The National Park Service has asked that a lawsuit over feral horses at Cumberland Island National Seashore be dismissed/NPS file

The fate of feral horses at Cumberland Island National Seashore is in the hands of a federal judge who must decide whether the National Park Service's hands-off approach to the horses and their impacts is justified.

A lawsuit filed against the Park Service earlier this year argued that the feral horses not only are damaging the seashore's environment and two federally protected species but are not being humanely managed and should be removed from the seashore.

But in asking that the lawsuit be dismissed, the federal agency, represented by the Justice Department, says it has not waived its sovereign immunity from being sued, but that the plaintiffs have failed to show that the Park Service failed to take an action that it was required to take.

The lawsuit also claimed that the horses were adversely impacting critical habitat for loggerhead sea turtles, an endangered species, and interferring with nesting females, trampling hatchlings and eggs, and also impacting critical habitat for the piping plover, another protected species, and so the Park Service's failure to remove the horses is a violation of the Endangered Species Act.

However, the Park Service replied [response attached below] that there was no evidence that its staff at the national seashore had impacted the two species and that it was "unaware of any cases in which a court has held that a federal agency is liable for a take of one animal perpetrated by another..."

At the same time, the agency acknowledged back in 2018 that the horses were having adverse impacts on the seashore's natural resources.

Studies of horse impacts at CUIS have found that grazing activity, including vegetation consumption and trampling, significantly reduces vegetative cover, growth, and reproduction in these habitats (Turner 1986, Dolan 2002). Grazing also appears to be altering plant species composition and is likely increasing the vulnerability of dunes and salt marshes to erosion and storm damage (Turner 1986, Dolan 2002). In addition to impacts on vegetation, feral horses compact wetland soils, altering soil properties (e.g., infiltration rates) and disturbing vital soil-dwelling organisms (Noon and Martin 2004). The wastes produced by horses contribute to nutrient enrichment or eutrophication of wetlands and waterbodies, and can contaminate waters with pathogens, including E. coli bacteria (Noon and Martin 2004). Together, these impacts make wetland habitats less favorable for native plants, fish, herpetofauna, and invertebrates. 

The plaintiffs in the lawsuit — Georgia Equine Rescue League Ltd., the Georgia Horse Council Inc., Center for Biological Diversity Southeast Director Will Harlan, Cumberland Island resident Carol Ruckdeschel, and even the horses themselves — counter that the Park Service has a responsibility not to allow the horses to range freely across the national seashore and "has a mandatory, non-discretionary duty to protect the natural resources, wildlife, and wilderness of the Seashore by prohibiting feral horses as free ranging livestock from having access to the Seashore."

They also note that the Park Service in the 1980s removed free-roaming cattle from the national seashore, and recently received $760,000 through the Biden administration's Inflation Reduction Act to remove feral pigs from the seashore. Allowing feral horses to remain, and continue to impact seashore resources, runs contrary to the Park Service's mandates to protect natural resources and conserve ESA species, the groups maintain.

"Defendants' 50 years of bureaucratic inertia and non-feasance cannot justify their ignoring the statutes, rules, and regulations designed to protect the Cumberland Island National Seashore," the plaintiffs said in arguing against dismissal [attached below] of the matter.