BERMUDA

Biodiversity of Coral Reefs

PAGE INDEX

 

EAS class site

Index: Jana   

 

Bermuda Index

Question

Abstract

Introduction  

Methods

Results

Discussion 

Conclusion 

Literature Cited

Results

Location Differences by Individual Taxonomic Groups

General Methods

I ran a one-way ANOVA in JMP for each coral taxonomic group that was identified, comparing the distributions at John Smith's, Whalebone, and the Causeway.  If the results were significant (f < or = .005) I ran another test, Tukey Kramer, to determine which locations were responsible for the difference.    

 

Hard Corals

The mustard coral did not vary between locations (ANOVA, Tukey F = .255), while the brain corals did.  In all cases D. strigosa and P. astreoides made up most of the hard coral assemblage, with D. labrynthiformis comprising a small portion of the population.  D. strigosa was found in a statistically significant lower density at the causeway (ANOVA, Tukey F = .0002), while D. labrinthiformis was in higher density at John Smith's Bay (ANOVA, Tukey F = .0012).  While not quantified, it was noticed that the D. labrynthiformis had no large individuals, and most were smaller, younger, then the D. strigosa at every site.  The ANOVA information, graphical depiction, and explanations can be seen in the link above.

Hard Corals - in depth tables

 

 

 

Soft Corals

 

 

Gorgonia vantalina (sea fan) was not present at John Smiths, and was not different in number between the two other sites (ANOVA, Tukey F = .039).  There was more of the Plexaurella sp. (common sea rod) in both John Smith and Whalebone then at the Causeway (ANOVA, Tukey, F = .0001).  Briareum asbestinum (Corky Sea fingers) were found to have no variation between the three main locations (ANOVA, Tukey, F = .054).    

 Soft Corals -  in depth tables

 

  J.S. W.B. C.
D. strigosa 
D. Labyrinthiformis
Porites astreoides
Gorgonia vantalina  ----------------
Plexaurella
Briareum asbestinum
Sum vector ↑↑↑ ↑↑ ↓↓

 

 

 

Location Differences in Overall Biodiversity

 

The Shannon evenness index for both John Smith’s Bay and Whalebone Bay was high, indicating species richness and evenness, while the index value at the Castle Harbor Causeway was much lower.  (SHEI; JS 0.82, WB .84, C .28).

 

The Shannon evenness index was conducted for both North Rock and Wells Bay based on their approximated percent cover data.  Both locations had high values for evenness and richness (SHEI; NR .93, Wells .82).  North rock has a higher index value then Wells Bay, it also has a higher value then John Smith or Whalebone bay, but this may be misleading as the data is less exact.

 

SHEI and Physical Parameters at Each Site
  John Smith's Bay Whalebone Bay Castle Harbor: Causeway North Rock Castle Harbor: Wells Bay
Water Depth (4) (2) (1) (5) (3)
.75 - 4.5 m  .8 - 2 m  .25 - 1 m 2.4 - 6 m  2 - 3.5 m
Wave Action 4 3 1 5 2
Pollution 0 0 1 0 1
Natural Disturbance: Hurricane 1 0 0 0 0
Disease BBD        
Richness 5 7 6 6 7
SHEI 0.823 0.764 0.451 0.931 0.816

SHEI by location, with Physical Parameters marked