Gorgonian Biogeography in the Indo-Pacific: An Understudied Mecca of Biodiversity Gorgonian Corals: Definition & Importance Methodology Gorgonian distributions were compiled layers were projected into the World Gorgonians (Cnidaria: Anthozoa: Octo- tion, and extreme sea surface tempera- and synthesized using databases provided Winkel Tripel NGS with a central meridi- corallia) are an extremely widespread, tures. The Center of Refuge hypothesis by author S. Rowley (unpublished) and an of 156.000. Shallow (0-29m) and diverse, and charismatic group of soft posits that due to its thermally benign two museums, courtesy of the Smithson- mesophotic (30-200m) zones were com- corals comprised of over 100 genera in and stable environment, the mesophotic ian Institute and the Bernice Pauahi Bish- pared and count tables based on the fami- 23 families. zone is a center of refuge for Indo- op Museum. Decimal degree locations lies were created for the whole sample They can be Pacific biodiversity and that these inter- were entered into ArcGIS10.1 and the and sub-regions. found at all mediate depths may serve as nurseries, depths and all and sources/sinks of larval recruits for over the world. many marine organisms including gorgo- In addition to nians. However, despite its apparent im- their staggering portance, very little research has been biodiversity, conducted in the mesophotic zone due to gorgonians are limited technology and expenses. also an integral component of Figure 1. Melithaea sp. found in SE Sulawesi. The Indo-Pacific and the Coral Triangle reef ecosystems is a region encompassing Indonesia, Ma- increasing habitat complexity and there- laysia, Papua New Guinea, the Philip- fore reef biodiversity by providing pro- pines, Ti- tection, food, and shelter for other marine mor Leste, benthic organisms. Given their essential and the role in these ecosystems and their wide Solomon distribution, gorgonians make useful in- Islands, dicators of reef health, and are a growing and is area of ecological research. generally consid- Recent research and anecdotal evidence Figure 2. Illustration of the Indo-West Pacific with the ered the boundary of the Coral Triangle. Red shading represents has shown that biodiversity and abun- distribution of coral reefs in this region. global ep- dance of gorgonians increases with depth icenter of Figure 4. Gorgonian biodiversity within the Indo-Pacific and Coral Triangle based on scientific family, using museum and field specimen collections (n = 4,763). as habitats transition from shallow-water marine biodiversity. However, to mesophotic reefs. Biodiversity on knowledge of species distributions, pop- Results Graphs comparing the biodiversity be- mesophotic reefs is exceptionally high ulation dynamics, and diversity in this ar- tween shallow and mesophotic zones compared to that of shallow-water, with ea, especially in regards to gorgonians, showed regional variation within the Indo communities comprised of zooxanthel- are extremely lacking compared with -Pacific. In the Philippines, mesophotic late corals, azooxanthellate scleractinian other locations such as the Caribbean. gorgonians appear to be more abundant and black corals, This region is also than shallow gorgonians, whereas in SE macroalgae, and threatened by cli- Sulawesi the shallow gorgonians were sponges, as well as mate change and an- more abundant. The mesophotic and shal- their associated thropogenic impacts. low gorgonian abundances appear to be microbial commu- Further understand- similar in the Ryuku Islands. These differ- nities. ing and research is ences are most likely attributed to sam- pling, but the abundance of mesophotic needed in order to gorgonians in the Philippines provides ev- These coral-reef preserve not only the Figure 5. Representation of gorgonian biodiversity in the Indo-Pacific by family. Number biodiversity, but also represents total count of individuals followed by percentage of total gorgonian speci- idence for the hypothesis that gorgonians ecosystems are mens. grow more abundant at greater depths. found from 30m to the economic ser- 200m and are char- vices provided by these resources to acterized by steep Figure 3. Global distribution of gorgonian corals based on museum and field speci- light gradients, men collections. the surrounding high levels of nutrients and particulate communities. organic material delivered by upwelling and internal wave action, and lower tem- Using gorgonian museum specimen and peratures. Importantly, they are protected field collection data from the Coral Tri- from stressors created by destructive angle, I test whether gorgonian coral di- wave and storm energy, high UV radia- versity increases with depth. Conclusions and Implications for the Future Despite regional variation, the overall cruits for a wide variety of organisms, in- depiction of gorgonian distribution in the cluding gorgonians. This knowledge will Indo-Pacific clearly demonstrates not on- be essential in developing conservation ly the incredible breadth of these charis- strategies to preserve ecosystems in the matic animals, but also the need for fur- face of rapid climate change and destruc- ther research regarding the mechanisms tive anthropogenic impacts. Additionally, behind gorgonian biodiversity. Surpris- this project highlights the importance of ingly little research has been conducted museum collections, which provide key on gorgonians within the Indo-West Pa- insight, inspiring new research questions. cific and Coral Triangle, despite their Results from this project suggest that fur- Figure 6. Shallow-water and mesophotic gorgonian biodiversity examined by sub-region. known enormous presence, and even less ther research should encourage greater References Kahng, S.E., Garcia-Sais, J.R., Spalding, H.L., Brokovich, E., Wagner, D., Weil, E., Hinderstein, L., Toonen, R.J. 2010. research has been conducted in the meso- sampling effort and the examination of Cartographer Charlee Corra Community ecology of mesophotic coral reef ecosystems. Coral Reefs. 29: 255-275. Kinzie, R.A. 1974. Plexaura homomalla: the biology and ecology of a harvestable marine resource. Prostaglandins Date 29 April 2013 from Plexaura homomalla: Ecology, Utilization and Conservation of a Major Medical Marine Resource A Symposium. photic zone. Financing further research sub-zones within mesophotic reefs to in- 22-38. Course Intro to GIS Lesser, M.P., Slattery, M., Leichter, J.J. 2009. Ecology of mesophotic coral reefs. Journal of Experimental Marine will be integral to a better understanding vestigate at which depths gorgonians be- Professor Carl Zimmerman Biology and Ecology. 375:1-8. Mora, C., Chittaro, P.M., Sale, P.F., Kritzer, J.P., Ludsin, S.A. 2003. Patterns and processes in reef fish diversity. Na- TA Carolyn Talmadge ture. 42: 933-936. of the role of mesophotic reefs as refugia come the dominant presence in meso- Projection World Winkel Tripel NGS Olson, J.B., Kellogg, C.A. 2010. Microbial ecology of corals, sponges, and algae in mesophotic coral environments. FEMS: Microbial Ecology. 73:17-30. Data Sources Gorgonian distribution data courtesy of the Smithsonian and sources of shallow water larval re- photic coral ecosystems. Sanciangco, J.C., Carpenter, K.E., Etnoyer, P.J., Moretzsohn, F. 2013. Habitat availability and heterogeneity and the Institute, the Bernice Pauahi Bishop Museum, and Sonia Rowley Indo-Pacific warm pool as predictors of marine species richness in the tropical Indo-Pacific. PLOS One. 8(2): 1-18. (unpublished data), Coral Triangle Atlas (ctatlas.com) .