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Christmas Island with a magnificent baby boom grip

Millions of red crabs landed on Christmas Island, and locals used leaf blowers to save large numbers of crabs from traffic.

Bumper breeders are better news for the island’s most famous inhabitants and will further increase the explosive population in recent years.

Recently, scientist Tanya Det spent about five hours a day, fixing a blower on her back and airbrushing baby crabs off the road as people headed to work or stores.

Some locals even break their blowers and hand her hot and exhausted work.

It’s a bit like trying to leave the Red Sea, says Dr. Dett.

“They are very light and fly only a little. They don’t get hurt, they just keep walking when they land.

“But they move so fast that by the time you blow one small section, what’s behind already fills the gap, so you have to stay right in front of the car.”

In addition to her traffic management duties, Dr. Dett is responsible for calculating the number of red crabs that now call Christmas Island home.

Given that millions are added to the mix in a good year, it’s not an easy task-and there are a lot of them these days.

Based on a survey conducted at the end of last year, she estimates that the population has surged from about 40 million in 2015 to about 190 million.

“Basically, after 2013/14, we started getting a lot of very big baby returns that we didn’t get 20 years ago,” she said.

“I don’t know why … but it should have something to do with the swells, currents and ocean conditions of the island when the baby is there.”

Christmas red crabs are land crabs, but they need the sea to breed.

Towards the end of each year, adult crabs leave the forest house inside the island and march towards the coast.

When the tide is high, the female jumps into the shallows and violently “shake her boots” to release the egg bag.

They hatch almost immediately and the larvae disappear into the sea and return as megalops 3-4 weeks later. This is the final stage of the life cycle where you can breathe underwater.

After hanging out in the shallows for a week or so, they completely transform into crabs, dashing towards the woods, turning all patches on the ground and roads into rippling live carpets.

Young crabs stay in the forest for four to five years until they are mature enough to participate in the annual coastal migration.

Dr. Dett says that crabs found only on Christmas Island and, to a lesser extent, the nearby Cocos Islands, have also been successful thanks to efforts to combat the invasive yellow crazy ants.

Yellow crazy ants were first discovered on the island in the 1920s, but only became a problem in the late 1980s when the first supercolonies were formed.

Ants have killed tens of millions of red crabs over the years by spraying them with powerful formic acid.

However, invaders are now less common after scientists have deployed microwasps to prey on insects that have historically provided abundant food sources for ants.

Christmas Island with a magnificent baby boom grip

Source link Christmas Island with a magnificent baby boom grip

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