Only an estimated 20,000 Mission blue butterflies exist in the world — and they’re all found near San Francisco
The Bay Area is made up of 10,191 square miles — an area comprised of lofty skyscrapers, sea-level marshes, and an estimated 500-plus species of wildlife. (That’s not even counting our region’s native flora.) Needless to say that we, truly, do live within an urban jungle… that exists right outside the walls of our expensive domiciles.
That fauna, however, is in peril. Or more specifically: a growing number of Bay Area animal species continue inching closer to extinction.
From what’s considered the country’s “most beautiful serpent” to a mouse weighing no more than a half-ounce, here are fifteen Bay Area animal species at risk of going the way of the dodo bird — by and large because of human development and the climate crisis.
Each and every one of these species could use our help to keep them from the brink; do your individual part, which may include supporting a local nonprofit spearheading Bay Area conservation efforts, to ensure these creatures are still around for future generations.
- Southern sea otter (Enhydra lutris nereis): Threatened; biggest threats include ocean pollution, marine vessel activity, and warming seas that threaten their food supplies
- Guadalupe fur seal (Arctocephalus townsendi): Threatened; biggest threats include warming oceans disrupting migratory breeding habits, waning food availability, and marine activity.
- Salt-marsh harvest mouse (Reithrodontomys raviventris) Endangered; biggest threats include human development, the draining of endemic marshlands, and invasive species — like European rats and feral cats — either preying on them or vying for food resources.
- Rainbow trout (Oncorhynchus mykiss): Threatened; biggest threats include human development and the climate crisis leaving fertilized eggs more vulnerable and less likely to hatch due to water acidification.
- Tidewater goby (Eucyclogobius newberryi): Endangered; biggest threats include salt marsh and lagoon draining — which is the only habitat the tidewater goby can thrive in — and pesticide runoff affecting the benthic invertebrates and local insects it survives off of.
- Coho salmon (Oncorhynchus kisutch): Endangered; human development — especially regarding dam construction — and habitat loss remain the biggest threat to the species.
- California least tern (Sterna antillarum browni): Endangered; biggest threats include a reduction of the small fish species they prey on and destruction of the coastline habitats where they mate and raise young.
- Least bell’s vireo (Vireo bellii pusillus): Endangered; single biggest threat over the past three decades continues to be a loss of riparian habitats — the only ecosystems the birds can breed in successfully.
- Northern spotted owl (Strix occidentalis caurina): Threatened; biggest threats include rodenticides poisoning their food supply, urban light pollution altering their nocturnal habits, and human development.
Reptiles and Amphibians
- California red-legged frog (Rana draytonii): Threatened; biggest threats include droughts worsened by the climate crisis, human development, and feral cats and other invasive species preying on them.
- San Francisco garter snake (Thamnophis sirtalis tetrataenia): Endangered: biggest threats include human development, a reduction in available prey from the competition with invasive species, and the climate crisis altering mating patterns.
- Alameda whipsnake, also known as the Alameda striped racer (Coluber lateralis euryxanthus): Threatened; biggest threats included the use of rodenticides poisoning their prey, vehicle traffic activity, and human development.
Insects and Invertebrates
- Black abalone (Haliotis cracherodii): Endangered; biggest threats include warming and acidifying oceans, illegal marine vessel activity… and now landslides.
- San Bruno elfin butterfly (Callophrys mossii bayensis): Endangered; biggest threats include urban air pollution, a decline in wildflower densities, invasive mite species, and both herbicides and pesticides
- Mission blue butterfly (Icaricia icarioides missionensis): Endangered; biggest threats to human development, herbicides and pesticides, and a reduction in the only three lupine species their larvae will feed on.
Feature image: The San Francisco garter snake is not only one of the most prepossessing reptiles in the world, but it’s also one of the rarest; as few as 1,000 examples of the species might be left in the wild. (Photo: Mason Cummings/Parks Conservancy)