Guest author Karan Gathani is a certified Grassroots Ecology California Naturalist, and writes about the San Francisco Bay and Delta Biogregion for California Biodiversity Week 2021. You can follow more of Karan's writings posted on California Naturalist Diaries.

What things do you love about your bioregion?

I live in the San Francisco Bay Area/Delta Bioregion which means there is more to life than just paying Jacksons for your Avocado Toasts and artisan brewed coffee. For starters, it is one of the few bioregions on the Pacific coast where you can spend the morning tide pooling, get humbled while hiking through a redwood forest during the afternoon and still be on time to watch the sunset from the top of a mountain on the same day. And since the weather is usually cooperative for such outings, one can go exploring all year-round.

What are the highlights in terms of wildlife, geology, watersheds, beloved cultural resources, iconic species, etc?

San Francisco Bay is among the largest estuaries on the Pacific coast. This makes it an invaluable rest stop along the Pacific flyway. Hence, every winter you will see all the tidal wetlands swarmed with thousands of migrating shorebirds and waterfowl. The scene is reminiscent of the town of Indio taken over by selfie-obsessed kids during the annual Coachella Valley festival and then abandoned at the end of the festival.

Another fascinating thing about this area is the presence of North American beavers residing inside a popular neighborhood park in the South Bay Area. Trying to convince people that a beaver is residing in the creek 50 ft from where people are walking and biking makes them wonder if I believe in unicorns as well.

A North American Beaver at a popular neighborhood park in South Bay

What natural phenomena do you look forward to annually?

There are so many things that I look forward to at different times of the year, but I will be mindful of the people reading this and list just one, which is not fair, but so is life.

San Jose being one of the largest and most populated cities in the United States has a remarkable event occurring every year in its Guadalupe River. The Chinook Salmon make their journey back swimming upstream from the Pacific Ocean to the place they were born. It is a sight I wish every resident gets to experience when the exhausted Salmon is using its last ounce of energy to power through the obstacles in hopes of passing along its genes. They die soon after mating and spawning. It is one event that makes you appreciate the struggle for life, the tragedy of death and joy of birth all in one landscape. It is a sober reminder to why it is so important to keep our watersheds clean and healthy, if we ever want to sustain a healthy Salmon population for future generations.

A Chinook Salmon swimming upstream in the Guadalupe River

Favorite guides and/or local naturalists that helped you to learn more about the bioregion

I owe a debt of gratitude to all the naturalists I get the opportunity to share the space with and constantly learn about new things. Among those, Dr. Merav Vonshak, Jan Hintermeister and Colter Cook are some people who have influenced me in looking holistically at the ecosystem rather than concentrating on a few species.

Activities you love to do to explore the unique nature of your bioregion

I try to participate in every local BioBlitz, and lucky for me that BioBlitz.club and Keep Coyote Creek Beautiful organize one every month. Other than that, exploring with docents by going on bird walks organized by San Francisco Bay Bird Observatory and Santa Clara Valley Audubon Society. And finally, explore a different world by going on night hikes with Grassroots Ecology and MidPeninsula Regional Open Space Preserve docents.

 September 4-12, 2021 is California Biodiversity Week. Join us in celebrating the unique biodiversity and renewing our commitment to stewarding the state's incredible natural heritage! During the Week, CalNat is posting blogs authored by members of our community, ending in our September 14th CONES event from noon-1:00 PM. Be sure to also check out a list of activities and resources online from the CA Natural Resources Agency!

Roxanne Moger shares a post, "Heading out at dawn for a day of nature observations on the first day of the City Nature Challenge. #calnatshare"

The City Nature Challenge encourages people to explore their urban nature, connect with local advocacy organizations and other iNaturalist users, and learn how to participate in community biodiversity science. From its first competition between the San Francisco Bay Area and Los Angeles County in 2016, it quickly has grown to include more than 350 cities around the world. The search for nature over a period of 4 days each spring inspires over 50,000 people to tune in to the nature in their backyards thousands of miles apart.

Within California, a global biodiversity hotspot, we encourage certified naturalists and stewards to use the iNaturalist skills gained in the program to safely participate. Using our growing UC California Naturalist Certified Naturalists project, which certified naturalists can join, we are able to better track the contributions of individual naturalists. Once a certified naturalists joins the project, observations made in California over all time are counted (email Sarah Angulo, sangulo@ucanr.edu with questions). An amazing 10,500+ species have been documented by certified naturalists who have so far joined the project, who make up just a fraction of the 4,000 certified to date. Naturalists are making a huge contribution to science through these observations.

