Snakes and Sea Birds

Another sea day brought more opportunities to scan the horizon for seabirds, dive into a good book, and attend fascinating lectures. It was also a time to reflect on this fantastic journey so far—and to realize that soon, I’ll be packing for our post-cruise safari at Phinda Mountain Lodge.

Don’t Bite Me

“Snakes are first cowards, then bluffers, and last of all warriors.” — Clifford H. Pope, American herpetologist

Envenomate: That’s my new word for the day. You can be bitten by a snake, but even a venomous snake doesn’t always inject venom. If it does, you’ve been envenomated.

On average, across species and geographies, 25% to 50% of venomous snake bites are dry—no venom is delivered. As both Clifford Pope and our onboard naturalist Greg explained, venom is a last resort. You’d have to seriously upset the snake—though stepping on one in bare feet, unfortunately, qualifies.

Greg showed us a partially dissected snake, pointing out the fangs, venom duct, venom gland, and the muscles used to squeeze the gland. Producing venom is biologically expensive, so snakes prefer to avoid conflict unless they’re hunting. Before striking, they’ll often hiss, rattle, spread a hood, or bluff in other ways to avoid wasting venom on a threat they can’t eat. If a bite happens and you’re lucky, you’ll get a dry one.

Greg’s talk went well beyond snakes. He highlighted other venomous animals—corals, frogs, male platypuses, lemurs, spiders, and more. I was especially struck by the global burden of snakebites. In countries like Australia—home to many venomous species—snakebite mortality was 10% to 30% before antivenom was developed. Today, the death rate there is around 0.01%. Unfortunately, many developing countries lack access to antivenom, or to the cold storage needed to preserve it.

In some regions, farmers walk barefoot through fields where venomous snakes are common. Ironically, snakes benefit agriculture by keeping rodent populations in check. Many farmers accept the risk. You might think the solution is simple—just wear boots—but financial and cultural barriers often get in the way.

In 2017, the World Health Organization reinstated snakebite envenoming as a Neglected Tropical Disease. Since then, it has launched initiatives to improve education, antivenom production, and distribution infrastructure, including refrigeration. Still, much remains to be done.

Do You Know the Way to Tristan da Cunha?

The 10 million seabirds that descend on the Tristan da Cunha island group each year are now far out to sea. So are the albatrosses of the Falklands and South Georgia, and millions of penguins. Even non-seabirds migrate thousands of kilometers and somehow make it back to the exact same nesting sites. How do they do it?

Naturalist Martin gave a compelling talk on the theories behind avian navigation.

For decades, magnetic navigation was a leading idea. Researchers once thought birds might sense magnetite—a magnetic mineral—in their bodies. More recent research, however, has shifted toward cryptochromes, light-sensitive proteins in their eyes.

Today, most experts agree that birds rely on multi-modal navigation—a combination of cues. Magnetic and celestial guidance helps them cross oceans. Once closer to home, they may rely on smells, landmarks, or even sounds. One candidate is infrasound—low-frequency sound waves below 20 Hz. Humans can’t hear them, but we sometimes feel them as a chest rumble or pressure in the ears. Birds may be far more sensitive to these vibrations, detecting storms, surf, or geographic features from afar.

The cryptochrome theory is especially intriguing. First suggested in the 1990s and gaining traction in the early 2000s, it proposes that birds sense magnetic fields through quantum processes. Cryptochromes in the retina react to blue-green light and may form radical pairs—entangled electrons whose behavior is influenced by Earth’s magnetic field. Incredibly, this would mean birds are using quantum chemistry to “see” magnetic orientation.

Martin emphasized that there’s still much to learn. As Ed Yong explores in An Immense World, scientists tend to approach animal senses from a human-centric worldview—or umwelt. But by broadening our perspective to include sensory systems entirely foreign to us, we may come closer to understanding the true nature of bird navigation.

Concluding Thoughts

Every day at sea reveals new marvels—birds that navigate by light and magnetism, snakes that strike only as a last resort, and the delicate balance that connects all living things. These discoveries are not just curiosities; they are reminders of how much we have yet to learn, and how vital it is to protect the creatures who share this planet with us. Whether through supporting conservation efforts, advocating for access to antivenom in underserved regions, or simply choosing to see the natural world with fresh eyes, each of us can play a role. Curiosity is the first step toward compassion—and compassion, the first step toward change.