Corals: ‘canaries’ in coastal communities?

1. Corals: ‘canaries’ in coastal communities? Misaki Takabayashi, John Burns, Narrissa Spies, Makani Gregg, Patrick Yasukawa Marine Science Department / Tropical Conservation Biology and Environmental Science University of Hawaiʻi at Hilo

2. Corals in context of ahupua‘a • Most reefs in MHI are fringing = direct contact • Corals are foundation species of reef ecosystem • Intimate relationships with humans • Sessile (stuck on seafloor) • Holobiont in delicate balance • Host with immune system

3. So, what does it mean when corals are not healthy?

4. Coral Diseases What coral diseases might indicate: “However, these studies should include comprehensive efforts to better understand the relationship between coral diseases and environmental changes, largely anthropogenic in nature, occurring on coral reefs around the world. These environmental insults are the cause of the physiological stress that subsequently leads to coral mortality and morbidity by many mechanisms including overwhelming infections by opportunistic pathogens.” (Lesser et al. 2007) When studying coral diseases: “A rigorous assessment of disease needs epizootiological data in order to have diagnostic utility. Analyzing disease morphology (gross and cellular), pathogenesis, etiology, and associated epizootiology allows for determination of the impacts a disease may have on an afflicted coral population. Considering the lack of characterization of many coral diseases to date there is a severe need to address these factors for any outbreak of lesions in coral populations.” (Burns, Rozet, Takabayashi, in review)

5. Corallivores Turner lab, UHH • How do coral disease affect corallivores? • abundance • food preference Corals (population, community) • Disease prevalence & severity affected by • species? • colony size/orientation? • population structure? • community structure? • How does disease affect • Symbiodinium photosynthesis? • coral reproduction? • skeletal density? • calcification gene expression? • vulnerability to bleaching? Coral (individual) • Disease prevalence correlated with? • terrigenous effluence? • water flow? • temperature? Water Quality Wiegner lab, UHH

6. Disease Characterization • Morphological signs • Impacts at the cellular level • Temporal changes Type A Type B

7. Assess Disease Threat • How does the disease affect organismal function? • What is the severity of the disease? • Quantify impacts to the affected population

8. Identify Drivers of Resilience Linear Regression R2=74.8 p<0.01

9. Characterizing coral health on Hawaii Island

10. Project Aims To characterize and compare……….. • Population structure • Disease prevalence 3. Severity …………….between sites on Hawaii Island.

11. 6 SitesWaiuliWaiopaeKeauhou Pohue Kailua Kaloko Honokohau NHPKahuwai

12. Methodology • 12 randomly selected 25m transects • Colonies that touch transect get surveyed • Things recorded: • Species, size, depth(m), disease sign, % or # of disease sign • Pre-measured 1m rope • Photo documentation • ERDAS Imagine 1.0