Biology Regents Practice Exam

What impact does the hemlock wooly adelgid have on its ecosystem?

1. It increases biodiversity in New York State forests

2. It provides food for native bird species

3. It can carry diseases that can be spread to pets

4. It disrupts habitats that native species depend upon

The correct answer is: It disrupts habitats that native species depend upon

The hemlock woolly adelgid is an invasive pest that poses significant ecological threats, particularly to hemlock trees, which are a crucial component of northeastern forests in the United States. When these trees are infested, they can experience severe stress or even death as a result of the adelgid's feeding habits. This decline in hemlocks has a cascading effect on the ecosystem. Hemlock trees play a vital role in maintaining the structure of the forest, providing shade, stabilizing soil, and influencing water quality and temperature in nearby streams. As hemlocks die off, the habitats they create become disrupted, leading to a loss of shelter and food sources for various native species, including birds and mammals that depend on these trees for their survival. The decline in hemlock populations can also impact undergrowth and soil organisms, ultimately reducing overall biodiversity in the area. Therefore, the correct answer highlights how this pest disrupts habitats critical to the survival of numerous native species, leading to a decline in ecosystem health.