Giant Beach Worms are long and thin, 1.5 cm wide, they can grow up 300 cm long. They have hundreds of body segments. They have short tentacles near their head.
These beachworms are from the family Onuphidae, also known as polychaete worms.
The three main species of beach worm harvested commercially and recreationally for bait in Australia are:
Australonuphis parateres, Paxton, 1979; Common names are: slimy, redhead, bluey, bungum worm (only in South Australia), can grow up to 300 centimetres in length.
Australonuphis teres , Ehlers, 1868, (are known as: kingworms, greenheads, bonzeheads and bullworms; juveniles are called stumpies, standard beachworms and high-tiders) can grow up to 100 centimetres in length and
Australonuphis mariahirsuta , Paxton, 1979,( has many common names: wiry, white-headed wiry, wireworm, hairy Mary, hairy head, whisker, spider, greasyback and blackhead) can grow up to a moderate size but not liked as a baitworm. If placed in the same container with others, it makes them all wriggle and break to pieces.
Other beachworms are Hirsutonuphis gygis (Paxton, 1979) This is also large but rare, very hard to catch, not well known and has no common name.
Beachworms are widely distributed along the eastern and south-eastern coasts of Australia. They are commonly found from Yeppoon in Queensland to Noarlunga in South Australia (Paxton 1986). Beachworms often have a patchy distribution and prefer open beach sections that have gentle slopes and long swash periods.
They are found in sandy beaches at the low water mark. They are omnivores, scavenging seaweed and animal matter that washes around in the drift zone of beaches.
Living under the sand, the Giant Beach Worms are rarely seen as they only come out of the sand only to feed on dead fish, seaweed, dead octopuses and Pipis. They poke their heads out of the sand and grab the food in their jaws and eat it.
Fish and birds eat Giant Beach Worms.
They live hidden in the sand in burrows or in tubes that they make. They build temporary burrows by secreting mucus onto the sand to create a thin tube to live in.
Pipis and fsh frames are often used by fishers to catch them when their heads emerge from the sand to feed.
When they are about 40 cm long, beachworms reach sexual maturity. They reproduce by external fertilisation, with male and female beachworms releasing gametes into the water column in a synchronous spawning that peaks during the summer months. The fertilised eggs develop within the water column as pelagic larvae, feeding on phytoplankton until they are about 3 cm long, then settle on sandy ocean beaches.
Giant beachworms are collected for bait for use fishers. They are collected by hand, using a bait to lure the worm out of its burrow. Once the worm is caught it is then pulled out of the sand by hand or with pliers. According to the NSW Dept. of Industry and Investment, currently there is no evidence of over harvesting and this is unlikely to change given the labour intensive method of collection.