266 THE PLAGUE OF OCTOPUS ON THE SOUTH COAST, 



manner the enormity of the damage which has been inflicted on the 

 shell fisheries of the Devon and Cornish coasts during the past summer. 

 Although they mark probably the climax of the plague so far as 

 Plymouth is concerned, yet destruction on a similar scale took place for 

 at least six weeks or two months previously, and on a scale not much 

 less serious during the earlier months of the year. 



One of the most remarkable phenomena connected with the plague 

 of octopus at Plymouth took place early in September, and appears to 

 indicate that the octopus were moving about in large marauding bands. 

 On Sunday, September 8th, it became known that crabs of unusual size 

 were to be found between tidemarks at Batten and other parts of the 

 eastern side of the harbour, and more than a hundred crabs, 5 to 

 7 inches in breadth, were picked up in that locality in the single day, as 

 well as larger numbers of the smaller size which normally frequent the 

 tidal zone.* 



During the next few days crabs of 4-6 inches breadth were also 

 exceptionally abundant on the shore below the Hoe, near the bathing- 

 place at Tinside, and were gathered by boys who took them away by 

 dozens at a time. 



On the western shore, under Mount Edgcumbe, near the " Bridge," 

 we found no specimens exceeding 4 inches in breadth. 



The explanation of the appearance between tidemarks of such 

 exceptional numbers of fair-sized crabs is probably that the hordes 

 of octopus had driven the crabs inshore to the shallowest margins as 

 the only avenue of escape. The suddenness of the phenomenon, and 

 its limitation to the eastern and northern sides of the harbour, was 

 possibly due to an incursion into the Sound, through the eastern 

 channel, of roving bands of octopus in search of food, though it is 

 not improbable that the shallower declivity of the bottom and the 

 greater extent of the tidal zone in this region may have facilitated 

 the escape of a larger number of crabs in this part than elsewhere in 

 the Sound. 



In order to measure the general damage done to the shell-fish 

 industry on the South Coast during the year, I have had recourse to 

 the Board of Trade's monthly statistics of fish landed. As the practical 

 problems presented are of an immediate character, I have thought it 

 better not to wait until the whole year's returns have been completed, 

 but to base comparisons on the statistics for the six summer months 

 alone during the present and preceding years. 



* Mr. W. Demelwick, water bailill', informs me that from the above-mentioned date to 

 the end of October at least 600 crabs and lobsters were jncked up in this locality, viz. 

 about 200 male crabs, 4-7 inches broad ; 300 female crabs, 3^-6^ inches broad ; and 100 

 lobsters, 9-11 inches in length. He adds, "The occurrence was most unusual, and no 

 one remembers such a thing before." 



