November 4, 2020

10:00am Zoom Webinar

Greta Aeby
Qatar University

" Outbreak of stony coral tissue loss disease along the Florida Reef Tract: insights into investigative approach and disease ecology "

An outbreak of acute tissue disease was first discovered on reefs in the Miami-Dade region of Florida in 2014 and by 2017 had spread to other Florida regions.  Disease signs vary among affected coral species with differences in rates of tissue loss (acute and subacute), lesion morphology (adjacent bleached zone or not) and lesion occurrence (focal and multi-focal). For our first study, we examined the virulence, transmission dynamics and response to antibiotic treatment of coral species exhibiting different types of tissue loss lesions from two regions in Florida. Corals (multiple species) from both regions (Ft. Lauderdale & Middle Keys) showed progressive tissue loss but the in situ rate of mortality was significantly higher in tagged colonies in the Keys. Aquaria studies showed disease transmission occurred through direct contact and through the water column for corals from both regions but transmission success differed between species. Transmission success was higher for corals with acute (Keys) vs. subacute (Ft. Lauderdale) lesions.  Diseased fragments of all species tested responded to antibiotic treatment with a cessation or slowing of the disease lesions suggesting that bacteria are involved in disease progression.  Our 2^nd study explored potential reasons for the regional differences in disease virulence.  Disease emergence depends on a complex relationship among host, pathogen and environment which is challenging to untangle.

 

Wednesday, November 4, 2020

*10am

Via Zoom

Host: Ashlyn Ford