Mud Crab Feeding Habits
Live feeds utilized in mud crab larval culture commonly include microalgae, rotifers and Artemia, although Artemia is the only live feed used in some hatcheries. Areas will need to be designed for both rotifer and Artemia production. These should be adequately separated to reduce the potential for cross-contamination of live food and larval rearing areas.
If an algal production laboratory and tanks are required a separate area should be constructed for this purpose within or adjacent to the hatchery. Typically when the hatchery produces its own algae, a quarantined room is used for the laboratory-scale culture production up to 10–20-litre volumes. Facilities are required for sterilizing the water and hygienically transferring algal stocks. Larger algae volumes of 500–5 000 litres, in tanks or large plastic bags, are cultured in a dedicated area indoors or outside.
However, in recent years, commercially grown microalgae, which are then concentrated for sale, can often be more cost-effective for a business than growing its own, when construction, operational and staffing costs are factored in.
There are two main methods for producing rotifers to be used as a feed for larvae:
- Low intensity – rotifer densities range from 100 to 300/ml. Utilizes on-site cultured live algae as feed. A hatchery would require at least several tanks each with volumes of about 2 000–5 000 litres depending on hatchery size. Cultures are managed in batches or semi-continuouly for a short period.
- High intensity – rotifer densities are typically between 500 and 1 500/ml, but can be higher. Utilizes concentrated algae pastes. Tank size is 300–1 000 litres. Requires facility for continuous water flow-through or recirculation through treatment system. Cultures are managed continuously for indefinite periods.
High-density rotifer production systems can dramatically reduce the number of rotifer production tanks required for a hatchery. An example of a high-density rotifer production system, designed to produce rotifers for fish larval production at the Darwin Aquaculture Centre (DAC), Northern Territory, Australia, which has also been adapted to produce rotifers for mud crab production in Micronesia.
An Artemia hatching system sized to meet the demand of the mud crab larval rearing facility at peak demand should be installed in close proximity to the larval rearing area to minimize technicians’ work in transferring of feed to stock. Artemia hatching systems and methods are detailed in numerous publications.
Article Related Questions:
- Can you farm mud crabs?
- What do mud crabs feed on?
- How do you export a mud crab?
- How fast do mud crabs grow?
- Can Muslims eat mud crabs?