Survival
In adult House Sparrows, annual survival is 45-65%. After fledging and leaving the care of their parents, young sparrows have a high mortality rate, which lessens as they grow older and more experienced. Only about 20–25% of birds hatched survive to their first breeding season. The oldest known wild House Sparrow lived for nearly two decades; it was found dead 19 years and 9 months after it was ringed in Denmark. The oldest recorded captive House Sparrow lived for 23 years. The typical ratio of males to females in a population is uncertain due to problems in collecting data, but a very slight preponderance of males at all ages is usual.
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Famous quotes containing the word survival:
“... survival is the least of my desires.”
—Dorothy Allison (b. 1949)
“However great a man’s fear of life, suicide remains the courageous act, the clear-headed act of a mathematician. The suicide has judged by the laws of chance—so many odds against one that to live will be more miserable than to die. His sense of mathematics is greater than his sense of survival. But think how a sense of survival must clamour to be heard at the last moment, what excuses it must present of a totally unscientific nature.”
—Graham Greene (1904–1991)
“It is almost as if you were frantically constructing another world while the world that you live in dissolves beneath your feet, and that your survival depends on completing this construction at least one second before the old habitation collapses.”
—Tennessee Williams (1914–1983)