Experiments on the Behavior of Some Puget Sound 

 Shore Fishes {Blenniidae) 



Ward R, Miles, 

 Puget Sound Biological Station 



The fish, their habitat and their general behavior 



The blennies are a group of elongated more or less cylindrical fishes 

 often without scales. The Blenniidae group, composed of several genera, 

 includes many shore forms. They are known to be represented in Puget 

 Sound by 13 species (Starks, 1911), several of which were found among 

 the San Juan Islands during this study. Many of the blennies are often 

 found entirely out of water. 



Interest in the relation of behavior to shore existence led to this inves- 

 tigation. Only the distinctly shore species were used in the experiments. 

 All of the important data refer to Xiphidion mucosum and Anoplarchus 

 atropurpureus, although occasional specimens of Pholis ornatus were in- 

 cluded with the latter. 



The shore species are found chiefly along rocky, exposed shores where 

 the water approaches saturation with oxygen. They are sometimes found 

 in beds of Zostera (eelgrass) in vigorous Ulva, or in the water on sandy 

 shores, but not upon depositing shores where the rate of decomposition is 

 high. 



The three principal species studied were found in the upper Lamina- 

 rian belt, between the upper limit (1 meter above average tide) and 1 meter 

 below the lowest tide line. Those found above low water level were con- 

 fined to rocky shores, where they remained under loose stones. There 

 were often as many as 5 or 6 individuals under a stone covering 1 sq. ft., 

 and a lone blenny was rare rather than common. 



Those individuals taken at points more than 1 meter below lowest 

 tide were usually of a different species from those found higher up. Of 

 those mentioned, occasional large individuals of Xiphidion mucosum ranged 

 higher. After an unusually high tide they appeared above the Lamina- 

 rian belt. At times of small tidal difference the zone of greater abundance 

 was lower. In cases of exhaustive collection over a given area, the next 

 high tide virtu.-illy reestablished uniform distribution. In one instance, 

 reported upon good autliority, the same individual (Pholis ornatus?), 

 seemingly was rcjjeatcdly found upon a piece of kelp under experimental 

 observation. The kclj) was anchored upon a floating raft and submerged 

 at a constant depth. The blennies on the shore line seem to maintain no 



(79) 



