The mouse grows and invades an island in just 5 months

The male pair of mice left on an island takes only 5 months to proliferate and invade the whole island.

Only in 5 months does the mouse multiply and invade an island

According to the BBC, invasive pests are a major problem for ecological conservation . Exotic species can threaten the survival of local animals, possibly even changing the ecosystem where they invade. This problem is particularly serious on islands, where water is isolated.

Wilson's extinct bird species were extinct by mice.(Photo: Michael Stubblefield / Alamy)

Invasive species often follow the foot of humans and extinct species on the island. Over the past 500 years, rodents and cats have extinct to 70 bird species. In January 2015, a large-scale rat killing campaign was carried out on the island of South Georgia , far south of the Atlantic Ocean. The rats here are the culprits of extinction of 90% of seabirds, including the black seagull and the Wilson leopard. They broke into the bird's nest, eating eggs and young birds.

To experiment, scientists dropped a pair of mice on Saddle Island, 6 hectares wide, about a kilometer from New Zealand . The island is isolated by the sea, with only sand dunes and steep cliffs, with forests but no freshwater reserves. The island was invaded by rats, however, they were completely destroyed in 1989.

Rats are species with a very fast growth rate.(Photo: A&J Visage / Alamy)

The two selected mice were native New Zealand, with an average lifespan of about 18 months in their natural environment. They grow up after 6-8 weeks of age, give birth to an average of 6 children each and the time between two litters is 20-30 days.

After two months, the number of rats was 14 and after 5 months was 68. According to calculations by scientists, this is the largest number after 5 months possible, under given conditions. It is noteworthy that the original two mice were released from the south-north of the island, separated by 400 m. That means before they can mate, it takes time to find each other.

When testing mice after 5 months, scientists found 14 different hybrids, in which the females initially contributed significantly to the explosion of the population. Many hybrids between mother and son, or male and female.

In addition, the experiment also shows that preventing rodent entry is a difficult task. Scientists discovered, not all mice on the island are descended from the original two mice. There are a number of other females that are crossed between the original male and a third female, which may already be available on the island.

According to the researchers, the mouse is not a good hand to swim. Therefore, it may be the descendants of the mice on the island, accidentally following the tourists and fishing here.

This study shows that the rate of rapid growth of rats, while emphasizing the importance of preventing the invasion of an alien species , before they reach the amount of control and change of the system Ecology of a place. The mice after the experiment ended will be destroyed, returning the status quo to the island.