title: Water quality and herbivory interactively drive coral-reef recovery patterns in American Samoa.
abstract: BACKGROUND
  Compared with a wealth of information regarding coral-reef recovery patterns following major disturbances, less insight exists to explain the cause(s) of spatial variation in the recovery process.
  
  
  RESULTS
  This study quantifies the influence of herbivory and water quality upon coral reef assemblages through space and time in Tutuila, American Samoa, a Pacific high island. Widespread declines in dominant corals (Acropora and Montipora) resulted from cyclone Heta at the end of 2003, shortly after the study began. Four sites that initially had similar coral reef assemblages but differential temporal dynamics four years following the disturbance event were classified by standardized measures of 'recovery status', defined by rates of change in ecological measures that are known to be sensitive to localized stressors. Status was best predicted, interactively, by water quality and herbivory. Expanding upon temporal trends, this study examined if similar dependencies existed through space; building multiple regression models to identify linkages between similar status measures and local stressors for 17 localities around Tutuila. The results highlighted consistent, interactive interdependencies for coral reef assemblages residing upon two unique geological reef types. Finally, the predictive regression models produced at the island scale were graphically interpreted with respect to hypothesized site-specific recovery thresholds.
  
  
  CONCLUSIONS
  Cumulatively, our study purports that moving away from describing relatively well-known patterns behind recovery, and focusing upon understanding causes, improves our foundation to predict future ecological dynamics, and thus improves coral reef management.
authors.affiliation: Pacific Marine Resources Institute, Saipan, Commonwealth of the Northern Mariana Islands. peterhouk@pacmares.com
authors.forename: Peter
authors.initials: P
authors.lastname: Houk
authors.forename: Craig
authors.initials: C
authors.lastname: Musburger
authors.forename: Phil
authors.initials: P
authors.lastname: Wiles
mesh_terms: D018948:American Samoa; D000818:Animals; D037421:Anthozoa / Q000254:growth & development*; D044822:Biodiversity; D057894:Coral Reefs; D055867:Cyclonic Storms; D004784:Environmental Monitoring; D005399:Fishes / Q000254:growth & development*; D015999:Multivariate Analysis; D011157:Population Dynamics; D012044:Regression Analysis; D012623:Seawater / Q000032:analysis*