Study by Central and UConn scientists reveals genetic divides in rare mink populations

- Mink may look the same, but according to new research published in the April 20 issue of Heredity, a mink in the Florida Everglades is a world away from its cousins in the northern part of the state.

Researchers from the University of Connecticut (UConn) and Central Connecticut State University (Central) have utilized modern genomic analysis that may very well settle a long-standing debate over the taxonomic status of the state-listed threatened Everglades mink (Neogale vison evergladensis). Their findings also reveal that mink in the southeastern United States possess significant genetic differences driven by the unique environmental pressures ranging from seasonal flooding to shifting salinity.

Cracking the genetic code

Despite being widespread across North America, mink populations at the southern edge of their range in Florida have long been a mystery to conservationists. Previous studies relied on limited genetic data, but this new project marks a massive leap forward.

Led by UConn evolutionary biologist Elizabeth Jockusch, computational genomicist Jill Wegrzyn, and Rachel O’Neill, director of the Institute for Systems Genomics, the team developed the first-ever pangenome for the Mustelidae family (which includes weasels, otters, and ferrets). By sequencing every nucleotide from six different minks across three subspecies, the researchers were able to pinpoint exactly which genes were missing or altered in each population.

Survival of the most adaptable

The study confirmed three distinct subspecies, each with genetic signatures tailored to their specific Florida habitats:
•    The Everglades Mink (N. v. everglandensis): These animals showed genetic differences in reproduction and sensory systems, likely an adaptation to the Everglades' seasonal flooding. Most alarmingly, the study revealed extreme inbreeding levels—surpassing those of critically endangered species like the black rhinoceros and western lowland gorillas.
•    The Gulf Coast Mink (N. v. vulgivaga): Found in coastal marsh, these mink showed adaptations related to oxidative stress, likely a result of living in environments with constantly shifting salinity.
•    The Atlantic Coast Mink (N. v. lutensis): This northeastern Florida population inhabits tidal estuaries and showed enrichment in genes for neurological development, similar to traits found in highly intelligent semi-aquatic mammals like sea otters and dolphins.

"This study supports the value of natural history collections for conservation genomics," says Wegrzyn.

Central Connecticut State University conservation biologist Paul Hapeman’s lab has been studying mink in Florida for more than a decade in collaboration with Florida Fish and Wildlife Conservation Commission using a variety of approaches including camera surveys and genetic analysis. Hapeman provided the team with samples and archived specimens from the Florida Museum of Natural History.

A new model for training scientists

The research was powered by UConn’s NSF-funded RaMP (Research and Mentoring for Post baccalaureates) program. Eleven postbaccalaureate fellows shared co-first authorship on the paper, gaining high-level skills in computational genomics.

"The approach of using genomic data to assess subspecies classifications has tremendous potential to assist with status assessments and eventual protections," says Paul Hapeman.

For many of the fellows, the project was transformative. “I experienced first-hand how instrumental genomics can be for conservation policy,” says Airianna McGuire, a RaMP fellow and current UConn doctoral student. “I was inspired by the power of pangenomics and will now be constructing a pangenome for [the migratory fish species] Arctic grayling as part of my doctoral work.”

Bridging the gap

Until now, the primary reference genome for minks was based on individuals from the UK, likely descended from escaped farm animals. The UConn/Central study found that the UK reference mink carried genetic changes related to immunity—an adaptation to the overcrowding and disease pressures of fur farms—which differs significantly from wild North American populations.

By providing these new genetic resources, the researchers have given wildlife agencies a powerful new toolkit to protect and manage Florida’s unique and vulnerable mink populations.

About the research

This work was supported by National Science Foundation award DBI-2217100. The paper, published in Heredity, features co-first authorship by RaMP trainees Aishatu Affini, Hailey Baranowski, Scott Forbes, Elena N. Foust, Kristyn Hatley, Ethan L. Ni, Airianna McGuire, Kyle Paist, Mary Rutter, Robin N. Smith, and Nataly Vargas.