This ocean biodiversity discussion listening test page covers Section 3 of Cambridge IELTS 21 Listening Test 1 in full: the complete answer key for Questions 21–30, playable audio, an explanation for every question with the exact transcript line that proves it, and the entire recording script. Two students, Phil and Lucy, review a visiting lecturer’s talk on ocean biodiversity and then assess six resources for a seminar, so the paper mixes two Choose TWO questions (21–24) with a six-item matching task (25–30).

The answers sit in opinions, agreements and polite disagreement rather than facts, and each speaker often echoes the other before the final judgement lands. Train yourself to separate confirmed views from rejected ones with the multiple choice strategy, which governs Choose TWO questions as much as single-letter items, then check every letter against the complete Cambridge IELTS 21 Listening Test 1 answers page, which covers all four sections of the paper.

Listening Audio — Section 3

Play the recording once, without pausing, and answer Questions 21–30 before you check the key. In the real exam you hear each section exactly once.

Questions 21–30

Questions 21–22

Choose TWO letters, A-E.

21–22. Which TWO features of the lecture on ocean biodiversity had the greatest impact on the students? the references to local problems the broad focus of the examples the practical suggestions for solutions the type of issues discussed the implications for government policy

• A — the references to local problems
• B — the broad focus of the examples
• C — the practical suggestions for solutions
• D — the type of issues discussed
• E — the implications for government policy

Questions 23–24

Choose TWO letters, A-E.

23–24. Which TWO details about the research project particularly impressed the students? the team’s previous successes its wide geographical scale the use of new technology the extensive statistical evidence the large range of specialists involved

• A — the team’s previous successes
• B — its wide geographical scale
• C — the use of new technology
• D — the extensive statistical evidence
• E — the large range of specialists involved

Questions 25–30

What is the students’ opinion of each of the following resources related to ocean biodiversity?

Choose SIX answers from the box and write the correct letter, A-H, next to Questions 25-30.

• A. This is aimed at a very specialist audience.
• B. This is now rather outdated.
• C. This was an effective description of a new danger.
• D. This suggests possible ways to improve the situation.
• E. This does not give a balanced account.
• F. This is too predictable to be useful.
• G. This gives insufficient evidence for its claims.
• H. This gives a clear explanation of the problems.

25. Article on invasive lionfish

26. Documentary on microplastics

27. Podcast on ocean pollution

28. Book on coastal ecosystems

29. Article on metal toxicity

30. Podcast on floating marine cities

Ocean Biodiversity Discussion Listening Answers

Questions and Answers

Where two letters are shown for a single question, either order is accepted, exactly as in the official answer key.

Ocean Biodiversity Discussion Answer Explanations

21. B (the broad focus of the examples) — Phil contrasts national policy with the lecture itself: “The examples she gave were at a more global level”, and they showed him “how wide-ranging the threats to ocean biodiversity are”. A global, wide-ranging spread is the broad focus of the examples. Questions 21 and 22 accept the letters B and D in either order.

22. D (the type of issues discussed) — Lucy says she “especially liked the way her lecture focused on more long-term issues”, and Phil agrees with “That impressed me too”, having praised issues “likely to be important in the future”. E fails because policy change was “just at a national level”, and C fails because the conclusion offered no real solution.

23. C (the use of new technology) — Phil highlights “improvements in systems used for tracking marine animals and things like robots”, and Lucy echoes the point about robotics investigating threats. Questions 23 and 24 accept the letters C and E in either order.

24. E (the large range of specialists involved) — Phil calls it “quite unusual to have so many experts working together”, and Lucy adds they came “from such different backgrounds”. B fails because an international team is “not unusual nowadays”, and D fails because “she didn’t bombard us with figures”.

25. G (This gives insufficient evidence for its claims) — the lionfish article declared the fish environmentally dangerous, “which is probably true, but he didn’t really provide much information to explain why”. A strong claim with no supporting explanation is exactly what G describes.

26. B (This is now rather outdated) — the microplastics documentary “was made ten years ago so I gave up”, and Lucy agrees that “it was showing its age” because everyone now knows about microplastics. A ten-year-old film on a now-familiar topic is rather outdated.

27. F (This is too predictable to be useful) — the ocean pollution podcast drew the reaction “Most of it was stating the obvious”, and Phil adds that “everybody knows that anyway”. Content that tells listeners what they already know is too predictable to be useful.

28. H (This gives a clear explanation of the problems) — the coastal ecosystems book was hard going at first, but Lucy “ended up with a much better understanding of the issues”, and Phil praises “a well-written summary of those”. A book that builds understanding of windfarms and fish farms gives a clear explanation of the problems.

29. A (This is aimed at a very specialist audience) — the metal toxicity article was “way above my head”, and Lucy finishes with “and I still don’t understand it”. Material that defeats both students is written for a very specialist audience.

30. E (This does not give a balanced account) — the floating marine cities podcast “presented a rather one-sided picture”, because “it focused on how this would benefit people and ignored the effects on the environment”. Covering only one side of the question means the account is not balanced.

