Sika deer were introduced to New Zealand for game hunting in the early 1900s. Their population later increased to hundreds of thousands, causing significant damage to farming and forest ecosystems. They browse on the forest floor and understory vegetation, reducing forest regeneration and affecting ecological succession. Without any known natural predators, their population can grow rapidly.
The model starts with a deer population of 100 and evaluates the relationships between adult deer, young trees, hunter population, food availability, and mast events. Some factors are assumed to remain constant to make the model more manageable and focused.
Excluded factors:
- Disease
- Weather
- Predators
- Migration
- Forestry operations
Assumptions:
- The deer population is represented as a single stock.
- All hunters behave similarly.
- Food availability depends on young trees.
- Hunting pressure increases with hunter numbers.
- Carrying capacity is fixed at 300 deer.
- Mast years increase food availability.
