It’s never easy (or cheap) to protect one species by manipulating the patterns of another. Nor is it always advisable. But there are times when it’s worth a shot, especially when multiple agencies and states are willing to get involved. To jump into this bird story that turns out to be a fish tale, we’ll start in the middle, when several years ago the US Army Corps of Engineers asked Don Edwards San Francisco National Wildlife Refuge to collaborate on a plan to improve nesting habitat at the Refuge for Caspian terns, the largest and stockiest of the terns.
“It was a win-win for us,” said Don Edwards wildlife biologist Cheryl Strong, who explained that the islands built for water bird nesting habitat in two of the ponds during the South Bay Salt Pond Habitat Restoration Project (ponds SF2 and A16) had enticed very few birds.
The Corps chose seven islands in these two ponds, five for the terns and two for snowy plovers to reduce potential nesting conflicts. The agency delivered tons of gravel and rock by barge and crane to enhance nesting conditions on the islands. To increase the chances that the birds would land, the Corps hired the US Geological Survey to entice the terns with social attraction. Caspian terns are noisy, social birds, and biologists trying to attract them to one nesting spot over another, provide recordings of bird calls and fake companions to simulate a happening scene. Terns are colonial birds. As they migrate north on the Pacific Flyway after spending the winter in southern climes as far as Northern Bolivia, these muscular, fish-eating, diving birds are more likely to stop when they see a colony of other terns.
So far, the numbers are promising. In 2015, USGS biologists counted 224 pairs of breeding birds with 174 fledgling chicks. In 2016, it was 317 breeding pairs with 158 fledglings.
It’s a pull-push approach, said Corps fish biologist David Trachtenbarg. “We’re essentially pushing terns out of the Columbian Basin and trying to pull them to nesting habitat in other locations on the West Coast,” he said.
Tern chick chirping. Video by Crystal Shore, USGS
Get a Move On
It’s not the first time that Caspian terns have been moved. In the early 1980s, they began showing up in greater numbers to the basin, including at Rice Island (river mile 21). With the ideal conditions of a sand substrate from dredging, good visibility, and no predators, the colony grew from 1,000 to 8,700 breeding pairs in a little over 10 years.
Simultaneously, more fish were being produced and tagged in an upstream hatchery. “That’s when we found out that juvenile salmonids, and specifically steelhead, were being impacted by this bird population,” says Corps biologist Paul Schmidt.
Biologists observed that approximately 90% of the terns’ diet at Rice Island was salmonids. In 1999, NOAA required that the Corps do something about the birds. Reasoning that they would do less damage if they had a wider palate of fish to choose from, the Corps moved the terns to East Sand Island by dissuading them from breeding on Rice Island with fencing and human hazing techniques, and by improving habitat at East Sand Island.
The birds complied, and they did expand their palates to include fish from the ocean. Nevertheless, the bird population continued to grow and they ate just as many fish. The agencies had another problem. The population of double-crested cormorants on East Sand Island also grew from 100 breeding pairs in 1989 to 15,000 pairs in 2013, leading to some controversial culls.
Corps Constructed Tern Nesting Sites. Source: USCOE
East Sand Island now has the largest breeding colonies of Caspian terns and double-crested cormorants in the world. NOAA required action to protect the fish again, and the push and pull plan of terns was implemented in 2006. The plan to redistribute the birds included improvement eight acres of tern nesting habitat in Eastern Oregon, Northern California, and the San Francisco Bay, and to reduce habitat at East Sand Island to one acre.
The pull is starting to work. The sites in Oregon and California have anywhere between 40 and 700 nesting pairs. The push, not so much. In their one-acre at East Sand Island, terns are nesting at higher densities than ever seen before. “They really want to stay at East Sand Island and not leave the Columbia River estuary,” said Schmidt.
Taking a Turn in San Francisco Bay
To lure Caspian terns down from the sky to Don Edwards, USGS biologists arrayed more than 500 tern decoys, some of which were painted by local students. They also installed Murremaid Music Boxes with MP3 Players that jam Caspian tern calls.
