Roni Essex
Freediver, Spearo, Creator
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Roni Essex
Freediver, Spearo, Creator
Most people imagine the underwater world as a realm of silence, muffled and serene, where the only sound is the diver’s own breath. But ask any spearfisher who’s missed a fish by milliseconds, and they’ll tell you: the ocean is anything but quiet. It’s a layered acoustic jungle. And while we focus on visibility, hydrodynamics, and camouflage, there’s one element many spearos overlook: sound. Fish hear. They sense. They react. And more often than not, they do so long before you even see them. This isn’t about loud engines or boats overhead. This is about you, your heartbeat, your fin strokes, your carbon blades flexing in the water, even the slight clink of gear against your weight belt. Every sound you make creates a ripple. And if you want to be a better hunter, you need to understand what those ripples do. This is the soundtrack of the hunt.
Fish don’t have ears like humans, but they do hear. In fact, many species detect low-frequency sound better than we can. Their hearing is split across two systems. First, their inner ear. Vibrations in water pass through a fish’s body and cause tiny ear stones called otoliths to move. The fish interprets this as sound. Second, the lateral line. This is a sensory organ that runs along both sides of a fish’s body. It detects minute water movements and vibrations, essentially giving them a 3D awareness of motion in the water around them. Imagine being able to sense not just the direction of a sound, but its pressure, speed, and volume, through your entire body. That’s what fish experience. It’s no surprise they’re often gone before your finger even finds the trigger.
Let’s break down your typical dive and examine the acoustics from the fish’s perspective. Finning might be the noisiest thing you do underwater. Long, forceful strokes, especially with stiffer blades, generate a surprising amount of water movement and vibration. Carbon fins can create a sharp whomp sound as they flex and return. If you’re wearing footpockets that don’t fit snugly, you might also create subtle slapping or clicking sounds. Fish detect the hydrodynamic pressure waves created by your kicks well before they see you. For reef fish especially, a strong fin stroke signals a predator approaching fast. Use shorter, smoother, frog-kick-like movements when approaching your target. Soft blade fins, like Alchemy S30 in medium-soft, are often quieter and more forgiving for stealthy approaches.
A dangling buckle, a loose weight, your gun shaft clicking into place, any of these can become sonic warning flares underwater. While these sounds might seem minimal to us, in a fluid medium like water, they travel far. Water carries sound almost five times faster than air, and with much less loss of energy. That tiny clink from your loading tab might echo across several meters, especially in calm conditions. Secure every piece of gear tightly. Use rubber bands, Velcro, or tape where needed. Practice loading your speargun silently, using your body and gear as buffers.
As you equalize and descend, you might unconsciously exhale small bubbles through your mask or mouth. In deep drops, this isn’t as much of a problem. But in shallower hunts or reef spearfishing, these tiny bursts of sound give away your presence. Even the popping of ears and crackling joints, yes, some divers’ knees or shoulders crack underwater, can become part of this subtle acoustic signature. Equalize early and gently. Make your descent as slow and quiet as your buoyancy and stalking distance allow.
Yes, fish may detect your heartbeat, indirectly. On deep drops, bradycardia, the slowing of heart rate, reduces the pressure waves your body sends through the water. But when you’re anxious, excited, or rushing a shot, your heart rate rises, and your body subtly transmits that tension. While not an audible beat, this biological tension can be felt by fish via water movement and electromagnetic cues. Master your relaxation. The calmer you are, the less energy, and acoustic pollution you generate.
Different species respond to different frequencies. Groupers may be more tolerant of certain noises, while snappers and surgeonfish can be hypersensitive. Pelagics like wahoo or tuna are notoriously skittish and will bolt at the first unnatural sound or pressure wave. Moreover, many fish have adapted to hear specific environmental sounds: reef clicks and snaps from crustaceans and corals, wave surges crashing over shallow rocks, predator movement like dolphin clicks or shark approaches. You, the spearfisher, are an anomaly in that soundscape. You don’t belong. And if you don’t mimic the natural rhythm, you risk being identified and avoided before you even spot your prey.
To become a better hunter, start thinking like a submarine. The best subs are designed not for speed, but for silence. Everything is streamlined, quiet, and intentional. You can apply the same principles. A smooth suit, minimal drag, and streamlined gear layout reduce your acoustic signature. Tidy up your loadout. Nothing should dangle. Nothing should scrape. Move like kelp in current. Every motion should be purposeful and slow. Even the act of turning your head or lifting your gun should be slow enough not to create turbulence. Proper weighting isn’t just about trim, it’s about control. A diver who’s properly weighted doesn’t thrash to stay submerged. They glide. That silence is golden. Fish often pause to assess movement. Mimic this. Glide in, stop. Let them settle. Move again. You’ll blend in better with the rhythms of the reef or open water.
Sometimes, conditions work in your favor. Surf zones with crashing waves mask your movement and sound. Use the chaos. Current, the rushing sound of water, helps hide you acoustically. Rainfall, a surface patter above, can create excellent camouflage, both visual and auditory. Learn to read the sonic conditions of your environment. Some days are acoustically loud, and some are sonically clear. Adjust your tactics accordingly.
To become truly silent, you must learn to hear what fish hear. Practice these: dive with no gun. Just observe. Listen to your own noise signature. Film yourself. Use a GoPro or underwater mic to record your dive. You’ll be shocked how noisy you are. Dive with a buddy silently. Try to approach the same fish from different angles. Which one bolts first? In time, you’ll begin to develop not just better stalking skills, but a more intimate connection with the soundscape of the sea.