144 Vniversitij of Calif ontia Publications in Zoology [Vol. 16 



Report on Experiments to Determine the Distances Travelled 

 BT THE Spiny Lobster 



I personally released tagged lobsters in the following numbers at 

 the places indicated: 



Auacapa Island 46 North side boat landing 



( Prisoner 's Harbor 

 ) Frey 's Harbor 



Santa Barbara 84 



Santa Cruz Island 74 



Total 204 



The accompanying table gives a detailed account of the numbers 

 of the tags affixed at the various places, both by myself as indicated 

 above and by various co-operating fishermen who affixed 129 tags to 

 my knowledge. There were possibly a slightly larger number of 

 which I have not been notified. 



It will be seen in the tables that the maximum distance travelled 

 was 9.6 miles in 28 days' time. Another specimen traveled 6 miles 

 in 14 days, making the maximum rate of .43 miles per day. Both of 

 these were caught by the Vidovich Brothers, Slavonian fishermen 

 whom I know personally and in whom I have full confidence. The 

 tag that was carried 9.6 miles (No. 434) was one that I myself had 

 affixed. Mr. Vidovich sent it to me after recovering it. It might be 

 further stated that Japanese fishermen on Santa Cruz Island caught 

 a specimen tagged by me, that had travelled 3i/4 miles. Most of the 

 spiny lobsters travelled much shorter distances: 



Eleven travelled less than one mile in an average of 18 days. 

 Eight travelled more than one mile in an average of 27 days. 

 Of the remaining seven the records are not complete. 

 The total average distance travelled was 1.4 miles. 

 The total average time in the vpater was 22 days. 



The accompanying map (fig. 1) shows that various directions of 

 dispersal were followed from a given point. This is well illustrated 

 in the course followed by the five recovered specimens of the fifty- 

 three spiny lobsters released east of Prisoner's Harbor, on Santa Cruz 

 Island. Their directions of dispersal can be best understood by 

 reference to the map. Three went east, one went west and one re- 

 mained at the same point where it was liberated. The last-mentioned 

 had remained at the same point for sixteen days, while No. 152, released 

 at the same time and place, had travelled three and one-quarter miles 



