European swallows typically live for two to four years, although the maximum recorded lifespan is nine years, with a theoretical lifespan ranging from eleven years and two months to sixteen years; the age at which they reach sexual maturity ranges from nine months and one week to one year and three months. The embryo develops inside an egg, and the young bird’s eyes open between five and six days of age. The nestling stage involves the young being fed insects by its parents and lasts from two weeks and four days to three weeks and one day. Following this, the species enters a period of rapid growth, lasting from one to three months, where the young bird learns to fly and hunt independently. The adult stage, during which the swallow is capable of reproduction and long-distance migrations, lasts from one to eleven years.