SUBTIDAL ENVIRONMENTS AND ECOLOGY 



101 



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Medren 



Enewetak 



Fig. 6 Locations of lagoon pinnacle reefs in the southeastern portion of Enewetak Atoll. Many of these pinnacles have been 

 important collection localities and are not named on any other published charts. Names used are as follows: 1. Tunnel Pinnacle. 

 2. unnamed. 3. unnamed. 4. Cucumber Patch. 5. Dead Pinnacle, 6. Pole Pinnacle, 7. unnamed, 8. unnamed. 9. unnamed, 

 10. unnamed. 11. unnamed. 12. Medren pseudopinnacle. 13. south Medren Pinnacle. 14. Reefer 8, 15. Sand Island *1, 16. Sand 

 Island *2, 17. north Enewetak Pinnacle, 18. Marine Pier Pinnacle, 19. unnamed, 20. unnamed, 21. Harry's Patch, 22. Gemini 

 Pinnacle, 23. Power Plant Pinnacle. 24. Friendly Fish (Bubblebut), 25. Mini Power Plant Pinnacle, 26. unnamed, 27. Garbage Pier 

 Pinnacle. 



Asparagopsis taxiformis is perhaps, after Halimeda 

 spp., the most common algae on pinnacle reefs {Fig. 7). Its 

 upright thalli protrude from most rocky areas, often in 

 dense stands. Schleck (MPRL, 1978) found that A. taxi- 

 formis grew in a band about 1 m wide and several hun- 

 dred meters in length along leeward island lagoon shores. 

 In deeper water, Schleck reported it formed an abundant. 



but scattered, community with a vertical distribution to at 

 least 20 to 30 m. 



The Lagoon Margin 



The lagoon between 30 m depth and 

 islands or the reef flat, the "lagoon margin," 



the shore of 

 is an area of 



