The mudskipper only has to bend the back half of its body, and then it can move forward one jump. This light, quick movement is not special among fish. But these guys can "crawl."
The front fins have strong muscle and skeleton. There are also joints. It looks like it is walking through the mud on two canes. Some types of mudskipper also have an extra set of abdominal fins. Located below the stomach, they are long and oval, suckers like on an octopus. Therefore in some swamps one can realize the old saying "looking for fish on a tree." They can be found on the roots of mangrove trees.
These two sets of fins are tools for coming ashore. But how do they breathe?
After mudskippers leave the water, they will take a mouthful of water, and breathe the oxygen dissolved in the water. Its moist skin has concentrated cells which can directly absorb oxygen from the air. It can remain on the mud for about 40 minutes without having its oxygen cut off.
But there is no way for it to circulate the water in its gills and replenish the oxygen. Its skin will also dry after being exposed to the air, and cannot undertake absorption. Therefore the mudskipper will often go back in the water to wet down or take a breath of fresh water, and we often see it rolling in the mud to soak its skin.
But why would these guys ever want to be on land in the first place?
According to the author of the well known books Life on Earth, David Atten-borough, the reason is--naturally--for the mudskipper to fill its stomach.
The mudskipper lives in coastal swamps in Burma, Malaysia, mainland China, Japan, and Korea, and its traces can also often be found in the muddy beaches of western Taiwan. The zoologist Johnson T. F. Chen has written that besides the large mud skipper, there are also what the Chinese call the "blue mudskipper" (scartelaos viridis) (whose upper body is deep blue, with black spots on the head and fins), and the small sized "jumping mudskipper."
The most commonly known mudskipper belongs to the Gobiidae variety, and is called the "star point mudskipper" in Chinese. This is because its color is aqua, with light colored spots like stars. Its dorsal and tail fins are embellished with fine blue dots; its color makes it easily distinguishable from other mudskippers. It can be up to 20 cm. long, weigh 30 to 40 grams, and live up to seven years.
According to a Japanese study, the mudskipper lives in the water when immature. In order to adapt to its amphibious life, diatomaceae, a plant, will become its main food. But English scholars believe that each swamp ordinarily has three different kinds of mudskipper. Most of the smallest stay in the water, only coming out at low tide. They roll in the mud where they congregate and mate, searching for bugs and tiny crustaceans.
As one goes toward the middle tide area, that's the universe of a larger mudskipper. They are vegetarians, eating diatomaceae and single-celled plants. They travel alone, and are home-oriented. One will dig a hole, searching through the mud all about it. They build little dikes above the hole, often several meters in length, which not only cordon off the neighbors, but also prevent the water from rapidly receding and drying up. Each is master of its home, and they don't invade each other's space.
In the muddy areas closest to land is the third type. They eat little crabs, are experts at digging, and don't care about property rights.
The mudskipper is adapted to a life half in and half out of the water. But while it is "King of the Fish" on land, the shape of its fins makes it a bit weak in the swimming department. They have to use the currents to get back and forth between the sea and the mud.
Besides eating, their other main occupation--finding a mate--also takes place on land. Like most fish, the mudskipper can bend its body and move its fins to catch the attention of the opposite sex. Because its abdominal fins are for climbing, it relies on its two different kinds of dorsal fins and its round tail fin to strut its stuff.
Ordinarily the dorsal fins lay flat. But they come up when the male fish is seeking a partner, and show their colored spots. Because mud is relatively flat, often only the next door neighbors can appreciate the show. To reach the widest audience, the mudskipper will move its tail and jump into the air, with its dorsal fins stuck straight up. It is estimated that one can jump from 50 to 80 times in one hour.
According to a survey of the Taiwan Fisheries Research Institute (TFRI), people began raising mudskippers from 1969 to serve as seafood. But so far there's been little success at mass breeding, natural production is low, and they are hard to "reel in" from their hovels, so that the price is expensive. In recent years, with growing prosperity, consumption of seafood has increased, raising interest in the breeding industry. Large groups of new born mudskippers are caught and then raised.
Since the mudskipper is a fish, and thus an important source of protein, one can only hope that the TFRI quickly figures out a way to raise them en masse. Otherwise, before there's enough time to understand this little life which struggles to keep going on the land, they may all end up as dinner. Then our name would be mud.
[Picture Caption]
Michael Jordan, watch out!
Two males match up, "demonstrating their love" for a female--any idea who's going to come out on top?
Blue star-sprinkled dorsal fins are the way the mudskipper attracts the attention of the opposite sex.
The abdominal fins between the head and body have already become "muscularized," allowing the mudskipper to crawl.
Friend or foe? Crabs and mudskippers are among the few creatures who can live in the muddy coastal swamps.
Two males match up, "demonstrating their love" for a female--any idea who's going to come out on top?
Blue star-sprinkled dorsal fins are the way the mudskipper attracts the attention of the opposite sex.
The abdominal fins between the head and body have already become "muscularized," allowing the mudskipper to crawl.
Friend or foe? Crabs and mudskippers are among the few creatures who can live in the muddy coastal swamps.