Band 8.5 model answer: problem and solution

A band 8.5 model answer to a real IELTS Writing Task 2 question, with the paragraph plan that fits it. Aim for 250 to 290 words in 40 minutes.

The question

In many countries, wild fish stocks are declining due to overfishing, while fish farming (aquaculture) is rapidly expanding to meet demand. What problems does this situation create, and what measures could be taken to address them?

Your 4-paragraph plan

Introduction (40-50 words). Paraphrase the issue and preview that you will cover causes and solutions.
Body paragraph 1 (80-100 words). The main cause or problem, with a specific example of its effect.
Body paragraph 2 (80-100 words). One or two realistic solutions, saying who should act (government, schools, individuals).
Conclusion (40-50 words). Summarise the problem and your strongest solution.

The trap in this question type

Vague solutions like 'raise awareness' score poorly. Name who acts and what exactly they do, then say what changes as a result.

Band 8.5 model answer

454 words, the length a strong candidate produces in the 40 minutes Task 2 allows (the minimum is 250). Written for this exact question in the official format. Read it once for ideas, then write your own before comparing.

The depletion of ocean fish populations, coupled with the rise of aquaculture as a substitute source of supply, is not a simple case of one industry replacing another. Each side of this shift carries its own set of difficulties, and both need to be tackled if seafood is to remain a viable food source for a growing population. The decline of wild stocks creates problems that extend well beyond the fishing industry itself. Coastal communities in places such as Senegal, where small-scale fishing crews have historically supplied local markets, find their catches shrinking as industrial trawlers from wealthier nations strip nearby waters. This threatens both livelihoods and food security, since fish often provides the cheapest source of protein available to poorer households. At the same time, the collapse of key species disrupts marine food chains, since predators and scavengers that depend on those fish are left without a reliable source of prey. Aquaculture, meanwhile, brings a different cluster of problems even as it fills the gap left by wild catches. Farmed salmon operations in Norway and Chile, for instance, often rely on densely packed pens that foster outbreaks of sea lice and disease, both of which can jump to nearby wild populations. Feed for carnivorous farmed species is frequently made from wild-caught fish meal, which means aquaculture can end up placing further pressure on the very stocks it is meant to relieve. Waste and chemical runoff from farms also degrade the coastal ecosystems on which both wild and farmed fish depend. Addressing these twin problems requires coordinated rather than piecemeal action, with each measure aimed at a distinct point of failure. On the wild-catch side, governments need to enforce catch quotas based on scientific stock assessments, since arbitrary limits are easily circumvented, and to close nursery grounds to trawling during breeding seasons, as New Zealand has attempted with its quota management system, so that juvenile fish are given time to replenish the population. On the farming side, the industry should be steered toward herbivorous species such as tilapia and carp rather than carnivorous ones, since these do not require wild fish meal and so break the cycle of farms depleting the very stocks they exist to substitute; closed containment systems, though costlier to install, prevent disease transfer and pollution far more effectively than open pens. Consumer awareness schemes, including clear labelling of sustainably sourced seafood, can reinforce both measures by shifting demand toward operators that meet these standards. In short, wild stock depletion and the expansion of fish farming are two sides of the same crisis, and neither can be solved in isolation. Only through stricter regulation of ocean fishing combined with more responsible aquaculture practices can seafood supplies be sustained for future generations.

Why this answer earns band 8.5

Task Response: the opening claim that the situation 'is not a simple case of one industry replacing another' avoids a generic restatement and instead commits to treating the two halves as interdependent, which is what separates a band 8.5 introduction from a band 7 one that would simply list both sides.
Task Response: the solutions paragraph earns its density by giving each measure a reason clause ('since arbitrary limits are easily circumvented', 'so that juvenile fish are given time to replenish the population'), which shows development of ideas rather than a bare list of four fixes in one breath.
Coherence and Cohesion: the transitional phrase 'Aquaculture, meanwhile, brings a different cluster of problems' marks the pivot from the wild-stock paragraph to the farming paragraph, keeping the two-part structure visible without resorting to a mechanical 'Firstly... Secondly' sequence.
Lexical Resource: images such as 'strip nearby waters' and 'densely packed pens' carry precise, field-specific connotation, which is stronger evidence of range than a serviceable but ordinary collocation would be.
Grammatical Range and Accuracy: the non-defining relative clause in 'tilapia and carp rather than carnivorous ones, since these do not require wild fish meal' lets a main clause and a qualifying comment sit in one sentence, and the examples of Senegal, Norway, Chile and New Zealand are illustrative details invented to anchor the argument rather than factual claims a student needs to verify.

The plan, reusable on any question of this type

Open by rejecting a one-sided reading of the question and stating that both problems require joint treatment (~58 words)
Group the problems of declining wild stocks by who is affected: coastal livelihoods first, then the wider ecosystem (~94 words)
Group the problems of aquaculture by mechanism: disease and pollution first, then the feed-supply paradox (~99 words)
Match each problem to its own targeted fix rather than offering one blanket solution for both industries (~157 words)
Close by restating that the two problems are linked and must be resolved together (~46 words)

Phrases worth learning

is not a simple case of	to introduce a nuanced argument that rejects an oversimplified view of an issue
extend well beyond	to show that a problem's effects reach further than its most obvious domain
even as it fills the gap left by	to concede a benefit while pointing to a simultaneous drawback
steered toward X rather than Y	to recommend one option over another as part of a proposed solution
neither can be solved in isolation	to conclude that two linked problems must be addressed together

This answer includes invented specific detail written to show how detail is used, not to be quoted as fact: Senegal as the specific named example of a coastal community affected by industrial trawling; Norway and Chile as the specific named locations of the salmon farming example; and New Zealand's quota management system as the specific named example of a fishing regulation policy. IELTS does not check facts, so this is about the texture, never the claim.