Pest-exclusion fence

A pest-exclusion fence is built to exclude certain types of animal pests from an enclosure. This may be to protect plants in horticulture, to preserve grassland for grazing animals, or to protect endemic species in nature reserves.

Animals can be excluded by a fence's height, depth under the ground and mesh size. It is also important to choose a construction material that cannot be climbed; furthermore, sometimes it is necessary to create a subsurface fencing element to prevent burrowing under the fence.

Prior to human settlement New Zealand had no land-based mammals apart from three bat species. The introduced mammal species have since caused huge ecological changes to the biota of New Zealand. Pest-exclusion fences are increasingly used for conservation of indigenous species by excluding all mammals.

Locations of predator-proof fences include:

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