The Fish That Can Climb Trees and Breathe Air

When a Fish Walks Out of Water

When you think of a fish, what comes to mind?

Gills, fins, water — and absolutely no business being on land.

But nature, as always, loves exceptions.

Somewhere in the muddy banks of mangrove forests and tropical swamps, lives a creature that completely breaks the rules of what it means to be a fish.

It breathes air.

It walks using its fins.

And some say, it even climbs trees.

Meet the mudskipper — a fish so bizarre, scientists once struggled to believe it was real.

What Exactly Is a Mudskipper?

Mudskippers are a group of amphibious fish from the family Gobiidae, found mostly in the tropical Indo-Pacific region.

Unlike regular fish that suffocate on land, mudskippers have evolved to thrive in both water and air. In fact, they spend more time out of water than in it.

They’re often seen flopping along muddy shorelines, leaping between puddles, or resting on mangrove roots — completely exposed to the open air.

So how do they survive this?

Breathing Without Water

Mudskippers are equipped with multiple breathing strategies:

1. Modified gill chambers: They trap a bubble of water in their gills, allowing gas exchange even on land.

2. Cutaneous respiration: They can absorb oxygen through their moist skin and the lining of their mouth and throat, just like amphibians.

3. Behavioral tricks: They keep their bodies wet by returning to water or burrowing into moist mud tunnels during heat.

In short, they’re part fish, part frog, part alien.

This adaptation allows them to explore environments most fish would never dare — like mudflats exposed at low tide, where food is abundant and competition is low.

Walking (and Climbing) with Fins

Mudskippers move on land by using their pectoral fins like legs.

These fins are muscular and jointed enough to allow crawling, hopping, and even climbing.

Yes, climbing.

Some species — like Periophthalmus barbarus — have been observed climbing mangrove tree roots, especially during feeding or escaping predators.

They use a combination of:

• Fin-powered thrusting

• Suction from their mouths

• Body wiggling for balance

While they’re not exactly swinging from branches, they can scale vertical roots and low trunks — a truly rare ability for a fish.

Eyes That Pop and Roll

One of the mudskipper’s most noticeable features is its bulging eyes, which sit on top of its head like periscopes.

These eyes give it a 360-degree field of view, crucial for spotting predators and prey on land.

Even more bizarre — they can move each eye independently, allowing them to scan in multiple directions at once, like a chameleon.

And when the eyes get dry?

The fish simply pulls them back into the sockets to moisten them.

It’s part fish, part tank, part cartoon.

Life in the Mud

Mudskippers aren’t just land tourists. They’ve adapted their entire lifestyle to the intertidal zone.

They build U-shaped burrows deep into the mud, which:

• Stay cool and moist

• Provide shelter from predators

• Function as breeding chambers

• Hold pockets of air they can use when hiding

Males are especially territorial. During mating season, they put on dramatic displays — leaping into the air, flaring fins, and chasing rivals across the mudflats.

It’s a full-on mud wrestling match.

Why Climb Trees at All?

While climbing isn’t something all mudskippers do regularly, certain species have been spotted scaling mangrove roots for a few reasons:

• To hunt for insects or algae growing on the bark

• To escape tidal floods or aggressive predators

• To find a better view of their territory or potential mates

In this context, climbing is a survival tool — and another reason mudskippers dominate the slippery edge between water and land.

A Window into Evolution

Mudskippers are more than just weird fish.

They’re also seen as living clues to how ancient vertebrates may have first crawled onto land.

Scientists believe the evolutionary leap from water to land happened over 350 million years ago — and mudskippers, with their fin-walking, air-breathing abilities, may mirror what those early pioneers looked like.

In studying mudskippers, we’re looking at a snapshot of evolutionary history, frozen in slime.

Conclusion – Not Your Average Fish

The mudskipper is a biological contradiction:

A fish that breathes air

A swimmer that climbs trees

A sea creature that lives in the mud

It rewrites what we thought was possible in the natural world.

So next time you’re near a muddy coast, look for a creature with googly eyes, flapping fins, and a bold attitude — leaping between land and sea like it owns both.

Because it kind of does.