Bird migration evidence. Seabirds fly low over water but gain altitude when crossing land, and the reverse pattern is seen in landbirds. However most bird migration is in the range of . Bird strike aviation records from the United States show most collisions occur below and almost none above . Bird migration is not limited to birds that can fly. Most species of penguin (Spheniscidae) migrate by swimming. These routes can cover over . Dusky grouse "Dendragapus obscurus" perform altitudinal migration mostly by walking. Emus "Dromaius novaehollandiae" in Australia have been observed to undertake long-distance movements on foot during droughts. While participating
What Bird is That? to the League for £300. The book was extolled fulsomely by S.R. Thomas, of the NSW Department of Education, as follows; ""What Bird is That?" is the most comprehensive and informative bird book published in the Commonwealth – if not in the world. The coloured plates are a triumph not only of the genius and imagination of the artist – our own Neville Cayley on whom has fallen so fittingly the mantle of his famous father – but also of the block-maker’s and printer’s art. The publishers have done nothing finer of its kind. The life-like portrayals of our feathered