# Explain how the ecological niche concept can be used to predict the likely impact of removing a top predator from an ecosystem.

> IB DP Biology Higher Level (2023 syllabus) — B4.2 Ecological niches · Explain · 4 marks

## Mark scheme (4 marks)

1. A top predator occupies a niche that involves regulating the population size / abundance of prey species below it in the food web.
2. Without the top predator, prey species can expand their realised niche / population, potentially exceeding the carrying capacity of shared resources.
3. Mesopredators / competing species previously suppressed by the top predator may also expand their niches, intensifying competition with other species (mesopredator release).
4. This cascading alteration of niches (trophic cascade) can reduce biodiversity / restructure community composition, demonstrating that niches are interdependent and dynamically linked within an ecosystem.

## Key terms

- [ecological niche](https://www.gradenine.co.uk/glossary/ecological-niche)
- [top predator](https://www.gradenine.co.uk/glossary/top-predator)

## Related

- [Revision notes for IB DP Biology Higher Level (2023 syllabus)](https://www.gradenine.co.uk/learn)
- [How to answer "Explain" questions](https://www.gradenine.co.uk/tools/command-word-cheatsheet)
- [Practice this with AI marking (free)](https://www.gradenine.co.uk/start)

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Source: [GradeNine](https://www.gradenine.co.uk/q/explain-how-the-ecological-niche-concept-bc608192) · Published by Druglandscape Ltd.