How Cuttlefish Could Redesign Beach Safety

 A swim that went wrong.
 A lifesaver’s eyes locked on mine.
 And a question I couldn’t shake.

Most safety systems are built for calm moments. But danger rarely shows up when we’re calm. At the beach, water reorganises itself minute by minute, yet the signals we rely on stay exactly the same.

What happens when static signals try to manage moving risk?

From static surf flags to cuttlefish, this is a story about sensing change, signalling state, and what happens when things that don’t move are designed to manage those that do.

Not about sharks.
Not about following rules.

But about what it would feel like if our safety signals could change state, the way cuttlefish do.

Nature owns the patent. We get to copy it.

Biology: Cuttlefish dynamically change colour, contrast and texture to signal internal state in real time, making changes instantly visible to others.
Principle: Signals should reflect changing conditions, not fixed states, so that risk is communicated in real time.
Application: Reimagining safety systems such as beach signals or wearable devices that change state with conditions, enabling people to sense and respond to risk as it emerges.

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Created and hosted by Pia Williams
Clever by Nature. Feral by Design.

Transcript

SPEAKER_00 0:00

Before we start, a quick note. Over the past couple of weeks we've had a tragic spate of shark attacks at our beaches. This episode was recorded before that, but it felt important to acknowledge it. The family is grieving and a lot of people are being extra careful right now, and that matters. This episode isn't about sharks, it's about reading water and beach conditions and the signals we use to stay safe at the beach. Hello and welcome back to all of us. Thanks for sticking with Ferrell for a whole new season. Woohoo! Quick heads up this season. Feral's gonna land in your feed fortnightly. Let's just try that on for size. One of those swims you do without thinking because you've done it a hundred times before. I've got this little ritual actually. The last day of every year and the first day of the next one, I have to have a swim. Hello high tide. Anyway, on that last day of 25, I don't know how many of you went to the beach, but the waves were wild. They were really high tide, really rough, sand was churning everywhere. And true to the year that was, I'm gonna say I went out of 2025 in spectacular humbling fashion. I got dumped, like properly punished. And I'm talking about the waves, by the way, not my romantic life, thank you. And it was actually at the part of the beach locals call Kitty Corner, no less. Humiliating. I stumbled out of the surf, giggling, definitely a tangled mess of hair, and my swimsuit was carrying a crotch full of sand. The walk of shame. Lovely way to end the year. Anyway, an hour later I'm driving home, an emergency vehicle screamed past me. We were talking ambulance, rescue, the works. A boat had overturned on the rocks at the north end of that beach, and one person was dead, and there was a 14-year-old boy missing. By the end of that first week of the year, more than seven people had drowned in just those first few days, and several more were, actually and still are, missing across our beaches. It got me thinking, most people who spend time at the beach carry at least one story they don't talk about much. I don't know about you, but mine was Christmas Eve a couple of years ago. We'd popped down for a cheeky Christmas swim at a beach I know pretty well. Not between the flags, it was one of those unofficial local swim spots. And like a lot of others, we were probably waist deep. Frolicking, loving life, twelve out of ten vibes. And then the water started changing its behaviour. And within what felt like a couple of minutes we were chest deep. Still only about nine meters from shore, but being dragged straight towards the rocks. I could still stand, and I knew the theory, walk parallel to shore and try to stay upright and walking. But right meant straight into the rocks, and left meant fighting this strong pull into what looked like calm water that just screamed rip to me. Neither option felt right. Nothing felt intuitive anymore in that moment. I don't know if any of you have been stuck in this situation. Anyway, my friend that I was with is tiny, so I grabbed hold of her and somehow we waded out and avoided the rocks. We were able to get out of the water. What I remember most isn't actually the water itself and how it behaved. It's the lifesaver. She was standing at the water's edge, red and yellow little cap on, and watching us intently. Her eyes were locked on mine, and we had this whole conversation without words. She was checking, have you got this? And I was saying, I think we're okay, but please don't look away. And of course she didn't, and we were fine. What struck me later was how much of our beach safety depends on noticing, interpreting, and responding to signals correctly, in moments when we're least