142 JJniversiiij of Califoniia Publications in Zoology [Vol. 16 



should be accepted with caution. One hear.s frequent accounts of the 

 replenishment of spiny lobster fishing-grounds within a few months 

 or a year after they have been practically fished out. Nearly all fisher- 

 m,en state that there must be considerable migrations of spiny lobsters 

 because they may sometimes find them wholly absent from a place 

 where they may later occur in plenty. Changes in the feeding con- 

 ditions may in part account for their seeking the bait more at one 

 time than at another, but I feel that such an explanation would liardly 

 account for these fluctuations in the size of the catch, and such re- 

 plenishment of localities must be considered as due to haphazard or 

 concerted migrations from without. 



Some experiments were carried out in the winter of 1911 with an 

 aim to determining the direction and extent of these movements. It 

 was decided that the region of Santa Barbara and the outlying islands 

 was especially well adapted for the carrying out of the experiment. 

 The mainland affords sixty miles of rocky coast with an almost con- 

 tinuous barrier of kelp. While Santa Barbara is not in the center 

 of this region, it is so situated as to afford an opportunity for the 

 spiny lobsters to travel long distances in each direction along a coast 

 where intensive fishing is being carried on. Santa Rosa and Santa 

 Cruz islands are about thirty and twenty-five miles distant from the 

 mainland respectively, while Anacapa is about twenty miles from 

 Ventura. Spiny lobster fishing is widely practiced in all this region 

 with the exception of Santa Rosa Island, where the owners will not 

 permit fishermen to land. At times, however, fishing operations are 

 carried on there from boats. These three islands are separated from 

 one another by channels about five miles wide. It would be possible 

 for a spiny lobster to travel between Santa Cruz and Santa Rosa 

 islands without reaching a depth greater than twenty-four fathoms 

 and between Santa Cruz and Anacapa Islands a depth of thirty- 

 three fathoms. Many of the fishermen took an intelligent interest 

 in the experiment. Among the first to respond by tagging lobsters 

 were the members of the Japanese Asahi Company on Santa Cruz 

 Island. 



I used a tag of somewhat unusual kind. It was thin and light, 

 and had stamped upon it directions sufficiently full to indicate its 

 purpose. It was thought that this would gain returns from it in the 

 unlikely event of any tagged specimens falling into the hands of 

 fishermen not instructed regarding the experiment. I made a very 

 thorough canvass of the territory covered by the experiment and per- 



