Which of the following describes an occasional pest?

An occasional pest is characterized by its sporadic presence and the conditions that allow it to become problematic. This can result from specific life cycles, such as breeding patterns that coincide with certain times of the year or environmental influences, like weather changes that affect its population. These pests do not consistently pose a threat, but their population can surge under favorable conditions, making them an issue for crops at certain times.

The other options describe different pest dynamics. A major threat refers to pests that are persistent and consistently harmful across various environments. Pests that are consistently present in most environments are often considered endemic, while having a limited distribution to specific climates aligns with pests that are localized rather than occasional. Thus, by understanding the behavior and characteristics of occasional pests, one can better manage and mitigate their impact on agricultural practices.