Gill. Science. Stage 5. Aquaculture Part 1 S 43933

Transcription

1 Science Stage 5 Gill S Aquaculture Part 1 S 43933

2 Number: Title: Aquaculture This publication is copyright New South Wales Department of Education and Training (DET), however it may contain material from other sources which is not owned by DET. We would like to acknowledge the following people and organisations whose material has been used: Photographs of Fisherman, oysters, fish in a pool Barbara Gurney Front cover and Part covers 1-4 Extracts from Science Syllabus Years 7-10 Board of Studies, NSW 2003 Unit overview pp iv, v, vi and vii, viii Photograph of a Fishing boat Rhonda Caddy Part 1 p 16 Photograph of a fisherman Winifred Clipsham Part 1 p 21 (centre) Fielder, S and Allan, G (1998) Inland Production of Marine Fish, Rural Industry and Part 4 pp Development Corporation COMMONWEALTH OF AUSTRALIA Copyright Regulations 1969 WARNING This material has been reproduced and communicated to you on behalf of the New South Wales Department of Education and Training (Centre for Learning Innovation) pursuant to Part VB of the Copyright Act 1968 (the Act). The material in this communication may be subject to copyright under the Act. Any further reproduction or communication of this material by you may be the subject of copyright protection under the Act. CLI Project Team acknowledgement: Writer(s): Consultant(s): Editor Illustrator(s): Photographer(s): Desktop Publisher: Sue Benson, Winston Brown, Rhonda Caddy, John Douglas, Julie Haeusler, Maria Kersaitis, Tony Provest, Tony Waters, Jane West. Peter Bray, Phil Harding, Phil Steele Ric Morante Thomas Brown, Barbara Gurney Winston Brown, Rhonda Caddy, Tony Provest, Tony Waters Alide Schimke All reasonable efforts have been made to obtain copyright permissions. All claims will be settled in good faith. Published by Centre for Learning Innovation (CLI) 51 Wentworth Rd Strathfield NSW 2135 Copyright of this material is reserved to the Crown in the right of the State of New South Wales. Reproduction or transmittal in whole, or in part, other than in accordance with provisions of the Copyright Act, is prohibited without the written authority of the Centre for Learning Innovation (CLI). State of New South Wales, Department of Education and Training 2005.

3 Contents Part 1 Introduction Part Lesson 1 Aquaculture... 5 Aquaculture history...5 Does aquaculture affect you?...7 What did you achieve?...11 Lesson 2 Fishing up close Food pyramids...13 Science and technology changes...15 What did you achieve?...19 Lesson 3 Consuming seafood People want to eat fish...22 What did you achieve?...24 Lesson 4 Do you need aquaculture? Why are most Australians coastal dwellers?...25 Australia's aquaculture industry...27 What did you achieve?...30 Lesson 5 Aquaculture benefit Suggested answers Part Exercises Part Part 1 What is aquaculture? 1

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5 Introduction Part 1 There are probably many questions floating around in your mind as you begin a new science unit. How does it concern me? Should I care about aquaculture? Why should I learn about it? What is aquaculture? What s on TV! Aquaculture, however, is new, fresh and exciting. It may be one of the most interesting topic areas you will look into this year. It's more than just farming fish and yabbies. It s a rapidly growing industry employing thousands of people that may hold the key to solving some of the questions and concerns that have haunted scientists and politicians for many years. Concerns such as: How can we help native fish species to survive? How can we feed the world s rapidly growing population? What jobs can we do? How can we recycle valuable resources? Part 1 What is aquaculture? 3

6 Okay, now that you are interested, you are probably asking yourself, 'What is aquaculture? Where did it come from? And what's in it for me?' But you've had some clues about what aquaculture means! Look at the word again. Predict what aquaculture is. How did you go? Aqua means water and in science, culture means to grow. Aquaculture means growing animals or plants that live in water and harvesting them for food or human use. Aquatic organisms are living things that live in water. They are different to terrestrial organisms that live on land. 4 Aquaculture

