Coral recruitment and sedimentation in Asan Bay and War in the Pacific NHP, Guam
Minton D and Lundgren I. 2006. Coral recruitment and sedimentation in Asan Bay and War in the Pacific NHP, Guam
War in the Pacific NHP has over 400 hectares (1000 acres) of Indo-Pacific coral reefs within its authorized boundary. The reefs are heavily impacted by numerous terrestrial activities. Sedimentation from upland poor land management practices is one of the most significant threats to the long-term health and persistence of the park reefs. Sediments are known to adversely impact coral larvae and juveniles and can impeded successfully settlement and recruitment. Recruitment was monitored in Asan Bay along a sediment gradient using PVC plates to determine baseline levels and to investigate a possible correlation between sediment load and recruitment rate and composition. Plates were deployed for 3 month intervals for 1 year to examine temporal trends. Settlement in the park was found to be very low; only 16 recruits were collected over the course of this project, with Pocillopora sp. recruits as the most common. Recruits from the family Poritidae and Acroporidae were also collected. No correlation between recruit density and sediment collection rate was observed, but settlement patterns of recruits on plates suggested light, not sediments (directly) or predation, was the primary factor affecting settlement patterns on the reef. Low recruitment rates, coupled with lower light availability as a result of sediment loads raises significant concerns about the long-term health and persistence of the coral reefs within the park.