NORTHERN NEW MEXICO
How warmer winters are affecting the Carson National Forest
Elk, cutthroat trout patterns are changing
VALLE VIDAL 鈥 When Pennzoil Co. donated 100,000 acres of pristine grasslands and high-mountain waterways in the heart of the Sangre de Cristo Mountains to the public in 1981, it was 鈥 for many northern New Mexicans 鈥 like being handed the keys to a paradise.
Francisco 鈥淜iko鈥 Cortez was 11 years old when his dad took him fishing along the Rio Costilla on the west side of the basin in the mid-鈥80s, after residents in the area had rediscovered a swath of wilderness
Standing at the river鈥檚 edge on a foggy fall morning, Cortez remembers hearing elk calls echoing off the hillsides, through the surrounding conifers and quaking aspens that hem in this high-mountain basin, which is home to one of the state鈥檚 largest elk herds.
鈥淵ou could hear this eerie sound coming through the fog,鈥 Cortez said. 鈥淲e used to like camping up there during that time and hearing them all night long. You鈥檇 hear them running by your camp at night, almost running over your tent. Some people would complain that those 鈥榙ang elk鈥 would keep them up all night, but I loved that.鈥
After graduating from Taos High School, Cortez turned his passion for the wilds of northern New Mexico into a 36-year career as a wildlife biologist for the Forest Service, from which he retired last year.
A fisherman crosses the Rio Castillo, in July 2023. The river is in the Carson National Forest鈥檚 Valle Vidal. National Forest employees in New Mexico are not sure yet if they will get their jobs back after a Merit Board ruling Wednesday.
His duties included strategizing annual closures in the Valle Vidal designed to protect the basin鈥檚 2,000-some elk, which have traditionally migrated to lower-elevation grazing lands on the east side of the valley in winter and returned west to higher elevation areas for summer calving season.
But Cortez said those closures 鈥 held from May 1 to July 1 to the west and Jan. 1 to April 1 to the east, respectively 鈥 may no longer suit these animals鈥 regional grazing patterns as dry, warm winters become longer and more frequent.
鈥淏ecause of climate change, or whatever you want to call it 鈥 why it鈥檚 not snowing 鈥 that may cause the management agencies to think about this differently now,鈥 he said.
Typically, elk in the Valle Vidal seek to conserve energy and find more accessible forage on the east side of the basin in winter, while returning west to birth calves in summer.
More recently, Cortez said these large ungulates are remaining at higher-elevation areas longer due to a lack of snowfall 鈥 a pattern now seen for two consecutive winters in New Mexico.
Studies support Cortez鈥檚 observations that migratory patterns for elk, as well as other species, are shifting due to climate change.
published in the journal Global Change Biology, found that Yellowstone鈥檚 herd of roughly 20,000 elk were also arriving an average of 50 days later on wintering ranges in 2015 than in 2001, confirming reports by rangers and park visitors.
found that half of all species worldwide 鈥 from squirrels to moose to mountain lions 鈥 are seeking refuge in higher-elevation areas due to .
Cortez also helped spearhead a restoration project for Rio Grande cutthroat trout, a high-elevation, cold-water fish
鈥淭hat project started with just the Valle Vidal, but then it expanded to the Vermejo and all the other entities,鈥 he said. 鈥淚t was a career project for me.鈥
Cortez said he began noticing diminishing numbers of Rio Grande cutthroat trout while performing stream habitat surveys in Valle Vidal as a Forest Service technician in 1989, when he first joined the Carson.
Alongside the New Mexico Department of Wildlife, Carson National Forest and other researchers, they identified stressors caused by both climate change and invasive fish, which they relocated as they reintroduced cutthroat trout into the waters that run through the basin.
鈥淚t was just the start of getting baseline habitat conditions and where we maybe needed to improve some habitat and follow up with a greater restoration effort,鈥 he said.
While the Rio Grande cutthroat trout remains an at-risk species, it has stayed off the endangered species list in part due to their efforts and , according to the Department of Wildlife.
Cortez said it鈥檚 the kind of proactive, adaptive work that can preserve wildlife 鈥 and the wilderness areas where they dwell 鈥 for future generations.
Now a grandfather, he said he hopes to take his kids鈥 kids to the Valle Vidal to show them the wonder of the high-mountain basin that captivated him as a child.
鈥淭he big part of that is I could show them, not just there but across the forest, what I worked on,鈥 he said. 鈥淭hat鈥檚 important to me.
鈥淚 had the opportunity to go elsewhere in my career, for advancement to see a different part of the world, but I never wanted to,鈥 he added. 鈥淭his was always my ranch, my Valle Vidal. Why would I want to go somewhere else, where my grandkids may not be able to see what we did?鈥
John Miller is the 近距离内射合集鈥檚 northern New Mexico correspondent. He can be reached at jmiller@abqjournal.com.