colonies and the female lays one white egg. These shearwaters nest in burrows lined with plant material, which are visited only at night to avoid predation by large gulls. The architecture of sooty shearwater burrows can vary within and between breeding colonies, and is influenced by competition for breeding space and habitat type, with soil under dense tussac grass being easier to excavate than other substrates. In New Zealand, about 250,000 muttonbirds are harvested for oils and food each year by the indigenous Māori population. Young birds just about to fledge are collected from the burrows, plucked, and often preserved in salt. in 2022, climate change was thought to be impacting this cultural harvest by Ngāi Tahu. Its numbers have been declining in recent decades, and it is presently classified as near threatened by the IUCN. In 2009, the harvest reported record-low catches, on average a trapping cage yielded nearly 500 birds; in 2009, the number was estimated to be closer to 40 per cage. Inspiration for Hitchcock's The Birds On August 18, 1961, the Santa Cruz Sentinel reported that thousands of crazed sooty shearwaters were sighted on the shores of North Monterey Bay in California, regurgitating anchovies, flying into objects, and dying on the streets. The incident sparked the interest of local resident Alfred Hitchcock, along with a story about spooky bird behavior by British writer Daphne du Maurier, helping to inspire Hitchcock's 1963 thriller The Birds, a cautionary tale of nature revolting against man. The film is now ranked among the American Film Institute's top-10 thrillers of the last century. Scientists looking at the stomach contents of turtles and seabirds gathered in 1961 Monterey Bay ship surveys have found toxin-making algae were present in 79% of the plankton the creatures ate. "I am pretty convinced that the birds were poisoned," says ocean environmentalist Sibel Bargu of Louisiana State University. "All the symptoms were extremely similar to later bird poisoning events in the same area." Plankton expert Raphael Kudela of USC points to leaky septic tanks installed amid a housing boom around Monterey Bay in the early 1960s as the ultimate culprit that may have fed the toxic algae: "It is to some extent a natural phenomenon, and the best thing we can do is monitor for the presence of toxins, and treat impacted wildlife." References Further reading Bull, John L.; Farrand, John Jr.; Rayfield, Susan & National Audubon