School kids help paint tern decoys. Photo: Crystal Shore, USGS
This is the third and final year of the social attraction and monitoring phase of the project. The Corps expects more terns to take a liking to Don Edwards because of the fish banquet, and because the species has a history of nesting in the South Bay. The Corps’ goal is 100 to 1,500 breeding pairs. “There’s still time for more Caspian terns to find these islands,” said Schmidt.
If the terns show up and expand in numbers like they did in the Columbia River estuary, what then? Project managers say that the nesting colonies aren’t likely to negatively impact endangered salmonids here. An earlier study by Oregon State University found that salmonids don’t factor significantly in the diet of Caspian terns nesting in South San Francisco Bay.
The pull-push strategy of this management plan has yet to play out. Meanwhile, it’s worth noting that both salmonids and Caspian terns travel great distances and return home with site fidelity. They have that in common. But one can fly over the dams and fish ladders of the Columbia River, and the other cannot, a fact that contributes to one being endangered and not the other. Salmonids also support a large amount of the economy in Oregon and Washington. Terns do not. These factors play into the push and pull decisions that people make about wildlife.
Contact: C. Alex Hartman; David A. Trachtenberg; Genie Moore; Cheryl Strong
“It’s a push-pull approach, we’re essentially pushing terns out of the Columbia Basin and trying to pull them to nesting habitat in other locations on the West Coast”
David Trachtenbarg
Fish Biologist
US Army Corps of Engineers
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Hothouse Earth
By Ariel Rubissow Okamoto
Photo by Megan Nguyen
Nothing could be stranger than sitting in the dark with thousands of suits and heels, watching a parade of promises to decarbonize from companies and countries large and small, reeling from the beauties of big screen rainforests and indigenous necklaces, and getting all choked up.
It was day two of the September 2018 Global Climate Action Summit in San Francisco when I felt it.
At first I wondered if I was simply starstruck. Most of us labor away trying to fix one small corner of the planet or another without seeing the likes of Harrison Ford, Al Gore, Michael Bloomberg, Van Jones, Jerry Brown – or the ministers or mayors of dozens of cities and countries – in person, on stage and at times angry enough to spit. And between these luminaries a steady stream of CEOs, corporate sustainability officers, and pension fund managers promising percentages of renewables and profits in their portfolios dedicated to the climate cause by 2020-2050.
I tried to give every speaker my full attention: the young man of Vuntut Gwichin heritage from the edge of the Yukon’s Arctic National Wildlife Refuge who pleaded with us not to enter his sacred lands with our drills and dependencies; all the women – swathed in bright patterns and head-scarfs – who kept punching their hearts. “My uncle in Uganda would take 129 years to emit the same amount of carbon as an American would in one year,” said Oxfam’s Winnie Byanyima.
“Our janitors are shutting off the lights you leave on,” said Aida Cardenas, speaking about the frontline workers she trains, mostly immigrants, who are excited to be part of climate change solutions in their new country.
The men on the stage, strutting about in feathers and pinstripes, spoke of hopes and dreams, money and power. “The notion that you can either do good or do well is a myth we have to collectively bust,” said New Jersey Governor Phil Murphy whose state is investing heavily in offshore wind farms.
“Climate change isn’t just about risks, it’s about opportunities,” said Blackrock sustainable investment manager Brian Deese.
But it wasn’t all these fine speeches that started the butterflies. Halfway through the second day of testimonials, it was a slight white-haired woman wrapped in an azure pashmina that pricked my tears. One minute she was on the silver screen with Alec Baldwin and the next she taking a seat on stage. She talked about trees. How trees can solve 30% of our carbon reduction problem. How we have to stop whacking them back in the Amazon and start planting them everywhere else. I couldn’t help thinking of Dr. Seuss and his truffala trees. Jane Goodall, over 80, is as fierce as my Lorax. Or my daughter’s Avatar.
Analyzing my take home feeling from the event I realized it wasn’t the usual fear – killer storms, tidal waves, no food for my kids to eat on a half-baked planet – nor a newfound sense of hope – I’ve always thought nature will get along just fine without us. What I felt was relief. People were actually doing something. Doing a lot. And there was so much more we could do.
