“What is the long-term trend of official snowfall at your park? Have changes impacted your operations or the lake itself?” – Murray Bolesta, from Facebook.
The latest installment of “Ask The Ranger” had us touching base with our Natural Resources team.
Average annual snowfall has, on average, been decreasing over the last several decades. Back in the 1930s, Crater Lake received an average annual snowfall of 614 inches (51.2 feet). The 2010s annual average, 80 years later, had dropped by 34% to 404 inches (33.7 feet).
We asked long-time Lake Researcher Scott Girdner if he and his staff have noticed any Lake changes that might be tied to reduced snow levels.
“It is hard to identify impacts with so much year-to-year variability in snowfall…(so) we don’t have any specific known impacts from the decreasing snowfall.”
On land, however, decreased snowfall (and corresponding increased rainfall averages) appear to be affecting animal and plant communities:
- New animal species are appearing in the Park (e.g., raccoons);
- Longer grazing time in the Park for deer and elk, who can find food here a little longer;
- Heavier animals who avoid late fall / early spring high elevation snow (e.g., coyotes, wolves) can now come up to higher elevation for longer periods, creating more competition for food with lighter species who would typically dominate those areas (e.g, Sierra Nevada red fox, bobcats, pine martens);
- Increased spring rains, followed by cold weather and snow, can wreak havoc on nesting birds, decreasing nesting success;
- Increased (earlier) growing season that might lead to mismatched pollinator/bloom relationships;
- Multiple blooming/seeding cycles per year in some non-native plants, benefitting weeds; and
- A lengthened fire season, with more opportunity for high-intensity fire behavior (drier fuels).
Good question, Murray! Fortunately, on land and the lake, researchers have been monitoring ecological variables for decades, and we have the means of identifying many environmental changes by looking at the Park’s long-term monitoring data.