Buzz
Islands are known for a variety of reasons. Some attract visitors due to their unspoiled beaches, perfect waves for surfing, and vibrant snorkeling reefs. Others are famous for their volcanic landscapes, breathtaking hiking routes, or the presence of native tribes.
These 10 islands stand out due to their exceptional animal populations. Some of these species draw travelers from all corners of the globe, some are safeguarded from human interaction, while others might be best avoided.
10. Grand Cayman's Green Iguanas
Grand Cayman, the largest of the Cayman Islands, has been overrun by green iguanas. These reptiles, native to Central and South America, were introduced to the island in the 1980s. Initially brought as pets, they quickly spread in the wild.
While green iguanas are generally peaceful herbivores, they pose a significant threat to the island. Their presence endangers Grand Cayman’s natural resources as they strip tree bark, damage gardens and farms, and compete with local species for food. With the island already overwhelmed, authorities worry about their potential spread to Little Cayman and Cayman Brac.
To curb the invasion and protect nearby islands, the Department of Environment is exploring ways to eradicate these iguanas. Before 2010, killing iguanas was illegal in Grand Cayman, but exceptions have been made for the invasive green iguana species.
From May 2016 to November 2017, registered hunters were compensated $2 for each green iguana they removed. During this period, over 8,500 iguanas were eliminated from Grand Cayman. However, with the population nearing one million, this effort has had little effect.
9. Christmas Island’s Red Crabs
Located atop an ancient volcano in the Indian Ocean, this Australian territory is renowned for its vibrant red crustaceans. Christmas Island is the exclusive home to the Christmas Island red crab, a species found nowhere else on Earth.
Approximately 40 to 50 million red crabs inhabit Christmas Island. For most of the year, they reside in the rain forest, feeding on the fallen leaves and fruits. During the dry season, they dig burrows to escape the heat and maintain their moisture. The wet season, which typically begins around October or November, marks the start of their annual migration to the coast to breed.
Timed with the phases of the Moon, adult males are the first to head to the shore, where they dig ‘mating burrows.’ Soon after, females follow. During this period, Christmas Island becomes a sea of red crabs as they travel to the coastline. To protect the crabs, roads along busy paths are closed, and tunnels are constructed to ensure safe passage.
After mating, the male red crabs return to the rain forest, while females stay for about two weeks before releasing their eggs into the ocean. Four weeks later, the baby crabs emerge from the water and follow their parents' path inland.
8. Seal Island
Seal Island, located in False Bay off the coast of Cape Town, South Africa, is a reserve with no sandy shores or vegetation. However, it is teeming with Cape fur seals, and their population is estimated to be around 75,000.
Uninhabited and off-limits to tourists, Seal Island still bears the remnants of huts used by sealers in the early 1900s, as well as a damaged World War II radio mast, marking past human activity on the island.
While Cape fur seals continue to be hunted in some countries, such as neighboring Namibia, they have been protected in South Africa since 1973. However, they are not free from danger. During certain seasons, especially in winter (June to August), the waters around Seal Island are infamous as the 'Ring of Death.' Great white sharks prowl the area, hunting for seals as their next meal.
Although visitors are not allowed on the island itself, boat tours around False Bay offer the chance to see the Cape fur seals basking in the sun or swimming in the bay. For the adventurous, cage diving during high shark activity provides an up-close experience with the seal-hunting great whites.
7. Isle Royale’s Moose and Wolves
Isle Royale, the largest island in Lake Superior, Michigan, is home to the world’s longest-running predator-prey study. This national park and biosphere reserve has been the site of ongoing research into the interactions between moose and wolves since 1958.
Neither moose nor wolves are native to Isle Royale. It is believed that the moose swam to the island in the early 1900s, while the wolves arrived across the frozen lake sometime in the mid-1900s.
Approximately 1,600 moose reside on Isle Royale, while the wolves that prey on them have dwindled to a mere two. The recent decline in the wolf population has allowed the moose numbers to rise dramatically. Over the past six years, the moose population has grown by an average of 20 percent annually. Scientists are concerned that this increase may negatively impact the island’s vegetation, particularly if the moose population continues to grow at such a rapid pace.
