Nova Southeastern University NSUWorks HCNSO Student Theses and Dissertations HCNSO Student Work 4-13-2016 Population Fluctuation of the Nodular Coral Psammocora stellata in the Galápagos Islands, Ecuador: An Indicator of Community Resilience and Implications for Future Management Kathryn Brown Nova Southeastern University, [email protected] Follow this and additional works at: https://nsuworks.nova.edu/occ_stuetd Part of the Marine Biology Commons, and the Oceanography and Atmospheric Sciences and Meteorology Commons Share Feedback About This Item NSUWorks Citation Kathryn Brown. 2016. Population Fluctuation of the Nodular Coral Psammocora stellata in the Galápagos Islands, Ecuador: An Indicator of Community Resilience and Implications for Future Management. Master's thesis. Nova Southeastern University. Retrieved from NSUWorks, . (405) https://nsuworks.nova.edu/occ_stuetd/405. This Thesis is brought to you by the HCNSO Student Work at NSUWorks. It has been accepted for inclusion in HCNSO Student Theses and Dissertations by an authorized administrator of NSUWorks. For more information, please contact [email protected]. HALMOS COLLEGE OF NATURAL SCIENCES AND OCEANOGRAPHY Population fluctuation of the nodular coral Psammocora stellata in the Galápagos Islands, Ecuador: an indicator of community resilience and implications for future management By Kathryn A. Brown Submitted to the Faculty of Halmos College of Natural Sciences and Oceanography in partial fulfillment of the requirements for the degree of Master of Science with a specialty in: Marine Biology Nova Southeastern University April 2016 Table of Contents Acknowledgements ............................................................................................................. 1 Abstract ............................................................................................................................... 2 Keywords ............................................................................................................................ 3 1.0 Introduction .............................................................................................................. 4 1.1 The Eastern Tropical Pacific ................................................................................ 4 1.2 Species Description ............................................................................................ 12 1.2.1 Distribution ................................................................................................. 12 1.2.2 Morphology................................................................................................. 12 1.2.3 Growth rates ................................................................................................ 14 1.2.4 Reproduction ............................................................................................... 14 1.2.5 Predation ..................................................................................................... 15 1.2.6 Depth range ................................................................................................. 16 1.2.7 Related Species ........................................................................................... 17 1.3 Resistance and Resilience .................................................................................. 19 1.4 Statement of Purpose .......................................................................................... 21 2.0 Study Area ............................................................................................................. 23 2.1 Geographic Location .......................................................................................... 23 2.2 Environmental Conditions.................................................................................. 24 2.3 Site Description .................................................................................................. 26 3.0 Materials and Methods ........................................................................................... 31 3.1 Field Work.......................................................................................................... 31 3.1.1 Snorkeling surveys ...................................................................................... 31 3.1.2 Site Dimensions .......................................................................................... 32 3.1.3 Temperature recorders ................................................................................ 32 3.1.4 Water Flow.................................................................................................. 32 3.1.5 Survey of Associated Organisms ................................................................ 33 3.1.6 Photoquadrats .............................................................................................. 33 3.2 Data Analysis ..................................................................................................... 33 3.2.1 Coral Point Count with Excel extensions (CPCe) software........................ 33 3.2.2 Statistical Analysis ...................................................................................... 34 4.0 Results .................................................................................................................... 35 4.1 Site Dimensions.................................................................................................. 35 4.2 Temperature ....................................................................................................... 42 i 4.3 Water Flow ......................................................................................................... 47 4.4 Species List ........................................................................................................ 48 4.4.1 Associated Species Behavior ...................................................................... 48 4.5 Statistical Analysis ............................................................................................. 53 4.5.1 Psammocora stellata Area Cover ............................................................... 54 4.5.2 Psammocora stellata Density ..................................................................... 56 4.5.3 Psammocora stellata Colony Size .............................................................. 58 5.0 Discussion .............................................................................................................. 60 5.1 Site Description .................................................................................................. 60 5.1.2 Depth and Light .......................................................................................... 60 5.1.3 Precipitation/Salinity/Water Flow .............................................................. 61 5.1.4 Temperature ................................................................................................ 62 5.2 Associated Species ............................................................................................. 69 5.3 Psammocora stellata Population ........................................................................ 73 5.3.1 Comparison to Other Areas/Studies............................................................ 78 5.4 Conservation and Management .......................................................................... 82 5.4.1 Resistance and Resilience ........................................................................... 83 5.4.2 Galápagos Marine Reserve ......................................................................... 84 6.0 Conclusion ............................................................................................................. 86 7.0 Literature Cited ...................................................................................................... 87 List of Figures 1 Surface currents in the eastern tropical Pacific (ESRI 2013). Note that the Panamá Current is only present from December to April.................................... 5 2 The Galápagos Islands. The star denotes the study site near Española Island (Hijmans et al. 2004). .......................................................................................... 7 3 Native range of Psammocora stellata (IUCN 2009; Hijmans et al. 2004). ....... 12 4 Colony (E1), branches (E2) and corallites (F) images of Psammocora stellata (Stefani et al. 2008b).......................................................................................... 14 5 Modifications to the taxonomic hierarchy of the Psammocora genus as described by Benzoni et al. (2007). ................................................................... 18 6 Thirty year monthly precipitation averages taken at San Cristóbal, Galápagos Islands and Tahiti, French Polynesia weather stations (NCDC 2011). .............. 25 7 Mean monthly sea surface temperatures near Xarifa from 2004-2011 (NOAA 2011). .................................................................................................................. 25 ii 8 Thirty-year monthly air temperature averages taken at San Cristóbal, Galápagos Islands weather station (NCDC 2011). ............................................................... 26 9 Aerial image of Xarifa Island indicating study site location and proximity to Española Island (ESRI 2013). ............................................................................ 27 10 Aerial image of study area indicating predominant water flow direction. Note anchorage site signifying protected side of Gardner