Seal Island (Investigator Strait) facts for kids
 Seal
Location in South Australia
|
|
| Geography | |
|---|---|
| Location | Investigator Strait |
| Coordinates | 35°20′19″S 136°55′13″E / 35.33848°S 136.92017°E |
| Highest elevation | 35 m (115 ft) |
| Administration | |
|
Australia
|
|
Seal Island is a small island in South Australia. It's found in Investigator Strait, off the southern coast of the Yorke Peninsula. The island is about 7 kilometers (4.3 miles) southwest of Stenhouse Bay. Since 1972, Seal Island has been a protected area, part of the Althorpe Islands Conservation Park.
Contents
What is Seal Island Like?
Seal Island is often described as a raised "hump" of land. It reaches a height of 35 meters (115 feet) above the sea. On its western side, there are several smaller, separate islets. The easiest way to visit Seal Island is usually from its northern coast. It's best to go when the weather is very calm.
Is Seal Island Part of a Group?
Many people think of Seal Island as part of a larger group of islands. This group includes the Althorpe Islands and Haystack Island. Together, they are known as the Althorpe Islands Group.
How Seal Island Was Formed
Seal Island was created a very long time ago, between 7,500 and 8,900 years ago. This happened when sea levels rose at the start of a period called the Holocene. The rising water separated the Yorke Peninsula from Kangaroo Island, leaving Seal Island behind.
What is Seal Island Made Of?
The island is mostly made from the remains of a type of rock called granite. On top of the granite, there's a layer of another rock called Bridgewater Formation calcarenite. Over time, the ocean has worn away much of this calcarenite. The sea around Seal Island is quite deep. It drops to 20 meters (66 feet) within 300 meters (980 feet) of its western and southern shores.
Plants and Animals on Seal Island
Seal Island is home to various plants and animals. Scientists have studied the island to see what lives there.
What Plants Grow on Seal Island?
A survey in 1996 found 10 different types of plants on the island. These included:
- Nitre-bush
- Grey Samphire
- Roundleaved Pigface
- Sea Celery
- Marsh Saltbush
- Ruby Saltbush
- Australian Hollyhocks
What Animals Live on Seal Island?
The 1996 survey also found several types of birds living on the island. These included:
At that time, scientists thought Galahs and Australian sea lions might just be visiting. However, later studies showed that Australian sea lions do use the island. They use it as a place to rest on land, which is called a haul-out area. They might even use it as a place to have their babies, known as a rookery. The Crested tern has also been seen on the island.
Protecting Seal Island
Seal Island is an important place for wildlife, so it has special protections.
Why is Access to Seal Island Restricted?
Since 1972, Seal Island has been part of the Althorpe Islands Conservation Park. This means it's a protected area. Since 2007, it has been a "prohibited area." This means you can only visit the island if you have a special permit. This rule helps protect the seabirds that breed there.
How are the Waters Around Seal Island Protected?
Since 2012, the waters around Seal Island are also protected. They are part of a "sanctuary zone" within the Southern Spencer Gulf Marine Park. This helps protect the marine life in the ocean around the island.
