Biodiversity is the number and variety of organisms found within a specified geographic region.
New Zealand’s native biodiversity is unique because of our long isolation as small islands in a vast ocean. The high percentage of species found nowhere else in the world makes New Zealand’s native biodiversity both special and highly vulnerable.
New Zealand was one of the last places on earth to be settled by humans, but it has one of the worst records of native biodiversity loss. Fire, land clearance, over-exploitation of resources and introduced plants and animals have had cumulative and damaging impacts on native biodiversity. As a result, dozens of species have become extinct, and an increasing number are threatened with extinction.
Nature of science
We can start to understand socio-scientific issues, such as deforestation, overfishing and resource exploitation, by gathering relevant scientific information in order to draw evidence-based conclusions. This will allow us to take informed action where appropriate.
Direct species loss
Hunting led to the extinction of a quarter of our land-based birds, including the moa. When the first humans arrived in New Zealand, they found a rich bounty of plants and animals. Over time, over-consumption of many important food sources led Māori communities to develop customs and practices to prevent the depletion of a valuable resource. An example of this is rāhui – a restriction placed on food collection in an area. Today, the harvest of native species is strictly controlled and monitored.
Loss of habitat has been extensive since the arrival of humans. Trees have been felled for timber, forests burned to create farmland and wetlands drained to create pasture. A great importance has been placed on preventing any further habitat loss, and much is being done to restore forest, wetland, stream margin and coastal habitats.
Pests and weeds
Unwanted animals and plants have been brought to New Zealand by both settlers and visitors – sometimes intentionally (for example, rabbits) and sometimes accidentally (for example, didymo). Biosecurity measures are in place to try and prevent the arrival of any unwelcome pests.