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Johnston Atoll

geography Maturity 11-13

Johnston Atoll is a group of islands.

Johnston Atoll 2.jpg
Johnston Atoll 2.jpg
It is in the big ocean. It is near Hawaii. Many birds live there.
Juvenile Red-footed booby 01 USFWS.jpg
Juvenile Red-footed booby 01 USFWS.jpg
They make nests on the land. The birds are happy there. Do you like birds?

44 words

Johnston Atoll is in the North Pacific Ocean.

Johnston Atoll 2.jpg
Johnston Atoll 2.jpg
It sits near the islands of Hawaii.
Midway.jpg
Midway.jpg

The atoll has four islands. Some islands were made by moving coral.

Growth of Johnston Island.svg
Growth of Johnston Island.svg

Many seabirds live on the islands. They make nests in the sand.

Juvenile Red-footed booby 01 USFWS.jpg
Juvenile Red-footed booby 01 USFWS.jpg

The water has many kinds of fish. Colorful fish swim near the reefs.

Butterflyfish at Johnston Atoll NWR (5123998092).jpg
Butterflyfish at Johnston Atoll NWR (5123998092).jpg

It is a special place for nature. Teams work hard to keep it safe.

85 words

Johnston Atoll sits in the North Pacific Ocean.

Johnston Atoll 2.jpg
Johnston Atoll 2.jpg
It is located between the Marshall Islands and the Hawaiian Islands.
Midway.jpg
Midway.jpg
This atoll is a ring of coral reef. It has four islands in total.

Two islands are natural. These are Johnston Island and Sand Island. The other two islands are not natural. People made Akau and Hikina islands by moving coral.

Growth of Johnston Island.svg
Growth of Johnston Island.svg

The weather here is tropical and dry. The land is mostly flat with some palm trees. There is no natural fresh water.

Many animals live here. The atoll is a great home for seabirds.

Juvenile Red-footed booby 01 USFWS.jpg
Juvenile Red-footed booby 01 USFWS.jpg
It has the world's largest group of red-tailed tropicbirds. Many fish live in the warm water too.
Butterflyfish at Johnston Atoll NWR (5123998092).jpg
Butterflyfish at Johnston Atoll NWR (5123998092).jpg
You might see green turtles or monk seals.

For a long time, the U.S. military used the islands. They used them for many things. This left some pollution behind. Teams worked to clean the area by 2004. Now, they watch the land to keep the wildlife safe.

187 words

Johnston Atoll is a special place in the North Pacific Ocean.

Johnston Atoll 2.jpg
Johnston Atoll 2.jpg
It sits between the Marshall Islands and the Hawaiian Islands.
Midway.jpg
Midway.jpg
This area is an unincorporated territory of the United States. The U.S. Air Force manages the land today. Because it is a protected area, the public cannot visit. You need a special letter to enter the islands. You also need a permit to go into the surrounding waters.
ISS012-E-17436 - View of the Johnston Atoll.jpg
ISS012-E-17436 - View of the Johnston Atoll.jpg
These waters are part of a National Wildlife Refuge.

The atoll is made of a coral reef platform. It has four islands in total. Two of these are natural features called Johnston and Sand Island. The other two islands, Akau and Hikina, are artificial. People created them by using coral dredging to move sand.

Growth of Johnston Island.svg
Growth of Johnston Island.svg
This work made the islands much larger than they used to be. By 1964, the total land area reached 267 hectares. The islands are mostly flat and have a low elevation. There is no natural fresh water on the land.
Aerial view of Johnston Atoll and Sand Island.jpg
Aerial view of Johnston Atoll and Sand Island.jpg

The history of the atoll involves many different groups. A ship called the Sally first hit the reef in 1796. Later, Captain Charles James Johnston gave the islands their name in 1807. In 1858, people claimed the atoll to find guano for farming. The United States took control of the area later on. The military has used the atoll since 1934. They used it as a refueling depot and an airbase.

USS Tanager (AM-5).jpg
USS Tanager (AM-5).jpg
It was also used as a site for testing weapons. These activities caused pollution that people had to clean up. The Air Force finished cleaning the area in 2004.

Many amazing living things call this atoll home. It is a very important place for seabirds.

Johnston Atoll Seabirds FWS.jpg
Johnston Atoll Seabirds FWS.jpg
The atoll has the world's largest colony of red-tailed tropicbirds. There were 10,800 nests found there in 2020.
Juvenile Red-footed booby 01 USFWS.jpg
Juvenile Red-footed booby 01 USFWS.jpg
You can also find many types of fish in the coral reefs.
Butterflyfish at Johnston Atoll NWR (5123998092).jpg
Butterflyfish at Johnston Atoll NWR (5123998092).jpg
About 300 species of fish live in these waters. Green turtles and Hawaiian monk seals also visit the area. Even humpback whales might swim through these waters sometimes.

Today, teams work hard to protect the natural environment. They monitor the land and the sea to keep wildlife safe.

A dog sniffs for invasive crazy ants at Johnston Atoll Refuge.png
A dog sniffs for invasive crazy ants at Johnston Atoll Refuge.png
In the past, yellow crazy ants were a big problem for the birds. These ants were killing the seabirds, but they were gone by the 2020s. The weather here is tropical but usually quite dry. The northeast trade winds blow consistently across the atoll. There is very little change in temperature throughout the year. This helps keep the environment steady for the animals that live here.