7 Lesson 1 Aquaculture The idea of farming aquatic animals evolved in a similar way to farming sheep, cattle, pigs and goats. The history of aquaculture dates back many thousands of years. Until recently, it has been a relatively unorganised art form with practices, ideas and methods passed on by word of mouth. In recent times, scientific research and development have played a major role in production methods, disease control and disease management. It is no longer just a pastime or small enterprise. It is a rapidly expanding industry playing an increasingly important role in both Australia s and the world s future. Aquaculture history Looking back in time there have been many examples of aquaculture. Activity: Timeline Read the information below. Then use it to complete the following timeline. Growing fish, rather than just catching them, has been practised by humans for thousands of years. In ancient China, at least 4000 years BCE, carp were grown in the water on paddies to complement the rice crop. Two thousand years later, oyster-growing developed in Japan. It was introduced to Italy about 100 years BCE and has continued to be an important industry in tidal rivers and bays around the world. But most aquaculture is a more recent development. For example, green mussel farming began in New Zealand in Salmon have been cultivated in Europe since 1850 but Atlantic salmon farms were only begun in Australia in Trout have been farmed for a longer time in Australia, but the real breakthrough for Australian species came in 1971 when hatcheries were built to breed native species to restock Australian rivers. Part 1 What is aquaculture? 5

8 BCE carp produced in China produced in Japan oysters produced in produced in AD produced in 1971 native stock 1994 What are two generalisations about aquaculture that you can make from the timeline? Check your response by going to the suggested answers section. 6 Aquaculture

9 Does aquaculture affect you? In developed countries such as Australia, the population consumes large amounts of fresh and saltwater animals ranging from octopuses to fish and shellfish. High levels of aquatic animals are exported to other countries as well. How are you involved? 1 When was the last time you ate fish or another aquatic animal? 2 What kind of fish or aquatic animal was it? 3 Where did it come from? For many Australians, aquatic animals are part of a normal diet. If you follow health guidelines, you will include more and more aquatic animals in your meals. Most Aboriginal tribes in Australia consumed fresh and/or saltwater animals to survive. They planned their movements around seasons and used spears, hooks and natural poisons to harvest food from billabongs, rivers and oceans. hardwood bone on tip rolled bark soapy wattle or fish poison wattle (acacia holosericea) hardwood or bamboo pearl shell or kangaroo bone split bamboo fishing spears fish hook fish trap poisonous berries or roots Part 1 What is aquaculture? 7

10 Activity: Does aquaculture affect you? Why would using these types of tools have helped to limit exploitation of native fish stocks? Check your response by going to the suggested answers section. With European settlement came a rapid change in lifestyle and attitude in Australia. European populations increased rapidly and the demand on native fish stocks increased, to the point now where many native species, such as the Murray cod, Murray crayfish and catfish, are very rare in their traditional habitats. The ecological balance in these environments has been changed. Out in the ocean, humans became voracious sea-going creatures, clad in huge, technical, floating factories. Commercial fishing enterprises have devoured natural fish populations, such as nannygai, snapper, kingfish, tuna and orange roughy. These fish, that were once plentiful, are now scarce. It is not just professional fisherpeople (men and women who fish) who affect populations of aquatic animals, fishing is the number one recreational sport in Australia. Also, many aquatic animals have been caught and killed for fun. Laws have been made to limit the kind, size and number of aquatic animals that may be caught and kept in an attempt to protect aquatic animal populations. Some areas have been set aside to protect native species and where fishing is banned. What can you do? Over the last five to ten years, things have begun to change. There has been a general move away from achievement being measured by how many fish are brought home to a more sustainable catch and release strategy amongst many recreational fisherpeople. Natural fishing resources are limited and only careful management and common sense can ensure their long term sustainability. 8 Aquaculture

