MEPS 367:125-131 (2008)  -  DOI: https://doi.org/10.3354/meps07600

ABSTRACT: Infection of sea fans by the fungal pathogen Aspergillus sydowii is one of the most widespread coral diseases in the Caribbean. The source of this normally terrestrial fungus in marine ecosystems is perplexing, but of interest to coral conservationists, since tracking sources of pathogens provides one of the few avenues to limit pathogen spread. Hypothesized inputs of A. sydowii include terrestrial deposits, marine sources, and African dust. Windborne dust from Africa amounts to nearly 1 × 10⁹ t yr^–1, much of which is deposited over the Caribbean region. Several studies have examined the microbiota of African dust and detected the presence of Aspergillus spp., although identifications were only to the genus level. I used specific culture conditions to determine whether this coral pathogen is present in 4 samples of airborne dust from the Caribbean and Africa, and 3 sediment samples from Africa and the Cape Verde Islands (eastern Atlantic). A diversity of fungi were found, including 7 species of Aspergillus and related taxa. However, none of the samples contained A. sydowii. The lack of A. sydowii in airborne dust and sediment samples suggests that African dust is an unlikely source of the marine pathogen A. sydowii. Given the high richness of fungi observed, even under selective growth conditions, identification of potential pathogens to the species level is critical.

KEY WORDS: Coral disease · Aspergillosis · African dust · Sahara · Long-distance transport · Sea fan disease