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)
“We hold on to hopes for next year every year in western Dakota: hoping that droughts will end; hoping that our crops won’t be hailed out in the few rainstorms that come; hoping that it won’t be too windy on the day we harvest, blowing away five bushels an acre; hoping ... that if we get a fair crop, we’ll be able to get a fair price for it. Sometimes survival is the only blessing that the terrifying angel of the Plains bestows.”
—Kathleen Norris (b. 1947)