2, flies

3. Crow

4. dung beetles

5.seagulls

6, ants

1, "scavenger": native to Latin America, belonging to Silurus, also known as sucker fish, miscellaneous fish, anglerfish and anglerfish, with a large body, a flat head, a towering dorsal fin, a flat tail and a developed mouth and lips, resembling a sucker. The whole body is covered with shield scales and the body surface is rough. The body is grayish black or light brown with black and white patterns on the body surface. Strong physique, easy to raise. The inlet water temperature is 22~28℃, and the water quality is weak alkaline hard water. The bait is mainly algae, but also live food. In the aquarium, it is often adsorbed on stones and glass to stabilize the body, suck algae and look for benthic animals (such as water worms). It is a loyal "cleaner" in the aquarium. It belongs to nocturnal fish and can be mixed with healthy fish. It is difficult to breed in an aquarium. "Scavengers" are omnivorous fish, which can eat 3,000 to 5,000 fish eggs a day and swallow a large number of fry, threatening the reproduction and growth of other fish. At present, scavengers have no natural enemies in rivers.

2. Flies, which are annoying and want to be extinct, have made great contributions to environmental protection. Think about it. In the wild, except for some dung beetles, the feces of almost all animals are digested by fly larvae.

Another example is the carcasses of animals. Except for a few scavengers, most of them are disposed of by flies. If there were no flies, it would be obvious how much air in the fields would be polluted by the decay of corpses, and the probability of disease spread would be greater. The existence and significance of an animal cannot be based on human likes and dislikes. So flies have made great contributions to the environmental protection of the earth.

3. Crow: You are the scavenger of nature; Crow, you clean up the debris;

4. dung beetles (dung beetles): dung beetles rolls a dung ball. Dung beetles are very interesting If they find human or animal feces, they are made into dung balls. When making dung balls, they first pile the dung together with their heads, and then beat the dung into a ball with their front feet. At this time, "husband and wife" work together, one pulls in front and the other pushes behind, so that the dung ball rolls forward. After rolling to the predetermined place, the female dung beetle digs a hole in the dung ball with her head and feet, lays her eggs in it, then pushes the ball into the hole dug in advance and buries it with soil. Hatched larvae feed on dung balls until they become pupae in the soil. This is why dung beetles roll dung balls, which can not only make them thrive, but also prevent environmental pollution.

5. Seagulls: Seagulls feed on coastal insects, mollusks, crustaceans and worms and grubs in cultivated land; They also prey on small fish on the shore and pick up leftovers discarded on the shore and on ships. Some large seagulls prey on eggs and young birds of other birds (including their own kind).

Seagulls are the most common seabirds. In the coastal areas, seaports and fishing grounds rich in fish and shrimp, flocks of seagulls float on the water, swimming, foraging and flying at low altitude, and like to cluster in food-rich waters. Seagulls not only eat fish, shrimp, crabs and shellfish, but also like to pick up leftovers discarded by people on board, so seagulls are nicknamed "harbour cleaners", and ports, docks, bays and ships are almost its frequent visitors. On the ship's route, seagulls will follow, and even walking on the beach at low tide will wake up a group of seagulls.

6. Ants: The feeding habits of ants vary greatly from species to species. Generally, it can be divided into carnivorous, phytophagous and omnivorous ants. Omnivorous ants are in the majority.