CATDOLL : CATDOLL: How to keep sea urchins alive

1. How to keep sea urchins alive

The fully artificial breeding of sea urchins has strong controllability of breeding conditions, can be managed by artificial feeding, and has low breeding facility costs. In addition, sea urchins grow fast, have a high survival rate, and reach a short commodity period. The harvest period of commodity sea urchins and their market release can also be artificially controlled, which can further improve the commodity value and economic benefits. At present, sea urchin breeding has entered large-scale production in Japan, France, the United States and other countries, and has achieved good results. Since the introduction of the Yezo horse dung sea urchin, my country has also started a certain scale of offshore raft breeding and onshore factory breeding production experiments. Because the sea urchin has the advantages of fast growth, delicious meat, high meat yield, low disease resistance, and low cost, and its short spines are convenient for cage or indoor breeding, it has made breakthrough progress in a relatively short period of time. In recent years, breeding has developed rapidly in northern my country, promoting the development of my country's sea urchin breeding industry. However, there has been little progress in the research on artificial breeding of some original economic species in my country, such as the light echinoceros ball sea urchin, purple sea urchin, and horse dung sea urchin.

At present, the artificial breeding methods of sea urchins at home and abroad are still mainly offshore raft breeding and land-based factory breeding.

1. Marine raft aquaculture

1. Sea area selection

The aquaculture sea area should be selected in the sea area with clear water, high salinity, no industrial pollution, small freshwater runoff, less floating mud, more than 10 meters deep, and no frozen water layer in winter. At the same time, the sea area where seaweed grows naturally and is easy to set up floating rafts should be selected.

2. Breeding equipment and bait

Raft culture of sea urchins has the advantages of being able to use the same culture equipment as other types of culture equipment, having low culture costs and high input-output ratios. Therefore, it is easier to be accepted by production units in my country and is easy to promote. At present, this culture method is widely used in Japan and my country. There are many types of culture equipment available for raft culture. In Japan, there are also rectangular plastic boxes for culture, and large net cages or net cages for culture. With a large net cage with a specification of 2 meters × 1.3 meters × 1.3 meters, each box can raise about 20,000 1 cm young sea urchins. As the young sea urchins grow up, the culture density of sea urchins should be gradually reduced until it is close to the commodity specifications. At this time, each net cage can be reduced to about 2,000. The feeding bait is mainly seaweed such as kelp. The feeding bait is also mainly seaweed when it is cultivated in plastic boxes (specifications 56 cm × 36 cm × 18 cm, two buckled together) and plastic cylinders (specifications 30 cm × 70 cm). There are two types of cages to choose from: abalone cages, 60 cm in diameter, with 12 layers; scallop cages, 33 cm in diameter, with 12 to 15 layers. Japan also has a cage (80 cm x 90 cm x 30 cm), which is cut into 6 sections, and each cage can hold 5,000 5 mm juvenile sea urchins. When the shell diameter grows to more than 10 mm, the number of cages must be reduced to 2,000 per cage. The mesh of the cage for 5 mm to 10 mm individuals is 3 mm, and when the individual reaches 10 mm, the mesh needs to be increased to 6 mm.

Since the introduction of the sea urchin in Yezo, scholars such as Wang Zichen and some breeding production units have conducted relevant research on the breeding methods of the sea urchin, as well as the breeding equipment, breeding density, bait and other technologies. After the comparative test of marine breeding with different equipment, it is believed that the abalone breeding cages, scallop breeding cages, plastic cylinders and plastic boxes currently used for shellfish breeding can be used for marine breeding of sea urchins. Among them, the plastic breeding cylinder has poor water permeability, and silt deposition is prone to occur in some sea areas, resulting in the death of sea urchins, and the breeding effect is slightly poor; the scallop breeding cage has good water permeability, and existing equipment can be used, and the cost is low, but the area available for sea urchins to attach is small, and the feeding operation is inconvenient. If the feeding port is not sutured tightly, the sea urchin is likely to escape; the plastic basket has a large attachment area, is easy to feed and manage, has a long service life, and is moderately expensive. It is a relatively ideal sea urchin breeding equipment; the abalone breeding cage has good water permeability, a large breeding capacity, and is easy to operate and manage, but the cost is high, and units with conditions can also use it.

Sea urchins are mainly fed with seaweed such as kelp. It is also reported that some units in Hokkaido, Japan use sardine segments instead of seaweed to feed sea urchins, and the breeding effect is significantly better than kelp. The growth rate of sea urchins is 1.5 to 2 times faster than when they are fed with kelp. In France, sea urchins are fed with long kelp and palm kelp. It is reported that it takes about 3 to 7 tons of kelp to grow 1 ton of sea urchins. The feed efficiency is quite high, but the breeding equipment and breeding methods are unknown. Different sizes of sea urchins have different requirements for bait. For example, the 0.3-0.5 cm juvenile galls of the Yezo sea urchin mainly feed on benthic diatoms, cysts and Ulva, the 0.5-1 cm juvenile galls mainly feed on benthic diatoms and kelp, etc. The sea urchins over 1 cm mainly feed on large seaweeds such as kelp and wakame, etc. The feeding selectivity for common large seaweeds is: kelp, wakame, cysts, sargassum, Ulva, spiny pine algae. In addition, when hungry, the Yezo sea urchin also feeds on mussels, bryozoans, stalked sea squirts and other baits. Therefore, this feature can be used to carry out mixed culture of the Yezo sea urchin and abalone to achieve the purpose of dredging and removing bryozoans and other harmful organisms attached to the surface of the abalone. Feeding should be flexible according to the size of the seedlings, growth rate and water temperature. Generally, feed once every 2 days, once every 5 to 7 days during the growth period, and once every 10 to 15 days in hot or cold seasons. Feed in moderation each time to avoid clogging the net and affecting the water exchange in the box.