California had 7 cities participate in the City Nature Challenge 2021: the Bay Area, Los Angeles County, San Diego County, Sacramento Region, Orange County, Inland Empire, and Mendocino County. Certified California Naturalists contributed to the over 93,000 total observations made in the 7 cities. Of these 93,000+ observations made in the state, California Naturalists in the top 20 observers for each city contributed 12%! Within the top 20 users,

San Francisco Bay Area: Emily Gottlieb (PRNSA) #1, Sarah-Mae Nelson (UC ANR) #4, and Leslie Flint (Audubon Canyon Ranch) #7 made 5% of their city's total observations.

Los Angeles County: Laura Schare (Catalina Island Conservancy) #1, Amy Jaecker-Jones (Dominguez Rancho Adobe Museum) #8, Kat Halsey (Pasadena City College) #11, and Ron Matsumoto (Dominguez Rancho Adobe Museum) #17 made 9% of their city's total observations.

San Diego County: Susan Heller (Preserve Calavera) #6, Millie Basden (Preserve Calavera) #7, and Karen Merrill (Preserve Calavera) #17 made 7% of their city's observations.

Sacramento Region: Lauren Glevanik (UC Davis) #2, Cliff Hawley (Effie Yeaw Nature Center) #3, Hailey Adler (UC Davis) #4, Mary Hanson (Tuleyome) #5, Laci Gerhart (UC Davis) #6, Sarah Angulo (Sierra Streams Institute/UCANR) #8, Roxanne Moger (Tuleyome) #12, Charlie Russell (Tuleyome) #15, Linda Estes (Effie Yeaw Nature Center) #17, and Sabine Angulo (American River Conservancy) #21 made 35% of their city's observations.

Orange County: James Bailey (Catalina Island Conservancy) #3, Noelleellowski (Catalina Island Conservancy) #10, Emily Chebul #13 (Pasadena City College) made 9% of their city's observations.

Inland Empire: Colin Barrows (UC Riverside Palm Desert) #1, Joye Cantrell (UCR Palm Desert) #5, Susan Forgrave (UCR Palm Desert) #6, Sendy Hernandez Orellana (UCR Palm Desert) #7, Elizabeth Ogren Erickson (UCR Palm Desert) #12 made 24% of their city's observations.

Mendocino County: Asa Spade (Hopland REC) #1, Brook Gamble (UCANR) #2, Shane Hanofee (Sierra Streams Institute) #3, Lori Dudzik (Hopland REC) #4, and Hannah Bird (Hopland REC) #14 made 42% of their city's observations.

The impact of our naturalists is even greater than just the few who are in the top 20 observers for their city. Even for naturalists who contributed one observation or identification this year, every documentation of our state's unique biodiversity is important. Thank you for each one of you who took a moment to contribute this year, especially given the difficulties we each face. 

Sierra Tiger Beetle by Cliff Hawley

American Robin by Sarah-Mae Nelson

Blainville's Horned Lizard by Sendy Hernandez Orellana

San Diego Monkeyflower by Karen Merrill

A "Natural History Note" From UC California Naturalist's lead scientist, Dr. Cameron Barrows.

In nature, species are constantly “striving” to be “better” species. To be clear, this is not a conscious effort, rather that improvement can occur through reproduction, there are new combinations of genes being created with every generation, both through mutations and through the mixing of genes through sexual reproduction. For asexual species, gene mutations are the avenue for change; for species capable of sexual reproduction, there is both mutation and the unique gene combinations of the two parents. Change (evolution) for asexual species is slow.  Change for sexual species is much faster. The arbiter of whether a mutation and/or a unique gene combination is “better”, more successful at surviving and ultimately reproducing themselves, is the environment, and the environment is always changing. Slowly or quickly, change is happening. Now, through climate change and the introduction of invasive species, we are often the catalysts of change. Before we arrived on the scene climates still changed (but more slowly), and new species did show up and disrupt the status quo, and once in a great while an asteroid slammed into the earth. Change has always been a feature of nature, and the species that make up the nature we all love are there because they were “better” than their predecessors at surviving and reproducing in today's environment. Tomorrow's environments will be different.

