Mud Islands facts for kids
 Mud Islands
Location in Melbourne
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| Geography | |
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| Location | Port Phillip |
| Coordinates | 38°16′S 144°46′E / 38.267°S 144.767°E |
| Administration | |
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Australia
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| State | Victoria |
The Mud Islands are a special group of islands found inside Port Phillip in Victoria, Australia. They are about 90 kilometers (56 miles) southwest of Melbourne. These islands are located 10 kilometers (6 miles) inside Port Phillip Heads. They are also 7 kilometers (4 miles) north of Portsea and 9 kilometers (5.6 miles) east of Queenscliff.
The land area of the Mud Islands is about 50 hectares (124 acres). It is made up of three low-lying islands. These islands surround a shallow, tidal lagoon that is about 35 hectares (86 acres). The lagoon connects to the sea through three narrow channels. The shapes of the islands can change over time. This happens because sand moves around due to ocean currents.
Contents
History of Mud Islands
Europeans first saw the Mud Islands in 1802. They were first called Swan Isles. This was because many swans lived in the waters around them. Later, in 1836, two lieutenants from a ship called HMS Rattlesnake surveyed the islands. They then renamed them Mud Islands.
Protecting the Islands
In 1961, the Victorian Fisheries and Wildlife Department made the islands a sanctuary. This meant they were a safe place for the White-Faced Storm Petrel bird. In 1979, the land above the high water mark was declared a permanent reserve. This was to help manage and protect the wildlife there.
The Mud Islands are part of a very important wetland area. This area is called the Port Phillip Bay (Western Shoreline) and Bellarine Peninsula Ramsar Site. It is recognized as a wetland of international importance. The islands are also listed on the Register of the National Estate. Since 2002, the islands and the waters around them have been part of the Port Phillip Heads Marine National Park. This park helps protect the marine life and habitats.
Island Environment and Wildlife
The Mud Islands are home to many different plants and animals. The environment here is very unique.
Island Plants (Flora)
There are nine different types of native plant communities on the islands. These include Seagrass meadows, sand dunes, mudflats, and salt marshes. These habitats support many living things. They range from tiny marine invertebrates to fish and birds.
The wind and tides slowly change the shape of the islands. However, some plants help keep the islands stable. These include salt marsh plants like austral sea-blite and beaded and shrubby glasswort. In the past, there was a lot of thick coastal scrub on the northern island. This scrub has disappeared. It seems that too many rabbits eating the plants caused this. Today, only one coastal teatree remains.
Island Animals (Fauna)
The Mud Islands are part of the Swan Bay and Port Phillip Bay Islands Important Bird Area. This area is recognized by BirdLife International as crucial for birds. About 70 different types of birds have been seen on the islands. The islands are very important for seabirds and waders. Many of these birds are migratory, meaning they travel long distances. The islands provide essential places for them to breed, feed, and rest.
Seabirds and Their Reproduction
The islands are isolated, which means they are safe from predators. This makes them a perfect sanctuary for breeding seabirds. One important bird is the white-faced storm-petrel. About 5,500 of these birds lay their eggs in burrows in the sand of Middle Island during summer. During the day, they feed on shrimps and small fish at sea. At night, they return to feed their chicks. The Mud Islands are home to nearly a quarter of all white-faced storm-petrels that breed in Victoria.
Silver gulls are even more common. In the second half of the 1900s, their breeding population grew to about 100,000 birds. Gulls can sometimes attack the eggs and young of other seabirds. Scientists are studying how this affects the other birds.
Other seabirds that nest on Mud Islands include nearly a thousand crested terns. This is one of the largest colonies in Victoria and the only one in Port Phillip. There are also about a dozen breeding pairs of Caspian terns. In 1983 and 1986, several pairs of Australian pelicans also bred here. Little penguins and fairy terns have bred on the islands in the past. The common tern also rests here in very large numbers. As many as 260 common terns have been seen at one time.
Waders and Their Feeding Habits
The mud that gives the islands their name is a great place for migratory waders to find food. Waders are birds that wade in shallow water to feed. More than 1% of the known Australian populations of four wader species spend the summer around Mud Islands. These include the Pacific golden plover, grey plover, lesser sand plover, and ruddy turnstone.
More than 5% of Victoria's populations of red knot, great knot, eastern curlew, and bar-tailed godwit feed in Swan Bay to the west. They then fly to the islands to rest at high tide. Two types of waders live on the islands all the time. These are the pied oystercatcher and the red-capped plover. They regularly breed in the undisturbed parts of the islands.
Other Interesting Animals
Few land birds live permanently on the islands. However, many species visit and might breed there. Large numbers of straw-necked ibis and Australian white ibis nest and rest on the islands. They fly to the mainland every day to find food. The Lewin's rail sometimes breeds in the salt marsh. This bird is very shy, so its nesting is rarely seen.
Up to 100 rare orange-bellied parrots have been seen on the islands during winter. They migrate from Tasmania to the Australian mainland. However, their numbers have gone down since the mid-1900s. This might be because more gulls have changed the soil chemistry. This affects the plants the parrots eat. Still, the islands are an important home for this endangered species. Bronze whaler sharks are also known to breed in the waters around the islands.
How to Visit Mud Islands
You can only reach the Mud Islands by boat. The easiest places to leave from are Queenscliff or Sorrento. You are allowed to visit during the day, but you cannot camp overnight.
BirdLife Australia offers regular tours to Mud Islands, usually in February and March. South Bay Eco Adventures also runs guided walking tours of the islands. The waters around the islands are shallow, so visitors need to be careful when landing. Passengers usually have to be taken to shore by a small boat (dinghy) or wade in. You need to plan your visit carefully so your boat does not get stuck at low tide.
