SALT LAKE CITY — A Weber State University Professor has teamed up with the Utah Division of Wildlife Resources to organize a Snowy Plover survey.
From May 15 to June 15, a team of volunteers will work to count Snowy Plovers within survey plots. The goal is to estimate Great Salt Lake’s population.
John Cavitt, a professor of ornithology and the director of Weber State University’s Avian Ecology Laboratory, said the small shorebirds have been in trouble for a while.
“The Pacific Coast population is actually listed as threatened under the Endangered Species Act,” Cavitt said. “And the interior population is … listed under a number of conservation strategies.”
The U.S. Fish and Wildlife Service and the state of Utah list the birds as species of great concern. Great Salt Lake is a critical home for the small birds.
Although researchers know the Pacific Coast Snowy Plover population sits at approximately 2,300 individuals, Cavitt said they don’t know the current interior population. He coordinated an effort on the shores of Great Salt Lake.
A 2008 survey saw 33 volunteers count birds in areas across the lake. They estimated the population to be 5,500 birds.
“It turns out that is the largest known breeding population for the species,” Cavitt said.
This year, that survey will be repeated. When the Great Salt Lake Collaborative spoke with Cavitt, he and the DWR were working to recruit volunteers.
He explained they chose the dates between May and June to coincide with peak breeding season on the lake, ensuring the birds remained in the area.
Volunteers play a critical role in completing the survey, as they’ll be working to count birds within plots.
“We assign people to go to a plot,” Cavitt said, explaining each area is approximately 100 hectares in size.
Participants use a GPS unit to locate their assigned plot. Then, they count each bird they see in the area. Completing one plot usually takes about 2 hours.
“We're also asking them to do some habitat information so we want to know what kind of vegetation is there and how much water and all that kind of thing,” Cavitt said. “We’re hoping to get a couple done at a time.”
The Utah Division of Wildlife Resources will be helping. Cavitt said he hopes the survey team can count on about 300 plots, however, that number could change.
Survey vs. census. What’s the difference?
Cavitt explained the team will be completing a survey. Volunteers will count bird populations on randomly located plots.
In contrast, a census would count every Snowy Plover on the lake. Cavitt said that’s “logistically impossible.”
The plots fall within three levels:
- Known habitats
- Habitats the birds could be in
- Unlikely habitats
“From that we are able to generate an estimate for the population,” said Cavitt.
What makes Great Salt Lake an ideal Snowy Plover habitat?
According to Cavitt, Great Salt Lake’s high saline content provides an environment for the bird species’ unique adaptations.
“They’re using it to its fullest,” Cavitt said.
The National Audubon Society explained that the lake’s fluctuating water levels and diverse habitats provide food sources for the Snowy Plover, which mainly eats insects and small invertebrates, such as brine shrimp. Additionally, their white and grey feathers help them blend into the lake’s playa.
However, the lake’s current condition is hindering the survival of the birds.
“We found in our nesting studies that they don't put their nests anywhere where there's more than 20% of vegetative cover,” Cavitt said. Additionally, they like to be near the water.
He noted that phragmites, which are invasive tall grasses, have encroached on the areas they live in.
“So, when we get these encroachments of phragmites, it just really ruins the habitat for them,” Cavitt said.
