife encounters more reminiscent of a nature documentary than typical reef diving.

Resident Characters

Coral Caverns has developed a reputation for friendly marine life that seems genuinely curious about visiting divers. The resident grouper known as Calypso has been greeting dive groups for years, approaching without hesitation and posing for photographs with the patience of a professional model. Brendal's Dive Center, the primary operator at this site, maintains feeding relationships with certain fish that enhance encounter reliability without creating problematic dependency.

Eagle rays glide past the cavern openings with metronomic regularity, their spotted wings spanning four feet or more as they cruise the current lines where plankton concentrates. Hawksbill turtles rest in recessed ledges within the caverns, their amber shells providing color contrast against the grey coral substrate. Green moray eels occupy crevices throughout the system, their heads protruding as they pump water across their gills in the continuous breathing motion that can appear threatening to inexperienced divers but indicates nothing more than normal respiration.

Reef sharks patrol the deeper edges of the cavern system, their presence adding excitement without danger. Caribbean reef sharks in the Abacos have grown accustomed to divers over decades of diving tourism and typically maintain comfortable distances while going about their territorial business.

Photography and Lighting

The combination of natural light effects, wildlife density, and structural drama makes Coral Caverns a premier underwater photography location. Wide-angle lenses capture the scale of cavern chambers with silversides filling the frame and sunbeams streaming through overhead openings. The challenge lies in balancing exposure between bright light zones and darker recesses, a technical problem that rewards experimentation with ambient-light techniques.

Strobe positioning within caverns requires careful attention to avoid backscatter from suspended particles that even apparently clear water contains. Many photographers find success by positioning strobes at arm's length to the sides, angled slightly outward rather than directly at subjects. The abundant natural light during midday dives allows for strobe-free shooting that emphasizes mood over detail, producing images with dramatic silhouettes and ethereal quality.

Video shooters prize Coral Caverns for the constant movement that silversides and their predators provide. The confined spaces create natural boundaries that keep action within frame, while light variations as clouds pass overhead add dynamic range to footage. The site has appeared on Travel Channel and CNN features about Bahamas diving, demonstrating its photogenic potential at the professional level.

Seasonal Timing and Conditions

Peak silverside aggregations occur during summer months, roughly June through September, when water temperatures reach their warmest and baitfish populations concentrate in protected areas. Divers specifically targeting the silverside spectacle should plan visits during this window, understanding that exact timing varies year to year depending on water conditions and the complex factors that drive fish behavior.

Outside silverside season, Coral Caverns remains an excellent dive site with different character. The structural beauty of the cavern system itself provides year-round interest, and resident marine life does not migrate with the baitfish. Eagle ray sightings actually increase during winter months when cooler water seems to concentrate these animals around reliable food sources. Visibility typically improves during the dry season from November through May, when reduced rainfall means less sediment runoff from surrounding islands.

Water temperatures range from approximately 75 degrees Fahrenheit in winter to 84 degrees in summer. Most divers find a 3mm wetsuit sufficient year-round, though some prefer 5mm during the cooler months, particularly for multi-dive days when evaporative cooling between dives compounds the thermal challenge.

Getting there

Coral Caverns is accessed via dive boat from Green Turtle Cay, typically through Brendal's Dive Center or Green Turtle Club Resort. The site is a short boat ride from New Plymouth harbour. Visiting sailors can arrange dive trips through the resort or explore by dinghy with appropriate snorkelling gear for the shallower sections.

Frequently asked questions

When are silversides present at Coral Caverns?

Silverside aggregations are typically largest during summer months, roughly June through September. Outside this period, the caverns remain impressive but may have fewer schooling fish.

Do I need cavern certification to dive Coral Caverns?

No. The site features open caverns with multiple exits and natural light throughout. Standard open water certification is sufficient, though comfort with enclosed spaces is recommended.

How deep is the reef top at Coral Caverns?

The elkhorn coral gardens above the caverns begin at around fifteen to twenty feet, making them accessible for snorkellers and ideal for extended safety stops.

How do the caverns at Coral Caverns compare to true cave diving?

Coral Caverns features open caverns with multiple exits and natural light throughout, making standard Open Water certification sufficient for exploration. True cave diving requires specialized training, equipment, and procedures not needed here. The psychological element of overhead environments exists but is mitigated by visible light and multiple exit options. Divers comfortable with enclosed spaces will find this site accessible, while those with claustrophobic tendencies should discuss concerns with dive operators before committing.

Can I feed the fish at Coral Caverns?

Brendal's Dive Center maintains feeding relationships with certain fish at this site, with guides carrying food for planned interactions. Independent feeding by visiting divers is discouraged as it can disrupt established patterns and potentially create aggressive behavior. The resident grouper Calypso and other regularly encountered animals approach divers without food incentives, having learned that divers present no threat.

What happened to the elkhorn coral reefs above the caverns?

The elkhorn coral stands at Coral Caverns are among the healthier examples remaining in the Caribbean, though even here the species has declined from historic levels. Disease, bleaching events, and storm damage have reduced elkhorn populations throughout the region since the 1980s. The shallow reef top above the caverns still supports sufficient elkhorn growth to provide snorkeling interest and serves as habitat for juvenile fish that eventually populate the deeper cavern environment.