Birds Return after 99 Years
A species of sea bird that had disappeared from California’s Channel Islands, has begun to re-establish itself there. Researchers found about 125 of the California Common Murres on Prince Island, where they lived up to about 1912. About half of the recently re-discovered population appears to be incubating eggs or raising chicks.
“This is an exciting finding – certainly a historic one. The murres appear to have reestablished their former southern range, perhaps benefiting from present ocean conditions,” said Josh Adams, one of the researchers. (Source: USGS)
Egg harvesting and human disturbance of their habitat caused them to disappear. Prince Island is about 40 acres of rocky terrain, and today is not visited as often as it used to be by people. There are now 13 nesting seabirds on the small island. Murres breed on cliff sides, sea stacks and rocky island areas, which are difficult to reach for predators.
In Northern California, Common Murres are abundant, especially at the Farallon Islands and Castle Rock National Wildlife Refuge. At one point many years ago, an estimated 500,000 lived on the Farallons, but overharvesting of their eggs decreased the population to just several hundred. An estimated 12 million eggs were harvested between 1848 and 1900, due to demand created by the Gold Rush. They began to recover until the 1980s, after decades of much less egg collecting. Then they were hit by an oil spill and 10,000 were killed. Murres spend most of their time floating of the surface of ocean water and are very susceptible to oil pollution. The Farallons became a protected area so the murres were able to fully recover.
Common Murres have been recognized for what damage to their population means in environmental terms, “Over the past 30 years, the common murre (Uria aalge californica) has been recognized as a prominent indicator of marine conservation issues in California, Oregon, Washington, and British Columbia, especially regarding oil pollution, certain fisheries, and human disturbance.” (Source: Fish and Wildlife Service) They eat anchovies, sardines and juvenile rockfishes, and can swim to a depth of 500 – 600 feet.
This video provides a small sense of what it is like to visit just one of the islands:
Video of murres on a cliff:
Image Credit: USGS