Periophthalmus kalolo (P. koelreuteri africanus)
As a kid, the first time I learned about the existence of mudskippers, or mudhoppers, I was flabbergasted. Here was a fish-out-of-water that actually didn’t mind that at all! To this day I still find the idea absolutely fascinating. Mudskippers are amphibious fish that can survive out of water for considerable lengths of time by holding oxygenated water in their gill chambers and “breathing” through their wet skin and throat. Their pelvic fins are fused into suckers, allowing them to attach themselves to rocks and branches. And if that wasn’t astounding enough, they can use their fins and tails as legs and actually walk, run, hop, skip and jump on dry land!
The African Mudhopper is a small fish, growing to a maximum of about 14cm in length. They are carnivorous, feeding mainly on crustaceans, other invertebrates and smaller fish and spending most of their time looking for food on land rather than in water. When resting they usually do so with their tails in the water and bodies on the shore. Mudskippers live in the intertidal zone of river mouths, lagoons and estuaries, where the influence of the river, sea and tides conspire to create a challenging and constantly changing world of varying salinity and water levels. When their preferred mud flats become inundated by the incoming tide they hide from predatory fish in burrows that they dig themselves or they may use those of other creatures, like crabs, for the purpose. Males are territorial and display their colourful fins prominently to intimidate challengers and attract mates. Females lay their eggs inside the male’s nesting tunnels after mating, and the pair then cares for the eggs until they hatch.
The alternative name of “Common Mudskipper” is actually much more appropriate for this species, as they occur widely along the Indian and Pacific Ocean coastlines of Africa, Asia and Australasia. In our experience one of the very best places in our country to see these unique fish is the boardwalk through the mangrove swamp at Umlalazi Nature Reserve on the Kwazulu-Natal north coast.