(originally commissioned for the Living Alongside Wildlife blog)
The valley of the shadow of death
The last chapter of our California journey brought us to a very different ecosystem.
While driving from Yosemite to Shasta my father and I crossed the Central Valley. This valley was once an extensive grassland and wetland system that spanned most of the length of California from Bakersfield to Redding. The Central Valley held a unique herpetological assemblage that included California Tiger Salamander, Western Spadefoot, Blunt-nosed Leopard Lizard, Giant Garter Snake, and San Joaquin Coachwhip. Many other endemic fish, mammals, invertebrates and plants were found in its waters.
In the 1850s, disillusioned gold miners migrated into the valley and began converting it to cropland. The year-round sunshine and excellent soil were perfect for agriculture. Dams soon blocked off rivers that fed the valley’s wetlands; marshes that remained were drained and planted. What herps survived had to adapt to agriculture or be constrained to small pockets of habitat.
One species that has had a tough time adapting is the Giant Garter Snake. It is the world’s largest garter snake and among the most aquatic. Wherever wetlands were drained and dryland crops were planted, it disappeared. The Giant Garter Snake is now missing from 98% of its former range in the San Joaquin Valley (the southern portion of the Central Valley) and has lost most of its habitat to the north as well.
A few remaining Giant Garter Snakes are hanging on in limited spots where marshes remain. Others survive in those irrigation canals which retain sufficient cover vegetation, feeding on introduced warmwater fish that have replaced their natural food supply. In the right spots these snakes even venture into flooded rice fields. An effort has been made to preserve some of these heavily-altered habitat mosaics and keep the species from going extinct.
My father and I pulled off the highway and drove up to a newly established preserve. A canal sliced across the landscape, separating ongoing crop planting on one side from newly overgrown fallow fields on the other. The habitat was loaded with threats. Roads crossed everywhere, agricultural runoff flowed into the water, and evidence of fishermen abounded.
As we reached the canal, my father spotted a body. We stopped to find a dead juvenile Giant Garter Snake, killed by a passing car. I walked over to the edge of the canal and saw another dead garter in the water. Pulling it out, I found it had been trapped in the tattered remains of a discarded fishing net, drowning as a result.
Then a huge snake on the opposite side of the road launched itself off the canal’s banks and dove into the water, all slippery momentum and grace. We had a live one!
My father and I left the spot alone for half an hour to search other roadside canals, then came back more stealthily than before. The snake had returned to its sunning spot on the bank, and this time it allowed me to approach. Nearly a meter in length and as thick as any garter snake I’d ever seen, its stature was as impressive as its resilience. But does it represent a new start for the species, or a final straggler destined to meet the same fate as its brothers, caught by traps or cars or other hazards in a landscape no longer its own?
In the presence of many enemies
The State of California lists 22 species of reptile and amphibian as “threatened or endangered” and another 44 as of “special concern” due to declining range and populations. Thus a third of California’s herps are officially in trouble, and in fact nearly all species have shown recent declines. A longitudinal study by Sam Sweet found that snake observations across his study areas dropped by over 90% between 1980 and 2010. This held true even for common species like gopher snakes and ringnecks, the sort of herps that we would rarely worry about.
In an ideal world, we could identify the threats to wildlife one-by-one and then work to reduce them. Unfortunately, the threats may be too numerous for this piecemeal approach. In this blog series I’ve identified herps in trouble due to urban sprawl and rural agriculture, irrigation and drought, fire and dams, chytrid fungus and global warming, highway construction and off-road ATVs, garbage dumps and livestock grazing, pesticides and invasive plants, roadkill and hiking impacts, logging, mining, fishing, and all kinds of introduced predators.
That list is not exhaustive – human existence infringes on herps in almost every facet. I could also have written of the perils of sound pollution (disrupts some auran breeding near roads), light pollution (impacts life cycles near urban areas), or renewable energy development (takes over large tracks of land in the desert). Other threats may not yet be known. We often address one threat only to see another crop up, or improve the situation for one species then find that our actions have indirectly harmed others.
Due to the number and complexity of the threats, species are often lost before we even knew what hit them. We would like to think that we understand conservation more now than when previous native herps went extinct, yet in recent years we continue to see species appear to blip off the map (Northern Leopard Frog, Desert Slender Salamander) without being able to do anything about it. If another vulnerable species becomes extirpated over the next decade – say, the Regal Ringneck Snake or Cope’s Leopard Lizard, the Lassen Cascades Frog or Lesser Slender Salamander – we might be just as ignorant as to what had happened. Even when we do know what is happening, coordinating large-scale conservation efforts is difficult. There might be nothing we could do before the animal is gone.
Still waters in green pastures
After a night in Shasta my father and I embarked on our last full day of the trip. We hit a few spots in the Siskiyous and then crossed the border into Oregon. Staying within state lines was not an option; our final target, the Oregon Spotted Frog (Rana pretiosa), is extinct in California.
From my childhood home near Portland, I grew up hearing stories about the decline of this unique and beautiful red ranid. One of the most aquatic frogs in America, it prefers to spend its time floating in water rather than sitting on shorelines. It breeds in highly vegetated shallows but survives summers and droughts in deeper permanent water, and its reluctance to travel overland between these habitats leads it to require complex, diversified wetland systems in order to survive.
Sadly, most such wetlands have been filled in for agriculture, polluted by fertilizer and pesticide runoff, destroyed by cattle grazing, overgrown with invasive foreign grasses and reeds, or overtaken by predatory bullfrogs. The last confirmed record of a spotted frog in California was in Modoc County in 1989. Though still found in a few localities in Oregon, Washington, and British Columbia, they have disappeared from 95% of their former range.
