A Natural History of the Golden State

byJeffrey A. Hart, Ph.D.

Greetings,

A Natural History of the Golden State is both a wide-angled and a focused look at California’s nature. Its’ central purpose is to bring the joy and intellectual excitement of California nature to the general public, nature enthusiasts, environmental consultants,

students, and fellow scientists. The goal is to rekindle delight that may be lost amid today’s environmental concerns and political differences regarding the role of nature and resources in modern civilization and economy. Perhaps akin to the journeys of earlier naturalists, such of those of William Brewer, Clarence King and John Muir, this trek is an exploration of a more innocent relationship to nature in California. Our region is a magnificent place to appreciate and learn about nature. Several broad topics integrate the understanding of California nature; these include geography and the role of environment, the inherent biological makeup of particular groups of organisms, and the place of evolutionary history. Unlike other regions of the world, such as the

tropics or the East Coast of the United States where the environment is filled with competing species, plants and animals in the open, arid and fluctuating environments of California survive by adapting to the constantly changing physical conditions. The

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unique physical environment provides a backdrop for the evolution and ecology of many forms of endemic species in the Golden State. While many species in California are newly evolved to this environment, others are older evolutionary relics. California’s plants and animals make up a cast of characters that uniquely interact with the physical and biological world befitting an organism’s inherent nature and history. To that end, we explore the histories and biological connections of California’s life of plants, fish, reptiles, birds, and mammals in six, two hour lectures. Like personalities in a Dickens novel, the different taxonomic characters are biological personalities with unique histories and behaviors. First, here’s something about the instructor:

ABOUT THE INSTRUCTOR: Jeff Hart’s early childhood was spent along the Sacramento River in Northern California where his family owned a fishing resort and raised livestock. This early life was one where rural impressions fashioned his world views, of bucolic scenes of agriculture and nature, fishing and tending livestock, of dogs and long walks, and of developing a kinship with Native Americans. This boyhood experience led to the University of Montana, earning degrees in environmental biology and ethnobotany. This was a fun and rewarding time of his life, a memorable period spent hiking and studying natural history, research of Native American uses of plants, and adventure in the Big Sky country. His interest in Native Americans took him to Harvard University where field work, initially directed to ethnobotanical studies in the Andes Mountains, led the way to a Ph.D. in evolutionary biology and the comparative biology of plants. Jeff eventually returned to California where he followed a path in consulting, growing native plants, and habitat restoration. Building upon this, he became a boat captain and ecotour naturalist. More recently, organic farming with his wife Toni has become a primary focus.

And finally, his broad lifelong interests and background took him to the far corners of California to revisit his passion in evolution, ecology, natural history, and human’s relationship to nature. In this pursuit, he has ventured into many environments and all the major regions throughout the state. An avid photographer, he shares these experiences, thoughts and images in A Natural History of the Golden State and The Nature Connection.

A NATURAL HISTORY OF THE GOLDEN STATE

Course Description

1. Geology: Earth, Water and Climate

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California is largely distinguished by its dramatic geologic landforms. Natural History begins with a description of this physical environment, emphasizing the origins and evolution of the California landscape of mountains, valleys, and coasts. To appreciate California’s unique geology, we explore modern concepts of plate tectonics and continental drift, geologic time, the nature of rocks and minerals, erosion and mountain building, the geologic origins and history of California, a survey of its geologic provinces (such as the Sierra Nevada, Coast and Central Valley), soil formation, water in the landscape and the water cycle, different kinds of waterscapes, and climate. While the perception of California is one of a laid-back human culture, its geological history is one of turbulence, disturbance, and change, and a variable topography fashioned over the great epochs of time. To understand California as a place is to understand how California has been geologically assembled from disparate pieces of earth, fire, and water. California’s special Mediterranean climate of wet, mild winters and hot, dry summers has influenced particular kinds of characteristics among California’s plants and animals. But that isn’t all: California’s tremendous environmental variation of deserts, mountains, and coasts has equally created conditions for high levels of biotic diversity.

2. Plants: Rooted to the Earth

The study of life often begins with plants. We survey general botanical concepts of plant structure and growth, taxonomy, ecology and adaption to particular environments, the role climate, fire and soil environments, and the development of plant communities and bioregions in the California landscape. Unlike animals which are generally mobile, plants are literally rooted to a particular spot, and their presence is highly correlated with the sense of place. Forests, grasslands, deserts and wetlands each convey a very different meaning of place and how animals, including humans, relate to these varied environments. Measured in terms of uniqueness, number of species, and the beauty of wondrous forms, plant life is truly a California phenomenon. Botanists have long recognized the relationship of our climate to our plant life and call this intersection of climate and plants the The California Floristic Province, a region encompassing most of California west of the Pacific crest as well as a small portion of neighboring Mexico and Oregon. In this unusual climatic zone, California nature has evolved new and endemic species, plants (and animals as well) with peculiar life histories and behavioral traits. More than 5,000 plant species live in California’s deserts, plains, mountains, and seashores, and about 40 percent are endemic to the state.

3. Birds: Animals that Fly

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California bird life is abundant and diverse. Numbering about 500 to 600 species, birds are richly diverse in morphology, color, behavior, and adaptation not only to a life of flying but also to survival on land and water. In this lecture we explore various concepts of bird biology in general; these include evolutionary origins, structure (anatomy and morphology), the nature and origin of bird flight, physiology and behavior, the food quest, adaptions to the environment, ecological interactions with the environment, migration, and taxonomy. Birds utilize the California environment of wetlands and uplands, fields and forests, the air and the land, but they haven’t generally evolved very many separate species adapted to narrowly defined niches. In general, birds are made up of widespread species that are at home in many places. In California, many are migratory and just pass through a region, while others spend winter or summer in the Golden State. Some are yearlong residents. But only a few of these species truly are restricted to California. One is the yellow-billed magpie, found mostly in certain parts of the Central Valley. Another is the island scrub jay, which is found on one of the offshore islands (Santa Cruz Island). And yet another is the California condor, recently brought back from the brink of extinction. Birds, being highly mobile, find in California a bountiful environment that supports large populations of many species, but the environment has not fostered many birds to evolve into separate and unique forms. However, in many other ways, California bird life is unique, if not in the evolution of new species, then in the ways the birds congregate and interact with the environment.

