Christmas Island and the millions of migrating red crabs
Christmas Island is a pretty interesting place in our planet. In addition to the beautiful tropical nature, here, at a certain time, you can watch a truly amazing phenomenon – the migration of millions of crabs.
Australia is not only a continent and a separate country. It also includes many islands. And some of them lie far from its coast. Christmas Island is just such a thing. It is located in the eastern part of the Indian Ocean and is the Australian Outer Territory.
An interesting fact is that some countries have territories far beyond its borders. A prime example is the island of Réunion. This is an overseas territory of France, which lies at a distance of more than 9,000 km from Paris
Christmas Island on the map
- Geographical coordinates ( -10.487955, 105.637330 )
- The distance from Canberra, Australia is about 5200 km as a straight line.
- The nearest airport is located directly on the island in its north-eastern part. It is called Christmas Island Airport
- 350 km to the coast of Java
- From the coast of Australia about 1600 km
The island is of volcanic origin and is actually the top of an ancient volcano. The coastal shoal is from 200 meters to 5 kilometers off the coast, further the depth increases sharply up to 5 km.
For hundreds of kilometers around there is not a soul. Christmas Island is one of the most secluded and remote places on Earth.
Let us remind you that our planet has a lot of remote, but very interesting places. For example, the island of Saint Helena, where Napoleon Bonaparte found his eternal rest. Or the island of Tristan da Cunha, which lies thousands of miles from the nearest mainland.
Christmas Island in numbers.
- A rather curved coastline with a total length of about 139 km
- The size of the island is about 18 by 17.5 km
- The area – 135 km 2
- The highest point of the island is 361 meters above sea level
The capital is the town of Flaming Fish Cove in the northern part of the island with a population of about 1500 people (the total population of the island is slightly over 2000 people). It is noteworthy that Australian citizenship is only about 600 people. The main population is Chinese. They are almost 65% of the population. 20% – representatives of European races, 10% Malays and 5% Indians and other nationalities.
The religious composition is also quite diverse and is mainly represented by Buddhism, Christianity and Islam. Despite the fact that people on the island of different faiths, they live very amicably. Together they celebrate all holidays and Christian Christmas, and the Chinese New Year and Muslim Uraza Bayram. The Chinese, Malay and English languages are spoken mainly.
Christmas Island Climate
The island’s climate is distinctly tropical, with the classic dry and wet seasons. Humidity is high, about 80-90%. The average annual temperature is of the order of 27 o C. And the difference between the seasons is minimal. The only difference is the amount of precipitation. In winter, during the rainy season there are about 300 mm of precipitations, while in summer the figure drops to 40-45 mm per month. The total annual rainfall exceeds 2100 mm.
A bit of history
The island gets its name from the fact that it was discovered on Christmas Day in 1643. The first European to set foot on the island in 1688 was William Dampier, a British navigator. The island was a British colony from 1900 but was occupied by Japan during World War II. Since 1958, the island was given to Australia and is administered by the Australian government.
In 1888, deposits of calcium pyrophosphate were found on the island. Since 1895, active mining began and a permanent population appeared. But in 1987, the deposits were depleted and phosphate mining was stopped.
Now the main part of the island’s income comes from the tourist business. Many cruise lines pass through Christmas Island.
The island is rich in flora and fauna. Thick rainforests with ferns, vines, and orchids cover most of the island. 18 plant species are endemic. Flying foxes, bats, many birds and several species of crabs inhabit the island.
Migration of crabs on Christmas Island
The most interesting feature of this place, lost in the ocean, is the annual seasonal migration of millions of red crabs.
Christmas Island Red Crab Migration
Adults of this crab species have no natural enemies on the island (but the yellow crazy ant can attack the young), so the population has grown to incredible sizes.
Most of the time, red crabs live in forests and on the coast, but every year around November, natural instincts drive millions of individuals into coastal waters to lay eggs and continue their lineage. Scientists estimate that up to 100 million crabs a season migrate across Christmas Island.
This phenomenon is recognized as one of the wonders of the world. The crab migration is getting a lot of attention from tourists and authorities alike.
Tourists are very interested to see this unique natural phenomenon, and it is very important for the authorities to protect the migrating crabs during the breeding season. To do this, they even close roads and install special signs warning of migration.
In some places, special crossings have been built for the crabs, strikingly similar to traditional overhead crosswalks.
Above-ground crab crossings on Christmas Island
The population density of crabs on the island is many times greater than that of humans. It is estimated that an average of 3-5 crabs per 10 m 2 live on Christmas Island.
Christmas Island red crabs
In addition to this natural phenomenon, travelers will enjoy beautiful beaches and a rich natural world. There are plenty of fish in the coastal waters, you can take the time to fish.
Fishing on Christmas Island
You probably have seen more than once on the Internet reports about how during the seasonal migration, for 10 days, millions of land crabs go to the coast to sweep the eggs. This amazing spectacle attracts the attention of ecologists and photographers from all over the world.
