...The birds were venturing forth from their retreats in order to wing their way among the crows croaking wrathfully above the closed tombs... 
Vicente Blasco Ibanez Charlotte Brewster Jordan 「The Four Horsemen of the Apocalypse」
...A high whistling made by wings inflight, probably also a low croaking as in No...
Frank M. Chapman 「Color Key to North American Birds」
...During the monsoon the silence of the night is broken onlyby the sound of falling raindrops, or the croaking of the frogs,the stridulation of crickets innumerable, and the owlet's feeblecall...
Douglas Dewar 「A Bird Calendar for Northern India」
...For inNovember the ten might have been fourtimes ten fat and lusty, lazy fellows,boring the oozy margins of these samepools where the frogs are croaking andthe toads are singing to-day...
Rowland E. Robinson 「In New England Fields and Woods」
...I had seen a great blue heron sailcroaking, croaking, into an arm of the big pond where I was catchingbullpouts, and crept down through dense woods to find out what he wascroaking about...
William J. Long 「Wood Folk at School」
...Itwas hoarse and harsh and croaking...
Various 「Astounding Stories of Super-Science July 1930」
...We no longer heard the discordant shriek ofthe parrots, or the hoarse croaking note of the bittern...
Charles Sturt 「Expedition into Central Australia」
...These noisy birds(Plyctolophus Leadbeaterii) kept incessantly screeching to their young,which answered them in notes that resembled the croaking of frogs, morethan anything else...
Charles Sturt 「Expedition into Central Australia」
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