As we all pumped fists in the dark, as the presentations went on and on and on because so many people and businesses and countries wanted to STEP UP, I realized how swayed I had let myself be by the doomsday news mill.
“We must be like the river, “ said a boy from Bangladesh named Risalat Khan, who had noticed our Sierra watersheds from the plane. “We must cut through the mountain of obstacles. Let’s be the river!”
Or as Harrison Ford less poetically put it: “Let’s turn off our phones and roll up our sleeves and kick this monster’s ass.”
4th California Climate Change Assessment Blues
by Isaac Pearlman
Since California’s last state-led climate change assessment in 2012, the Golden State has experienced a litany of natural disasters. This includes four years of severe drought from 2012 to 2016, an almost non-existent Sierra Nevada snowpack in 2014-2015 costing $2.1 billion in economic losses, widespread Bay Area flooding from winter 2017 storms, and extremely large and damaging wildfires culminating with this year’s Mendocino Complex fire achieving the dubious distinction of the largest in state history. California’s most recent climate assessment, released August 27th, predicts that for the state and the Bay Area, we can expect even more in the future.
The California state government first began assessing climate impacts formally in 2006, due to an executive order by Governor Schwarzenegger. California’s latest iteration and its fourth overall, includes a dizzying array of 44 technical reports; three topical studies on climate justice, tribal and indigenous communities, and the coast and ocean; as well as nine region-specific analyses.
The results are alarming for our state’s future: an estimated four to five feet of sea level rise and loss of one to two-thirds of Southern California beaches by 2100, a 50 percent increase in wildfires over 25,000 acres, stronger and longer heat waves, and infrastructure like airports, wastewater treatment plants, rail and roadways increasingly likely to suffer flooding.
For the first time, California’s latest assessment dives into climate consequences on a regional level. Academics representing nine California regions spearheaded research and summarized the best available science on the variable heat, rain, flooding and extreme event consequences for their areas. For example, the highest local rate of sea level rise in the state is at the rapidly subsiding Humboldt Bay. In San Diego county, the most biodiverse in all of California, preserving its many fragile and endangered species is an urgent priority. Francesca Hopkins from UC Riverside found that the highest rate of childhood asthma in the state isn’t an urban smog-filled city but in the Imperial Valley, where toxic dust from Salton Sea disaster chokes communities – and will only become worse as higher temperatures and less water due to climate change dry and brittle the area.
According to the Bay Area Regional Report, since 1950 the Bay Area has already increased in temperature by 1.7 degrees Fahrenheit and local sea level is eight inches higher than it was one hundred years ago. Future climate will render the Bay Area less suitable for our evergreen redwood and fir forests, and more favorable for tolerant chaparral shrub land. The region’s seven million people and $750 billion economy (almost one-third of California’s total) is predicted to be increasingly beset by more “boom and bust” irregular wet and very dry years, punctuated by increasingly intense and damaging storms.
Unsurprisingly, according to the report the Bay Area’s intensifying housing and equity problems have a multiplier affect with climate change. As Bay Area housing spreads further north, south, and inland the result is higher transportation and energy needs for those with the fewest resources available to afford them; and acute disparity in climate vulnerability across Bay Area communities and populations.
“All Californians will likely endure more illness and be at greater risk of early death because of climate change,” bluntly states the statewide summary brochure for California’s climate assessment. “[However] vulnerable populations that already experience the greatest adverse health impacts will be disproportionately affected.”
“We’re much better at being reactive to a disaster than planning ahead,” said UC Berkeley professor and contributing author David Ackerly at a California Adaptation Forum panel in Sacramento on August 27th. “And it is vulnerable communities that suffer from those disasters. How much human suffering has to happen before it triggers the next round of activity?”
The assessment’s data is publicly available online at “Cal-adapt,” where Californians can explore projected impacts for their neighborhoods, towns, and regions.
The results are alarming for our state’s future: an estimated four to five feet of sea level rise and loss of one to two-thirds of Southern California beaches by 2100, a 50 percent increase in wildfires over 25,000 acres, stronger and longer heat waves, and infrastructure like airports, wastewater treatment plants, rail and roadways increasingly likely to suffer flooding.