Gathering of Whales
Attracted by Krill Which Are in Turn Attracted by Channel Upwelling Caused by Wind
Sunday, September 25, 2011
On the white rocks, I can see the yellow heads of young pelicans, they are nervous of my presence. Walking on a small beach, I can remember my first sight of the blue whales that have returned to the marine areas of our region.
The krill, tiny shrimp-like organisms, are attracted to the ocean upwelling in the Santa Barbara Channel. Ocean upwelling is caused, in part, by the strong winds that blow north of Point Conception, which bring up nutrient-rich waters from the bottom of the sea that are essential for marine life to thrive. The blue whales are attracted to the presence of krill. On a boat trip out to the islands this time of year, you may notice a group of blues whales rising out of the depths of the sea, spinning and spy-hopping as if they were celebrating. They are feeding on krill. You are witnessing the gathering of whales.
The islands offshore should be considered a “Noah’s ark” of the sea; the islands to our oceanic horizon are home to an abundance of endemic and migrating species. The area is the Galapagos of the Northeast Pacific Ocean. At least 27 species of whales and dolphins have been sighted in the channel and about 18 species are seen regularly and are considered “residents.” Over 60 species of marine birds may be using the marine and coastal waters of our region to varying degrees as nesting and feeding habitat, for wintering, and/or as migratory or staging areas. San Miguel Island supports the most numerous and diverse avifauna, with nine species having established colonies. Santa Barbara Island has several nationally and internationally significant seabird nesting areas, including the largest nesting Xantus’s murrelet colony and the only nesting site in the United States of black storm-petrels. The brown pelican maintains its only permanent rookery in California on Anacapa Island.
The northern Channel Islands have a remarkable natural history. Portions of coastal areas on the northern Channel Islands were sites of Chumash villages, and are now submerged by changes in sea level. The Chumash references for the northern Channel Islands are Tuqan (San Miguel), Wi’ma (Santa Rosa), Limuw (Santa Cruz) and Anyapax (Anacapa). Limuw means “in the sea is the meaning of the language spoken,” while Chumash villages were named after the sea, such as Mikiw or “the place of mussels.” Thousands of years ago, the sea level was at least 150 feet lower than it is today, and the northern Channel Islands were joined as one island. Recently discovered paleontological remains have also contributed to the rich record of the coastal area. In 1994, for example, a relatively complete pygmy mammoth was discovered on a coastal bluff on the north shore of Santa Rosa Island. This discovery represents the most complete pygmy mammoth discovered in the world. Early human remains of a woman (“Arlington Springs Woman”) were discovered at Arlington Canyon on Santa Rosa Island, dating back to the end of the Pleistocene, approximately 13,000 years ago.
In 1948, John Steinbeck’s Cannery Row was published. One theme of the book is on the changing maritime culture of Monterey after the collapse of the sardine fishery. Partially in response to the collapse of the fishery, in 1950 a group of diverse scientists along the coast of the state formed the California Cooperative Oceanic Fisheries Investigations or CalCOFI. This partnership of scientists began to study the ecology of the region, and have continued to investigate the abundance of birds, plankton, fishes, invertebrates and other marine life, including the important factors that influence the dynamic marine area, such as changes in sea surface temperature and the currents. The information collected from these scientists gives us a remarkable history of the complexity of the marine areas off our coast.
One lesson learned from scientists is that the presence of blue whales and other marine life of this region depend on complex ecological relationships between the currents, the winds, the climate, and habitats. These relationships change over time and are often driven by subtle variation in sea surface temperature. For example, the abundance of kelp forests off of our region’s coast is influenced by water temperature and the currents, pollution from the coastal mainland, storm activity, and the presence of other life forms like urchins and their predators, the southern sea otter.
The presence and abundance of blue whales and sea birds off our coast is influenced by human activities. Today, scientists are describing the synergistic and cumulative impacts of human activities. Human impacts, such as habitat loss and pollution, and climate change can influence the biodiversity of the region. Studies by Dr. Ben Halpern and colleagues at the National Center for Ecological Analysis and Synthesis in Santa Barbara have included analysis of the impacts of human use and climate-related factors on the California Current, which is the major oceanographic current offshore Santa Barbara. They show many areas of high impact and few marine areas of low impact. In particular, scientists show that parts of the nearshore marine environment include areas of high human impact. One reason is that nearshore marine areas are in close proximity to coastal areas, and pollution from coastal landscapes influences marine life. The studies by Halpern and others are contributing to a new understanding of the human and natural impacts to marine environments. These studies have led to the creation of an “ocean health index” that can be used to better understand how human beings are influencing the ecology of the oceans.
With increasing evidence of large-scale migration of marine species, such as marine mammals and sea birds, it is important that we recognize our role as marine stewards: We need to respond to the increasing pressures, threats and associated impacts that human beings have on coastal marine ecosystems. One challenge today is to understand how human activity that takes place far from a coastal and marine area can influence the health of marine life. Although we may believe that our actions on land have little impact on the oceans, the fact is that all human activity may have dramatic consequences. The blue whales are attracted to our region because of the bounty and health of the Channel. We should not take this for granted.