11 Activity: Legal, economic and scientific reasons Why should you be interested in protecting native aquatic animals? Think about the information you have just read, then write: a a legal reason (to do with the law) b an economic reason (to do with money) c a scientific reason. Check your responses by going to the suggested answers section. In recent times, attitudes to fishing and the types of aquatic animals caught have changed. Preparing for Exercise 1.1 In this exercise you will interview someone older to see if they are aware of a change in attitude in their lifetime. Choose someone such as your grandfather, mother, uncle, aunt, an older neighbour or friend. Ask if s/he could do a quick interview with you to see how things have changed in his/her lifetime. Here are some examples of questions you could ask. 1 How old are you? 2 Have you always lived in Australia? 3 Do you eat fish or shellfish? Which do you like the most? Part 1 What is aquaculture? 9

12 4 Do you enjoy fishing? Why or why not? 5 What fishing gear do you own? 6 Have you done much fishing in your life? Where? 7 What is the most fish you have ever caught in a day? What type(s) were they? 8 What did you do with them all? 9 Do you still catch that many fish? Why do you think this is so? 10 How has fishing changed in your lifetime? 11 What do you think of the new 'catch and release' philosophy in fishing today? (This is where you let the fish go without killing or hurting them.) 12 Do you think the government should do more to regulate fishing at either the commercial or recreational level? Remember to thank the person for his/her time. You may like to record your interview on a tape. There are also recording programs on most computers and you may like to use a mp3 player to record your interview. Make sure that you ask the person you are interviewing for permission to record before you start. Go to the exercises section and complete Exercise 1.1: What is aquaculture? The exercise is a recording of the interview or your report about it. If you cannot record the interview, you need to complete a brief report. 10 Aquaculture

13 What did you achieve? Tick what you can do. complete a timeline using information from text identify trends from a timeline of aquaculture explain why traditional Aboriginal fishing methods had little impact on populations of native aquatic animals identify legal, economic and scientific reasons for protecting native aquatic animals using an interview, collect and present information about changes in fishing and/or fish populations. Part 1 What is aquaculture? 11

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15 Lesson 2 Fishing up close Over the last twenty years, recreational and commercial catches have decreased at an alarming rate. Why have aquatic animal populations dropped so much? Part of the reason is that there are more people in Australia to go fishing! And part of the reason is scientific discoveries and technological developments that enable more aquatic animals to be caught for food. Fishing with technology is more efficient. Food pyramids A food pyramid represents the number of organisms in an ecosystem: a wide part means many organisms; a narrow part means few. The food pyramid below shows organisms that live in the ecosystem of the Hastings River at Port Macquarie in New South Wales. humans, pelicans jewfish, turtles, flathead, stingray whiting, mullet, bream, tailor crabs, prawns, worms, nippers, oysters zooplankton (microscopic animals) phytoplankton (microscopic plants) and water weeds Part 1 What is aquaculture? 13

16 Activity: Food pyramid Use the food pyramid to answer these questions. 1 In a food pyramid, organisms eat from the level(s) below them. a What could zooplankton eat? b What might mullet eat? c Why don't the organisms at the bottom of the pyramid (the phytoplankton and water weeds) need to eat? 2 Compare the number of turtles to the number of oysters in the Hastings River. Now imagine that the human population at Port Macquarie increases greatly. Use the food pyramid to make predictions about what might happen. 3 Humans catch and eat lots of whiting and bream they are delicious fish! Initially, what effect will this have on the numbers of: a jewfish, turtles, flathead and stingrays? b pelicans? 4 Over time, what effect would humans eating large numbers of whiting and bream have on the populations of mullet and tailor? 14 Aquaculture

17 5 What would you expect to happen if humans upset the balance within this ecosystem by overfishing (catching too many) flathead? 6 What if humans contaminated the river by chemical spillage? How might this affect the balance within this ecosystem (if the chemical stops phytoplankton from multiplying)? Check your response by going to the suggested answers section. The more people, the greater the chance that something in the ecosystem will change, altering the types and numbers of aquatic animals present. Science and technology changes Every night, thousands of commercial fisherpeople venture into Australian oceans, hunting marine life forms to provide themselves and their families with an income. Every morning, thousands of recreational fisherpeople go onto the fresh and salt waterways of Australia to have some fun, get a feed of fish, pursue a sport or fill in the day. Scientific discoveries and technological developments have ensured that these intrepid adventurers are provided with the most up-to-date equipment and methods. Gone are the days of the small wooden boat with hand lines and a rough map with some hopeful points marked on it! Part 1 What is aquaculture? 15

