Where eagles dare: Annual count shows strong numbers at Lake Tahoe
Special to the Sierra Sun
The crisp air chills the group of bird-watchers as they sit on the pier at Zephyr Cove, on Lake Tahoe’s South Shore, waiting for bald eagles to show themselves.
One of the bird-watchers comes from Sacramento every year to sit on the same pier to count bald eagles with the Tahoe Institute of Natural Science.
Since the 1980’s, groups have gone out once a year to count the number of bald eagles they see within a three hour time period.
About 10 years ago, TINS took over organizing and leading the annual eagle count. On the second Friday of the year from 9 a.m. to noon, volunteers spread out to 26 locations around Lake Tahoe to look for birds. This year, about 90 volunteers came to count.
TINS board member Rich Chambers said it’s important to do it the same time and way each year for more consistent and accurate numbers.
Sarah Hockensmith, Outreach Director at TINS said winter is the best time of year because the eagles migrate down from the Arctic Circle to feed on water fowl.
Bald eagles were listed as a protected species in 1940 but after the introduction of DDT into the environment in 1945, the number of bald eagles started dropping at an alarming rate. DDT caused their eggs to thin, so many eggs broke or never hatched.
DDT was banned in 1972, and the number of bald eagles began rising.
“It’s nice to see how conservation and change in behavior can make an impact,” Hockensmith said.
“Every year is different, and weather conditions, as well as how much snow is in the trees, impacts detection rates, but we have seen a fairly steady, increasing trend since the beginning of the survey at Tahoe (in 1979) up until a few years ago, Hockensmith said.
The 2020 watch saw 24 bald eagles, 17 adults and 7 immatures.
“Since 2014, tallies have usually been in the low 20s, with one year spiking to 27, and last year dipping to 19. As we hover around this recent average, we question if the carrying capacity of Lake Tahoe can provide for ~23 eagles,” Hockensmith said.
Hockensmith also said lately, eagles have been moving down Carson Valley earlier each year to feed on the afterbirdh of cows and scavenge dead calves.
“This may be a result of climate change, but calving season, and the exodus of many of Tahoe’s eagles, has definitely been shifting forward in the calendar year,” Hockensmith said.
During the count, volunteers note when they see the birds, whether they are immature or mature and which direction they’re flying.
Hockensmith then takes the counts from all the locations and puts them on a corresponding map of Tahoe with arrows pointing to the direction they were flying. So if one location notes a mature adult flying to the west and the next location notes a mature adult flying from the east about the same time, Hockensmith can reasonably guess its the same bird.
While getting bald eagle counts is the ultimate goal of the day, its about so much more for the people who come out and do it.
“I like the bird community and socializing but mostly, I like to be outside,” Hockensmith said. “A morning at the lake; you can’t beat that.”
Hockensmith is proud of the bird community TINS has built in the area. During a down moment of the count, she asks volunteers, “If you could be any bird, what would it be?”
She and the volunteers enthusiastically rattle off bird facts, and relive some of their favorite birding moments.
Their passion for birding is contagious and even when there are no eagles in sight, they are genuinely happy to be out there.
However, when there is a bird sighting, the excitement is palpable. Ten minutes before the count was set to end, two adult eagles take to the sky near the Upper Truckee Marsh, with one of them still holding its prey in its talons.
Volunteers from Lake Forest Beach and 64 Acres saw the same two eagles work together as a team to try to get a duck but gave up after fifteen minutes.
“This was a really incredible show of determination by the eagles, and must have cost a great deal of energy,” Hockensmith said.
Hockensmith, who has seen hundreds of eagles, said seeing them never gets old.
TINS hosts regular bird counts including a falcon count in February in Carson Valley.
To learn more, visit http://www.tinsweb.org.
Laney Griffo is a reporter with the Tahoe Daily Tribune, a sister publication to the Sierra Sun. She can be reached at email@example.com