A treasure to behold in the Swan

Those of us lucky enough to live, work and play in the Swan Valley know what a special place it is. Pointing a finger at exactly what makes this place special, however, can sometimes be difficult. If you were to mill around the Mission Mountains Mercantile on a Saturday and ask tourists and locals alike, "What makes the Swan Valley so unique?" you'd likely hear answers such as "the stunning views," "diversity of wildlife" or "rural character."

While all of this is true, what you likely won't hear is that the Swan is home to one of the rarest aquatic plants in the world. Rare aquatic plants don't normally inspire the same level of excitement from the public as rare charismatic mammals, such as grizzlies and wolverines, but just wait until you hear about water howellia.

Howellia aquatilis, or water howellia, is a member of the Bellflower family (Campanulaceae). It is endemic to the Pacific Northwest, with about two-thirds of known occurrences in Montana. This means that the Swan Valley is home to about 75% of the global population of water howellia.

It's no coincidence that this aquatic annual has an affinity for the wettest watershed in the state. Water howellia depend on vernal pools, which are seasonal wetlands that hold rain and snowmelt in the spring and recede or completely dry up in the late summer or fall. These vernal pools are found within "glacial kettles" or depressions carved into the valley floor by a retreating glacier around 12,000 years ago. This glacial history lends to an uncommon life history.

Water howellia have two types of flowers. The first are "cleistogamous," which means they remain closed and self-pollinate, in this case underwater. The second are "chasmogamous," which are flowers that open and allow for pollination. These white flowers are about half the size of a pencil eraser and bloom at the water's surface in mid-July.

The resulting seeds from both types of flowers germinate once the pool dries up and they are exposed to the air and variable fall temperatures. These germinated seeds then overwinter underneath the snow and wait for the pools to fill with water the following spring. The number of plants in a particular wetland is determined by how much the pool dried out the previous year, as seeds cannot germinate under water.

Due to this highly specific habitat association and threats of wetland degradation, water howellia was listed as a threatened species in 1994 under the Endangered Species Act (ESA). After nearly two decades of wetland conservation, the U.S. Fish and Wildlife Service (USFWS) removed water howellia from the ESA on June 16, 2021. Upon delisting, USFWS must work cooperatively with Montana (and other states where water howellia is found) to monitor the aquatic plant for at least five years to ensure the species is self-sustaining.

To achieve this, the Montana Natural Heritage Program (MTNHP) and the U.S Forest Service (USFS) Flathead National Forest (FNF) put together a proposed monitoring program. In this proposal, MTNHP and the FNF will survey at least 30 water howellia ponds for two consecutive years to establish baseline population information. If approved, the monitoring will take place in the summer and fall of 2022 and 2023. Survey data collected will include water howellia abundance, water depth, photo points and ambient temperature.

In addition to MTNHP and FNF staff, Swan Valley Connections (SVC) will join these surveys, along with a group of tribal high school students from the Mission Valley known as the Mission Mountains Youth Crew. This youth crew is designed to expose high schoolers to careers in natural and cultural resource conservation through stewardship, and is supported by the National Forest Foundation, Salish Kootenai College, the FNF and SVC. Through this collaborative monitoring project, we hope to increase awareness about this unique plant and celebrate the little things that make our valley one-of-a-kind.