Island Ecology

White flowers of the Blackthorn bush

Photograph of a Blackthorn bush in flower.

White flowers of the Blackthorn bush

White flowers of the Blackthorn bush

Photograph of a Blackthorn bush in flower.

Enlarge image

The first thing that makes Ireland different is the fact that we’re an island. In fact, because Britain is between us and mainland Europe, we’re an island in the Atlantic Ocean that’s off the shore of another island. The biodiversity of islands is always different to the biodiversity of continents. One of the main differences is that islands don’t have as many species because many plants and animals find it hard to get to them in the first place. Most birds can fly so it’s easier for them. But some birds don’t like flying over wide stretches of water, so many of them never make it to islands either.

As an example, we only have about thirty native tree species in Ireland. There are around sixty in Britain and well over a hundred in continental Europe. It’s hard to give precise numbers because there are still arguments about whether or not some trees are native, and more arguments about whether some of the smaller species, for example blackthorn, are trees or shrubs.

There are many more examples like this, some of them on the next page.