1048 



ZOOLOGICAL SOCIETY BULLETIN 



ZOOLOGICAL SOCIETY BULLETIN 



Mammals 



W. T. HoRNADAY. 



Brpartmrnta : 



Reptiles 

 Raymond L. Ditmaks 



Birds 

 C. William Beebe. 

 Lee S. Cbandai.l. 



Aquarium 



C. H. TOWNSEND. 



Raymond C. Osbl'hn 



Published bi-monthly at the Office of the Society. 

 11 Wall Street, New York City. 



Yearly by Mail, $1.00. 



MAILED FREE TO MEMBERS. 



Copyright, 1913, by the Netv 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. 60. 



NOVEMBER, 1913 



killed after much use of the harpoon and the 

 firing-of innumerable bullets. An ordinary 

 whaling ship, of course, would have disposed 

 of it in .short order. 



The smaller photograph was kindly fur- 

 nished by Mr. Joseph N. Beck of Long Kev, 

 Florida, ' 



DESTRUCTION OF FISHES BY ALG^ 



It is well known fact that in midsummer 

 there arc often great losses of fish life in small 

 lakes and ponds. This is due to the presence 

 of microscopic algae, which gradually become 

 so abundant as to discolor the water. During 

 the time when the temperature of the water 

 is highest, generally in August, this minute 

 plant life reaches its maturity and this period 

 is often followed by the death of fishes in 

 large numbers. 



The algae are of several genera and thrive 

 best in still waters. When abundant they 

 give the water a greenish tone which intensi- 

 fies as the summer advances. When the 

 plant cells mature the water becomes foul 

 through the exhaustion of its oxygen and fish 

 life is endangered. The odor from the ponds 

 caused by decaying algae, may be so bad as 

 to be noticeable some distance away. When 

 this happens in reservoirs the water may 

 become almost unfit for use. 



Artificial ponds of shallow depth and little 

 flow of water are particularly susceptible to 

 discoloration by algae in summer. This is 

 especially true of foul ponds where there may 

 be considerable decaying vegetable matter 

 upon the bottom. When small lakes, ponds 

 and reservoirs are at the height of discolora- 

 tion on account of algae, they are commonly 

 said to be "blooming" or "working." The 



rapid and often serious destruction of fish 

 life in connection with this condition of the 

 water is of common occurrence. In Wee- 

 quahic Lake in one of the parks of Newark, 

 N. J., a few years ago, fishes of several species 

 died and were washed ashore by the cartload, 

 This artificial lake being simply a flooded 

 marsh was especially adapted to the develop- 

 ment of algae, the matted plant life of the 

 marsh having been left to decay when it was 

 submerged. 



The Commissioner of Parks of New York 

 informed the writer of a great loss of fish life 

 in August in the Central Park lake known as 

 Harlem Meer. There is but little flow of 

 water in the park lakes of New York City 

 and they are all subject to discoloration by 

 algae in summer. A strong flow in any of 

 them would soon improve conditions and the 

 same is true of the Newark lake referred to. 



The development of algae can be controlled 

 by the use of copper sulphate without injury 

 to fish life, and the Commissioner has been 

 advised to begin checking it early in July, 

 and to remove by any means possible, the 

 excessive growth of the coarser water plants 

 with which these lakes abound. 



THE SEA TURTLE IN THE COURTS 



The suit brought by the Humane Society 

 in New York City some months ago against 

 a local shipper of sea turtles on a charge of 

 cruelty to animals, was dismissed by the 

 judge, the jury having failed to agree. It 

 was a test case and there were numerous 

 witnesses on both sides, among them the 

 director of the Aquarium. The substance of 

 Dr. Townsend's testimony was as follows: 



The marine turtle industry in the eastern 

 states amounts to something like $150,000 

 annually. It is therefore an important 

 business and yields a large supply of highly 

 desirable sea food. It is necessary that the 

 animals captured in tropical waters be brought 

 into the northern markets alive and in good 

 condition. That they are in good condition 

 after shipment is proved by the fact that 

 when placed in the floating cars of the New 

 York importers they begin feeding at once; 

 also by the fact that very large and heavy 

 turtles thus secured for the New York 

 Aquarium many years ago, when the methods 

 of shipment were not so careful as they are 

 at present, arrived in good condition, 