equipped to do that, when we're under stress and we're starting to panic a little bit, and nothing seems intuitive anymore. That moment taught me something I couldn't unsee. Our safety systems are built for people who aren't panicking, but panic is exactly when we need them the most. Fast forward to just this morning, actually, I'm back at the beach, and I noticed the flags have extra panels on them today. Doubled up fabric. I have no idea what that means. Is that a signal? Is it saying today's rougher than usual? Or is it just because there are more people here we've put up extra flags so you can find us? I genuinely don't know. I asked my parents, and they've been swimming at these beaches for more than fifty years, and they had no idea what double panels mean either. Which is quite interesting. We have these signals, high contrast, easy to spot, and even people who've been looking at them their whole lives don't really know what they're communicating beyond swim here. On that note, fun trivia most Aussies don't know, our flags stole their design from the maritime signal for Man Overboard. Since the 1930s for the win. Red and yellow, both warning colours. So the safest place to swim is between two hazard signals. That's not obvious. That's learned. Picture this: you're somewhere you don't know well, like a new town or a new street. You see two orange witches' hats or traffic cones, about a meter apart on the road, and maybe there's a pothole or something between them. Your body doesn't think safe path, does it? It thinks hazard. Avoid it. Research shows many international visitors, even after reading safety materials at airports and hotels and things, actively avoid swimming between our flags. And this isn't because they're careless, this is because in many cultures, red means danger, stay away. So they read the flags exactly as they've been taught their whole lives, and then swim outside of them. This is true. In recent studies, one of them for Bondi, one in three, that's 30%, however you like your maps, one in three believed swimming between the flags is for confident locals only. More than 60% of South Korean and Japanese students in this study read the red and yellow flags as a danger zone. And if you're sitting there rolling your eyes, going, nah, tourists, half of the Australian university students surveyed assumed surface should also stay between those flags, as it's the only safe place on the beach for anyone. See? You've got the same system, different readings, same risk. People are reading the flags just through different lenses. And that's when it started to land for me. This isn't just a knowledge problem. It's a signalling problem. We're using signals that don't change to manage conditions that never stop changing. Static warnings for moving risk. I started thinking about how nature handles risk in environments that never sit still. And one of my faves popped up. The cuttlefish. If you've never seen one up close, cuttlefish are extraordinary. They're really alien-looking. They've got eight arms, of course, and two longer tentacles. They've got eyes that track you with a kind of unsettling intelligence. But the wildest thing about cuttlefish isn't actually how they look. It's the fact that they don't have a look. When everything's fine, there's no threats, there's no drama, they're subtle, smooth, almost boring. You could swim past one and barely register it. I know I have. But the second something shifts, like a predator nearby, or prey that gets twitchy, or shadows or light changes, their entire body physically transforms. Tiny little pigment sacks in milliseconds. Colours snap into high contrast. Striking patterns appear and start pulsing. Their skin even changes texture. They get like goosebumps. Their fear becomes three-dimensional. And here's the key takeout for me from all of that. The animal becomes the signal. The function is to make your internal state instantly visible. And that forces an immediate response in real time, in constantly changing environments. You don't need to speak the language, you don't need prior training, and you may not have even met before. Your body reads it instantly. Something's different. Pay attention. And that's why it works under stress. That's why it works across species. This is state signaling when the organism's condition is the signal. Our beach flags aren't that. They're location markers. This is what I've started calling a static signal problem. When fixed signals try to manage moving risk. So cuttlefish give us two core design principles here. The first is the signal intensifies as the risk rises. The second is the change itself grabs the attention. So whether that's colour, texture, movement, or form, it's the actual change that's grabbing the attention. Now, if we were doing this with full rigour for a work project, we'd look across multiple organisms. But cuttlefish show the pattern clearly enough for your listening pleasure. Now, come back to the beaches. That New Year's Eve morning, sitting on my towel, drying