Project: Developing a model for transmission of an infectious disease of marine sponges

Description from NSF award abstract:
Diseases of marine invertebrates have been shown to be primary causes of the accelerating destruction of Caribbean coral reef systems. Diseases affecting natural populations threaten biodiversity, resilience and the ecological balance of communities, as well as the ecosystem services they provide. To date, most studies of diseases on reefs have focused on corals, however, reports of sponge diseases have also increased across the globe. On Caribbean reefs, sponges are often a dominant component of the reef biomass,and thus play an important role in the ecology of these ecosystems. The most well described disease affecting Caribbean sponges is Aplysina Red Band Syndrome (ARBS), which affects sponges of the genus Aplysina, resulting in reduced growth, tissue necrosis and breakage at the site of the lesion, particularly during storm events. Understanding how diseases emerge and are transmitted within marine ecosystems is critical for maintaining a healthy level of biodiversity, particularly if we are to gain any predictive power in a rapidly-changing environment. Testing models of disease transmission using extensive field observations and laboratory analyses will contribute to a better understanding of disease processes and developing a transmission model for ARBS requires detailed knowledge about the pathogen-host interaction and pathogen reservoirs in the environment. While a large body of information regarding the ecology and physiology of ARBS-infected sponges is available it is recognized that modeling the transmission dynamics requires a more focused and collaborative approach. This project will develop and test a model of marine disease processes that includes the role of polymicrobial infections, sources and sinks of the pathogen(s), and the ontogeny of this disease within a model host sponge species (Aplysina cauliformis).

This novel approach is a high-risk venture (i.e., a timely idea lacking requisite results) with high pay-off potential (i.e., the results will fundamentally enhance our understanding of disease transmission within marine sponges). In this respect, the proposal is appropriate for EAGER funding. The principal investigators will use modern techniques such as high throughput sequencing and incorporate these approaches as a new tools in their laboratories as well as in their undergraduate and graduate courses. Graduate and undergraduate students will also be provided with multidisciplinary hands-on research experiences and will participate in sponge disease surveys to test the newly developed transmission model. Public seminars will be presented to discuss the implications of marine diseases coral reefs and to highlight the potential utility of disease models for the effective management of marine resources. Results from the proposed research will further our knowledge of disease transmission dynamics and enhance our understanding of the role of diseases in the ecology of coral reef ecosystems.

Selected publications related to this research:
Olson JB, Thacker RW, Gochfeld DJ (2014) Molecular community profiling reveals impacts of time, space, and disease status on the bacterial community associated with the Caribbean sponge Aplysina cauliformis. FEMS Microbiology Ecology 87:268-279. doi:10.1111/1574-6941.12222

Easson CG, Slattery M, Momm HG, Olson JB, Thacker RW, Gochfeld DJ (2013) Exploring individual- to population-level impacts of disease on coral reef sponges: using spatial analysis to assess the fate, dynamics, and transmission of Aplysina Red Band Syndrome (ARBS).  PLoS One 8(11): e79976. doi:10.1371/journal.pone.0079976

Gochfeld DJ, Easson CG, Freeman CJ, Thacker RW, Olson JB (2012) Disease and nutrient enrichment as potential stressors on the Caribbean sponge Aplysina cauliformis and its bacterial symbionts.  Marine Ecology Progress Series 456:101-111. doi:10.3354/meps09716

Gochfeld DJ, Kamel HN, Olson JB, Thacker RW (2012) Trade-offs in defensive metabolite production but not ecological function in healthy and diseased sponges.  Journal of Chemical Ecology 38:451-462. doi:10.1007/s10886-012-0099-5

Gochfeld DJ, Schlöder C, Thacker RW (2007) Sponge Community Structure and Disease Prevalence on coral reefs in Bocas del Toro, Panama.  In: Custódio MR, Lõbo-Hajdu G, Hajdu E, Muricy G (eds)  Porifera Research: Biodiversity, Innovation, and Sustainability. Série Livros 28. Museu Nacional, Rio de Janeiro. Pp 335-343. URL: http://hdl.handle.net/10088/12017

Olson J, Gochfeld D, Slattery M (2006) Aplysina red band syndrome: a new threat to Caribbean sponges.  Diseases of Aquatic Organisms 71:163-168. doi:10.3354/dao071163