08/13/2026
In honor of today being , hereās an update on Californias oldest known wolf pack, the Lassen Pack.
The Lassen Pack which produced its first litter in 2017, had at least 4 pups born this year. The breeding female this year is again LAS09F, a gray wolf who was born to the Lassen Packs original breeding pair herself in 2018. The breeding male this year is again LAS16M, who dispersed to California from outside the state and joined the Lassen Pack in June 2019. LAS16M, who was formally a black wolf, is now almost silver in color as heās aged. He is also the oldest known wolf in California currently, and he and LAS09F have reproduced litters together consecutively since 2020.
The Lassen Pack currently has 8 wolves (the breeding pair, two additional adults/yearlings and 4 pups). So far as well, they have not been implicated in no known confirmed wolf predations on livestock in 2026. You may have read in the news recently about the Lassen Pack regarding the recent UC Davis study released of their diet consisting largely cattle. The aim in addressing this point is to give additional context on the Lassen Pack.
The study which occurred during the summer months of 2022 and 2023, could not differentiate from the s**t samples they collected if it was from cattle the wolves actually killed or cattle the wolves were scavenging. Summer 2022 followed several months after the 2021 Dixie Fire ravaged through the Lassen Pack territory, which was the 2nd largest wildfire in California history. During the summer of 2022, the Lassen Pack used a different summer range which was perhaps due to local deer distribution changes resulting from the Dixie Fire, and were scavenging off of cattle in predation investigations released that summer. We shared several of those examples of the Lassen Pack wolves observed scavenging cattle, with the cause of deaths of the cattle confirmed to NOT be wolf from predations.
https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=202855&inline
https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=203102&inline
https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=203104&inline
The following year in summer 2023, the samples showed a smaller consumption of meat from cows. Cattle showed up in 55% of f***l samples accounted for 50% of their diet. The Lassen Pack that year was more consistently consuming natural prey sources such as deer. That is not to say there hasnāt been confirmed documentation of chronic predation from wolves in California on livestock, such as with the former Beyem Seyo Pack last year. But the Lassen Pack generally speaking rarely has been known to predate on livestock.
Photo is of members of the Lassen Pack taken by Morgan Heim in 2020, this post was written by John Marchwick.
Sources
https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=202877&inline
https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=247120
https://amp.sacbee.com/news/local/article316361614.html