Part 4: Australian Crocodiles
Part 4
Questions 31-40
Complete the notes below
Write ONE WORD ONLY for each answer.
Questions 31-40
Complete the notes below.
Write NO MORE THAN TWO WORDS for each answer.
Research methods:
– This research is world-leading because 31 ………………………. is used in the study.
– In previous studies, the tests were done with 32 ………………………
– Problem of the old device: always losing 33 ……………………………..
– The crocodiles are not easily captured, as they are cautious and try to avoid being followed by
34 …………………….
– A tracking device is attached to the 35 ……………………. of the crocodile.
Relocation of crocodiles:
– Scientists relocate the crocodiles by using a 36 …………………
– Relocated crocodiles follow the most 37 ……………………… route home.
– Crocodiles can find their way because they have ability to 38 …………………..
Conclusions:
– The crocodiles find their direction by using their senses to the 39 …………………………..
– Crocodiles have the same migration system as 40 ………………………
Key
- satellite
- radio
- signals
- human/humans/human beings
- head
- helicopter
- direct
- navigate
- sun
- birds
Transcript
Speaker: You will hear part of a lecture about the study on Australian crocodiles.
Lecturer: Around 10 years ago, Australia Zoo, the University of Queensland and Queensland Parks and Wildlife, undertook a project to monitor the movements
and behaviour of the crocodiles in Lakefield National Park. The aim of the study was to provide better information on how adult crocodiles there interact within a river system, enabling people to have better decisions on how to manage crocodile populations.
Modern Tracking Technology
Lecturer: This project can lead the world in crocodile management because of the use of satellite, which enables scientists to stably receive accurate information being sent back to them on the computer. Even though the crocodiles can travel very long distances, scientists can still know where they are and study their habits. The study is going to help scientists gain further knowledge on crocodile behaviour, which can help make informed decisions on the management plans for crocodiles not only in Australia but around the world.
Previous Tracking and Challenges
Lecturer: Crocodile tracking isn’t a new idea in Australia. Crocodile studies have been previously conducted by radio. A miniature electronic device was implanted under the skin of these animals and they were released back into the river. These tags enabled scientists to track the movements of these particular crocodiles over the next 10 years.
Lecturer: Of course, there are some unexpected challenges. The data transmitted from each receiver is recorded by some devices employed in the receiving stations. However, some devices are too old that they always lose signals due to a variety of reasons. So they can’t track those animals which they have been studying for months.
Lecturer: In order to study the crocodiles, they must first be captured so that the device can be put on them. But this is a very difficult task because they are alert and afraid of being followed by humans. So it might take the team several hours to capture one.
Lecturer: The tracking device has signal transmitters inside and it’s waterproof. It is attached to the head of the crocodile so the crocodile cannot remove the device with its feet or tail.
Research Findings
Lecturer: The research has begun to reveal the movements of crocodiles.
- Data showed that crocodiles tend to be more active at night time.
- The GPS sometimes shows that in some areas the crocodiles are overpopulated. So scientists at the park have to use a helicopter to relocate the crocodiles in order to control their population in the area. A crocodile would be taken many kilometres away from its original place.
- However, scientists found that the relocation methods were ineffective, because the relocated crocodiles will return to their original location following the most direct route within one week. The tracking data shows that the crocodiles swim right back to where they came from when moved.
- Crocodiles sometimes travel hundreds of kilometres from Indonesia to Australia in order to reproduce. It is interesting to see that they can always find their way and they will not get lost in the ocean. Scientists realised the crocodiles are able to navigate. This is an important ability for them when they have to migrate for very long distances.
- Scientists conclude that crocodiles can tell directions by using their senses to the sun so that they know where they are going. This is an ability which human beings don’t possess.
- Another finding is that, like the migration of birds who can travel thousands and thousands of kilometres, crocodiles have the same system to help them travel.
Lecturer: The research is still going on in northern Australia. Scientists are working hard to gather more information about this amazing creature.
