The average population of these
common birds has fallen 68 % since 1967; the 20 birds listed on the national «Common Birds in Decline» database (including such perennial favorites as the Common Tern and Field Sparrow) have lost at least half of their populations during that p
common birds has
fallen 68 % since 1967; the 20 birds listed on the national «
Common Birds in Decline» database (including such perennial favorites as the Common Tern and Field Sparrow) have lost at least half of their populations during that p
Common Birds in Decline» database (including such perennial
favorites as the
Common Tern and Field Sparrow) have lost at least half of their populations during that p
Common Tern and Field Sparrow) have lost at least half of their populations during that period.