The Australian Sea Lion

Summary:   Australian sea lions are very unique animals. They have beauty not only on the outside but also in their friendly nature and are animals that should be treated with respect. The Australian sea lion is a multipurpose mammal, from its excellent swimming abilities to its great adaptations.

---

1. Introduction
1. 1 The purpose of this report is to present all requested information, in report form, on the current status of endangered animals in Australia, for the WWF

(World Wildlife Funds). This section of the report will present all relevant information on the Australian sea lion, including. It's description, habitat, previous distribution, causes of endangerment, and what can be done to save the Australian sea lion.

1. 2 Australian sea lions are protected mammals. The Australian sea lion has been protected in different parts of Australia beginning in Western Australia in 1892, but did not receive full protection until 1987, when a law was placed to stop the hunting of the Australian sea lion for its hide and oil. Australian sea lions are considered endangered under South Australian legislation. Last century seals were hunted for their meat, oil and fur. By 1820 seal populations had reduced drastically and some breeding colonies, such as the Australian Sea Lion colony in Bass Strait, were completely destroyed. We need to protect these beautiful mammals for there unique characteristics, and because they play a part in the food chain. If the Australian sea lion was to be extinct, the food chain would be greatly affected. In summary it is obvious that the Australian sea lion is a protected animal, although many people still kill the Australian sea lion ignoring the law.
   
