Nature Notebook, December 17, 2019


Winter technically begins with the solstice, the shortest day of the year, on Monday, Dec. 21. It is the season of extreme tides, with 6-plus-foot tides rolling in over the New Year’s week with corresponding low tides late in the afternoons. The solstice also brings an amazing sky: the conjunction of two planets, Jupiter and Saturn, that will appear as a single brilliant star at around 7 p.m. in the western sky. The Ursid meteor shower will peak on the same evening; if you are up after midnight, look for the meteors near Ursa Minor, or the Little Dipper.

The first reports have come in of the return of coho salmon for the winter spawning season in Lagunitas Creek, with state park rangers reporting a few at the Leo T. Cronin viewing area. A few Northern elephant seals are returning to the outer beaches of the Headlands and Drakes Beach. Any day now, the first southbound gray whale may be spotted.

One thing about rain and damp mornings is the softened earth, which allows us to see animal tracks much more easily. The v-shaped hoof prints of black-tailed deer are perhaps the simplest to identify. If you see claws on the prints, it is mostly likely a canine, such as a coyote or fox. No claws usually indicate a cat species, such as a bobcat; most cats have retractable claws that they extend for climbing and withdraw for normal walking.