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The Plague of Octopus on the South Coast, and its 

 effect on the Crab and Lobster Fisheries. 



By 

 Walter Garstang, M.A. 



Naturalist in charge of Fishery Investigations under the Marine Biological Association. 



Until the spring of 1899 the true or common octopus {Octopus vulgaris, L.) 

 had been comparatively rare in the neighbourhood of Plymouth during 

 the past ten or twelve years — i.e. since the opening of the Plymouth 

 Laboratory in 1888. Specimens could only be obtained for the aquarium 

 at long intervals, in spite of the tempting inducements offered to fisher- 

 men. As much as ten shillings has more than once been given to 

 fishermen for a specimen of this voracious mollusk. On the other 

 hand, the smaller and less powerful octopod known as Eledone cirrosa 

 was almost always obtainable, and the octopus tank in the aquarium 

 was rarely devoid of several specimens. 



In the early part of last year (1899) the situation began to change, 

 and we were for the first time able to keep the tank supplied with a 

 number of true octopus, since which date there has been no difficulty 

 in procuring an unlimited number of specimens, either from the 

 professional fishermen or in the ordinary course of our own fishing 

 operations. 



We noticed this increase in the abundance of octopus before there 

 was any means of judging whether it was a purely local phenomenon, 

 or was observable over a wider area. The first specimens were brought 

 to us in January, and from May onwards they were obtained in increasing 

 abundance. Early in the same year, however (though I have no exact 

 record of the date), a visitor from the Channel Islands informed me 

 that the increase of octopus in those islands was so great as to have 

 already caused much damage to the shell fisheries there, since the octopus 

 entered the pots of the fishermen, and destroyed the crabs and lobsters 

 which had been caught. 



Later in the year paragraphs began to appear in the newspapers upon 

 the subject, and during the present year (1900) have revealed that the 



