Detailed Explanation of Key Points in Australian Lobster Farming Techniques

As farming techniques gradually mature, farming the precious Australian lobster is no longer an impossible task. In fact, many regions of China are well suited to farming Australian lobsters, because the climate in those regions is very similar to Australia's climate, belonging to a subtropical climate, with a few regions belonging to a tropical climate.

Australian Lobster Farming Techniques

1. Suitable growth rate. The natural distribution of the Australian lobster is in subtropical and tropical regions. A good growth rate can be achieved between 18°C and 32°C.

2. Water quality requirements.

(1) Water source: mainly unpolluted surface water from large bodies of water such as rivers, lakes and reservoirs. Groundwater can also be used, and it has the following advantages: a fixed, independent water source; no wild miscellaneous fish carrying pathogens; no pollution; and a relatively stable temperature year-round.

(2) The pH value of the water. During farming, the lowest value recorded was 6.10 and the highest was 9.33, and the lobsters survived at both, but 6.5—9.0 is good, preferably neutral to slightly alkaline.

(3) Dissolved oxygen in the water. Although the Australian lobster tolerates low oxygen and can survive for a short time at dissolved oxygen below 1 mg/L, prolonged exposure to a low dissolved oxygen state will affect its growth and survival rate. Therefore, ponds must be equipped with aerators or other oxygenation equipment when necessary, so as to keep dissolved oxygen above 4 mg/L, and contamination by heavy metals, insecticides, herbicides, oil, chlorine, methane, hydrogen sulfide, high iron content and the like should be avoided.

(4) Using micro-flow water or regularly adding new water for farming can promote lobster growth.

3. Pond conditions.

(1) The pond should be rectangular; the area is not limited, but 2—5 mu is good, the water depth should be 0.9—1.5 m, and the long axis of the pond should run in the same direction as the summer wind.

(2) The pond bottom should be hard soil with no silt, and the pond walls must have a slope, with a slope greater than 3:1.

(3) The pond must have a good drainage and irrigation system, with water entering at the upper part of one end and draining from the bottom of the other end; both the inlet and outlet must be fitted with mesh covers to prevent predators and escape.

(4) The pond bottom should have a submerged plant area covering about 1/5 of the bottom area, along with sufficient artificial shelters, such as waste tires, mesh sheets, PVC pipes, waste ceramic jars, bamboo rafts, etc. (5) Ponds with the conditions for it can be equipped with aerators.

4. Stocking techniques and daily management.

(1) Density: stock 600 juvenile lobsters of 2—3 cm per mu, and 100 silver carp, 50 bighead carp and 50 grass carp may be appropriately polycultured.

(2) Farm with micro-flow water or add new water 2—3 times per week.

(3) Feed using the fixed-point, fixed-time, fixed-quality and fixed-quantity method, and the types of feed should be as varied as possible: aquatic plants such as water hyacinth, water lettuce and floating celery, cow dung, pig manure and artificial pellet feed. Animal bait such as river snails, earthworms and freshwater mussels may also be appropriately fed. Feed fermented cow dung once a week, 100 kg per mu, placed in the four corners of the pond and fully submerged in the water; feed pellet feed once a day, and at 6 p.m. feeding an amount equal to 20% of the lobsters' body weight is sufficient.

(4) During the high-temperature period in summer, pay attention to increasing the flow rate or the amount of water added, and the number of times water is added; at night, aerators can be turned on to increase oxygen.

Disease Prevention and Control of the Australian Lobster

During the broodstock rearing stage, it is necessary to guard against attacks by water rats, water snakes and frogs, and against attachment by ciliates such as Epistylis, Zoothamnium and Vorticella. During the seedling stage, it is also necessary to guard against harm from aquatic insects and their larvae. Therefore, attention must be paid to disinfecting and clearing the pond before rearing, taking certain preventive measures and strengthening feeding management. Redclaw crayfish is highly susceptible to the diseases that crayfish commonly contract, and is also prone to a shrimp disease caused by fungi called "crayfish plague"; as long as the water temperature when stocking and harvesting the shrimp seedlings is kept above 21°C, the occurrence of "crayfish plague" can be avoided. In addition, during farming, the following can be used alternately once every 10 d: quicklime 20 mg/L; copper sulfate plus ferrous sulfate 0.7 mg/L; furazolidone 1-2 mg/L; rhubarb 4-5 mg/L, splashed over the whole pond to prevent disease.

How to Kill and Prepare an Australian Lobster

1. First press down on the lobster's head with a towel, then use chopsticks to pierce the urinary tract in front of the tail to release the urine; if the urine is not released while it is alive, it will have a slightly gamey smell.

2. Use the handle of a knife to strike the lobster's head until it is stunned.

3. Put on gloves or use two towels to protect both hands respectively, then hold the lobster's head with the left hand and the lobster's tail with the right hand, lift the lobster up, and with both hands twist and pull forcefully in opposite directions at the same time; the lobster's head and tail will then separate. (Remember, it is best not to use a knife for this step of separating the lobster's head and tail.)

The Difference Between Australian Lobster and Ordinary Lobster

The lobsters we can normally eat all belong to "Animalia > Arthropoda > Malacostraca > Decapoda", and the main differences lie in the further classification below that. What everyone generally sees as the Australian lobster and the California lobster belong to "Achelata > Palinuridae", so in the strict definition, they are the true lobsters. The Maine lobster and freshwater crayfish belong to "Astacidea > Nephropidae / Astacidae", and their scientific names should be sea crayfish / crayfish. Because sea crayfish are similar in body size to lobsters and both are edible, they are often thought by people to be a type of lobster. In scientific classification, however:

Lobsters have long, thick, spiny antennae, while sea crayfish have thinner and shorter antennae. Sea crayfish have a pair of large chelae (claws), while lobsters have no chelae. The crayfish is actually a small close relative of the sea crayfish that lives in freshwater, and is in fact somewhat distant from the true lobster.

So it turns out that the Australian lobster is the true lobster in the strict sense, while the freshwater shrimp we most often eat is the sea crayfish. It seems that people really are not very clear about the difference between the two. The editor also only learned today that this is a big misconception; fortunately everyone knows now, and from now on they can tell them apart properly.