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AN INVASION OF BRITISH GUIANA BY LOCUSTS IN 1917.* 



By G. E. Bodkin, B.A., Dip. Agric. (Cantab.), F.Z.S., F.E.S., 

 Government Economic Biologist, British Guiana. 



WITH A COMPLETE ILLUSTRATED ACCOUNT OF THE 

 LIFE-HISTORY OF THE SPECIES. 



By L. D. Clears, Jnr., F.E.S., 

 Biological Division, Dept. Sc. & Agric, British Guiana. 



British Guiana has not been invaded by migratory locusts since the year 1886, 

 when, as far as it is possible to ascertain from the records of those bygone days, 

 the same species of locust was implicated. Also, on the occasion of this previous 

 attack, it seems very probable that a swarm first infested the North West and 

 Pomeroon areas and, multiplying there, migrated further down the coast to Berbice. 



In 1917 this further migration did not occur, and it may be fairly stated that 

 this was directly due to the energetic manner in which the destruction of the swarms 

 was prosecuted. This event, as will be described later, admirably illustrates the 

 very real value of legislation — in British Guiana at least — in dealing with outbreaks 

 of insect pests or plant diseases. Such legislation does not affect the honest and hard- 

 working farmer ; it helps him by forcing his lazy and indifferent neighbours to 

 carry out remedial measures which, if neglected, would result in the reinfestation 

 of his lands and render his previous work nugatory. 



Venezuela appears to be a centre of activity for swarms of migratory locusts, 

 and judging from reliable sources of information, nothing is ever done in that 

 country to destroy them. In consequence, Trinidad is frequently invaded by 

 swarms from the Venezuelan mainland. 



In this paper I have given a detailed account of the arrival and distribution 

 of the swarm, which is well illustrated by the accompanying map. A description 

 of the manner in which the campaign was conducted, and of the control methods 

 utilised in the various areas is also set forth. A full account of the life-history 

 has been prepared, with drawings, by Mr. L. D. Cleare, Jnr., of the Biological 

 Division. 



I have been unable to secure a generally accepted scientific determination of 

 this species. Some years ago a flight of migratory locusts visited the West Indian 

 Island of Trinidad ; specimens were brought thence by the Governor of British 

 Guiana, Sir Walter Egerton, and presented to this Division. On the occurrence 

 of the locusts here in 1917 the adults which originally came from Venezuela were 

 compared with these Trinidad specimens and they appeared similar. The Trinidad 

 specimens were determined as Schistocerca paranensis, Burm, by an American 

 authority — I am unable to say exactly by whom. Specimens from British Guiana 

 were then sent to the Imperial Bureau of Entomology, London, and were identified, 



* Published by permission of the Director of Science and Agriculture, British Guiana. 



