What is the life span of a swift?

Answer 1

Swifts - birds of the family Apodidae - have adult mortality rates of around fifteen percent, which corresponds to a life expectancy of around six years.

Although this may not seem long, swifts are for their size, which ranges from ten to one hundred grams, about the longest-lived of all vertebrates. Most animals of the mass range swifts occupy can expect to die in less than one year, with adult mortality rates of around seventy percent for birds to over ninety percent for non-flying mammals. Even in the tropics, Australia and Southern Africa resident birds of these masses have life expectancies of two to three years.

The reason swifts are so long-lived is that except when breeding they spend their entire time flying, where most predators simply cannot catch them.