18 Many of today s fisherpeople, be they recreational or commercial, have large boats with powerful engines, fish finders, high technology rods and reels, and a GPS navigation system using five or six satellites to accurately tell them where they are and to take them to their favourite fishing spots day after day. Fishing has rapidly moved from a casual family adventure to an exact science driven by complex machinery and elaborate electronic instruments. 16 Aquaculture

19 The options open to commercial fisherpeople are far greater too, with onboard computers, accurate weather forecasts, mother ships, larger nets and even aeroplanes for spotting schools of fish (such as southern blue fin tuna). Activity: Changes in science and technology Here is a diagram showing some of the steps in the development of fishing equipment and techniques. spears hooks sailboats hand lines nets rods reels power boats radios paper echo sounders 4 stroke motors electronic fishfinders GPS EPIRB kevlar boat hulls 1 Circle the steps that you think used science in their development. 2 What careers involving science could be needed in the development of new fishing technologies? Try to think of at least four. (If you need a hint, look at the answer for Question 1 in the suggested answers.) Part 1 What is aquaculture? 17

20 3 Why have fisherpeople wanted new fishing technologies developed? 4 What effect do you think these new fishing technologies have had on wild fish populations? You can see that it might be helpful for a fisherperson to understand some science! If you'd like to check your answers, there are suggestions in the suggested answers. Fishing has reduced the numbers of many aquatic animals in natural ecosystems. With fewer fish, fisherpeople have to try harder and go further out to sea to maintain catch levels. Boats, equipment and methods have had to become increasingly more efficient, both to catch enough fish and to keep the cost of catching them low. Aquaculture growing of aquatic animals in a confined place rather than fishing for them is becoming an affordable way to obtain food. It will become more and more important as native fish populations decline and as the human population increases. Go to the exercises section and complete Exercise 1.2: A close look at fishing. 18 Aquaculture

21 What did you achieve? Tick what you can do. interpret a food pyramid using a food pyramid, make predictions about the impact of human activities identify careers involving science that are associated with fishing identify one positive and one negative impact of new fishing technologies Part 1 What is aquaculture? 19

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23 Lesson 3 Consuming seafood Throughout history, fishing has always been a popular pursuit. Almost everyone has some experience with fishing in their lifetime. It appeals to different people for different reasons, ranging from an adventure to employment, a sport, a lifestyle, a family outing or simply a way to relax. A huge amount of money is spent on fishing each year in Australia on boats, rods, reels, sinkers, hooks, knives and bait. The list of what you need is almost endless. From a purely financial point of view, 90% of these people would be better off going to the local fish cooperative and simply buying the fish they want! Part 1 What is aquaculture? 21

24 People want to eat fish Fish is beginning to play a far more important role as part of the staple diet for the average Australian family. Fish is high in nutrients, low in fat and a healthy part of a meal. It is generally recommended that a fish meal be eaten at least once or twice each week. Today s modern family unit is often very health conscious, aware of the different kinds of aquatic animals that can be bought and concerned about their budget. What about you? How often do you eat fish or other aquatic animals each week? The demand for a product is created by people wanting or needing the goods or service. In the case of fish and other aquatic animals, demand is created by people wanting to eat certain species. Can you use a graph to answer questions about supply and demand? The graph below shows the price paid each month per kilogram of fish at the Ballina Fish Cooperative. (Note that tiger prawns are not included in this graph because they are not caught in the Ballina area.) Activity: People want to eat fish Look carefully at this graph. Notice that it is not a normal line graph. It is a modified bar graph. The bars have been removed to make the graph easier to read. The points show the middle of the top of each bar. 22 Aquaculture

