Nature Notebook, August 13, 2020


Catch the end of this year’s late-night Perseid meteor shower in the eastern sky through Aug. 24. A new moon rises Tuesday, Aug. 18 and brings some morning low tides just before sunrise.

A thin layer of late summer dust coats many plants along the trails as the warm season closes out. I’ve been hearing the tap-tap of woodpeckers, mostly acorn woodpeckers over Olema marsh and around the wetlands. Woodpeckers have an extra backward-facing toe to help them grip trees as they pound holes for nesting cavities and food storage. The acorn woodpeckers live in colonies and construct granary trees, filled with dozens of drilled holes, placing hazelnuts and acorns into the holes. As the nuts dry and shrink, the birds move them to different holes, returning to feed on nutmeats and insects.

The tule elk rut has begun at Tomales Point and should last through October. An alpha or dominant male will vigilantly watch over a group of females—its “harem”—to claim breeding access and usually allows a few secondary or beta males to aid him. The alpha may be seen wrestling with antlers and making bugling sounds. The plant material hanging from their antlers is part of a strategy to attract mates: They urinate on themselves and then roll in the brush.