Breaking the Ice and Making Connections
September 15, 2015
The Ridgway’s Rail and the Adélie Penguin – both birds by definition, but their biology and ecosystems couldn’t be more, ahem, polar opposite. Splitting my time between studying these two species reveals both contrasts and connections.
Most of the time I am a San Francisco Bay Biologist, counting rails in tidal marshes, but for the last two years I’ve packed my bags and migrated south – far south – to count penguins on Ross Island, Antarctica. For a few months my worldview is literally flipped upside down (and I’d be gazing at very different stars if the sun ever set during my summer at the bottom of the Earth).
One typical April morning this year, I was out to count rails along the Napa River. On this particular morning as I passed the Mare Island Naval Shipyard I happened to see the Coast Guard’s icebreaker, Polar Star, dry-docked for maintenance. I had seen this same ship just a few months before, breaking up sea ice in McMurdo Sound (Antarctica) to forge a path of open water to the American base station. Standing by the ship’s side was a lone Emperor Penguin, probably feeling (as I did), dwarfed by the massive boat.
The waters of San Francisco Bay and the Southern Ocean of Antarctica are vastly dissimilar, yet the Polar Star points towards a connection. As I navigated along the Napa River in the pre-dawn light, I began to wonder if the rail’s and penguin’s struggle for existence in our changing climate are not so far apart.
Rails, Restoration and Rising Tides
The California Ridgway’s Rail, archetypal secretive marsh bird, is endemic to the tidal marshes of San Francisco Bay. It must eke out its existence amongst the 7 million people who also call the Bay Area home. For as long as people have been around the Bay, they’ve been competing with the “marsh chicken” for real estate.
One of Point Blue’s study sites is a 30-hectare (74-acre) rectangle of pickleweed in the North Bay. Every edge of this marsh is encroached upon by either a boardwalk lined with houses, a ferry terminal, San Quentin Correctional Facility, Macy’s department store or the rising tides of San Francisco Bay. Population models by Point Blue, based on surveying sites like this, estimate that only 1,100 Ridgway’s Rails remain in the Bay. To the rail, that remnant of marsh is much more than a carpet of pickleweed – it’s a complex network of channels where the daily tidal cycle delivers sediment, nutrients, and the rails’ dinner into the marsh.
Technical reports on Bay tidal marshes often start with a statement such as: Nearly 90% of historic tidal marsh around San Francisco Bay has been “lost” — elsewhere we learn that humans have paved over, filled, and otherwise destroyed this ecosystem that’s home to the rail.
Over the past few decades there has been a turning of the tide, so to speak, in the minds of Bay Area residents. Humans are reconsidering the importance of mud. We have learned how marshes perform ecosystem services like providing a buffer between surging storm water of the Bay and nearby roads and houses.
Programs around San Francisco Bay to restore tidal marshlands are the most ambitious in the U.S. My job of counting birds helps measure the success of these restoration efforts. Sites that just 20 years ago were fallow land – like Carl’s Marsh, at the mouth of the Petaluma River – are now thriving with rails and other marsh-dependent species.
Our Bay waters are cleaner, and harbor porpoises have returned, but we have a long way to go to restore marshes that will stand up to the rising tides of the future.
Adélie Penguins spend their lives on and near a partially frozen sea, where the network of species’ relationships are as natural as they were millennia ago. No human calls Antarctica home, but the penguin is not immune to the influence of the 7 billion people living to the north. Today there’s a battle in the Southern Ocean — on the high seas, which belong to no single nation or entity — over a fish that no one quite understands, but which we may be eating to extinction.
Removing the long-lived toothfish (a.k.a. Chilean Sea Bass) from this near-pristine marine food web could have disastrous effects on all its members- from killer whales to krill. Global warming’s effects are seen on the southernmost continent as well, and the extent of sea ice has declined in certain regions beyond what Adélies need for foraging and Emperors need for breeding colonies. For the near term however, Adélies may continue to find optimal conditions in the Ross Sea, the last holdout for all ice-dependent species.
The penguin, like the rail, needs people to protect a fragile ecosystem. To do that, we need to understand them well.
They’re Counting on Us
Counting birds. How can this ever translate into saving a species, an ecosystem, or an entire ocean? The task can seem as daunting as the Antarctic landscape. We can only enact ocean or marsh protection policies with scientific data backing them. Simply put, I’m counting birds so we can coexist, from the Bay to the ice. The more we discover in both of these ecosystems, the more we can benefit and conserve their integrity.
As the climate changes, both rails and penguins will lose real estate. The seas will rise, drowning marshes, and the perfect balance of a frozen ocean may tip in the wrong direction for Adélies. Counting birds (as biologists); understanding their ecosystems (as citizens); and continually asking questions and sharing discoveries (together): these are the ways to arrive at solutions that benefit all of us – including the rail and the penguin.
2014 Annual Report to U.S. Fish and Wildlife Service: California Ridgway’s Rail (Rallus obsoletus obsoletus)
The State of the Birds San Francisco Bay 2011 website
Future San Francisco Bay Tidal Marshes, a Climate–Smart Planning Tool