As for the wolves, the island once supported a pack of around 30, but only two remain today. Their decline is largely due to severe inbreeding. The last two wolves are father and daughter, sharing the same mother. Researchers note that the two have attempted to mate on at least one occasion.
In 2015, a pup was seen with the remaining wolves, but the pup showed noticeable health issues, including a malformed tail and other unusual physical characteristics. The pup has not been seen since and is presumed to have died. It is highly unlikely that the remaining wolves will be able to produce healthy offspring.
A plan to reintroduce additional wolves to Isle Royale is currently under review.
6. Wild Horses of Assateague Island
Assateague Island is home to about 300 wild horses. Located off the coasts of both Maryland and Virginia, the island is shared by both states. Two-thirds of the island belong to Maryland, while a fence marks the border with the Virginia section of the island.
The horses are divided into two herds, one for each state. The Virginia herd is known as the 'Chincoteague ponies,' while the Maryland herd is referred to as 'Assateague’s wild horses.' Technically, these 'wild' horses are feral, having descended from domesticated horses that reverted to a wild state.
Some argue that the Chincoteague ponies should be considered horses rather than ponies, but they were officially recognized as a breed, the 'Chincoteague Pony,' in 1994. On average, Assateague Island horses are smaller in height, falling within the pony range rather than horse. This smaller size is believed to be the result of their diet, which mainly consists of marsh grasses that provide little nutrition.
The origin of how the horses came to live on Assateague Island is unclear. One local legend suggests they survived a shipwreck long ago. Proponents of this theory point to the area's history of shipwrecks and the practice of transporting horses by boat. Alternatively, others believe the horses were brought to the island in the late 1600s by landowners who wanted to avoid fencing laws and livestock taxes.
The horses on Assateague Island are a major attraction, but it's crucial to remember they are not domesticated animals. Each year, there are incidents where visitors who get too close to the horses end up being kicked or bitten.
5. Henderson Island Rats
Henderson Island is a remote coral island located in the South Pacific. While there are no human inhabitants, the island is home to a unique range of wildlife, including birds, invertebrates, and plants found nowhere else on Earth. However, the island also faces a significant rat infestation problem.
Polynesian rats were brought to the island by sailors around 800 years ago. Today, researchers must be cautious with their food packaging, as these rats can chew through tents to reach food. The rats also prey heavily on baby chicks, with about 95 percent of chicks hatched on Henderson Island being consumed by rats within their first week of life. This includes the endangered Henderson petrel, a ground-nesting seabird.
In an effort to protect the island's native species, a plan was put into action to eradicate the rats. In 2011, 80 tons of rat poison pellets were dropped across the island. Initially, the poison seemed successful, with the rat population dwindling to fewer than 100.
However, the plan did not completely eliminate the rat population, and these rodents breed rapidly. A female rat can give birth to a litter of six pups every few months, and the female pups reach maturity in just two or three months, starting their own litters. As a result, the rat numbers on Henderson Island have swelled back to between 50,000 and 100,000—about the same as before the poisoning.
4. Tonawanda Island Cats
A small island in New York’s Niagara River, Tonawanda Island is sparsely populated by humans but is overrun by a large population of stray cats.
A few years ago, Tonawanda Island was overwhelmed by hundreds of neglected and sick cats. While some of these felines may have arrived on the island by their own means, there were reports of people simply abandoning their unwanted cats there. These cats created a nuisance by leaving waste everywhere and climbing aboard docked boats at the marina, causing a foul odor on the island.
Danielle Coogan, a resident of North Tonawanda on the mainland, visited the island’s well-known restaurant in 2014. Shocked by the state of the cat population, she decided to take action. Coogan started a highly successful fundraiser called 'Operation Island Cats.'
With the funds raised, Coogan and a team of volunteers trapped, neutered, and vaccinated the cats living on the island. Kittens were placed up for adoption, while older cats were returned to their natural home. Now, the Tonawanda Island cats are protected from rabies and other common feline diseases, and they no longer contribute to the birth of stray kittens.
