H6i 



ZOOLOGICAL SOCIETY BULLETIN 



ZOOLOGICAL SOCIETY BULLETIN 



Brpai Imrulti : 



Mammal 

 W. T. Hornadat. 

 A quarium 



C. H. TOWNSEND. 



Raymond C. Osburn. 



Reptile 

 Raymond L. Ditmars. 



Bird 

 C. William Beebe. 

 Lee S. Crandall. 



Published Bi-Monthly at the Office of the Society, 



1 1 Wall Street, New York City. 



Yearly, by Mail, 81.00 



MAILED FREE TO MEMBERS. 



Copyright, 1912, by the New York Zoological Society. 



Each author is responsible for the scientific accuracy 

 and the proof reading of his contribution. 



Elwin R. Sanborn, Editor. 



Vol. XVI. No. 51 



MAY. 1912 



THE TRAGEDY OF THE GREBES. 



Because of the almost unprecedented duration 

 and frequent occurrence of periods of very low 

 temperature, the winter of 1911-12 was an un- 

 usually severe one for those species of birds 

 which commonly pass that season with us. In 

 the vicinity of New York, conditions were some- 

 what ameliorated by the absence of deep snow, 

 but in the northern portions of the state the 

 reverse was the case. 



The Finger Lakes of central New York — 

 more especially Cayuga, Seneca and Keuka — 

 have always been a haven for great numbers of 

 water-fowl during the winter months. Large 

 flocks of ducks take advantage of the open 

 water to feed on the succulent aquatic plants, 

 crustaceans and insect larvae, and numerous 

 loons and grebes pursue the fishes which form 

 their daily fare. Only at long intervals are 

 these lakes frozen over, and the birds become 

 accustomed to resorting there with confidence. 

 Induced by the unseasonable mildness of the 

 early winter, many others lingered on their 

 southward journey, so that the number of indi- 

 viduals during the past season probably was 

 even greater than usual. 



When the sudden fall in temperature came, 

 tile birds found themselves in a serious predica- 

 ment. Their feeding grounds were frozen over 

 completely or so restricted that the available 

 food was quickly devoured. As the ice en- 

 croached farther and farther and the circle of 

 open water drew closer, it seemed that starva- 

 tion must overtake the flock. At this juncture, 

 however, the State Conservation Commission 

 took a hand and the ducks were supplied daily 

 with grain. We are informed by Mr. Llewellyn 

 Legge, Chief Game Protector, that in February 

 about 5.000 ducks were being cared for in a 



space in Seneca Lake, kept open by the move- 

 ment of the water from a large spring. 



For the grebes and loons, however, this treat- 

 ment was of no avail. Strongly specialized for 

 pursuing darting fishes under water, thej 7 are 

 almost helpless when out of that element. Loons 

 are able to stand erect only upon the entire 

 tarsus and cannot rise on the wing unless a 

 good expanse of open water allows a flapping 

 start. Grebes are not at quite such a disad- 

 vantage when ashore as are loons, all of our 

 species being able to stand firmly upon the toes 

 and get about fairly well. It is probable, how- 

 ever, that they cannot rise from the land, even 

 when space offers for a running start. 



Finding themselves being closed in by the ice 

 and the food supply no longer accessible, these 

 birds, possessing, perhaps, more initiative than 

 the ducks, took wing while still able to do so 

 and started on a search for open water. As 

 might be expected, the flight was in a southern or 

 south-easterly direction. The loons seem to have 

 succeeded fairly well in reaching some haven, 

 only one instance of disaster having come to 

 the notice of the writer. This bird, reported as 

 a Red-throated Loon (Gavia stellata), was 

 stranded near Utica and died shortly after a 

 game warden had chopped it out of the ice from 

 which it had been unable to extricate itself. 

 This unfortunate ending may have been hastened 

 by the well-meaning but misguided warden, who 

 placed the bird in a warm bath and supplied 

 it with canned salmon ! 



The grebes, however, were less fortunate. 

 Weakened by lack of food, and, no doubt, be- 

 wildered by the apparent absence of their 

 natural element, they dropped wherever fatigue 

 overtook them. Floundering in the deep snow, 

 the miserable birds must have perished in great 

 numbers. Many doubtless fell prey to foxes and 

 other predacious creatures. Between February 

 11 and 28, 1912, no less than thirteen Holboell 

 Grebes (Colymbus holboelli) , shipped from 

 Syracuse, Canajoharie and Rhinebeek, arrived at 

 the Zoological Park, all considerably the worse 

 for their experience. 



When one considers the widely separated lo- 

 calities and the slimness of the chance that any 

 individual bird would drop near a road or in 

 some other place sufficiently travelled for the 

 waif to be discovered, it is not difficult to be- 

 lieve that the number of those which died un- 

 found must have been large indeed. 



This instance forms an excellent example of 

 the effect of natural conditions on the fluctuating 

 status of species. For a bird of more concen- 

 trated distribution than that of this grebe, a 



