11th ICRS Abstract book - Nova Southeastern University

7.174
Coral Disease Prevalence and Dynamics in the Wakatobi Marine National Park,
South-East Sulawesi, Indonesia
Jessica HAAPKYLA* 1 , Adrian S. SEYMOUR 2 , David SMITH 3
1 School of Marine Biology and Aquaculture, James Cook University, Townsville,
Australia, 2 Operation Wallacea, Spilsby, United Kingdom, 3 Coral Reef Research Unit,
University of Essex, Colchester, United Kingdom
A study on coral diseases was conducted in 2005 and 2007 in the Wakatobi Marine
National Park (WMNP), South-East Sulawesi. This first study on coral diseases in the
area aimed to investigate coral disease prevalence and coral health in this remote area
situated in the center of the world’s biodiversity hotspot.
Three replicates of 20x2 m belt transect were used at three reef zones at five sites across a
diversity gradient. Results indicate a decrease in disease prevalence from 0.57% in 2005
to 0.24% in 2007. In 2005, only two known syndromes occurred within the sampling
unit, white syndrome (0.42%) and tumours (0.15%). An increase in the number of
diseases was observed in 2007 but their prevalence remained very low: white syndrome
(0.14%), Porites ulcerative white spot disease (0.06%), tumours (0.03%) and black band
disease (0.01%). The most common lesions in 2005 were previously undescribed
conditions (9.7%) compared to only 0.6% in 2007. Pigmented responses, which are
thought to be a common coral stress sign decreased from 3.99% in 2005 to 2.47% in
2007. In 2007 they were significantly more common in the degraded site than in other
sites. The impact of these lesions on coral health is unknown and represents an important
area for future studies.
The results of this study highlight the low disease prevalence in the area. However, the
transect method used may have left localized disease outbreaks unnoticed. To better
understand the role of coral diseases in the area, prevalence studies in the warm season
when the water temperature is approximately 5 °C warmer should be conducted. Higher
water temperatures may increase disease prevalence and, due to climate change, coral
disease outbreaks may threaten coral populations in the future in this area.
7.176
Preliminary Results On Coral Disease Prevalence in East Africa
Mohammed MOHAMMED* 1 , Narriman JIDDAWI 1
1 Institute of Marine Sciences, University of Dar es salaam, Zanzibar, Tanzania
Coral reef ecosystems are among the most diverse and most productive in the marine
environment, being compared only with terrestrial rain forests. Besides its richness and
the benefits it provides it is increasingly becoming threatened by natural and human
induced factors. Incidences of coral bleaching caused by global warming, coral diseases
outbreaks and crown of thorn starfish infestation have increased in the last few decades,
threatening well being of reef systems. Prevalence of coral diseases have been
investigated on Bawe, Chumbe and Kizimkazi reefs in Zanzibar Island by using 2x20m
belt transect at 2-5m and 6-9m depth profiles. Preliminary results show that 83% out of
3142 coral colonies surveyed are on healthy condition. 7.4% are being smothered by
algae, 2.4% show signs that resemble ulcerative white spots disease, 1.3% has
pigmentation response.3.2% showed unknown dead band. Other diseases that were found
at very low prevalence < 1% are unusual bleaching patterns, reddish colouration patch on
Porites, black band disease, tumors, coral overgrown by corallimopharians, worms and
predation scars. Preliminary results show disease prevalence on surveyed reefs is very
low; however, long term monitoring is required over a wider area so as to have a
comprehensive knowledge of the disease prevalence in the region.
Poster Mini-Symposium 7: Diseases on Coral Reefs
7.177
Impact Of Aspergillosis On The Reproduction Of The Sea Fan Gorgonia Ventalina
Kathleen FLYNN* 1 , Ernesto WEIL 1
1 Department of Marine Science, University of Puerto Rico, Mayaguez, Lajas, Puerto Rico
There is little information on the impact of the fungal disease aspergillosis on the reproductive
biology of the sea fan Gorgonia ventalina. Histological techniques were used to assess the
normal reproductive cycle of the species and compare healthy and diseased colonies. Once a
month for twelve months, tissue samples were collected from the central area of healthy
colonies (n=17), and from the dark-purple, actively diseased area (ADA), the transition area
(TA) immediately adjacent to the ADA and the healthy looking area (HA; >10cm from ADA
and the edge) of each of five diseased colonies. Twenty polyps from each histological sample
were randomly selected and the presence of eggs and/or spermaries was noted. G. ventalina is
gonochoric and reproductive colonies were found year-round. Healthy colonies peaked in the
number of reproductive polyps from fall to early spring with male colonies peaking later than
females (G-tests, p