25 Average price per kilogram ($/kg) Key: king prawns snapper flathead crabs whiting 0 Jul Aug Sep Oct Nov Dec Jan Feb Mar Apr May Jun Graph of monthly fish and crustacean sales at the fish cooperative 1 What are the three main varieties of fish caught in the Ballina area? 2 For king prawns, what is approximately: a the highest price per kilogram? b the lowest price per kilogram? 3 When are king prawns in most demand? 4 What would you expect to happen to the prices if the human population doubled (there were twice as many people eating aquatic animals)? Part 1 What is aquaculture? 23

26 5 What would you expect to happen to the supply of fish, prawns and crabs if fisherpeople tried to catch more and more? Why? 6 So what would you expect would happen to the prices? Check your predictions by looking at the answers in the answer pages. Aquaculture growing aquatic animals and plants for human use can help solve supply and demand problems. Aquatic species can be grown so that the food is always available all year round. Harvesting costs can be dramatically reduced compared to open water fishing. And by increasing the size or number of aquaculture farms, the quantity of food produced can match the size of the population (provided the world does not become too overpopulated). At the same time, populations of native aquatic animals need not be disturbed by overfishing. Go to the exercises section and complete Exercise 1.3: Consuming seafood. What did you achieve? Tick what you can do. interpret a modified bar graph of sales of aquatic animals describe the effect of human population growth on aquatic animal populations 24 Aquaculture

27 Lesson 4 Do you need aquaculture? Australia is often referred to as the lucky country because it is rich in natural resources and is not overpopulated. People often think of the land as the main natural resource of our country. Our natural resources of land, rivers and oceans need to be protected as well as used. Aboriginal peoples survived on foods native to the land, rivers and oceans. Fish, kangaroo, berries, roots, bark, moths and certain leaves provided a healthy staple diet. The environment was a resource but there was a balance between use and protection. When Europeans and other immigrants came to Australia, they brought different survival methods which have degraded many ecosystems. These introduced survival methods have even completely destroyed some ecosystems. For example, the land has been damaged by salination, erosion and the extermination of many native species. Although early settlers noticed the degrading effects of their landuse methods, it took a long time for scientists and then governments to begin protecting the delicate balance within food pyramids and ecosystems. This is particularly true in the case of marine ecosystems. Rivers and oceans were often used as drains or dumps for wastes and the complex food pyramids and food webs in these ecosystems were ignored. Responsible fishing and aquaculture can be part of the way that Australians conserve and maintain the quality of our aquatic environment. Why are most Australians coastal dwellers? Aboriginal people lived all over Australia in a variety of lifestyles. Some Aboriginal people congregated when food was plentiful in an area and for social activities. But hunting and gathering in most Australian Part 1 What is aquaculture? 25

28 environments required indigenous Australians to move from place to place and no large population centres existed. When Britain took Australia as a colony, people settled around Sydney Cove. When they moved away from the First Settlement, they were more confident travelling by boat along the coastline and rivers than across land that was rough and unknown to them. Land along rivers was rich and easier to farm, and townships were established at the mouths of rivers around the Australian coastline. As Australia evolved and grew, factories were needed because the demands of the nation and its population were too great to continue to be supplied by ships from England or other foreign countries. Transport from England could take up to six months, and ships were both unreliable and very dependent on weather patterns. Products in demand include clothes, tools and farm machinery. As factories grew and industries developed, more and more products were manufactured using Australia's rich supply of natural resources. This process of establishing factories and manufacturing industries is referred to as industrialisation. It requires a workforce concentrated in an area, working in factories and shops. These people were too time poor to grow their own food, build their own homes or make their own clothes. They relied on the agricultural sector to produce extra goods to be transported to markets where they could be bought in exchange for money earned as wages and salaries. With this intensive concentration of people, large towns and cities developed and grew into areas of importance. These were usually based along rivers or at river junctions, safe ports or anchorage areas. A very popular area was where large rivers met the ocean (estuaries), creating a navigable route out to the open sea for sailing ships and steam-powered freighters. These areas are also known for an abundance of fish and aquatic animals used for food. By now, you're getting an idea of what aquaculture is and why it is important for Australia. So let's find out about Australia's current aquaculture industry and compare it with aquaculture in other parts of the world. 26 Aquaculture