Although the Tonawanda Island cats were thriving, they faced a setback in 2016. The raised funds had also been used to set up shelters and feeding stations on the island. During the spring of that year, after a marina fire, a crew working at the restaurant inadvertently bulldozed nearly all of the cat shelters and feeding stations.
The restaurant owners have stated that the damage was unintentional. Thankfully, no cats were harmed in the incident, and Coogan has been working to raise funds to replace the destroyed shelters and feeding stations.
3. Año Nuevo Island Of Love
Año Nuevo Island, located just 0.8 kilometers (0.5 miles) off the coast of Northern California, is a nine-acre sanctuary that boasts one of the highest concentrations of animal life on the planet. Two centuries ago, the island was once connected to California's mainland by a narrow peninsula. However, as water levels rose, the rocky landmass became isolated, and it served as a Coast Guard light station from 1872 until 1948.
Presently, Año Nuevo is a bustling haven for wildlife, serving as a vital breeding ground. The island is part of a reserve, and access is limited to research purposes only. Scientists visiting the island quickly learn that the animals do not appreciate their presence. Seagulls dive-bomb them with droppings, and researchers must crawl on their bellies to avoid disturbing sea lions and causing a chaotic stampede.
The northern elephant seal has thrived the most on Año Nuevo Island. In the past, elephant seals were abundant in the Pacific Ocean, with populations numbering in the hundreds of thousands. However, during the 1800s, they were hunted relentlessly for their blubber, and by 1892, only about 50 to 100 elephant seals remained.
Año Nuevo Island became a sanctuary that helped northern elephant seals avoid total extinction. The first elephant seal was recorded on the island in 1955, and six years later, the first pup was born there.
Since then, the island has served as a critical breeding and birthing location for northern elephant seals, with up to 2,000 pups born there annually. Today, the population of these seals has grown to nearly 160,000.
2. Lambay Island Wallabies
In a surprising twist, wallabies, a marsupial species native to Australia, are flourishing on an island off the coast of Ireland.
Lambay is a private island located 14,500 kilometers (9,000 miles) from the natural habitat of wallabies. In their native Australia, wallabies enjoy warmer temperatures, while the climate on Lambay Island rarely exceeds 15°C (60°F).
The island does feature rocky cliffs and steep terrain that appeal to wallabies, and they've adapted to the cooler environment by growing thicker coats of fur. As naturally shy animals, wallabies seem to thrive in the tranquility and solitude of this secluded island.
In the 1950s, the island’s owners introduced wallabies among other species, including tortoises and lizards. The wallabies were the only non-native species that managed to survive. Later, in the mid-1980s, seven more wallabies were sent from a Dublin zoo that could no longer house them.
The exact number of wallabies on Lambay Island before that is unclear, and it remains difficult to estimate their current population since none are tagged. Due to their secretive nature, counting them is tricky, but it's believed that between 30 and 50 wallabies currently inhabit the island.
1. Okunoshima Rabbits
Okunoshima, a small island situated just 3 kilometers (2 miles) off the coast of Japan, is often called Rabbit Island due to its large, friendly population of wild rabbits.
There are different theories about how rabbits came to live on Okunoshima. One suggestion is that they were abandoned when the island was a secret military base during World War II. At that time, Okunoshima was excluded from maps, and it served as a site for producing deadly chemical weapons. It is believed that rabbits were brought to test the effects of these chemicals.
However, many experts disagree with this story. They believe that the rabbits used for testing were eradicated, and none survived to establish a free-roaming population on the island.
Another theory is that a school trip to the island in 1971 inadvertently led to the release of a few rabbits. With no natural predators to keep their numbers in check, the rabbit population grew rapidly, reaching about 1,000 today.
Tourists flock to the island to see the rabbits, but this growing popularity is causing harm. Feeding the rabbits has led to an overpopulation, and the island struggles to provide enough resources for them.
Moreover, rabbits are not designed to cope with irregular feeding patterns. Their digestive systems are disrupted when they feast on food provided by visitors on busy days but are left to forage on their own during slower, weather-challenged days.
