33 pages matching North America in this book
Results 1-3 of 33
What people are saying - Write a review
We haven't found any reviews in the usual places.
THE COMPARATIVE STABILITY OF POPULATIONS
THE SIGNIFICANCE OF CLUTCHSIZE IN BIRDS
23 other sections not shown
10-year cycle abundant adults Alpine Swift animals average clutch birds Blue Tit breeding season broods California Quail cause cent Chapter chicks clutch-size Coal Tit colonies Common Swift Crossbill cyclic death-rate declines deer density-dependent disease ducks emigration Europe factors feeding females figures fish fluctuations food shortage food supply further gallinaceous birds habitat hatched Hence higher increase individuals insects irruptions juveniles Kluijver Lack Lapwing large numbers larvae lemmings limit losses males mammals migration mortality natural selection nest nestling nidifugous normally North America number of breeding number of eggs number of young numbers pairs parasites passerine peak pine population density predators prey proportion raise Red Grouse regions reproductive rate ringed Robin rodents Ruffed Grouse shown similar Song Thrush song-birds Sparrow Sparrowhawk species Spotted Woodpecker Starling starvation studied suggested summer survival Swift Table territories Tinbergen usually variations various Varying Hare voles Warbler Waxwing winter woods yearlings Yellow-eyed Penguin