29 Australia's aquaculture industry In Australia, over 60 different aquatic animal species are farmed on a commercial basis. What aquatic animals are farmed in Australia? Here are some examples of aquatic animals and where they are farmed in Australia. Species: Location: Salmon Tasmania Species: Prawn Location: All around Australia except South Australia and Tasmania Species: Southern blue fin tuna Species: Oysters Location: Port Lincoln, South Australia Location: all around Australia but types vary Species: Location: Saltwater crocodile Darwin, Northern Territory; Cairns, Queensland, Broome and Perth, Western Australia Species: Location: Giant clams Cairns, Queensland Part 1 What is aquaculture? 27

30 . Species: Location: Green-lipped abalone Tasmania; Victoria; South Australia Species: Location: Red claw crayfish Broome, Western Australia; Townsville and Brisbane, Queensland So aquaculture is important! But how do we do it? Did you imagine that there were so many and such different aquatic animals farmed across Australia? 28 Aquaculture

31 Activity: What aquatic animals are farmed in Australia? The map following shows places around Australia where aquatic animals are farmed. However, the key is incomplete. Use the information from the previous two pages to fill in the key in the map below. Add the names of the animals. Key: NORTHERN TERRITORY QUEENSLAND WESTERN AUSTRALIA SOUTH AUSTRALIA NEW SOUTH WALES VICTORIA W N E kilometres TASMANIA S These are only a few of the species and locations where aquaculture occurs in Australia. Check your response by going to the suggested answers section. Now use this information to answer the questions in the exercises. Complete Exercise 1.4: Do we need aquaculture? now. Part 1 What is aquaculture? 29

32 What did you achieve? Tick what you can do. complete a key for a map using written information identify some Australian aquatic animals used in aquaculture. 30 Aquaculture

33 Lesson 5 Aquaculture benefit Aquaculture operations bring a phenomenal amount of money into Australia through export earnings. Activity: Benefits of aquaculture Use the following pie (or sector) graph to answer the questions below. other crustaceans tuna scallops abalone rock lobsters (saltwater crayfish) pearls Export dollars earned in prawns 1 Which of the exports in the graph may have been produced by aquaculture rather than by fishing? 2 Oysters are not included in the pie graph. Why do you think this is so? 3 Rock lobsters were the biggest export for What were the next three main export products? Part 1 What is aquaculture? 31

34 Check your response by going to the suggested answers section. Aquaculture also plays a major role in helping to feed the Australian population. The aquaculture industry is helping to encourage the repair, repopulation and protection of coastal and inland waterways. Go to the exercises section and complete Exercise 1.5: Aquaculture benefits. 32 Aquaculture

35 Suggested answers Part 1 Check your responses against these suggested answers. Timeline BCE carp produced in China oysters produced in Japan oysters produced in Italy AD salmon produced in Europe 1960 green mussels produced in New Zealand 1971 native stock produced in Australia 1994 Atlantic salmon produced in Australia Part 1 What is aquaculture? 33

36 Three generalisations from the timeline are that: aquaculture has existed for a very long time aquaculture has increased quickly over the last 150 years more countries have become involved in aquaculture over time. Does aquaculture affect you? Aboriginal tribes did not overuse native fish stocks because their access to technology and fishing equipment (and their lifestyle and life philosophy) did not allow them to catch too many fish at the same time. Legal, economic and scientific reasons a b c A legal reason to protect native aquatic animals is that you could be fined if you disobey the laws to protect them. An economic reason to protect native aquatic animals is these fish are a valuable commercial resource and if they are not protected, there will be none left to catch. A scientific reason to protect native aquatic animals is that the balance of natural environments should be maintained, and that native species are becoming rarer and may disappear forever if they are not protected. Food pyramid 1 a Zooplankton could eat phytoplankton and water weeds (because these are below them in the pyramid). b c Mullet might eat anything below them in the pyramid crabs, prawns, worms, nippers, oysters, zooplankton, phytoplankton and/or water weeds. Phytoplankton and water weeds do not eat because they make their own food by photosynthesis. 2 The pyramid suggests that there will be more oysters than turtles in the Hastings River. (The pyramid shows this because oysters are below turtles, in the wider part of the pyramid.) 3 a Initially, there will be less jewfish, turtles, flathead and stingrays (because these animals will have less food if people eat lots of whiting and bream). b Initially, there will be less pelicans (because the pelicans will have less food too, as there will be less jewfish, turtles, flathead and stingrays). 4 If there are less whiting and bream, over time there will be more mullet and tailor (because mullet and tailor will have more food to eat the food that was previously eaten by whiting and bream). 34 Aquaculture

