Fish

If you're releasing a robot into the aquatic environment with no intention of retrieving it, that bot had better be biodegradable. Swiss scientists have gone a step better, with a li'l robot that can be consumed by fish when its job is done.

A new type of storm-resistant fish farm could make aquaculture operations more eco-friendly. The submersible structure is designed to stay in the deep waters of the open ocean, where it should have less environmental impact than shore-adjacent pens.

Scientists have devised a method of using fish scales to convey encrypted messages. Not only would the technology divert seafood industry waste from landfills, it should also be less costly than existing options such as special inks.

Mangroves may not be the first thing that comes to mind when you think of a forest, but they're both incredible, unique ecosystems and serve as a structural and water-cleaning coastguard. These photos capture the wondrous, otherworldly ecosystems.

Regular water-changes are essential to the wellbeing of aquarium fish, but the task sometimes gets missed, plus it can be hard to determine how much water should be replaced, and how often. That's where the automated StayrAI Rein system comes in.

When designing fish-like underwater robots, you want a means of propulsion which is both energy-efficient and reasonably speedy. A new tail-flapping system may fit the bill, paving the way for wider usage of such bots.

When you're looking at a tank full of fish at a public aquarium, it can be difficult to figure out which ones are which species. The AI Aquarium is designed to help, by overlaying information that lines up with the individual fish in question.

Imagine if there were a robotic fish that filtered microplastic particles out of the water as it swam. Well, now there is one, and it's the physical version of the winning concept in the first-ever Natural Robotics Contest.

While the farming of salmon does help take pressure off wild stocks, the feed used to raise the fish still isn't entirely sustainably sourced. That may change, however, thanks to nutrient-rich worms that eat readily available seaweed.

Researchers at Harvard and Emory have created a biohybrid fish out of human heart cells that swims autonomously for months at a time as the cells beat. The project is a sidestep on the way to eventually growing new functional hearts for transplant.

Given that they're such good swimmers, the structure of fish is increasingly being copied in the design of underwater robots. Scientists have now discovered that by adjusting the stiffness of their tails, those bots can swim much more efficiently.

When spawning fish travel through the canals of Utrecht, they're often blocked by the city's closed Weerdsluis lock. Regular citizens are now helping the fish to get through, though, using an online "fish doorbell."