My father and I drove up into the eastern slopes of Oregon’s Cascade Mountains, home to most of the remaining spotted frog populations. In late afternoon we arrived at the necessary complex wetland system, free from bullfrogs and out of range of cattle grazing and agricultural runoff. A beautiful stream twisted through long grass, stretches of flooded meadow connecting its waters to several small but deep ponds.
I scanned the surface of one pond until I saw tell-tale upturned eyes protruding from the water. After 30 years of hearing about this endangered species, I was observing one in the wild. My heart pounded as wonder overtook me – it was like a myth in the flesh. I felt lucky, blessed. The longer I stood, the more frog shapes resolved. I counted nine spotted frogs and several tadpoles in this single water body. Others floated in an overflow pool adjacent to the stream, and more still were found in a marsh a few miles away. In at least this one spot, far from human development, they are strong.
Conservationists are working to create hope for the Oregon Spotted Frog, even in Washington where only seven populations of the species persist. For several years the Washington Department of Fish and Wildlife worked in conjunction with zoos and a corrections facility to run a reintroduction program. Spotted frog eggs from Conboy Lake Wildlife Refuge and the Black River were brought to captive facilities, where they were raised to adulthood and then released into a new preserve. The largest and healthiest frogs were those raised by inmates, perhaps because they gave the most time and attention to their care. Unfortunately, the reintroduced frogs failed to prosper at the new locality. Other reintroduction projects have followed and are showing somewhat more success.
As with the frogs discussed in the previous essay, all hope depends on the persistence of habitat. These reintroduction efforts will only matter if the wetlands aren’t drained and the meadows aren’t developed. Only if cattle don’t overrun the spots and agricultural runoff doesn’t poison them. Even with all the researcher help in the world, the spotted frogs will continue to face a complex of threats.
Looking forward to forever
What can we Californians do to address all these threats to all these species in a manner that has any chance of preserving our biodiversity for future generations? Is there any way for us to stop playing catch-up, to learn to preserve life rather than destroy it?
A necessary part of the answer, in my evaluation, is that we adopt holistic conservation measures that address many of the threats at once. And the easiest way to address many threats at once is to reduce our ecological footprint by reducing our consumption.
Over the last 70 years American consumption patterns have increased dramatically. Everything we do seems to have been super-sized, from our homes to our cars to our meat intake to our discarded trash. Some calculations suggest that the average American now has the ecological footprint of 40 people in Bangladesh, or 200 people in Ethiopia. And there is no evidence that this recent increase in consumption has made us happier – in many cases it’s quite the opposite. The root of the trend towards overconsumption isn’t personal benefits, but the corporate need to continually increase production, thus inundating us with advertising that suggests we will not be happy unless we discard all that is old, buy everything new, and constantly, constantly “upgrade”.
It is unlikely that corporations will lose their desire to see us consume more. Nor will our government work against their most well-heeled lobbyists. Thus is it up to individuals and families and communities to learn to reduce our impact.
Will we choose to live in smaller homes on smaller plots in order to limit residential sprawl and driving miles? Will we adjust our diet to reduce our agricultural footprint? Will we refrain from replacing commercial goods with every new season or fad, so that we can minimize our resource depletion and waste production?
Rough estimates suggest that Earth’s consumption patterns are already 20% higher than sustainable levels – in other words, the Earth would have to be 20% bigger for us to use as much stuff as we do every year without eventually depleting all of it. It’s worse in America – if the entire world’s population consumed goods like Americans, we would be at 400% of sustainable consumption. It would take four Earths to supply our needs. And America’s over-consumption doesn’t only affect America’s wildlife – our raw material extraction, fishery depletion, factory pollution, and even trash disposal has been outsourced to much of the rest of the world.
An “advantage” of globalization is that we don’t have to see all the consequences of our choices. But even when we outsource much of our impact, there are still repercussions right here in California. Dams, logging, dumps, sprawl, agribusiness – it’s in front of our eyes. And whatever we may hear about backroom dealing in the “water wars” or politicians’ calls for “drill baby drill!”, the profitability of development comes down to you and I and our continued obedience to a system which tries to limit our choices to “more” and “much more”. However much energy, water, home, car and agriculture we want to pay for, they will produce. Our use drives their profits. That choice is in our hands.
The theme I saw throughout our trip was that despite the threats to California’s wildlife, there remains a good chance that our herps can persist so long as the habitat is still there. Every year we lose more of that habitat. The toads are being forced into gaps of stream between dams. The garter snakes are scratching out an existence in canals instead of marshes. Some of us herpers have taken to searching empty lots as native meadows become few and far between. We know the animals weren’t meant to live this way. And in the long run, they may not be able to live at all.
Yet every one of those issues is the result of how we have chosen to live. How much more of their habitat we will use up before we reach for a different way?
References:
Thomson, Robert C. California Amphibian and Reptile Species of Special Concern. University of California Press. Kindle Edition.
Nafis, Gary. California Herps: A guide to the reptiles and amphibians of California. http://www.californiaherps.com/
“Imperiled frogs thrive in inmates’ gentle hands”, article published in The Olympian by Stacia Glenn
Thanks to Jackson Shedd and Will Flaxington for their information on historical prevalence of Pygmy Short-horned Lizards at specific sites
A heartfelt word of thanks to Shanti Mathias for all of the assistance on the series
Reptiles and Amphibians of Thailand 