invertebrate-eaters per reef was lower on the C than on the A reefs in the first 

 two censuses (July 1980) (Mann Whitney U tests; p<0.02, p< 0.058, respectively). 

 Although fewer planktivores were recorded on A than on C reefs in July and 

 November, individual C reefs were populated by more small planktivores than were 

 the A reefs in October 1980 (Mann Whitney U tests; p< 0.0001, p<0.03, p<0.05, 

 respectively) . 



TABLE 1. Numbers of individuals of major invertebrate taxa collected per piece of 

 rubble in control (natural reef) and experimental reefs (A and C reefs) in 

 January 1981 (6 months after establishment of the experimental reefs). Results of 

 a one-way classification analysis of variance (df = 2,37) are given under F value. 

 Means and standard errors (in parentheses) are based on raw data. All data were 

 tested for homogeneity of variance (Bartlett's test), and, if necessary, trans- 

 formed by In (x+1). A superscript t indicates that test results are based on 

 transformed data. Superscripts a and b indicate means that are significantly 

 different by a Student Neuman Keuls test; means with the same subscript are not 

 significantly different. 



Taxon 



Control A Reefs C Reefs F value Bartlett's 

 Reef Wall (cinderblock (rubble only) (df=2,37) Test Value 

 + rubble) 



Stomatopods 0.5(+.2) b 1.0(+.2) 1.8(+.3) a 3.31 p<0.05 4.29 N.S. 



sSps 9 7.K+1.3) 6.3(+l.l) 8.3(+.9) 0.90 N.S. 1.26 N.S. 



(nSn-alpheids S ) 10.3(+1.5) 10.7(+2.0) 10.3(+1.6) 0.02 N.S. 2.30 N.S. 



Crabs 17.9(+2.0) 12.5(+2.4) 13.7(+2.0) 1.90 N.S. 0.69 N.S. 



Peracarids 73.3(+17.5) 62.7(+13.6) 87.3(+15.2) 0.74 N.S. 0.16 N.S. 



Sipunculans 18.5(+5.8) 17.8(+4.6) 11.7(+2.5) 0.80 N.S. 5.47 N.S. 



Polychaetes 180.0(+60.7) a 55.6(+12.2) b 76.9(+16.8) ab 4.54 t pO.05 6.32 t N.S. 



Ophiuroids 4.9(+0.7) a 2.3(+0.6) b 2.1(+0.4) b 9.53 p<0.05 2.89 N.S. 



Gastropods 6.2(+0.5) 6.5(+0.9) 6.5(+0.8) 1.28 N.S. 4.87 N.S. 



Bivalves 10.5(+2.1) 9.4(+1.9) 6.8(+0.9) 0.84 t N.S. 1.30 t N.S. 



Chitons 0.2(+0.1) 0.1(+0.1) 0.K+0.1) 0.10 N.S. 1.02 N.S. 



Examination of the invertebrate fauna in the rubble from A reefs (with fish 

 predators) and C reefs (with fewer fish predators), and in naturally occurring 

 rubble from the east canyon wall adjacent to the experimental reefs (with fish 

 predators) revealed several patterns. Although the abundances of 8 of the 11 

 major revealed taxa did not differ in the 3 sets of rubble, stomatopods showed a 

 significant increase in numbers on C reefs compared to either A reefs or rubble 

 from the canyon wall (Table 1). The naturally occurring rubble from the wall con- 

 tained species of stomatopods characteristic of shallow to moderate reef habitats 

 ( Gonodactylus oerstedii , G. spinulosus , Meiosquilla schmitti ), while the experi- 

 mental rubble (A and C reefs) was inhabited by different species ( Gonodactylus sp, 

 nov., Meiosquilla sp. nov. , M. tricarinata , Pseudosquil la ciliata ). Several of 

 the latter species are generalists, occurring in grassbeds as well as rubble 



72 