   
2. Description
2. 1 The Australian sea lions description is very unique because it has many different special characteristics. The Australian sea lion belongs to the Otariidae (O-tar-i-day) family because it's an eared seal. Australian sea lions are 'pinnipeds'. The word pinniped means 'fin foot', as their four legs have developed into flippers to better suit their life in water. They are marine mammals, able to swim gracefully with style. Australian sea lions have an outside earflap. However, the earflap is very small so it does not slow them down in the water. They rotate their hind flippers to face forward like a foot, and use their front flippers to push themselves up on land. This means they are very agile on land and can propel themselves forward with some speed. They use their back flippers as a rudder in water. There is only around 12 000 Australian sea lions alive today. A full-grown male Australian sea lion (better known as a bull) can measure between 2 to 2.5 metres and can weigh between 300 to 500kg, which is about three times heavier than females. The bulls have dark brown fur with a pale neck. Females weigh about 200 to 250kg and measure between 1.3 and 1.8 metres. They have grey fur on their back with creamy fur on their front.They are very social animals and will tend to gather in groups, particularly during the breeding season. Males come ashore and battle for territories during this time, before females come ashore 2-3 weeks later. Males may keep possession of over 80 females, although 4-6 females are more typical. A female will give birth to a pup after an 18-month cycle, this length of time is very unusual. The baby sea lion is born with a chocolate brown coat and will weigh about 6.3kg and measure between 50 and 75cm, often they will go off to explore on their own. The Australian sea lion loves to play and has a very friendly nature. They only feed at sea on squid, cuttlefish, octopus, fish and rock lobsters, and are expected to eat 14-27% of their weight in food per day. They have a life expectancy of approximately 30 years, if they survive their first 6 months. Their bodies are specially adapted for water, to help them swim and dive. They are streamlined. The nostrils close underwater immediately to block out any unwanted water. The pupils of the eyes expand widely so they can see in the dark deep underwater. The Australian sea lion can stay underwater for up to 2 hours, storing oxygen in their muscles. Underwater, their heart rate also slows down and arties squeeze shut, this allows the sense organs and nervous system to get the only normal blood flow. From the information above it's easy to see that the Australian sea lion is a multipurpose mammal, from its excellent swimming abilities to its great adaptations.
2. 2 The Australian sea lion is a very important mammal to ecology. The Australian sea lion is part of the food chain. Many animals depend on this mammal as food, such as sharks. If Australian sea lions were to be extinct or have very few numbers then sharks would lose a vital amout of food. This outcome is not good as the food chain could be greatly affected. Greater animals would then become extinct because of no food source. This relates to humans, as human beings rely on certain animals to provide food. In summery we need Australian sea lions to live, and the Australian sea lion needs us.
3. Habitat
3. 1 The Australian sea lions environment is very unique and can differentiate depending on the time of year. It is one of the very few mammals that live solely in Australia. This unique seal is found from the Houtman Abrolhos Islands, 500km north of Perth in Western Australia to the waters east of Kangaroo Island, South Australia. They are located in cool but not cold waters, spending most of their onshore time on beaches, offshore rocks and islands. In summary the Australian sea lion requires a particular habitat to survive. Therefore the Australian sea lion is best living in the cool waters of the sea or on warm sands on an island.
3. 2 The Australian sea lion previously inhabited many more areas than today. Before the Australian sea lion was heavily hunted for it's hide and oil in the 18th and 19th centuries, it extended as far as the islands in Bass Straight, near Tasmania. Back then the Australian sea lion had a population of around 35 000, which is about 3 times more the population than today. In conclusion the Australian sea lions population and habitat has obviously decreased over time.
4. Endangerment
4. 1 Australian sea lions have many factors that contribute to their decreasing numbers. When sealers and whalers heavily hunted the Australian sea lion in the 18th and 19th centuries for their hide, oil, meat, and blubber, their distribution greatly declined. A great danger to the Australian sea lion is accidentally getting entangled in fishing nets, particularly gill nets, and crayfish pots, which is one of the main threats to the species due to being strangled and suffocating. Another is their unique breeding cycle. An Australian sea lion will give birth after an 18-month cycle, and will only produce one pup. They also have a reputation for bad mothering; a mum can leave its very young pup alone for hours, possibly days.
4. 4. Throughout this time they can be harmed by bulls (males), which have no problem in harming the little pups if they get in the way. Another possibility, is that the Australian sea lion may be facing stronger competition for food from their cousin, the New Zealand fur seal, whose numbers are increasing on Kangaroo Island (one of the breeding and living places for the Australian sea lion) at an annual rate of around 10%. Fisheries today also threaten marine mammals by fishing for the same food that the animals depend upon to live. In many places, Australian sea lions are seen as competition for fish and are poisioned and killed to keep fish for the humans. Australian sea lion are also threatened by oil tanker spills, these spills pollute the water that certain mammals inhabit. Therefore Australian sea lions are very variable
   4. 2 The Australian sea lion has many culprits that kill this beautiful mammal. The main culprit that has killed the Australian sea lion is man. Man kind; have killed sea lions for centuries, merely for their fur, meat and oil. We have now reduced them to such a number that it's almost impossible to get their original population back. The Great white Shark is also killing the Australian sea lion. The favourite food of the Great white Shark is the Australian sea lion. Australian sea lions are slow swimmers compared to most seal and sea lions, so they make easier prey. As shown in the information above Australian sea lions have many culprits.
   5. Strategies
   5. 1 There are many strategies that can take place immediately to save the Australian sea lion. One of them is reducing boat speed. Boats are not only a threat to the Australian sea lion, but to all marine life. Boat propellers often strike seals and sea lions when they come up to the surface to breathe. The boats are often going so fast that they don't have time to react to a creature in front of them. This leaves the Australian sea lion, or any another animal, defenceless and badly damaged, often leading to their death. A law should be placed immediately that reduces the speed allowance of boats near marine life. If people come across this tragic problem, often they will not stop and help. Even giving awareness of any problem may help to immediately reduce the Australian sea lions mortality rate.
   5. 2 Australian sea lions need protection from fishing nets immediately. Over 200 Australian sea lions die from suffocation a year, from getting caught in these fishing nets. This tragic outcome is a result of fishermen allowing their fish net holes to be too big. A law could take action in around 6-12 months that states no net holes can exceed the distance of around 3cm. This allows fishermen to catch suitable fish, without the odd seal or sea lion being caught. Fishing areas should regularly be patrolled by boat police to make sure this law takes place.
   5. 3 The Australian sea lion has a breeding cycle of around 18-months. Since this period is so long, it contributes to their endangerment. More breeding programs can help to increase the Australian sea lions population. This would not take effect for more than 12-months due to their breeding cycle, but would definitely have an impact. Conservation Parks such as Seal Bay are already taking appropriate action on this problem, by having breeding programs of their own.
   5. 4 Certain measures of the ones listed above would have better results than others. Reducing the net holes would have the best effect. This kills the majority of Australian sea lions each year and reducing this problem would gain a lot of the population back. Although reducing the speed of boats and having more breeding programs would help, these measures are not as fast and would not have as great an effect as reducing net size.
   6. Modern wild life parks: Currumbin Sanctuary
   6. 1 Seal Bay Conservation Park has used many different conservation methods to protect the Australian sea lion. Located in South Australia's Kangaroo Island. Seal Bay supports the third largest colony of Australian Sea Lions with a population of approximately 700 (5% of the worlds total). This sanctuary was proclaimed in 1954 and parts of colonies that managed to survive earlier threats began to breed here. These Australian sea lions are placed in a constructed habitat, specially devised for their needs. This area is in captivity were they can breed in peace and be safe from certain humans who can cause disturbance in their lifestyle. They have learnt to accept people and provide visitors with a close wildlife encounter not available elsewhere in the world. However, they can be dangerous and have been known to attack tourists, so the entrance is restricted to minimise disturbance. The whole bay is an aquatic reserve in which swimming and fishing are prohibited to better suit the sea lions needs. Not only are they protected in the sanctuary, but also there is an aquatic reserve, which restricts fishing along the full length of the park and for 1 km out to sea. Seal Bay also does research programs. Lately they have placed plastic flipper tags on each sea lion to identify and monitor their breeding methods. They are also studying their diving patterns. This involved attaching a small instrument known as a time/depth recorder to the back on several Australian sea lions. In summary the Australian sea lion is a well known species that people need to take care of. Conservation parks such as Seal Bay, help in keeping these endangered animals alive.
   6. 2 Seal Bay Conservation Park is a very successful wildlife reserve. Seal Bay Conservation Park has successfully been able to collect information on the Australian sea lion by conducting numerous experiments. These experiments are conducted to find their breeding cycles, diving duration and life expectancy.
   6. 3 Seal Bay hopes in the future to produce a better understanding of the Australian sea lion, by taking research programs one-step further. They also plan on increasing awareness of the interrelationship of humans and the environment. Wild life parks, such as Currumbin Sanctuary also have hopes for the future. They are planning to breed the Australian Bilby in captivity. In summary, wildlife parks are working hard to protect endangered animals.
   7. 0 Conclusion
   7. 1 Australian sea lions are very unique animals. They have beauty not only on the outside but also in their friendly nature and are animals that should be treated with respect. The Australian sea lion is a multipurpose mammal, from its excellent swimming abilities to its great adaptations. They were previously populated in a lot more areas, prier to hinting. Currumbin Wildlife Sanctuary and Seal Bay Conservation Park are working to preserve animals just like the Australian sea lion, so they have a better chance at surviving from harmful threats in the future. The Australian sea lion is a well known species that people need to take care of. It's a tourist icon; up there with the koala, which attracts tens of thousands of visitors to the sea lion colonies each year.