37 5 Removing too many flathead might result in a reduction in the numbers of pelicans. Initially, it could also decrease the numbers of jewfish, turtles and stingrays because pelicans would eat more of them. Over time, the numbers of jewfish, turtles and stingrays could increase because there would be more food available for them. Making predictions is complex, isn t it? That s why people need to be careful when they change things in the environment because it isn t easy to know what will happen. 6 The balance of this ecosystem would be seriously changed by a chemical spillage. All the organisms will probably be affected. If phytoplankton cannot reproduce, they will die out. There will be water weeds only to feed the animals. Some animals would die out if they didn t eat water weeds or animals that feed on water weeds. Water weeds might be overeaten and then there would not be enough food for any animals. Over time, water weeds might take over in the area. There are many, many changes that could happen. The ecosystem could be damaged severely. Changes in science and technology 1 All the things towards the bottom of the diagram, from power boats down, have used science in their development. Most of them rely on areas of physics using energy, making things move, electronics and communication technologies. You should have circled them all. What about the things above power boats? When these things were first developed, people probably didn t think about using science. But modern versions of all these things use science to develop the strong, hardwearing materials used to make them, to design the best shapes and mechanisms, and so on. 2 To develop new fishing technologies, you might need: electronics experts (to design better communication equipment) computer experts (to design better ways to control equipment and automate tasks) satellite experts (to make and put into orbit satellites to help with communication) acoustic experts (to develop better ways to use sound to find fish) geology experts (to help develop equipment to distinguish between underwater rocks and fish) marine biologists (to provide information about populations and behaviour of fish) chemists (to develop new materials, for example, that are even better than kevlar) engineers (to help design better machines). There are many, many careers involving science that could help in the development of new fishing technology! Part 1 What is aquaculture? 35

38 3 Fisherpeople want new fishing technologies so that they can catch more fish, and so that they can catch the fish they want more easily. 4 New fishing technologies have greatly reduced the populations of many wild fish. People want to eat fish 1 The three fish varieties shown in the graph are snapper, flathead and whiting. 2 a The highest price for king prawns is approximately $26 per kilogram. b The lowest price for king prawns is approximately $13 per kilogram. 3 King prawns are probably in most demand in December (because this is when the price is the highest). 4 If there were double the population, the prices of fish and crustaceans would probably increase (because there would be greater demand). 5 The supply of fish, prawns and crabs would eventually decrease if fisherpersons caught more and more of them (because there would be less animals in the wild to reproduce and grow). 6 The prices of fish and crustaceans would increase (because the demand for them would increase as they became more scarce). Pulling ideas together Three ways that Australia could benefit from an aquaculture industry are that aquaculture could produce: food for an increasing population food near main population centres products for export. What aquatic animals are farmed in Australia? Are you looking for a clue? Look at the example of aquaculture species. The first example is salmon, in Tasmania. Find Tasmania on the map and look at the way it is shaded. Then find this shading pattern in the key. Label the pattern as salmon. The next animals are prawns. They are all around Australia except South Australia and Tasmania. Now look at the map. Which pattern goes all around Australia but not across South Australia or around Tasmania? Find this pattern in the key and label it prawns. Keep matching! 36 Aquaculture

