We can lose sight of the central role that seaweed plays in the coastal habitat of Northern California. For while often present before our eyes, the problems of mapping often submerge seaweed forests with any fixity is mirrored by the threatened disappearance of offshore kelp beds in an amazingly rapid timeframe, as creating an actual image capture able to register the extent of kelp forests is sadly mirrored in the diminishing kelp beds off the California coast.
Has predominantly passive registration of location–onshore registration of sites remotely by satellites, from the harrowing images of the spread of fires. We are reminded by maps showing the rapid advance of the burn perimeters of Yosemite wildfires of 2013, North Bay Fires, or the disastrous Camp Fire of 2018. The rapid pace of the loss of these forested lands seems eerily echoed in the shrinking of coastal beds of kelp along Northern California, and correlates to the advance of warming climes.
If we have developed tools to map the continuity, intensity, and growth of forest fires by satellite and drones, the problem of passively registering the loss of kelp forests, and its relation to the advance of urchin beds, removes a part of coastal environments we are in need of mapping. The scale of maps of the destruction of seaweed beds on the California coast are less rooted in real time, but have advanced in striking fashion over ten years, although the ravages of destruction for now seem to remain undersea. But we are less skilled to communicate their crucial place in offshore environments.
The nutrient-rich cold waters of coastal California provided with its rocky seafloor afford a perfect environment for lush kelp forests, that extend up into British Columbia and Alaska. But as waters are warming, with astounding rapidity, we need to ensure kelp beds are mapped, although many are often off the map, and difficult to register, even as their size has come to be threatened by global warming and climate change, in ways that eerily parallel the loss or threats to irreplaceable forested environments. While the nature of the decline of seaweed is not linked to warming waters directly, the shifting ecosystems that climate change has created have caused a drastic and rapid decline of seaweed’s offshore presence that we have yet to fully map. For the passive registration of kelp beds, traced by GPS or captured through aerial photography, is far less hands-on than examination of their extent would warrant, and low-flying satellites of remote sensing offer few possibilities for accurate mapping of their extent. The rapidity of the disappearance to kelp–and beds whose boundaries are shifting in time with the rapidity of the advance of forest fires on the scale of their destruction–pose problems of global dimensions that are pointing for the immediacy of loss of kelp of over 13,000 species whose biodiversity and creation of oxygen by photosynthesis feeds much of the world drives our own ecosystem.
Even a map of globally threatened areas cannot emphasize properly the extent to which the Pacific coastline provides a site of cold waters, ocean upwelling that provides rich mineral nutrients, and sunlight that makes it an especially abundant site of kelp forests, in a true megaregion of coastal ecology whose catastrophic loss is impossible to imagine. Even a map of kelp’s local abundance fails to map its ecoystemic centrality in adequate ways–ways that the diversity of kelp speciation also fails to capture, despite its clear .scientific value to survey the ocean populations that are most risk.
Miller, Lafferty, Lamy, Kui, Rassweller and Reid (2018)/Royal Society Publishing,
The particular vulnerability of the kelp biomass seems to have grown in unexpected ways not only due to climate warming, but to its particular vulnerability to ocean floor sessile predators like purple sea urchins, who are more likely, it is now believed, to eat phytoplankton and microalgae in the kelp understory, rather than kelp itself: however, the role of urchins in diminishing kelp forests, which themselves feed exclusively on sunlight, the combination of how a lack of upwellings due to climate change diminished urchin food supply and the inhospitable nature of warming waters to kelp forests may increase the vulnerability of kelp in coastal oceans.Continue reading