by Nora Kehoe
Sitting on the shore of Lower McDonald Creek, sun beating on our faces, and a cool breeze blowing off the fast-running water, I see movement in the rapids. A dark head with a signifying white dot on its face appears. I immediately radio, “Lancaster 181, I think I see one.” Prior to that morning, I hardly knew what a Harlequin Duck looked like.
A volunteer was unable to attend the three-day Harlequin Duck eDNA survey and, on a whim, I was invited by wildlife technician Holli Holmes to help on her graduate project. I met Holli through my bird conservation internship at Glacier National Park’s MAPS station under Lisa Bate. We are lucky enough to have a bird banding station in collaboration with the MAPS (Monitoring Avian Productivity and Survivorship) program, which is a continent-wide collaboration to promote the conservation of our beloved avian species. I grew close to the team at the MAPS station and twas ecstatic to continue working with them. I woke up at 5 a.m. to leave my home in Bigfork, meeting my team at the park. Lisa, Holli, and Barb Lancaster, an experienced volunteer, gave me a rundown on protocols and showed me pictures of Harlequins.
On the first day, we performed a ground survey using team observations. My partner is Barb, a stranger to me, who soon became a close friend. We leapfrogged along the two-mile stretch of creek, ensuring a pair of eyes was on the water at all times. Just a short time before our excursion, major flooding erupted in Montana. Harlequin ducks nest within feet of fast-moving water, so the flooding could have easily destroyed any nests. Although chances of seeing Harlequins was lowered because of this, the team did not give up hope.
The Latin name for the Harlequin Duck, Histrionicus histrionicus, is derived from pantomime plays featuring dramatic dress and makeup. The dramatic coloring is shown in the male ducks, or drakes, with chestnut-colored splotches on their sides, and an overall slate blue color. They have striking white and black stripes across their body. Female Harlequins have allover smooth gray plumage. Harlequins are commonly identified by a white crescent in front of their eye and a white dot on the neck.
Harlequin Ducks are unique among waterfowl with highly evolved adaptations to their environment. These sea ducks are a complex species, spending the summer breeding season in subalpine rapid streams and rivers in the extent of their breeding habitat, Northwest Montana. Female Harlequins make their nest along the rocky shores of rapid mountain streams each year returning to their natal waters. Harlequins form long-term pairs during winter months on East and West coastlines. Due to their harsh habitat many Harlequins have been found with bone fractures. Their diet consists of aquatic insects, small fish, and small invertebrates.
With two days left of the survey, we set out again, this time to locate game cameras along the water. Barb and I follow a map, which leads us to climb down to the water’s edge in order to change memory cards in six game cameras. Again, we are lucky enough to observe a female duck foraging in the rapids.
The third and final day was the most influential for me, I was able to be a part of new technology, never used before for Harlequin surveys. Environmental DNA or eDNA, is organismal DNA in water which is able to be filtered out by a specialized surveying process. This DNA could be from feces, skin cells, feathers, etc. Depending on conditions, the DNA can remain in the water for 7-21 days allowing the Harlequin DNA to be detected in many places. On the lower portion of Upper McDonald Creek, we took 15 samples along the two mile stretch of water. The team was very encouraging, and I was able to take a majority of the samples, using equipment and data collection. I was so grateful to have an entire team so supportive of me.
After the three-day survey I was definitely exhausted but felt so accomplished. Working with these amazing biologists was absolutely incredible. Over three days we were lucky enough to see a pair of female Harlequins. I was able to learn so much about them, watching their fascinating movements through the water.
With the help of Lisa Bate, and others along the way, Holli Holmes’ project overall is studying non-invasive research techniques, specifically, ground-based surveys, camera traps, and eDNA water samples. This will help determine the future for Harlequin studies, allowing scientists to analyze changes to things such as population declines or breeding habits. Her findings will be presented in March.
https://www.allaboutbirds.org/guide/Harlequin_Duck/lifehistory
https://www.audubon.org/field-guide/bird/harlequin-duck
https://www.usgs.gov/special-topics/water-science-school/science/environmental-dna-edna
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