MAMMALS  |  The Sierra Nevada has the greatest chipmunk diversity on the planet. The greater Tahoe region has five different species, though they are very difficult to tell apart, and, making it even harder, they occasionally hybridize. All of our chipmunks are easily discernible from the similar golden-mantled ground squirrel, whose stripes do not extend to its face.

MAMMALS  |  Beavers are native to the Sierra Nevada and provide important eco-system services. They were trapped out of the region long ago, leading early biologists to believe they were singularly absent from the range. However, radiocarbon dating of ancient dams and other lines of evidence prove they have long been part of the native fauna.

BIRDS  |  315 species of birds have been documented in the Lake Tahoe basin. Many are rare visitors, including scissor-tailed flycatchers, a lesser black-backed gull that returned multiple times from Iceland, a western sandpiper that had been banded in Siberia, and Arctic terns that migrate annually from pole to pole. Check out tahoebigyear.org to learn more!

BIRDS  |  Peregrine falcons breed at Tahoe. Not only that, they have been increasing in numbers at a steady pace in recent years. This is great news for a species that was on the federal list of threatened and endangered species until 1999. TINS is helping to monitor seven active pairs in the Lake Tahoe area.

BIRDS  |  American white pelicans that breed at Pyramid Lake regularly travel through Truckee to forage in the Sacramento River delta. The round trip takes about a week, largely following the I-80 corridor. Many visit Martis Creek Reservoir, Glenshire Pond, and other shallow bodies of water along the way as adults seek easier fishing to provide for their growing young on Anaho Island in Pyramid Lake.

INVERTEBRATES  |  Our area has a long and important history of butterfly study. The first commercial butterfly farm in the U.S. was started by the McGlashan family in Truckee in 1911, and ground-breaking ecological studies on butterflies have continued at Donner Summit from the 1960s through today. Joining TINS’ butterfly count in July is a great way to start learning about Tahoe’s 100-plus species, such as the western pine elfin.

INVERTEBRATES  |  Tahoe is home to black widow spiders. They can be found along the Nevada side of the Basin, as well as in Olympic Heights and Glenshire. What we do not have, however, are brown recluse and hobo spiders. There are literally hundreds of similar-looking brown spiders in the Sierra, requiring careful examination of the eyes, genitals, and other features to correctly identify them.

INVERTEBRATES  |  The longest beetle in North America can be found here. The largest specimens of the western pine sawyer (aka ponderous borer) can reach 65 mm in length. Adults emerge in mid-summer and are regularly seen during July and August, and their larvae feed on dead or recently fallen Jeffrey and ponderosa pines.

PLANTS  |  The Tahoe region has 10 species of orchids. One of the rarest is the phantom orchid. This small, white ghost is found only during moist years in low-elevation forests from Homewood to Cascade Lake. Try the Emerald Bay Campground in late June, as this will be a good year to look for them.

PLANTS  |  Eight species of pine tree grow here. The Washoe pine was not described to science until 1945, having been first found in 1938 in the Galena Creek drainage. Its taxonomy is still under debate, but its cones are quite different from both Jeffrey and ponderosa pines, its closest relatives. Why mature trees of all three of these species emit vanilla or butterscotch fragrance remains a mystery.

PLANTS  |  Local aspen are under attack. The most widely distributed North American tree species, aspen are extremely important for wildlife in the Sierra Nevada. In the last few years, white satin moths, an exotic pest from Europe, have invaded aspen stands on the Nevada side of the lake, threatening the health and longevity of these trees and the rich ecological communities that inhabit them.