Quantitative review of state imperiled species acts
This study was recently published in Conservation Letters, which you can read here. Below see interactive maps of our findings.
Abstract:
To combat biodiversity loss in the United States, imperiled species are protected under the federal Endangered Species Act (ESA), which is currently threatenedby political initiatives seeking to weaken it and potentially transfer substantial authority to the states. To assess the conservation capacity of current state laws, we conducted a quantitative analysis of imperiled species protection within all 50 states by compiling data on all state-listed species, ESA-listed species, and IUCN Red List species in each state. We found that currently 16% of ESA-listed speciesand 52% of IUCN imperiled species are not protected by any state law, and if the ESA were repealed these numbers could increase to 73% of ESA-listed species and 81% of IUCN imperiled species unprotected. Although protection varies widely among states, our results suggest that revoking the ESA would be highly detrimental to imperiled species conservation and recovery in the United States
State Listed Species
The total number of species protected in each U.S. state by each state imperiled species act:
(Hover over or click on each state to see the total value)
Now let’s split this into animal and plant species protected in each state
Total animal species protected in each state
Total plant species protected in each state
After we collected data on all the protected species in each state, we also collected data on all of the IUCN imperiled species (i.e., species categorized as Critically Endangered, Endangered, or Vulnerable) and all of the federally listed species (protected by the Endangered Species Act) that occur in each state
Total IUCN imperiled species in each state
Here I’ve split the map into quantiles instead of using a continuous scale for better visualization due to outliers (i.e., Hawaii). You can hover over the state to see the extact number of IUCN imperiled species
Total federally listed species in each state
This is the total number of species listed on the Endangered Species Act that are found in each state. Again these values are split into quantiles due to outliers (mainly Hawaii) for better visualization.
I then assessed state-level coverage of the IUCN and ESA lists by calculating the proportion of IUCN imperiled species and proportion of ESA listed species that occur in each state that are also protected by that state
Percent of IUCN imperiled species protected in each state
Percent of ESA listed species protected by each state imperiled species act:
All maps made with the leaflet and fiftystater packages