485 words

Johnston Atoll is an unincorporated territory of the United States located in the North Pacific Ocean.

Johnston Atoll 2.jpg
Johnston Atoll 2.jpg
It sits between the Marshall Islands and the Hawaiian Islands, southwest of the island of Hawaiʻi.
Midway.jpg
Midway.jpg
The atoll is under the jurisdiction of the United States Air Force (USAF). Because it is a restricted area, the public is not allowed to enter. Access for management requires a letter of authorization from the USAF. People also need a special use permit from the United States Fish and Wildlife Service (USFWS) to enter the surrounding waters. These waters are part of the Pacific Islands Heritage Marine National Monument and a National Wildlife Refuge.
ISS012-E-17436 - View of the Johnston Atoll.jpg
ISS012-E-17436 - View of the Johnston Atoll.jpg

The geography of the atoll is shaped by a coral reef platform. Originally, the atoll consisted of only two islands named Johnston and Sand Island. Over the 20th century, humans changed the shape of the land through coral dredging. This process of moving coral created two new artificial islands named Akau (North) and Hikina (East).

Growth of Johnston Island.svg
Growth of Johnston Island.svg
By 1964, these operations had significantly increased the size of the original islands. Johnston Island grew from 19 hectares to 241 hectares. Sand Island grew from 4 hectares to 9 hectares. The two new islands added 10 and 7 hectares respectively. This brought the total land area to 267 hectares.

The climate at Johnston Atoll is tropical but generally dry. It is classified as a hot semi-arid climate. The atoll receives just over 800 millimeters of annual rainfall. Consistent northeast trade winds blow across the area. There is very little seasonal variation in temperature. The terrain is mostly flat with an elevation ranging from sea level to Summit Peak. There are no natural freshwater resources on the islands. The vegetation is limited to some low-growing plants and palm trees.

The history of the atoll involves many different maritime and political shifts. The first Western record occurred in 1796 when the American brig Sally ran aground on a nearby shoal. In 1807, the islands were sighted by a Royal Navy ship commanded by Captain Charles James Johnston. The islands were later claimed by the United States under the Guano Islands Act of 1856. This act allowed citizens to claim uninhabited islands containing guano, which is used for fertilizer. In 1858, the Kingdom of Hawaii also attempted to claim the atoll, naming it "Kalama." However, the United States maintained sovereignty over the area.

USS Tanager (AM-5).jpg
USS Tanager (AM-5).jpg

Since 1934, the United States military has controlled the atoll. During this time, the site served many different purposes. It was used as a naval refueling depot and an airbase. The military also used the atoll as a testing site for biological and nuclear weapons.

Bluegill Prime Thor Missile Explodes.JPG
Bluegill Prime Thor Missile Explodes.JPG
It served as a secret missile base and a location for storing chemical weapons, including Agent Orange. These activities caused environmental contamination across the area. The USAF worked to remediate this contamination and completed the process in 2004. Today, the military performs only periodic monitoring of the site.

Despite its history of military use, the atoll supports significant marine and avian biodiversity. The surrounding waters host about 300 species of fish.

Butterflyfish at Johnston Atoll NWR (5123998092).jpg
Butterflyfish at Johnston Atoll NWR (5123998092).jpg
Green turtles and Hawaiian monk seals also visit the reefs. The area is recognized as an Important Bird Area by BirdLife International. The atoll holds the world's largest colony of red-tailed tropicbirds, with 10,800 nests recorded in 2020.
Juvenile Red-footed booby 01 USFWS.jpg
Juvenile Red-footed booby 01 USFWS.jpg
Many other species, such as the great frigatebird, also use the atoll for breeding.
Johnston Atoll Seabirds FWS.jpg
Johnston Atoll Seabirds FWS.jpg

Modern management focuses on protecting this delicate ecosystem from invasive species. In the 21st century, yellow crazy ants became a major ecological problem. These ants were killing the native seabirds. However, teams worked to manage the threat, and the ants were eradicated by the 2020s.

A dog sniffs for invasive crazy ants at Johnston Atoll Refuge.png
A dog sniffs for invasive crazy ants at Johnston Atoll Refuge.png
Today, USAF and USFWS teams continue to conduct environmental monitoring. They work to maintain the habitat and protect the native wildlife from further harm.

689 words
🖼️ Images & Media (26)
File:Midway.jpg
Midway.jpg
File:Growth of Johnston Island.svg
Growth of Johnston Island.svg
File:Butterflyfish at Johnston Atoll NWR (5123998092).jpg
Butterflyfish at Johnston Atoll NWR...
File:Juvenile Red-footed booby 01 USFWS.jpg
Juvenile Red-footed booby 01 USFWS.jpg
File:Johnston Atoll Seabirds FWS.jpg
Johnston Atoll Seabirds FWS.jpg
File:Johnston Island Reservation EO 4467 illustration.png
Johnston Island Reservation EO 4467...
File:USS Tanager (AM-5).jpg
USS Tanager (AM-5).jpg
File:Whippoorwill (AT-O--169).jpg
Whippoorwill (AT-O--169).jpg
File:Compiled image of aerial photographs taken of Sand-Johnston island, 1964. (10055259966).jpg
Compiled image of aerial photographs...
President Nixon's Visit, Johnston Island,...
File:Aerial view of Johnston Atoll and Sand Island.jpg
Aerial view of Johnston Atoll and Sand Island.jpg
File:Johnston Atoll 2.jpg
Johnston Atoll 2.jpg

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