39 Key: blue fin tuna WESTERN AUSTRALIA NORTHERN TERRITORY QUEENSLAND giant clams green-lipped abalone oysters SOUTH AUSTRALIA NEW SOUTH WALES prawns red claw crayfish salmon VICTORIA saltwater crocodiles TASMANIA Benefits of aquaculture 1 Many of the products in the pie graph have been mentioned in this set as suitable for aquaculture. These could include lobsters (crayfish), prawns, pearls (in oysters), abalone, other crustaceans (such as yabbies) and tuna (blue and yellow fin). 2 Oysters may not have been included because they may not be exported (but, for your information, they are). Another reason that they do not appear could be that the value of their export is much smaller than the value of the exports of the products included (and this is the real reason). 3 The next three main exports after rock lobsters (the next three largest segments in the graph) are prawns, pearls and abalone. Part 1 What is aquaculture? 37

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41 Exercises Part 1 Exercises 1.1 to 1.5 Name Teacher Exercise 1.1: What is aquaculture? For this exercise, you have conducted an interview. Have you recorded your interview? If so, remember to send the tape or mp3 file to your teacher with this page. Will you complete a report about your interview? Use the questions below to help you recount things you learned from the interview. Make sure that you use information from your interview rather than from the examples. 1 Describe the person who you interviewed and outline his/her fishing experience. e.g. I interviewed my uncle. He's really old and used to fish a lot when he was young. He still goes fishing now and then when he gets the chance. Part 1 What is aquaculture? 39

42 2 How has fishing and the types of aquatic animals caught changed during this person's lifetime? e.g.uncle said he used to catch lots of bream (enough for his family and the neighbours) in one afternoon when he was young. Now he hardly ever catches more than one. 3 Has the person's attitude to fishing changed during his/her lifetime? Explain. e.g.uncle said that he used to fish for fun and food when he was young because it was a cheap way to get a meal. Now he really only fishes to relax though he still enjoys a good feed of fish! 40 Aquaculture

43 Exercise 1.2: A close look at fishing Here is a food pyramid for the ecosystem in the Wollondilly River. humans, cormorants rainbow and brown trout, golden and silver perch, European carp, platypus, turtles crayfish, other crustaceans, leeches zooplankton (microscopic animals) phytoplankton (microscopic plants) and water weeds Humans use trout, perch and freshwater crayfish for food. 1 How might humans affect this ecosystem? Use information from the food pyramid in your answer. 2 Suggest at least two things that humans should do to maintain the balance within this ecosystem. Part 1 What is aquaculture? 41

44 Exercise 1.3: Consuming seafood 1 Why has the number of aquatic animals caught increased? Try to think of at least two reasons. 2 What effect does this increasing demand for aquatic animals have on wild populations? 3 a What is a problem that is created by the increasing demand for aquatic animals? b Is the problem you have described a legal, economic or scientific one? Circle one answer. legal economic scientific Why did you choose this answer? 42 Aquaculture

45 4 Using the population figures below, construct a line graph using the grid supplied. The line of best fit for this graph will be a curve. Year Australian population Year Australian population million million million million million million million million million million million million million Graph heading: Year Part 1 What is aquaculture? 43

46 Using a dashed line, extend the line of best fit on your graph so that you can predict the population of Australia in 2020 and in (This is called extrapolating.) What is your prediction of the population in: a b 2020? 2040? 44 Aquaculture

47 Exercise 1.4 Do we need aquaculture? 1 Australia is often called the lucky country. Discuss this statement in relation to aquaculture. You have seen drawings of several Australian aquatic animals in the lessons. Name the animals shown below. (First try to name them without looking back through the lessons. Then check your answers.) Name: Name: Name: Name: Name: Name: Part 1 What is aquaculture? 45

48 Exercise 1.5 Aquaculture benefits 1 Name five aquaculture species shown in the pie graph below. 2 Australia s aquatic exports earned approximately $ in this period. What was the approximate value of rock lobster exports? other crustaceans tuna scallops abalone rock lobsters (saltwater crayfish) pearls prawns Export dollars earned in (Total = $ ) 46 Aquaculture