Last week Earl and I went to California, and we were mugged. By whales. Three humpbacks. “Mugged” is the official term, meaning we were held up. When whales swim close to a boat, we are required to shut down the engines and propellers and wait until the whales move on. The three humpbacks came right beside us and entertained us with their blows, flips, and dives for about thirty minutes. Neither the experts for our tour or the boating company had ever seen anything like it! Normal behavior for dolphins, but not humpbacks!
Earl and I spent last week at Channel Islands National Park, which lies twenty miles west of Ventura, California. We kept looking at that trip in the Road Scholar catalog, intrigued. All I knew about the Channel Islands was that they were the setting for Island of the Blue Dolphins, which our children read in fourth grade, and that they are often called the Galapagos of the North.
There are eight Channel Islands, running from Santa Barbara to Los Angeles. Five make up the National Park, and these are the ones nearest Ventura, where the visitor center is found. Only one, Santa Cruz, was open to the public in April. They lie above colliding tectonic plates which caused folding and uplifts, creating the islands.
The channel between the California coast and the islands is deep and swift, so the wildlife and vegetation developed in isolation, with many species found nowhere else; endemic, a new vocab word for me.
As is true in the Galapagos, plants and animals that are isolated evolve into new species. Island foxes, spotted skunks, scrub jays, ashy storm-petrels, and sage sparrows are different from those we see on the mainland and exist nowhere else. Plants like the Torrey pine and varieties of oaks, bushes, and flowers are unique to the islands.
Our hikes on Santa Cruz Island allowed us to see many of these species. It was spring in full bloom. So many flowers everywhere!
When we think of mammoths, we envision the 15-foot tall skeleton in Lincoln’s Morrill Hall; the Columbian mammoth which was excavated near Fort Robinson. Its cousin, the pygmy mammoth, was found only on the California Channel Islands, and died out about 10,000 years ago, just like the mainland mammoth. Pygmy mammoths varied from 4.5 to 7 feet high at the shoulders and weighed only about 2,000 pounds.
This phenomenon, where large species that relocate to islands get smaller over the centuries, is called insular dwarfism. The Channel Island fox is the largest mammal on the islands, the size of a house cat, weighing about four pounds. Small species like many of the birds and mice evolve larger, called insular gigantism.
Channel Islands provide major breeding grounds for elephant seals, sea lions, and brown seals. Breeding colonies of brown pelicans, ashy storm petrels, and several types of gulls exist on the more remote islands.
The channel is a major whale area because of its depth. Warm southern currents meet the cold currents coming the north, and their churning brings exceptional nutrition in the waters for all the marine life. This time of year the gray whales are moving from their summers off the coast of Mexico to Alaska. The grays we saw were moving right along! Blue whales are around in the summer. In winter the humpbacks play in the waters. And so many dolphins!
The waters around the Channel Islands are filled with kelp forests. Because of the mixing of both warm water currents from the south and cold currents from the north, an incredible abundance and diversity of marine life is supported. Many people come to the Channel Islands for scuba diving and snorkeling in these kelp forests.
We would have guessed that these islands had not been populated because of the difficulty of getting to them. However, they have provided the earliest evidence of both seafaring and settlement in the Americas. A femur has been found on one of the islands that dates to 13,000 years ago! The Chumash were the indigenous people. Like most Native Americans, they were decimated by diseases brought by Europeans.
In the mid-1800’s the islands were purchased and turned into ranches, first for sheep, then pigs, and finally Herefords. When the islands became a national park in 1980, these animals were removed from the islands, and native species are being restored. There is also work to remove the other invasive species that were brought by those settlers.
Enough about our trip. Next week we’ll talk about why our National Parks are so important.