In the Footsteps of Fishers

Building on work from Washington's National Park Fund, the National Park Foundation is supporting a comprehensive three-year study exploring how reintroduced fishers are surviving in Mount Rainier and North Cascades National Parks and beyond.

The study monitors their population dynamics, behaviors, and survival post-reintroduction, hoping to contribute to broader conservation strategies focused on preserving their habitat and ensuring the fisher’s long-term viability in the region

Leading these efforts is Ransom, a wildlife biologist with the National Park Service at North Cascades National Park. His work is crucial to understanding whether the reintroduced fishers are thriving and establishing self-sustaining populations. This study not only aims to safeguard the success of past efforts but also offers a blueprint for future reintroductions, reinforcing the resilience of both the species and its habitat.

So why fishers, and why now — "it wasn’t too big of a question,” Ransom says.

“The North Cascades is especially fortunate because we’ve maintained almost the full suite of biodiversity that existed pre-colonization, and fishers are a big missing piece of the puzzle." He underscores the opportunity for reintroduction, stating, "The habitat and food are all still here. We’re just missing fishers."

Considering the broader significance of biodiversity, Ransom says, "When we consider all the uncertainty ahead of us — climate change, what’s going to happen, how things are going to change — the one thing we know is that the more species there are, the more resilient an ecosystem is. Adding fishers back in was kind of a no-brainer; they were an important missing piece in the puzzle."

The Study

The fisher, once hunted nearly to extinction for its fur, now relies on that same fur to secure its future. Following their reintroduction to the parks, researchers have been using advanced techniques to monitor these creatures, with fur playing a crucial role in understanding their success in the wild.

Initially, each released fisher was fitted with Very High Frequency transmitters, requiring researchers to get close with an antenna — a challenging and labor-intensive process. However, many fishers remained undetected, possibly due to the animals hiding in rugged terrain where radio signals couldn’t penetrate.

“They see the world in a way we don’t,” Ransom said. “It’s hard to imagine navigating that kind of landscape and distance as a small animal.”

So, the team turned to state-of-the-art camera stations equipped with hair snags. These stations capture fur samples, which can be genotyped to identify individual fishers and assess genetic diversity. The same fur that once marked them as targets now helps scientists monitor their survival and adaptation.

The primary goal of these surveys is to determine whether fishers are persisting long-term and to understand their distribution across the ecosystem.

“What we’re looking at now with these surveys is, are they distributed across the entire ecosystem? Do we have reproduction? And hopefully we’ll get viable genetics from these stations that will tell us exactly who visited the camera station,” Ransom explained.

So far, the study has yielded promising results, particularly in Mount Rainier, where fisher detections exceeded expectations. Hair samples collected at stations during the winter of 2022-2023 detected at least three fishers that were not original founders, indicating fishers are reproducing on their own. Additionally, the research has highlighted dietary differences between fishers in the north and south regions, which could impact survival and reproductive success.

Uniting Communities

The study efforts have also been characterized by strong community collaboration and outreach initiatives. This phase of the project, focused on monitoring and understanding the impact of reintroduction, underscores the critical role of local communities and indigenous tribes in wildlife conservation. From the outset, the project was designed not only for scientific research but also as a platform for education and community engagement.

"This was a cool project from the start because it was just so perfect for education and outreach. We had kids release almost every fisher; we had school groups come out, we had groups from different tribes and First Nations participate," said Ransom.

Fishers hold both ecological and cultural significance, serving as a valuable natural resource that indigenous peoples, like the Nisqually Indian Tribe, historically honored by using fisher fur in their regalia. The involvement of indigenous tribes in the reintroduction project has been essential, intertwining ecological stewardship with cultural revitalization. Ceremonies marking the fishers' return to ancestral lands have not only symbolized the species' reintroduction but also exemplified a collaborative effort that bridges conservation science with cultural heritage.

Monitoring the success of the fisher reintroduction has also been a landscape-scale community effort. As part of this study, four federal and state agencies, six tribes, various non-government organizations, and volunteers all helped deploy over 260 monitoring stations across the Washington Cascades.

Scrappy Survivors

The final season of field work wrapped up in summer of 2024, and now park scientists are conducting a comprehensive analysis of the gathered data, encompassing genetics, camera detections, and habitat distribution. This holistic approach aims to paint a vivid picture of the landscape and assess the success of the fisher reintroduction efforts.

The team's immediate focus lies in deciphering crucial indicators such as evidence of reproduction and measures of genetic diversity among the fisher population. These metrics will serve as vital signposts, guiding decisions on future interventions and management strategies. Regular intervals of assessment are envisioned to ensure ongoing vigilance and adaptation in response to emerging trends or concerns.

However, the journey doesn't end with the initial findings or the mere presence of fishers in their restored habitats. It's a dynamic process that demands long-term commitment and resilience. Ransom emphasizes the importance of achieving a sustainable population — a critical mass — that can thrive independently in the wild. Looking forward, the project's success hinges on continued monitoring and adaptive management.

Throughout the study, as more data is analyzed and insights are revealed, one word consistently defines the fishers: resilience. Ransom describes the small mammals as survivors.

"If we just give them a chance, they're scrappy. They'll survive. Like many wildlife species, if we can just give them space and a chance to live their lives, they can reclaim their place in the ecosystem we all share," Ransom says.

This resilience shines through despite the numerous challenges posed by human activities such as road crossings and exposure to toxins. As park scientists start to reflect on the findings and the ongoing efforts to understand and protect these animals, the story of the fishers underscores an important lesson in resilience — a testament to their value in the ecological landscape of Washington and a call to action to ensure their continued survival and flourishing.