PEARCY ET AL.: SUBMERSIBLE OBSERVATIONS OF DEEP-REEF FISHES 



yellowtail rockfish in a school of similar-sized 

 yellowtail rockfish, all schools were comprised of 

 fish of one species, all about the same size. Ob- 

 servers in the submersible sometimes located 

 schools where echo-groups, probably caused by 

 aggregations of large schooling rockfishes, were 

 recorded by the surface vessel's echosounder. 

 The sound scatterers were often prominent as 

 spires close to topographic pinnacles or elevated 

 rocky outcrops. 



Yellowtail rockfish schools were attracted to 

 and followed the submersible on several dives. 

 On one dive, a school of 500-1000 fish stayed 

 near the submersible for over an hour. The 

 school either followed the submersible, or 

 circled when it stopped, before abruptly turning 

 away. Individual fish were usually 3—4 body 

 lengths apart and could be clearly seen with am- 

 bient light at a depth of about 100 m. When the 

 submersible lights were turned on, fish some- 

 times "flinched" but did not swim away. On an- 

 other dive, a school of several hundred yellowtail 

 rockfish were encountered while the submersi- 

 ble descended; they remained in view most of the 

 way to the bottom. At first they actively swam 

 downward, but at 100 m they passively sank, 

 oriented head-down. When the thrusters were 

 turned on, this school disappeared, but once the 

 submersible was on the bottom, the school ap- 

 proached and swam around the submersible. 



Large Near-Bottom Rockfishes 



The best example of this category is the yel- 

 loweye rockfish. Large individuals of this species 

 were seen in shallow water swimming above 

 rock or cobble. Canary and yellowtail rockfishes, 

 though more pelagic, sometimes were seen 

 singly near the bottom. Although large rockfish 

 usually were not resting on the bottom, yellow- 

 tail, splitnose (S. diploproa >30 cm), yelloweye, 

 greenspotted (S. cklorosticius), and tiger (S. 

 nigrocinctus) were observed doing so occasion- 

 ally. 



Rockfish Coloration. Splitnose rockfish some- 

 times changed color dramatically during and 

 after collection. In situ, most individuals had 

 strikingly red and white vertical bars extending 

 almost to the ventral surface, but one that was 

 chased blanched to almost all white. Another 

 (181 mm SL) that was captured had lost its 

 prominent white bars at the surface, appearing a 

 dull red overall as shown in Eschmeyer et al. 

 (1983). Straty (1987) also noted dramatic 



changes in the coloration of juvenile rockfishes in 

 sita and after they were examined at the surface. 

 The yellowtail rockfish we observed had 3-5 

 very vivid large white spots above the lateral 

 hne. These spots faded to indistinct pale spots 

 on live yellowtail brought to the surface by hook 

 and line. The white spots on rosethorn rockfish 

 were also less prominent on fish captured and 

 brought to the surface than on those seen in 

 situ. 



Fishes Collected 



In addition to several large benthic inverte- 

 brates, we collected 21 individuals and 12 species 

 of fishes using the slurp gun (Table 3). Six 

 species of rockfishes were also captured using 

 hook and line from the support vessel: yellowtail, 

 canary, yelloweye, rosethorn, gi-eenspotted, and 

 the bank (S. rufus) rockfishes. The last fish was 

 not identified from the submersible. The 

 Hparidid Careproctus melanurus was also seen 

 on several dives (but not during transects) and 

 was collected by slurp gun. 



DISCUSSION 



The diverse physical habitats encountered 

 during our dives correlated with differences in 

 the species composition and abundances of 

 fishes. Two species gi-oups were identified: one 

 primarily comprised of rockfishes in shallow 

 water on rock and cobble, and one that included 

 zoarcids, several species of flatfishes, agonids, 

 and sablefish in deep water mostly over soft sub- 

 strates. Greenstriped and splitnose rockfishes 

 and shortspine thornyheads were most common 

 over soft substrates, whereas most other scor- 

 paenids were seen most frequently in rocky habi- 

 tats in shallow water. Richards (1986) also noted 

 that greenstriped rockfish were most abundant 

 over fine-sediment habitats in the Strait of 

 Georgia, British Columbia, whereas yelloweye 

 rockfish preferred rock wall and more complex 

 habitats at shallower depths. 



Most species were broadly distributed (Table 

 2). There was much overlap in species distribu- 

 tions, and species associations were indistinct. 

 Habitat type and depth varied together, how- 

 ever, with rock habitat occurring predominantly 

 in shallow water and mud in deep water. Al- 

 though cobble habitats were identified at two 

 depths, these data were inadequate for examin- 

 ing bathymetric segregation of rockfish species 

 within habitat types, as has been documented for 



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