Mudskippers

The Common mudskipper and Bluespotted mudskipper ( Boleophthalmus pectinirostris) are two common mudskippers found in Hong Kong. The Common mudskipper is smaller in size with dark stripes on its body - like the one pictured - whilst the Bluespotted mudskipper - wait for it - has distinctive blue spots.

How did they get their name? Well, they live on mudflats where they search for food such as algae, and they “skip”. These strange creatures are actually amphibious fish, which can live in, and out of water, and use their side pectoral to walk, jump and move around, and even to climb trees. These fish are very active out of water, constantly defending territory, or courting, and they live in burrows in intertidal habitats, which are made by the males, who also look after the hundreds of eggs laid by the female.

Perhaps the most interesting thing about mudskippers is their ability to thrive in and out of water. When on land they are still able to breathe using water that is trapped inside their rather large gill chambers - which is why they seem to have puffed up cheeks. They are also able to absorb oxygen from the lining of their mouth, throat and skin (like a frog) allowing them to stay out of water - where they actually spend most of their time. The fish have a sac filled with water beneath their eyes (a dermal cup) and when on land, the fish pull in their eyes to moisten the eyes with the water in the sac, looking as though they are blinking.