This October 24-26th I was in Anchorage, Alaska for the 18th annual Alaska Invasive Species Workshop. The workshop is organized by the Committee for Noxious and Invasive Pests Management and University of Alaska Fairbanks Cooperative Extension. It is a chance for people involved in invasive species management in Alaska – or just interested in the topic – to learn about the latest science, policies, and management efforts within the state and beyond. I am not an Alaska resident – nor had I ever been there until this trip – but my sister lives there, and I was planning a trip to visit her and her family, so why not stop in to see what’s happening with invasive species while I’m at it?
What follows are a few highlights from each of the three days.
The theme of the workshop was “The Legacy of Biological Invasions.” Ecosystems are shaped by biotic and abiotic events that occurred in the past, both recent and distant. This is their legacy. Events that take place in the present can alter ecosystem legacies. Invasive species, as one speaker said in the introduction, can “break the legacy locks of an ecosystem,” changing population dynamics of native species and altering ecosystem functions for the foreseeable future. Alaska is one of the few places on earth that is relatively pristine, with comparably little human disturbance and few introduced species. Since they are at an early stage in the invasion curve for most things, Alaska is in a unique position to eradicate or contain many invasive species and prevent future introductions. Coming together to address invasive species issues and protect ecosystem legacies will be part of the human legacy in Alaska.
The keynote address was delivered by Jamie Reaser, Executive Director of the National Invasive Species Council and author of several books. She spoke about the Arctic and its vulnerability to invasive species due to increased human activity, climate change, and scant research. To address this and other issues in the Arctic, the Arctic Council put together the Arctic Biodiversity Assessment, and out of that came the Arctic Invasive Alien Species Strategy and Action Plan. Reaser shared some thoughts about how government agencies and conservation groups can come together to share information and how they can work with commercial industries to address the threat of invasive species. She stressed that Alaska can and should play a leadership role in these efforts.
Later, Reaser gave a presentation about the National Invasive Species Council, including its formation and some of the work that it is currently doing. She emphasized that invasive species are a “people issue” – in that the actions and decisions we make both create the problem and address the problem – and by working together “we can do this.”
Most of the morning was spent discussing Elodea, Alaska’s first invasive, submerged, freshwater, aquatic plant. While it has likely been in the state for a while, it was only recognized as a problem within the last decade. It is a popular aquarium plant that has been carelessly dumped into lakes and streams. It grows quickly and tolerates very cold temperatures, photosynthesizing under ice and snow. It propagates vegetatively and is spread to new sites by attaching itself to boats and float planes. Its dense growth can crowd out native vegetation and threaten fish habitat, as well as make navigating by boat difficult and landing float planes dangerous. Detailed reports were given about how organizations across the state have been monitoring and managing Elodea populations, including updates on how treatments have worked so far and what is being planned for the future. A bioeconomic risk analysis conducted by Tobias Schwörer was a featured topic of discussion.
After lunch I took a short break from the conference to walk around downtown Anchorage, so I missed a series of talks about environmental DNA. I returned in time to hear an interesting talk about bird vetch (Vicia cracca). Introduced to Alaska as a forage crop, bird vetch has become a problematic weed on farms, orchards, and gardens as well as in natural areas. It is a perennial vine that grows quickly, produces copious seeds, and spreads rhizomatously. Researchers at University of Alaska Fairbanks found that compared to five native legume species, bird vetch produced twice the amount of biomass in the presence of both native and non-native soil microbes, suggesting that bird vetch is superior when it comes to nitrogen fixation. Further investigation found that, using only native nitrogen-fixing bacteria, bird vetch produced significantly more root nodules than a native legume species, indicating that it is highly effective at forming relationships with native soil microbes. Additional studies found that the ability of bird vetch to climb up other plants, thereby gaining access to more sunlight and smothering host plants, contributed to its success as an invasive plant.
Seed pods of bird vetch (Vicia cracca) in Fairbanks, Alaska
The final day of the workshop was a veritable cornucopia of topics, including risk assessments for invasive species, profiles of new invasive species, updates on invasive species control projects, discussions about early detection and rapid response (EDRR), and talks about citizen science and community involvement. My head was swimming with impressions and questions. Clearly there are no easy answers when it comes to invasive species, and like other complex, global issues (made more challenging as more players are involved), the increasingly deep well of issues and concerns to resolve is not likely to ever run dry.
Future posts will dig further into some of the discussions that were had on day three. For now, here are a few resources that I gathered throughout the workshop: