What criteria should one use in categorising a species as threatened ?

Explanation

To categorize a species as threatened, one should consider the following criteria:

1. **Population Decline**: The first criterion is the observation of a decreasing population trend. If the number of individuals in a species is declining year after year, it indicates that the species may be at risk of extinction. This decline can be due to various factors such as habitat destruction, pollution, overexploitation, or climate change.

2. **Habitat Loss and Fragmentation**: The second criterion involves assessing the species' habitat. If there is significant habitat loss or fragmentation, it can lead to a decrease in the population of that species. Habitat loss can occur due to urban development, agriculture, deforestation, and other human activities. Fragmentation can isolate populations, making it difficult for them to breed and survive.

3. **Predator Pressure**: The third criterion is related to the pressure from predators. If a species is under constant threat from predators, whether natural or human-induced (such as hunting), it can significantly increase the risk of extinction. High levels of predation can lead to population declines, especially if the species has a low reproductive rate or is already vulnerable due to other factors.

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