Human Impact on an Ecosystem 2 Conservation in Fishing.

Human Impact on an Ecosystem 2

Conservation in Fishing

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Conservation

• Have you seen one of these recently? What does the phrase "dead as a dodo" mean?

• It is a Dodo and has been extinct since 1681.

• How did it happen?

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What was the dodo bird like?

• The dodo was a flightless bird that lived in the Indian Ocean island of Mauritius.

• Related to pigeons and doves, it stood about a meter tall, about 20 kgs.

• Lived on fruit and nesting on the ground.

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What happened to the dodo?

• In 1598 Portuguese and Dutch sailors were the first people to live on the island of Mauritius.

• With them they brought pigs, dogs, rats and even monkeys.

• They killed dodos for food and by 1681 (83 years later) they were extinct.

The dodo as the universally symbol of an extinct species

The dodo is commonly used as the universally understood symbol of an extinct species because its extinction occurred during recorded human history and was directly attributable to human activity.

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What is Conservation?

Conservation is the wise management of our environment to ensure the survival of organisms & their habitats.

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Benefits of Conservation

1. Existing environments are maintained

2. Endangered species are preserved for reproduction

3. The balance of nature is maintained

4. Pollution and its effects are reduced

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One Conservation practice from one of the following areas

Area Conservation Practice

AgricultureMixed farming, Crop rotation

Biological controls, Gene banksFisheries Fishing Net size, Quotas, Price of fishForestry Re-planting, Broadleaf/conifer mix

There is a need for continual monitoring of the environment to ensure its protection and the wise management of its natural resources.

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Learning Check 1

1. Do you think any more species have become extinct since the dodo?

2. Now that we are aware of the extinction of species do you think it will ever happen again?

3. Why?

4. What is conservation?

5. List some of the benefits of conservation

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Fisheries

Some of the Conservation practices from fishing are:

1.Increasing Fishing Net size

2.Assigning Fish Quotas

3.Increase the real price of fish.

4. Re-stocking

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1. Fishing Net size

What is net mesh size?

This refers to how large or small the openings or spaces enclosed by the threads of a net are.•The use of small-mesh nets can result in too many young fish being caught•Using larger meshed nets to allow the young to escape, mature and reproduce

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Different types of nets1. Square mesh netting – does not alter its shape under tension – allows young fish to escape.

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2. Diamond mesh netting – closes under tension and prevents young fish escaping.

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Learning check 2

1. What is net mesh size?

2. Name the two Different types of nets

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2. Fishing Quotas

Since 1983, the European Union has decided how much fish can be caught in its seas and oceans by each member state.

Explaining fishing quotas

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Then it is up to each national Government to decide how to divided the quotas up for:

1.specific areas,

2.seasons,

3.fisheries or

4.organisations, e.g. producers' organisations.

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Originally commercial fishing had no restrictions, but in the twentieth century over fishing of e.g. Atlantic cod and California sardines has reduced fish stocks at sea.

Why have quotas?

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1. Countries have began to limit access to their fishing grounds by boats from other countries, while

2. international organizations began to certify that specific species were "threatened", "endangered", etc.

Fish quotas (maximum amount allowed to be caught) have been assigned to different countries to ensure that enough fish are left to replenish the stock.

In response

There are limits put in place in a wide range of areas including the following:

1.Size of the fish you can keep

2.Total number or pounds you can keep

3.Total number of fish you can keep

4.Time period that it's legal to fish

5.Fishing methods

6.Fishing equipment

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Conservation and Fishing Quotas

1. Helps to prevent the extinction of a fish species

2. Gradually increases fish stock and helps to re-establish populations

3. Attempts to maintain fishing at highest possible levels

• BBC Fishing Quotas

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3. Increase the real price of fishTo provide fishermen with a decent living. Profitability in the fishery industry has been declining.

Costs have been increasing:

1.Rising diesel fuel prices

2.Costs for repairs and maintenance

Catches have declined and most operators have faced stable or falling real prices of fish due to increasing competition from other sources of fresh and frozen wild caught and farmed product. 22

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Learning check 3

1. Explain the term Fishing Quotas

2. Why have quotas?

3. Give 3 advantages of Conservation and Fishing Quotas.

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4. Re-stocking

What is the purpose of re-stocking?

Restock rivers & lakes to achieve a permanent increase in the fish population.

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Conservation and Re-stocking1. Re-stocking attempts to maintain the

balance in the ecosystem

2. Increases stocks for recreational fishing

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Give one Conservation practice from the Fishing Industry