acornwoodpecker adaptation(biology) animals birds birdsofprey birdwatchingguides britishcolumbia britishisles californiaspottedowl congresses conservation counting ecology effectofhabitatmodificationon effectofhumanbeingson effetsdesmodificationsdel'habitatsurles endangeredspecies estimates evolution fowling galapagosislands gameandgame-birds geographicaldistribution greatbritain groundfinches grouse habitat history illinois jagd lifesciences mandarteisland maps maryland mistnetting monitoring nature northamerica northernbobwhite oiseaux ontario ornithology peregrinefalcon populationbiology populations reintroduction reproduction science songsparrow vogelfang vögel waterbirds wildlifemanagement zoology