Alaska’s unforgiving climate once kept invasive species at bay.
Katherine Schake, of the Homer Soil and Water Conservation District, said that isn’t the case anymore.
“We are seeing shifts in our climate and temperatures don’t get as cold for as consistent an amount of time, which means insects don’t get killed off in the winter like they used to," she said. "With our peatlands drying on the Kenai Peninsula, those are less acidic soils. The ecosystem is shifting around quite a bit. And it makes the habitat more vulnerable to certain invasive species.”
Last week was one of two annual National Invasive Species Awareness Weeks, a chance to learn about the weeds and creatures infesting local ecosystems.
For people like Schake, managing invasive species is a year-round effort. It’s also an effort in flux.
A bill moving through the Alaska House would create a formal council and dedicated response fund for managing invasive species statewide. The bill was introduced last year but was put on the backburner when COVID-19 hit.
Separately, a peninsula-based organization historically focused on invasive plants is now formally broadening its scope to include invasive animal species. Now, it’s the Kenai Peninsula Cooperative Invasive Species Management Area, or CISMA. Schake is the coordinator for CISMA.
Maura Schumacher is a CISMA field coordinator and the invasive species specialist for the Kenai Watershed Forum.
“Invasive species do not recognize borders," she said. "They don’t care who owns the land. So it only makes sense for all of us to be working together and to establish the same goals.”
CISMA is coordinated by soil and water conservation districts but brings in other partners, including the Chugach National Forest, Department of Natural Resources and private landowners. Previously, the Kenai Peninsula Borough has helped purchase herbicide and the Kenai Watershed Forum has contributed equipment and personnel. Partners also keep a shared database of new infestations.
That cooperation is partly why broadening the scope of CISMA made sense.
“The same agencies and organizations that are working on these plant infestations are also dealing with animals and other taxa of invasive species," Schumacher said.
Not all non-native species are invasive. Invasive species have to also cause harm, like the elodea plant, which alters salmon habitats. Some economists think unmanaged elodea infestations could damage commercial sockeye fisheries to the tune of $160 million a year.
Invasive species managers on the peninsula also worry about northern pike, which were illegally stocked in local rivers and streams and can wreak havoc on other fish populations.
Schake said detecting invasive species early is more cost effective than eradicating them once they’ve already taken hold. The good thing about Alaska, she said, is managers are forewarned about what might happen up here based on how species are taking hold in the Lower 48.
“And I think European green crab is a good example of that, where it started on the Eastern seaboard and just decimated shellfish populations that a lot of the local economies depended on up and down the East Coast," she said. "Then it was introduced on the West Coast and we’re watching it, because there are community monitoring stations as it creeps up northward through British Columbia. Now it’s near Metlakatla, in Southeast Alaska."
She said they're keeping watch for the arrival of the invasive crab locally.
The Alaska Department of Fish and Game asks for Alaskans to report sightings of the species on its watch list. You can report those sightings through the department’s website.