Question 1

Why are invasive species such a problem?

Accepted Answer

Because they arrive **without the predators, parasites and competitors** that constrained them where they evolved, and native species have no evolutionary history of dealing with them.

**What makes a species invasive.** Not simply being non-native — the great majority of introduced species fail to establish, and many that do cause no harm. **Invasive** means established, spreading, and causing ecological or economic damage.

**Why they succeed:**

**Enemy release.** The organisms controlling their numbers at home did not come with them.

**Naive prey.** Native species that never encountered the predator lack appropriate defensive behaviour. This is why island species have been so catastrophically affected — birds evolving without mammalian predators frequently nest on the ground and do not flee.

**Competitive advantage** in the new conditions.

**Rapid reproduction** and generalist requirements, which is why the species that become invasive share recognisable traits.

**The mechanisms of harm:**

**Predation.** Introduced rats, cats, snakes and mongooses have driven a substantial proportion of recorded extinctions, particularly on islands.

**Competition** for food, light or nesting sites — grey squirrels displacing red in Britain.

**Disease transmission.** Grey squirrels also carry squirrelpox, to which they are largely immune and reds are not — so competition and disease compound.

**Habitat alteration**, where the invader changes the physical environment.

**Hybridisation**, genetically swamping a native species.

**The economics.** Invasive species cause enormous costs — in agriculture, infrastructure, forestry and control. **Japanese knotweed** affects property markets; **zebra mussels** block water intakes; **ash dieback** and other introduced pathogens have reshaped landscapes.

**Why control is so hard.** Eradication is only realistic **very early**, and by the time an invasion is noticed it is frequently too late. Islands are the main success stories, because they can be cleared and defended.

**Prevention is the effective intervention** — biosecurity, ballast water regulation, plant passports, and the pet and horticulture trades, which are major introduction pathways.

**Climate change is expanding ranges**, complicating the native/non-native distinction.

Question 2

What is a keystone species?

Accepted Answer

A species whose effect on its ecosystem is disproportionately large relative to its abundance — so removing it causes changes far beyond what its numbers would suggest. The origin. The concept comes

Question 3

How to support wildlife conservation at home?

Accepted Answer

Supporting wildlife conservation at home involves creating a wildlife-friendly garden, reducing pesticide use, and providing habitats. These practices enhance biodiversity and promote healthier ecosystems.

Question 4

What is a marine protected area, and do they work?

Accepted Answer

An area of sea where human activity is restricted for conservation. They work when they are genuinely protected, enforced, and large enough — and a great many are none of those things, which is why

Question 5

How to support local wildlife conservation efforts?

Accepted Answer

You can support local wildlife conservation by volunteering, donating, participating in citizen science, advocating for policies, educating others, and practicing sustainable living.

Question 6

What steps can I take to promote wildlife conservation in my community?

Accepted Answer

Promoting wildlife conservation in your community involves educating residents, volunteering for projects, creating gardens, advocating for sustainability, organizing clean-ups, and engaging with local government.

Question 7

What is biodiversity net gain?

Accepted Answer

A requirement that development must leave biodiversity measurably better than before — in England, a legally mandated minimum uplift, calculated with a defined metric and secured for a long period.

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