The creosote bush’s strategy is longevity. They can live for hundreds and in some cases thousands of years, in part because nothing eats them (enough) to kill them.

Creosote bush is successful by any measure. They have become one of, if not the, most numerous species in each of the Chihuahua, Sonora, and Mojave Deserts. I can think of a handful of plant species that straddle two of those deserts, but only Creosote bushes thrive in all three. Over the eons they have evolved, via mutation and unique gene combination, a cocktail of chemicals in their tissues that repel over-browsing by rabbits and pronghorn antelope and tortoises and desert iguanas and chuckwallas. That same cocktail appears to repel damaging bacteria and possibly viruses, and so has the potential to benefit human health as our disease vectors develop immunities to the antibiotics we use today. But you might object, what about the 60 or so insects that are specifically associated with creosote bushes, what about the 14 species of creosote gall midges that lay their eggs in the plant's tissue to create abnormal growths for their larvae to eat and be protected from parasites? The answer is that none of those pesky bugs kills or reduces the reproductive potential of their creosote bush hosts. That which does not kill them makes them stronger.

The creosote bush's strategy is longevity. They can live for hundreds and in some cases thousands of years, in part because nothing eats them (enough) to kill them. During their long lives there will be many droughts and many wetter periods. Only occasionally will the conditions be right for long enough to allow for successful reproduction. “Young” creosote bushes are rare compared to the densities of their parents. If you live for centuries you do not have to be successful at reproduction very often, and the cost of producing flowers, fruits, and seeds almost every year is not enough to subtract from their longevity. So far, in our analyses of how species are responding to the levels of climate change we are currently experiencing, creosote bushes seem to be shrugging their leafy shoulders.

Desert tortoises do not live centuries, but they might live as long as we humans do.

If longevity is good, then perhaps desert tortoises are also adapted to surviving climate change. Desert tortoises do not live centuries, but they might live as long as we humans do, which is much longer than most wildlife species. Through their lives they too will experience droughts and wetter periods. Like creosote bushes, there are increasingly rare combinations of wet years that foster survivorship in the vulnerable hatchling tortoises. Not being able to predict the future any better than we can, except for in the driest years, female tortoises will lay a clutch of eggs in most years, hedging their bets that the eggs will hatch into a wet weather cycle. If it is a wet spring with lots of food, the females may lay larger clutches and sometimes multiple clutches, all depending on the health and condition of the females. Unlike creosote bushes, there is a considerable cost to the female tortoises for each clutch they lay. If conditions are dry and there is little or nothing for the tortoises to eat for multiple years, there can be a terrible cost in terms of the females' body condition, health, and survivorship. Dr. Jefferey Lovich has been studying desert tortoises for decades. In recent years he has found high tortoise mortality in some populations, and when examining the dead tortoise shells, he has found that the vast majority of dead tortoises were females. Those areas with high female mortality have been hit particularly hard by increasing aridity born by modern climate change.

At the opposite end of the longevity spectrum are side-blotched lizards, which typically live for one, or more rarely two years.

At the opposite end of the longevity spectrum are side-blotched lizards, which typically live for one, or more rarely two years, especially in our hot deserts. Dry year or wet, they need to breed and produce viable young within a year, or at most two years, or their population is kaput. What we are finding is that this lizard's preferred habitat, as evidenced by where we find them at the highest densities, is shifting to higher elevations. There are still some at lower elevations, but those are usually in or near desert washes where rainwater can be concentrated, and so conditions are not quite as arid as those in the open desert. Or they occur in appropriately landscaped suburban yards where conditions are also less arid (if cats or the high concentration of roadrunners do not eat them). Otherwise, side-blotched lizard populations are moving up in elevation. Those living at higher elevations reproduce better than those at the lower elevations, so that upper elevation edge is expanding while the lowest elevation edge is incrementally contracting. In dry years that shift is clear; in wetter years there is a bit of a reprieve and the lower edge lizards do ok. Every year is different, but the overall trend is pushing these lizards, along with other species, up in elevation.

Long-term observations are essential to discover these patterns. A community of naturalists that help collect these data at multiple locations across gradients of aridity, are equally essential.

Nullius in verba

Go outside, tip your hat to a chuckwalla (and a cactus), and be safe.