Highway 161 carries me along the Oregon and California border as I head toward Lower Klamath National Wildlife Refuge. I wish I were visiting it under better conditions. In better time this is a place where birds gather in abundance, feasting and fattening up as they continue their migration along the Pacific Flyway. Sadly, I’m here to witness a massive outbreak of disease — one that’s wiping out tens of thousands of birds.
The Lower Klamath refuge is a “must see,” especially at the start of fall migration. Designated as an “Important Bird Area” by the National Audubon Society, it’s one of a mosaic of refuges in the Klamath Basin that form an essential pinch point along the Pacific Flyway, causing waterbirds to congregate in huge numbers during migration. Birds coming south from Alaska stop to rest and refuel before continuing their journey south to estuaries along the coast, the Sacramento and San Joaquin Valleys of California, and beyond that as far as the tip of South America. The birds can’t complete their journey without places like the Lower Klamath along their route.
This year, though, instead of broad sheets of water, green wetland stands, clouds of mosquitos and throngs of noisy waterbirds, what greets me is a dry, barren landscape baking in the hot summer sun. Throngs of birds cram together in the few pools of hot, stagnant water that remain. Different species and guilds gather in a motley collection of unlikely neighbors; American white pelicans waddle near elegant black-necked stilts and American avocets, rather than spreading out across the open water and mudflats. These are exactly the kinds of conditions where disease can spread rapidly.
It’s not surprising, then, that an avian botulism outbreak is ravaging the birds of the Lower Klamath and some of the surrounding refuges. At last estimate 40,000 birds have died in the last month due to botulism, and thousands more are at an emergency “duck hospital” operated by staff from Bird Ally X, California Waterfowl Association and the U.S. Fish and Wildlife Service.
Avian botulism is a waterborne bacterium, Clostridium botulinum, that occurs naturally in many wetlands but becomes activated when the water temperature rises. Overcrowding caused by insufficient water supplies have created ideal conditions for bacteria to spread rapidly through the birds in the refuge. Birds eat infected food sources, become paralyzed and die, and in turn transmit it to other birds in a vicious cycle that spreads quickly across the wetlands.
Overcrowding, combined with a lack of water supplies to maintain these wetlands and push clean water through their habitats, exacerbates the outbreak as water sits and concentrates.
Making matters worse, some species of waterbirds are molting and will be unable to fly to better habitat for approximately a month. A 2016 study by Point Blue Conservation Science (Barbaree et al.) showed that dowitchers rely on Klamath Basin as a staging ground during molting, staying there for roughly 32 days between July and October while replacing flight feathers. The length and timing of their stay and the lack of flight feathers makes dowitchers and other waterbirds particularly vulnerable to disease outbreaks in this region.
This combination of deadly circumstances for the birds in Klamath has left biologists and refuge managers scrambling for solutions.
To minimize the spread of the infection, biologists and volunteers are capturing thousands of sick birds every day and removing dead birds before they can infect others. They will have to keep this up until temperatures drop considerably, since it will take several nights of freezing temperatures to kill the bacteria.
Refuge managers are also looking for new sources of fresh water to flood more habitat and spread the birds out, a difficult challenge in a dry year like this one. Recent news of additional water being delivered by the Bureau of Reclamation offers some hope, but it may be too little, and it is definitely too late to help those birds that have already perished.
The only true, long-term solution is to ensure that wildlife refuge has secure, reliable water supplies to maintain sufficient wetland habitat for the hundreds of thousands of birds that rely on it. This is not an easy fix, since there’s rarely enough water in the Klamath to meet the needs of tribes, farmers, ranchers, endangered salmon and birds.
Stakeholders have been working for years to reach an accord to accommodate all these important needs, but a satisfactory solution remains elusive, and wildlife refuges have not been highly prioritized. The tens of thousands of dead birds at Klamath are a sign of the stakes and the need for a balanced solution now.
As I leave the refuge, I come across two birders standing in the heat, staring at the Lower Klamath National Wildlife Refuge sign. I want to stop and warn them to not travel any farther into the parched land — that there isn’t anything to see, at least anything pleasant. But I hold back. Perhaps it’s important for all of us to see and understand the tragedy occurring in this remote corner of California and Oregon.
It reminds us of how the refuges that make up the Pacific Flyway are the last, critical links in the long but fragile chain of the Pacific Flyway. We’re linked together through these birds and habitats, across borders, culture and time, and what we do at each of these places — such as our decisions about who does and doesn’t get water — has lasting consequences for our birds, our people and future generations of both.
The opinions expressed above are those of the authors and do not necessarily reflect those of The Revelator, the Center for Biological Diversity or their employees.
This story was first published by Audubon California.
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