East Bay Hills/Western Diablo Range

A Coastal Roach (Hesperoleucus venustus) was observed in Berkeley on October 2, 2026. This threatened native cyprinid continues to inhabit freshwater creeks in the ecosystem despite its declining range, with repeated observations in the Berkeley area over recent months.

A Red Speckled Dun mayfly (Callibaetis ferrugineus) was recorded at Tilden Regional Park on October 17. Mayfly larvae in Callibaetis are pollution-sensitive aquatic insects requiring clean, well-oxygenated water, indicating that some creeks in the ecosystem still support suitable conditions for these taxa.

Red Swamp Crayfish (Procambarus clarkii) were recorded in Oakland on October 21 and Signal Crayfish (Pacifastacus leniusculus) in Berkeley on October 16. Both invasive species compete with native fauna and disrupt stream ecosystems, reflecting their established presence in local freshwater habitats.

Water at the NOAA tidal station stood 0.338 meters above the predicted astronomical tide on October 22 at 15:06. This positive surge indicates wind-driven or pressure-driven water piling up in the estuary today.

Western Toad was recorded on 2026-10-17 at Shell Ridge Open Space in Walnut Creek and in Alamo. The species is federally Threatened and uses ephemeral and seasonal pools for breeding; fall emergence into upland habitat for foraging and dispersal precedes the wet season migration to breeding sites.

California Newt was photographed on 2026-10-18 at Kennedy Grove Regional Recreation Area in El Sobrante. The species is federally Threatened; late October marks the onset of the annual migration from upland refuges to vernal pools and creeks for winter breeding and egg-laying.

Monarch butterflies were recorded 6 times in October (most recent 2026-10-21) across Alameda County and the region, including at Broadmoor District and Yerba Buena. The species is federally Proposed Threatened; mid-to-late October is peak movement as monarchs migrate southward to overwintering sites in Mexico.

Sulphur-bellied Flycatcher was confirmed by eBird reviewers at Golden Gate Park on October 14 with 518 separate reports. This species breeds in Mexico and winters in the eastern Andes and is a vagrant on the Pacific coast, appearing only during fall migration events when birds are displaced from their normal range.

Fine particulate air quality is forecast to rise to AQI 55 (Moderate) on September 21-22, driven by the Chileno Fire which started today in Marin County with 341 acres burned and 45% of its perimeter contained. Smoke from distant fires can degrade air quality locally even at 39 miles; residents sensitive to particulates should monitor forecasts closely over the next few days.

Speckled Dun mayflies (Callibaetis pictus) were recorded six times across the East Bay and San Francisco since early April, most recently in Moraga on September 13. These small mayflies of family Baetidae are found in Central America and North America and are pollution-sensitive aquatic insects requiring clean, well-oxygenated water, indicating that some streams in the ecosystem still support conditions suitable for sensitive taxa.