Coral Cover and Colony Count of Porites lobata at Devil's Crown, Galapagos Islands, Ecuador
Abstract
The reef-building mounding coral (Porites lobata) forms structures throughout the Galápagos Islands that provide habitat for numerous benthic marine species. Galápagos corals are impacted by aperiodic El Niño-Southern Oscillation (ENSO) events that raise ambient water temperature and can cause massmortalities. This study focuses on an aggregation of Porites lobata located in Devil’s Crown, Floreana Island using data collected from 1993-2019. Over the 26-year period, the aggregation was impacted by El Niño events in 1992-93 and 1997-98 both of which left most of the colonies bleached (loss of zooxanthellae) but without mortality. Colonies recovered over several years following each event. This study quantifies live tissue area, maximum diameters, and colony count of the P. lobata corals present at the site in 2019. An additional 10 colonies were observed in 2019 (compared to 17 in 2011), most of them small (<0.40 m2 live tissue area, n=27). Colonies ranged in size from 0.02 m2 to 1.21 m2 , with an average size of 0.36 m2 . Since 2011, live tissue area decreased from 6.92 m2 to 4.91 m2 in the 10 most studied colonies, primarily due to the death of one of these colonies. The results from this study, in addition to prior observations dating back to the late 1970s, document the long term (>44 y) resilience of this Porites lobata aggregation. Porites’ persistence despite ENSO impacts suggests this species will continue to contribute to ecosystem complexity at Devil’s Crown in the future.
Faculty Sponsors
Dr. Joshua Feingold
Project Type
Event
Location
Alvin Sherman Library
Start Date
4-6-2021 12:00 PM
End Date
4-9-2021 12:00 PM
Coral Cover and Colony Count of Porites lobata at Devil's Crown, Galapagos Islands, Ecuador
Alvin Sherman Library
The reef-building mounding coral (Porites lobata) forms structures throughout the Galápagos Islands that provide habitat for numerous benthic marine species. Galápagos corals are impacted by aperiodic El Niño-Southern Oscillation (ENSO) events that raise ambient water temperature and can cause massmortalities. This study focuses on an aggregation of Porites lobata located in Devil’s Crown, Floreana Island using data collected from 1993-2019. Over the 26-year period, the aggregation was impacted by El Niño events in 1992-93 and 1997-98 both of which left most of the colonies bleached (loss of zooxanthellae) but without mortality. Colonies recovered over several years following each event. This study quantifies live tissue area, maximum diameters, and colony count of the P. lobata corals present at the site in 2019. An additional 10 colonies were observed in 2019 (compared to 17 in 2011), most of them small (<0.40 m2 live tissue area, n=27). Colonies ranged in size from 0.02 m2 to 1.21 m2 , with an average size of 0.36 m2 . Since 2011, live tissue area decreased from 6.92 m2 to 4.91 m2 in the 10 most studied colonies, primarily due to the death of one of these colonies. The results from this study, in addition to prior observations dating back to the late 1970s, document the long term (>44 y) resilience of this Porites lobata aggregation. Porites’ persistence despite ENSO impacts suggests this species will continue to contribute to ecosystem complexity at Devil’s Crown in the future.