Listening Transcript — Section 3

PHIL: That lecture from the visiting speaker yesterday was good, wasn’t it?

LUCY: Yeah. I learned a lot from her about ocean biodiversity. I’ve already done some reading on it, and I did an assignment on some of the problems associated with it last year, but I especially liked the way her lecture focused on more long-term issues.

PHIL: Yes, things that aren’t currently receiving widespread attention but are likely to be important in the future. That impressed me too. It wasn’t exactly a feel-good conclusion because it’s hard to see any real solution for a lot of the problems.

LUCY: No, though she did point to where policy changes could be made to protect our marine and coastal environments.

PHIL: Mm. But that’s just at a national level. The examples she gave were at a more global level, and they really made it clear to me just how wide-ranging the threats to ocean biodiversity are.

LUCY: Yes, me too.

PHIL: The research project she described was impressive, wasn’t it? I’d have thought it was quite unusual to have so many experts working together.

LUCY: Yeah, and from such different backgrounds. Must have been a really exciting team to work with. I’d heard of a couple of them before – they were involved in research way back in 2009 warning about the dangers of ocean pollution.

PHIL: But now people are much more aware of that, aren’t they?

LUCY: I suppose so.

PHIL: Another thing about the research is that the team members came from all round the world. Though I suppose that’s not unusual nowadays, now everyone can work remotely.

LUCY: Right. I liked the way she didn’t bombard us with figures – I mean, they were available, but she focused more on the general points they indicated.

PHIL: Mm. And the description of improvements in systems used for tracking marine animals and things like robots were really interesting.

LUCY: Yes, and her description of how robotics can be used to investigate threats to biodiversity.

PHIL: Absolutely.

PHIL: While you’re here, can we talk about the list of resources we have to evaluate for the seminar tomorrow. I’ve had a look at them all, but it’s been a bit of a rush.

LUCY: Yeah. What did you think of that article on invasive lionfish? The one claiming they were expanding their habitat throughout the Mediterranean Sea.

PHIL: Well, the writer went on about how dangerous they were in environmental terms, which is probably true, but he didn’t really provide much information to explain why.

LUCY: I know what you mean.

PHIL: I watched the documentary on microplastics, at least I started to, but then I found it was made ten years ago so I gave up.

LUCY: I watched to the end but you’re right, it was showing its age. People had hardly heard of microplastics then, whereas now everyone knows about them and how dangerous they are.

PHIL: Yeah. Did you listen to the podcast on ocean pollution?

LUCY: Mm. I didn’t get anything out of it though. Most of it was stating the obvious.

PHIL: Yes, it mentioned pesticides and plastic and things, and it clearly made the point that they were a bad thing, but everybody knows that anyway. Did you read that book on coastal ecosystems?

LUCY: The one by John Harper? Yes, I found it hard going at first, it went into a lot of detail about things like the effects of offshore windfarms and fish farms, but actually I ended up with a much better understanding of the issues.

PHIL: Yes, I agree and I thought it was a well-written summary of those. And the diagrams helped a lot too.

LUCY: The article on metal toxicity was way above my head, I didn’t know anything about how metals from industrial emissions react in the ocean… and I still don’t understand it.

PHIL: I gave up reading after the first chapter – I just couldn’t follow it.

LUCY: That podcast on floating marine cities was interesting, though it presented a rather one-sided picture, I thought.

PHIL: Yes, it focused on how this would benefit people and ignored the effects on the environment.

LUCY: But anyway, shall we …

Key Vocabulary and Spelling

Study Tips

Treat every rejection as a cross on the question paper. The students wave away several plausible options in plain words: an international team is “not unusual nowadays”, which kills geographical scale in Questions 23–24, and “she didn’t bombard us with figures” kills the statistics option in the same item. E fails Question 21–22 for a different reason: policy suggestions existed, but “that’s just at a national level”, far short of the implications option. Strike each rejected option the moment you hear it.

In Choose TWO questions both letters earn a mark each and the pair scores in either order, so spend your checking time on whether each chosen option is confirmed, not on which box it belongs in. In the matching task the letter depends on the students’ final, agreed judgement rather than their first reaction: Phil gave up on the documentary while Lucy watched to the end, yet both settle on “it was showing its age”. Wait for the agreement, then write the letter.

Agreement language marks the answers in Section 3. Short replies such as “Yes, me too” and “I agree” confirm that the previous speaker’s judgement is the one that scores, while a follow-up such as “But that’s just at a national level” redirects the conversation and usually kills an option. Prepare by listing the six resources and predicting answers before you hear them, matching each resource to the opinion language you expect it to trigger.

Practice More Listening Tests

Turn each of the ten letters into a mark, reread the explanation for every miss, and add the result to your running total on the full Cambridge IELTS 21 Listening Test 1 answers page, which collects all four sections in one place. The free IELTS listening practice course from Simply IELTS trains the two skills this section grades: weighing a pair of answers for one question and tracking opinions across two voices. Apply both straight away with this interactive listening test: stoicism ielts listening test with answers and audio, a single-speaker change of pace, then finish the paper with Section 4, the Natural Rubber Lecture listening test.