McGill University
M.Sc. candidate
Supervisor: Andrew Gonzalez
Hector M. Guzman
Start: 2009-06-01
End: 2012-02-20

Project

Community ecology of soft corals
Octocorals (Alcyonacea) are sessile marine foundation species common in very active environments in the Tropical Eastern Pacific (TEP). Although they are a dominant part of the community and have strong interspecific relationships, there have been very few studies of their biology and ecology. This thesis is the first attempt to study the basic biology and community structure of shallow water octocorals present in Coiba National Park in Pacific Panama, a hotspot for species richness and endemism in the TEP. The first chapter reviews the existing scientific literature on octocorals in the TEP and compares this literature to studies in other regions. This Chapter demonstrates the lack of research on these ecologically important communities and suggests future studies. Chapter 2 studies basic population dynamics (recruitment, mortality, and survivorship rates) for 15 shallow water octocoral species in 6 genera, the growth rate of 4 species of different genera, and identifies « r » and « k » selected species. Chapter 2 also reports a significant natural population decline in all study sites. Chapter 3 presents an analysis of the structure of four octocoral communities. This Chapter uses different community ecological descriptors (Rényi diversity profiles, Rank Abundance Distribution Plots (RAD), Abundance Spectrums, and ordination analysis of similarities) to evaluate changes in community structure during the population decline reported in Chapter 2 or after a punctuated anthropogenic disturbance. The population decline was not found to have changed the structure of the community, however, different recovery trajectories were observed after the disturbance. RAD and Rényi plots described the trend of the change, ordination analysis of similarities described the extent of the change, and abundance spectrums described the nature of the change.

Publications

1- Survival, growth, and recruitment of octocoral species (Coelenterata: Octocorallia) in Coiba National Park, Pacific Panama
Gomez, Catalina G, Hector M Guzman, Andrew Gonzalez, Odalisca Breedy
2014 Bulletin of Marine Science

2- Population decline and the effects of disturbances on the structure and recovery of octocoral communities (Coelenterata: Octocorallia) in Pacific Panama
Gomez, Catalina G., Hector M. Guzman, Andrew Gonzalez
2014 Journal of the Marine Biological Association of the United Kingdom

3- Potential vessel collisions with Southern Hemisphere humpback whales wintering off Pacific Panama
Guzman, Hector M., Catalina G. Gomez, Carlos A. Guevara, Lars Kleivane
2012 Marine Mammal Science