2. Is there anything I need to pay attention to when transferring sea urchins to water and raising them?

There is nothing to say. They are algae eaters. They mainly feed on calcium algae and also eat a small amount of brown algae. However, they will chew on stones and consume live rocks.

3. How to plant cactus?

Cactus needs a breathable soil without water accumulation. I always use a mixture of soil, coarse sand, and burnt coal ash. Also, planting with seeds is not as good as planting with bulbs [because seeds grow too slowly and the survival rate is not high]. I recommend a variety [Gaosha]. Do you like it? This is Gaosha.

4. How does a cactus grow? How many varieties does it have?

Cactus, commonly known as grass ball, also known as Changsheng ball, is a perennial fleshy herbaceous plant of the Cactaceae family. The stem is spherical or oval, up to 25 cm high, green, with several longitudinal ridges on the sphere, densely covered with yellow-green thorns of varying lengths, radiating. The flowers grow in the longitudinal ridge thorns, silvery white or pink, trumpet-shaped, up to 20 cm long, with scales outside the trumpet and long hairs inside the scales. Cactus usually blooms in the early morning or evening, lasting from a few hours to a day. The sphere often has many small balls on the side, with beautiful and elegant shapes. According to its appearance, cacti can be divided into velvet, wart, treasure, hair column, strong thorn, sea urchin, top flower, etc. The prickles of cactus can also be divided into long, short, sparse, and dense; the color hairs are red, yellow, golden yellow, etc. The planting method is: View article Cactus planting method March 20, 2008 22:10 Cactus is a common type of home flowers. As long as it is properly maintained, it will not only grow fast, but also have a bright ball and luxuriant flowers. 1. Temperature Cactus likes high temperature and dry environment. In winter, the room temperature should be kept above 20℃ during the day and not less than 10℃ at night. Too low temperature can easily cause root rot. 2. Light Cactus requires sufficient sunlight, but it cannot be exposed to strong sunlight in summer and needs proper shade. Indoor cultivation can be illuminated with light to make it grow healthily. 3. Pot soil The soil for potted cactus requires good drainage, air permeability, and lime-containing sand (or sandy loam). It can be made by mixing 2 parts of loam and leaf humus, 3 parts of coarse sand, and 1 part of limestone gravel or old lime wall chips discarded when old buildings are demolished. It can also be made by mixing 2 parts of loam and coarse sand, 1 part of broken bricks, leaf humus and old lime wall chips. When planting, a small amount of broken bricks and tiles should be placed at the bottom of the pot to ensure smooth drainage. 4. Planting: It is best to plant in the pot in early spring. The flowerpot should not be too large, so that it can accommodate the ball and have a slight gap. If the flowerpot is too large, it cannot absorb enough water after being poured, and the air in the pot is blocked, which can easily cause the root system to rot. A few taproot species and bird feather jade, giant elephant balls, etc. require deeper tube pots. Silver hair balls, descendants balls and other shallow root species can use shallower ordinary flowerpots. 5. Repotting method: When repotting, part of the old roots should be cut off. After drying for 4-5 days, it can be potted and planted. It should not be planted too deep, and the root neck of the ball should be level with the soil surface. To avoid root rot, do not water the newly planted cactus. Just spray 2-3 times a day. After half a month, you can water it in small amounts. After a month, new roots grow before gradually increasing watering. 6. Watering: Summer is the growing season for cacti, with high temperatures and high water requirements. It is necessary to water the plant fully, preferably in the morning and evening when the temperature is low. Watering can easily cause burns to the plant during the hot rainy season. Watering should be appropriately controlled during the high temperature rainy season. For those cacti with sunken tops, be careful not to pour water into the sunken areas to avoid rotting. Watering in the evening should be more careful. Watering should be controlled during the winter dormancy period to keep the pot soil from being too dry. The lower the temperature, the drier the pot soil should be. Adult large balls are more drought-resistant than seedlings. Watering should be done in the morning on sunny days in winter. As the temperature rises, the plant will gradually break away from dormancy, and the number of watering and the amount of watering can be gradually increased. Seven Fertilization Potted cacti can also be properly fertilized during the growing season, especially for those grafted with three-edged arrows, which should be given more attention to fertilization. Fertilizer can be a fully decomposed thin liquid fertilizer, applied once every 10-15 days. Pay attention to controlling fertilizer and water after autumn. Generally, it can be applied once a month, and stop fertilizing in early October. If fertilizer is not controlled. Let the cactus continue to grow. The tender ball is susceptible to frost damage during the winter. Be careful not to get it on the ball when applying fertilizer. If it gets on, spray it with water immediately. 6. Disease and insect pest control In a high temperature and poorly ventilated environment, diseases and insect pests are prone to occur. Diseases can be sprayed with carbendazim or thiophanate; insect pests can be sprayed with dimethoate. No matter which liquid is sprayed, it must be done outdoors. I hope this helps you. . .