Christmas Island is a relatively small (135 sq. km) volcanic island in the Indian Ocean belonging to Australia, which owes its name to its discovery by the British on Christmas Day in 1643. The main attraction of the island is the annual migration of 100 million red crabs (Gecarcoidea natalis), during the mating season, which occurs around mid-October to January, set off on a multi-day journey from the rain forest to the shores of the Indian Ocean, covering everything in their path: roads, grounds, yards and buildings with an orange-red carpet.
It is difficult to predict the exact date of migration; it all depends on when the wet season begins. It takes about 18 days for the crabs to reach the shore. One of the most impressive natural migrations takes place – the synchronized movement of tens of millions of crabs for several kilometers.
Let’s have a closer look at it .
The earth red crab (Gecarcoidea natalis) is a species of crustacean that lives only on Christmas Island
As you can see from the photo, the name of the species was not chosen by chance. This land crab is bright, saturated red color, and not boiled. That’s how nature painted it. The migration of the red crab is the main attraction of this island. During the 20 days of the seasonal migration, about 150 million red crabs move to the coast to spawn. This is nature’s most spectacular migration.
Photographers and environmentalists from all over the world come every year to see this amazing spectacle.
The migration takes place from mid-October to January, during the mating season. There is no exact date for the migration, it all depends on the beginning of the wet season. Under the canopy of torrential rains, earth red crabs embark on a multi-day journey to the shore of the Indian Ocean and cover everything on their way (roads, buildings, grounds, yards) in red-orange color. Their movement is synchronized over several kilometers.
The males are the first to move to the shore. Upon reaching the shore, they fight among themselves for territory. After that they burrow into the sand and wait for the females. Females reach the shore in 12-15 days. When the last phase of the moon arrives, the females lay eggs.
The average body size of a red crab is about 20 centimeters. Most of the time, during the dry season, they live in their burrows in the moist, dense forest. They go out only in the evening, at sunset, in search of food.
An amazing fact: in normal times red crabs move very little, no more than 10 minutes at a time, but during the mating season they are able to move for many days kilometers. Biologists from the Universities of Bangor and Bristol studied in detail for three years the reason for this sudden ability of crabs during the breeding season.
After a series of experiments with the fluid circulating in the red crab’s body (analogous to human blood), they concluded that with the onset of mating season, the red crab has a greatly increased level of a hormone (crustacean hyperglycaemic hormone).
Thanks to this hormone, reduced activity in crabs turns into hyperactivity. The energy stored in the muscles begins to work. Nature has adjusted this process so that the available energy reserves are used as efficiently as possible.
The red crab is exposed to several major dangers during its seasonal migration.
One significant danger that could lead to the complete extinction of this crustacean species is the relatively recent emergence of crazy yellow ants. Moving through the territory inhabited by supercolonies of ants, the crabs start to disturb them. The ants, in turn, start throwing formic acid at the crabs. Because the density of ants per square meter is quite high, they are capable of destroying the crabs in their territory 100% in just 24 hours.
Therefore, the number of red crabs in these areas has become almost zero. In the last few years, according to scientists’ calculations, the number of crustaceans has fallen by about 20 million. And the ant population is steadily increasing. This situation can lead over time to the complete disappearance of this unique crustacean species. That’s why red earth crabs have been listed in the International Red Book.
It is believed that in recent years, huge colonies of ants have killed 15 to 20 million crabs. Meanwhile, the ant population continues to grow. If this continues, this unusual crustacean species could be endangered.
2. The second threat to migrating crabs is cars. When crossing the highway during migration, about one million crabs die under the wheels of vehicles. To reduce these losses certain measures are taken: Along the roads special fences are built.
Special underpasses and bridges are built for the safe movement of crabs. They are excellent climbers, which allows them to easily climb steep walls and rocks.
At the peak of migration, certain roads are blocked and signs are put up to warn of migration.
The third danger is the dehydration of red crabs. Red crabs are unique sanitarians. They keep the island perfectly clean by eating: rotting fruit of fruit trees, fallen leaves, giant snails, rotting fruit fruits, and outdated bird corpses.
Along with red crabs, 15 other species of crustaceans, such as coconut crabs and palm thieves, coexist on the island. They reach a size of up to 40 centimeters and weigh up to 4 kilograms. With their powerful claws, they can easily crack coconuts and even break bones.
Crabs are not very large (average body length is 20 centimeters) and not very active – during the dry season they spend most of the time in their holes in the litter of wet forests, getting out only at sunset to find food.
During their migration 700 thousand to 1 million animals die under the wheels of automobiles.
This is probably the end of this difficult hike
I once at a seaside restaurant in France. Of course it was original, but I didn’t like it much as a meal. As entertainment – yes, but not as food
And here’s more about the interesting crabs: here’s an interesting Spider Crab for example, and here’s the most beautiful COCKOS Crab. Let’s see, what is the biggest arthropod on the planet and what are the two-colored arthropods. And, of course, the History of the Creation of Crab Sticks.