Wildlife & Conservation Vocabulary in English

An endangered species is one that faces a very high risk of extinction in the wild. The IUCN Red List classifies species by threat level, with ‘endangered’ being two steps from extinction — the categories are: Least Concern, Near Threatened, Vulnerable, Endangered, Critically Endangered, Extinct in the Wild, and Extinct. Species become endangered due to habitat loss, poaching, pollution, climate change, or invasive species reducing their populations to critical levels. Examples of currently endangered species include the Amur leopard, the black rhino, and the Sumatran orangutan.

A habitat is the specific physical environment where a particular species lives — for example, a rainforest, a coral reef, or a freshwater pond. An ecosystem is a broader system that includes all the living organisms in an area together with the non-living elements (water, soil, climate) and the interactions between them. One ecosystem can contain many different habitats. For instance, the Amazon ecosystem encompasses river habitats, forest floor habitats, canopy habitats, and more — each home to different, specialised species.

Poaching is the illegal hunting, capturing, or killing of wild animals, often for commercial gain. Animals are poached for their tusks (elephants), horns (rhinoceroses), skins (big cats), or to be sold as exotic pets. Poaching is a major driver of species decline and is illegal under international conventions such as CITES (the Convention on International Trade in Endangered Species) as well as national laws. It is distinct from legal, regulated hunting or fishing conducted under licence within set quotas.

Biodiversity refers to the variety of life on Earth — the diversity of species, genetic variation within species, and the range of ecosystems. High biodiversity makes ecosystems more resilient: they can better withstand disease, climate fluctuations, and human impacts because different species play different functional roles. Biodiversity loss weakens ecosystems and threatens the services humans depend on, including clean water, pollination of crops, soil fertility, climate regulation, and stable food supplies. Scientists often describe biodiversity as the foundation of all human life on Earth.

Conservation involves the sustainable management and use of natural resources to protect them for future generations — it allows some human activity within controlled limits, such as regulated fishing or managed forestry. Preservation aims to keep natural areas and species entirely untouched and free from human interference, as in a nature reserve closed to the public. In practice, most environmental policy blends both approaches: some areas are strictly preserved while others are managed sustainably to allow human use without long-term damage.

An invasive species is a plant or animal introduced to an environment where it did not evolve naturally, either accidentally or deliberately by humans. Without natural predators or competitors, invasive species can multiply rapidly, outcompeting native species for food, space, and breeding sites, causing serious ecological and sometimes economic damage. Classic examples include grey squirrels displacing red squirrels in the UK, cane toads devastating wildlife in Australia, and Japanese knotweed damaging buildings and riverbanks across Europe.

A wildlife corridor is a strip of protected or managed habitat connecting two or more larger patches of natural land. As human development fragments natural landscapes with roads, farms, and cities, corridors allow animals to move safely between areas, find mates, access food sources, and follow seasonal migration routes. They are a key tool in modern conservation planning. Examples include underpasses and overpasses built beneath or over motorways, and riparian corridors of vegetation along riverbanks linking isolated woodland patches.

Yes, very much so. Environment and wildlife topics appear extremely frequently in IELTS Reading and Writing sections. Task 2 essay prompts regularly ask about animal extinction, deforestation, human impact on biodiversity, and environmental responsibility. Knowing precise vocabulary — such as habitat fragmentation, biodiversity, keystone species, and ecosystem services — significantly improves your Lexical Resource score. IELTS examiners reward candidates who use topic-specific vocabulary accurately and avoid repeating vague terms like “animals” or “nature”.

A predator is an animal that hunts and kills other animals for food. The animal that is hunted is called prey. The relationship between predator and prey is fundamental to healthy ecosystems: predators control prey populations, preventing overgrazing of vegetation and maintaining ecological balance. Without apex predators, prey species multiply excessively and can devastate plant communities. Wolves, lions, sharks, and eagles are classic apex predators. Removing them — as happened when wolves were extirpated from Yellowstone — can trigger dramatic and often unexpected changes throughout the entire ecosystem.

At B1 level, prioritise: habitat, species, predator, prey, migration, conservation, endangered, and sanctuary. These appear constantly in nature documentaries, news articles, and exam texts. At B2, add: biodiversity, ecosystem, poaching, deforestation, invasive species, wildlife corridor, keystone species, reforestation, pollination, and habitat fragmentation. Watching BBC nature documentaries with English subtitles is an excellent way to hear all of these words used naturally by expert communicators.