The Karner blue butterfly is of particular interest to population ecologists because it is:

1. Population ecologists count individuals to track how a population is doing. 2. Population ecologists are particularly interested in counting the Karner blue butterfly because it is classified as federally endangered. 3. Its distribution and density are highly influenced by the distribution and abundance of wild lupine. 4. So the butterfly's fate is tied to a single host plant. _Source: OpenStax Biology for AP(R) Courses (CC BY 4.0), Ch 35 'Ecology and the Biosphere', sections 35.1-35.5_