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Part A :

Today we're going to be looking at the ecological impact of the feral camel in Australia.

As you know, a feral animal is one that survives in the wild even though it originally lived with people,

in a domestic situation.

Camels are not native to Australia,

so how did they get here or, more importantly, why?

The importation of camels began in 1840 and continued through to 1907.

They were brought here to aid in opening up the arid and semi-arid regions of inland Australia.

Initially they provided transport for people and goods involved in exploration or mining in the outback.

They were also used to carry equipment for the construction of railways and telegraph lines.

And often, they were the only way many remote settlements could receive supplies.

Where did they come from ?

Well, curiously enough,

from as far afield as China and Mongolia - that was the large, woolly,

two-humped Bactrian camel - and of course there were dromedaries (the typical Arabian camels used primarily for riding);

but most of them were fro,n lowland India.

These ones, in particular,

were very large and powerful and they were used to carry or move heavy freight.

What we have noware feral camels that are mixtures of. these different breeds.

Why are they feral?

Well, once the railways were up and running and motor vehicles were becoming more common in the outback,

they weren' t needed any more.

So, many of the 20,000 or so domesticated camels that were around in 1930 were just let go.

And because they were so well adapted to desert conditions,

they thrived and bred and spread right across central Australia.

What' s the problem? You might ask.

After all they' re just camels living in the desert.

The problem is that they are an introduced animal - a very large one at that - and they do extensive damage to the desert eco - system.

They wander up to 70 kilometres in one day,

grazing on whatever vegetation is available - that might be grass, shrubs or trees up to 3.5 metres high.

In times of drought,

when water is scarce,

they are capable of drinking up to 200 litres each in three minutes,

although if they're consuming a lot of green moist plant material,

they don't need that much.

They gather around precious water holes to get this water,

and the degradation of these water holes is of serious concern.

They are crucial for the survival of a wide variety of native animals and plants.

Many of these are now threatened to the point of extinction.

Let me also point out that these watering places have a long-standing cultural significance,

and many of them are sacred sites for the Aboriginal people.

Feral camels are literally trampling all over and violating Aboriginal traditions and history. In periods of extreme drought,

like Australia has experienced in recent years,

there is no limit to their quest for water.

Camels are big animals,and they go pretty much wherever they please.

They are not primarily interested in hurting people,

but it's not advisable to get in their way.

They have gone into remote communities and damaged domestic infrastructure such as washing facilities in laundries and bathrooms

as well as outside bores,taps and tanks.

Let's see: feral camels have a negative impact on native vegetation and animals,

water supplies, and Aboriginal and outback communities but they are no friends of the farmers, either.

They compete with livestock for pasture and they can wreck the farmer's precious property in the process,

knocking down fences, windmills and water troughs.

Camels also carry some of the same diseases as livestock and are likely to spread infection among cattle and other farm animals.

On top of all that, they cause a number of collisions with trains, cars and trucks.

Oh, and one more thing,

camels are ruminants,

which means they emit methane,

and they are having a significant impact on climate change.

Feral camels do have some value as a resource.

There is a small export market in camel meat,

and the pet meat trade uses them as well.

Although camels have a reputation for being stubborn,

and even vicious,

they are easy to domesticate once they are captured.

We don't use them in industry any more,

but sometimes they are used by tourist operators as a novelty form of transport for their customers. Even so,

it would seem their usefulness is limited and far outweighed by their overall -harmful - economic, environmental,

social and cultural impact.

Complete the sentences below.


显示答案 正确答案: dometic     

Complete the sentences below.


显示答案 正确答案: equipment     

Complete the sentences below.


显示答案 正确答案: (heavy) freight     

Complete the sentences below.


显示答案 正确答案: central Australia     

Complete the sentences below.

35 Problems caused by feral camels

- roam over large areas eating all kinds of plant material

- can drink enormous amounts of water: litres in 3 minutes

显示答案 正确答案: 200|two hundred     

Complete the sentences below.

36 - damage sensitive areas and threaten the survival of native species

- damage water holes that are for Aboriginals

显示答案 正确答案: sacred(sites)     

Complete the sentences below.

37 - enter . and destroy domestic facilities such as bores and tanks

显示答案 正确答案: remote communities     

Complete the sentences below.

38 - damage farm property, e.g. fences, . and water troughs

- carry disease and cause accidents

- produce methane

显示答案 正确答案: windmills     

Complete the sentences below.

39 Feral camels as a resource

Camel meat is exported and also used by the trade.

显示答案 正确答案: pet meat|pet-meat     

Complete the sentences below.

40 They can be captured, domesticated and used in tourism for

显示答案 正确答案: transport