4. Mammals: Vertebrates with Fur

California’s former mammal fauna during the Pleistocene dwarfs the current lineup of animals. During the height of the Ice Age about 18,000 years ago, the California landscape abounded with large megafauna, such as mammoths, mastodons, long-horned bison, camel-like species, giant sloths, saber-toothed tigers, dire wolves, and huge running bears. Compared to mammals of the Pleistocene and earlier, today’s mammals are mostly small creatures. In this lecture, we explore the structure, behavior and ecology of California’s mammals. California hosts approximately 197 species of mammals. From a perspective of lifestyle (how they make a living) and morphology (their outward appearance), mammals are very diverse. They may eat vegetation (herbivores), seeds (granivores) or animal flesh (carnivores); some may run fast (pronghorn antelope) while others move slowly (the opossum, a marsupial) or fly, like a bat. Some squirrels can glide, and other fossorial forms burrow through the soil, like the gopher. Larger animals, such as bear, deer, coyote, and mountain lions, generally have geographically large home ranges with little endemism or local evolution, while some smaller mammals with small home ranges may be locally endemic or have evolved

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local races. Examples of animals with large home ranges include mule deer and pronghorn antelope, which may move up to 100 miles between summer and winter ranges. Locally restricted animals include the salt-marsh harvest mouse, island gray fox, and the San Joaquin pocket mouse. Mammal richness is highest in forested areas, especially in the northern part of the state. The Sierra Nevada, Klamath/North Coast, and Modoc regions have up to 73 species of mammals. Most of these are small sized rodents. In fact, about one third of all California mammals are rodents. Compared to other mammals, rodents are rather small in size.

5. Amphibians and Reptiles: Four-legged Animals with Slimy Skin and Scales; Fish: Vertebrates that Swim/ Invertebrates: Animals Without Backbones

Reptiles and amphibians are animals that aren’t as well appreciated as other more charismatic organisms. But amphibians and reptiles perform important ecosystem functions, such as predatory and herbivory services; and they are important denizens of certain regions of the world. Worldwide there are more species of amphibians and reptiles than mammals, even though we claim to live in the “age of mammals.” As representatives of some of the first animals to leave the ancestral aquatic environment and to walk on the earth, amphibians and reptiles represent some of nature’s first attempts at adapting to an ever-changing terrestrial world. As we humans share our ancestry with these scaly and slippery beings, perhaps we should be humble enough to share the earth with them. These lectures outline the general nature and life history of California’s amphibians and reptiles.

Amphibians are found from sea level to mountaintops and on every continent except Antarctica. They are more common in tropical environments, and in cold climates they hibernate. Modern, extant amphibians include about 4,700 to 6,180 species. California boasts 51 native species of frogs, toads, salamanders, and newts. Of the 51 species, about 17 are endemic to California. These include about 14 species of salamanders and newts, and about 3 species of unique frogs. Because amphibians are dependent upon water for part of their life cycle, their range is highly dissected by dry, intervening environments, generally in mountainous regions.

Reptiles consist of about 9,000 living species worldwide, almost as many as bird species and nearly twice the number of mammals. Reptiles are defined as air-breathing, egg-laying, cold-blooded tetrapods having skin covered with scales (snakes have lost their limbs, but are still included within the group). Unlike amphibians, they do not pass any part of their life cycle in water. Unlike birds and mammals, reptiles, being cold blooded, are dependent upon external sources of heat for maintaining body temperature.

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In this lecture we’ll also explore fish in general and, later on, California’s inland fishes—their life history, ecology, and special attributes. For species of fish, the California environment is a harsh one. Changing geologic regimes and climates, especially during the Pleistocene, presented an obstacle for fish survival and pushed the limits of evolutionary change and adaptation. The fish species that have survived have done so largely through morphological, behavioral, and ecological modifications to the California aquatic environment, one that is highly variable over time and space. While other regions may have predictable aquatic environments among and between seasons and regions, California’s hydrologic environment varies greatly from one year to the next and among the regions of the state. A year of extreme flooding, for example, can alternate with extremely dry periods that test the ability of fish species to survive.

California inland, freshwater fish fauna is represented by about 67 to 70 native resident (living in one place) and (migratory) species. California freshwater fish species occur in a wide variety of aquatic environments. Common resident species include trout, minnows, and suckers. Common fish include salmon, steelhead trout, lampreys, and sturgeon.

Invertebrates are animals without backbones and include insects, spiders, starfish, worms, and other “lesser” creatures. While comparatively small animals, they play a huge role in ecological interactions such as pollination, nutrient cycling, and the decomposition of organic debris. In terms of biomass, they far exceed the weight of other, larger animals such as birds, fish, and mammals. In this final section of animal groups, we learn about the general evolution, ecology and natural history of some of California’s less well known animals.

6. Diversity: The Nature of Nature: Environment, History and Diversity

The final lecture summarizes the nature of California’s biodiversity. The California region is recognized as one of the leading biological “hotspots” in the world. What are the contributing factors to this amazing biodiversity? To answer this question, we further explore the role of California’s unique environment, the particular contributions of the different groups of organisms, evolutionary and ecological adaptations and adjustments to the environment, and several organizing themes and trends in patterns of this diverse life.

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