off, I watched a rip open up maybe twenty meters from where the flags were planted. Everything was shifting. The water was doing what water does, reorganizing itself minute by minute. Same spot, but within twenty minutes, it didn't look the same at all. But the flags, they stayed exactly the same. Polite, static. And I think that's a gap. In water that reorganizes itself minute by minute, we're relying on signals that don't. Inside the conditions they were designed for, the flags work really well. There hasn't been a recorded drowning between the flags in recent years. But they're easier to follow than they are to actually read and understand. They tell you where to swim, but they don't tell you how worried to be. So what would that look like if we applied those cuttlefish design principles here? Gee, I'm glad you asked. Into the void. The flags still get moved each day, the lifesavers still chasing the safest water for people to swim. But what if the flags changed as the water changed? Not moved, changed. Same spot, different intensity, a volume dial. When the ocean's calm, they're quiet. Ordinary, just the location marker that it is. Swim here, come play. But as conditions escalate or change, the signal escalates with them. Extra panels unfurl or colours shift or movement becomes unmistakable. Not just flapping, but something deliberate to stand apart from everything else that's moving on the beach. You wouldn't need to know what it meant. You'd just know this isn't the normal version of the beach anymore. And because that change is shared, being visible to everyone at once, it interrupts something else we're really terrible at. And it's that false confidence cascade. You know, where we assume a spot must be safe because other swimmers are swimming there. Christmas Eve, me two years ago, for instance. Or because it was fine when I went for my last swim 20 minutes ago, it should still be fine. A changing signal gives everyone the same read on the water at the same time. Whether you're in the water looking back, or if you're in the car park, coming back with ice cream melting through your fingers or hamburger juice, or you're up the other end of the beach completely. And once you see this as a signalling problem, the logic doesn't stop at the shoreline. And here's where I had some real fun. Because what about the places without flags? Unpatrolled beaches, the rocky areas, the other end of the beach where locals always swim anyway, harbour beaches, bay beaches, river beaches, all of these unpatrolled ones. So many of our popular beaches around the country aren't patrolled. And I'm talking about popular ones, not the weird and wild ones. We only patrol 5% of our 10,000 beaches. So I started playing with this idea. Call it a cuttle band. Thank you, Mr. Cuttlefish. Think of it as the simplest possible version of gear that divers already use, the wristwatches that can read and do everything and almost swim themselves, but stripped right back. So no screens, no numbers, no data, nothing like that. It's passive in that regard. It's just a band that you wear on your wrist or your ankle. It senses how the water is moving around your body. So imagine you're at one of these many unpatrolled beaches, super popular, lots of people around. You wade in, and the water feels fine until the current shifts, maybe sideways, and your legs are working harder, but you can't quite tell why, and you don't know how bad it is yet. And then you feel it. A firm squeeze around your wrist. A physical tightening, like something has just grabbed your attention. The band just told your body, the state of the water has changed. The same way a cuttlefish skin shifts from smooth to spiked, the goosebumps. Your signal around your wrist changes state. In this way, you, as the swimmer, become part of the signalling system. I'm not pretending this is easy. I am acknowledging that it is fascinating though. Because biomimicry asks us to look at problems differently. Not how do we educate people better about our static signals, but why are we using static signals at all? And not how do we make people pay more attention, but how do we make signals that demand attention when conditions change? Cuttlefish don't post warnings and hope you read them. They become the warning. So next time you're at the beach, sunny's on, towel under your arm, doing that casual little walk like you absolutely meant to come to this exact spot. Just pause for a second. Look at the water, because it's always signaling. Then look at the flags. Same colours, same shapes, same message, no matter what the ocean's doing. And just sit there for a second. What would it feel like if our safety flags and signals could change state instead of politely watching on in silence? What if they could cuttlefish? Somewhere not that far away, a lifesaver today is reading that beach with extraordinary skill. The question is whether our current signals let the rest of us feel what they can see. I'm Pia, and this is Feral by Design. Nature owns the patent. We get to copy it.