nest predators. Other suspected nest predators include western scrub jays, snakes, lizards, rodents, and ants. Conservation and threats The black-chinned sparrow is one of the species protected by the Migratory Bird Treaty Act. Its overall population has not been quantified, but its numbers are known to be decreasing. Estimates of its global population range from 450,000 to 1,100,000. The North American Breeding Bird Survey shows that the black-chinned sparrow's numbers declined at an average rate of 5.1 percent annually between 1966 and 2003, while Partners in Flight reports that the sparrow's numbers dropped 62 percent between 1970 and 2014. However, it is known to be poorly sampled by breeding bird surveys in several states, including New Mexico and Texas. It is considered to be a "Bird of Conservation Concern" by the US Fish and Wildlife Service. On the other hand, the International Union for Conservation of Nature considers it to be a species of least concern, due to its substantial population and very large range. The black-chinned sparrow is known to carry several blood parasites, including members of the genera Haemoproteus and Trypanosoma. Specimens carrying West Nile virus have been found dead. Due to its avoidance of edge habitat, the black-chinned sparrow is vulnerable to habitat fragmentation. Because of that vulnerability, it may be a useful species for indicating environmental changes. It may also be adversely affected by climate change; between 2000 and 2020, its breeding range shifted perceptibly northwards. The National Audubon Society predicts that by 2080, none of its current breeding range will still be in use. Its winter range is predicted to be more stable, with some 65 percent of the current area still in use by 2080, and the total area of wintering range in the United States potentially increasing. References Citations Sources External links Black-chinned sparrow abundance map on eBird North American Breeding Bird Survey trend results for black-chinned sparrow Songs and calls of the black-chinned sparrow at Cornell Lab of Ornithology's All About Birds Spizella Birds of Mexico Birds of the United States sparrow, black-chinned sparrow, black-chinned Taxa named by Jean Cabanis Birds described in 1851