Large Mudskipper

1 Large Mudskipper Introduction

The Large Mudskipper is a warm-water intertidal fish that likes to jump, crawling and hopping on mud with its pelvic fins to feed, found along China’s coast. It is a small fish, burrowing and solitary; not hard to keep in captivity and also edible.

Chinese name: Large Mudskipper

Binomial: Boleophthalmus pectinirosris (Linnaeus)

Aliases: Jumping Fish, Mud Monkey

Kingdom: Animalia

Phylum: Chordata (Osteichthyes)

Class: Osteichthyes

Order: Perciformes (Gobioidei)

Suborder: Gobioidei (Periophthalmidae)

Family: Periophthalmidae (genus Boleophthalmus)

2 Physical Characteristics

It is a small warm-temperate coastal fish that uses pelvic fins to crawl and hop on beaches or mud, but at any sound it startles back into water or its burrow. Solitary, it breathes through skin and tail, so it can stay on land for long.

The body is elongate and laterally compressed, head large and nearly cylindrical. Usually 10-20 cm long, 20-50 g. Small eyes set high and close, protruding above the head; lower eyelid well developed. Mouth large, slightly oblique, jaws equal; one row of teeth each, upper conical with 3 dog-like front teeth each side; lower teeth slant outward, lying flat. Small cycloid scales, no lateral line. Pectoral base broad with strong muscular stalk; pelvic fins fused into a sucker. Body dark brown, blue spots on dorsal and caudal fins. Back black-brown, belly gray. Six black bars on the back, irregular green-brown spots all over. Two dorsal fins; the first very small with 5 spines, the ends filamentous, the 3rd longest; the second dorsal and anal are long and about equal. Caudal fin wedge-shaped and broad; the second dorsal has 3 gray-white horizontal lines; the pectoral has yellow-green worm-pattern markings, very colorful.

3 Aquarium Conditions

In captivity it is usually kept in ponds. Because it likes to jump, the pond must be large enough for activity. As it is solitary, control stocking density, best about 6 fish per square meter.

The pond is rectangular, 1 hectare, with 50 cm dikes, flat bottom for draining and sun-drying to grow benthic diatoms; soft clay bottom, no perimeter or central ditch, to improve diatom culture and harvest. Convenient access, no pollution, some freshwater source. One drain and one inlet gate; a fence net around the pond prevents escape and predators; a 100-mesh nylon net about 2 m above the bottom guards against birds.

Before stocking, sun-dry the bed, apply base fertilizer, remove predators and trash fish, then fill water to grow benthic diatoms. In May 2004, the pond was disinfected with quicklime at 400 ppm and bleach at 50 ppm (32% available chlorine) to remove pests and pathogens.

4 Feeding Guidelines

It is omnivorous, feeding mainly on benthic diatoms, occasionally eating organic matter in mud, copepods, and roundworms; it usually feeds at low tide. Respect this habit in captivity for healthy fish.

Broodstock can be wild or farmed; breeding season May-September, peak May-June. Choose females about 25 g (older fish larger with more eggs). Good females have a swollen belly and a large round cloacal papilla; males about 20 g with a pointed long papilla. Ready broodstock can be induced to spawn or placed in a spawning pool to spawn naturally (in spawning tubes). Stage 3-4 fish are held in a temporary pool fed with natural beach diatoms; water 20-30 cm deep, change 50% daily, with a feeding table.