Fig 1.
Species status at time of listing, 1985–1991 versus 1992–2020.
(A) Comparison of population size at time of listing for plants and animals. There are no significant differences between the two periods (Wilcox Test values of p = 0.08, p = 0.41, and p = 0.66, for plants, vertebrates and invertebrates respectively). (B) Comparison of number of populations at time of listing. There are no significant differences between the two periods for plants and invertebrates. Values of zero indicate species for which there were either no known individuals or no known populations at time of listing. Median values shown above each plot.
Fig 2.
Trends in number of species protected under the ESA and funding for species management, 1985–2020.
(A) Change in cumulative number of ESA listings compared to change in Resource Management Appropriations. The lower timeline illustrates political control of the Presidency and, by a majority, each house of Congress. (B) Number of species delisted for various reasons.