The looming threat of El Niño has scientists concerned about the future of seabirds along the California coast. As I walked along a San Diego beach, the sight of dead seabirds, some hidden under rocks, others mixed with kelp, was a grim reminder of the impact of climate change on our ecosystems.
The surveys conducted by dedicated volunteers and scientists provide a crucial baseline for understanding these die-offs. What's particularly concerning is the way record-breaking ocean temperatures are affecting the food chain, leading to starvation among species like brown pelicans, loons, and grebes.
One of the most heartbreaking aspects, as described by marine ornithologist Tammy Russell, is the rapid decline of cormorants. These birds, usually so resilient, are now walking to shore and dying within minutes. It's a stark illustration of the severity of the situation.
The Impact of El Niño
El Niño, a natural phenomenon, adds an extra layer of worry. With its ability to alter weather patterns worldwide and raise global temperatures, it has the potential to exacerbate the current marine heat wave. The US National Oceanic and Atmospheric Administration has confirmed its formation, and its strength is expected to be historic.
The persistence of the marine heat wave off the west coast for an entire year is unprecedented. Scripps' daily temperature measurements at coastal stations along California's coast reveal record-breaking temperatures at three stations for over 40 days. This data, collected in various ways, paints a concerning picture.
Robotic underwater gliders have also recorded high temperatures offshore, indicating the depth of this issue. Dan Rudnick, who oversees the Scripps glider program, compares the current warm anomaly to the 2023 El Niño, a worrying sign of things to come.
Seabird Adaptations and Challenges
Seabirds, like the Booby species Russell has studied, are adapting to warmer ocean temperatures. However, this adaptation comes at a cost. As cold-water species move deeper and farther north, the disruption to the food web is significant. Gray whales and seabirds are facing challenges in finding sustenance.
The impact of the marine heat wave coupled with El Niño could be devastating. A similar pattern was observed a decade ago, and Russell's concern about the unknown extent of this die-off is valid.
Wildlife rehabilitation facilities have seen an influx of emaciated birds this spring. The unusual sight of brown pelicans turning up in inland lakes is a sign of their desperation for food. These birds, known for their fishing prowess, are now chasing boats and ending up with injuries from fishing gear.
Most of the dead or debilitated seabirds examined this year have been young and severely malnourished. While avian flu has been ruled out, opportunistic infections linked to malnutrition are common. Krysta Rogers, a senior state environmental scientist, suggests that high mortality rates among young Brandt's cormorants and common murres may be due to their inability to survive on their own, but the impact of the marine heat wave cannot be ignored.
The Scale of the Problem
The 2013 'blob' event, which overlapped with one of the strongest El Niños on record in 2015, provides a chilling preview. The die-off of common murres, which resembled thin penguins, was the largest recorded in the world's oceans. These birds, with their high metabolic needs, were unable to find sufficient food, leading to a catastrophic decline in their population.
Studies suggest that only a fraction of birds that die at sea wash ashore, meaning the true extent of these die-offs is often underestimated. It took years for scientists to confirm the death of over half of Alaska's common murres during the 'blob' event.
As we face the potential of another significant die-off, the question arises: Are we doing enough to protect these vulnerable species and the ecosystems they depend on? The answers are complex and often tied to our collective actions and inactions on climate change.
In my opinion, this issue demands our attention and action. The health of our oceans and the creatures that depend on them is a reflection of our own well-being and the health of our planet.
