Investigating blotchy bass syndrome in black basses

Black basses (Micropterus spp) are enigmatic North American sportfishes that support the most economically valuable freshwater sport fishery in the United States and serve as keystone predators within aquatic ecosystems. Hyperpigmented melanistic lesions on the surface of black basses have been observed in a number of waterbodies across the country in increasing frequency. We have recently identified that this condition, blotchy bass syndrome, is associated with a novel emerging adomavirus. A coordinated biosurveillance network is necessary to understand the geographical extent, seasonality and biological threat of this viral disease to black basses.

We have recently completed laboratory work sequencing the complete genome of this new emerging adomavirus. In order to better understand the geographical distribution and temporal occurrence of this condition, this project establishes a blotchy bass syndrome biosurveillance network that includes federal and state fisheries managers across states where black basses are managed. This work will leverage partners including Bass Pro Shops & Cabela’s and plans to augment this network with the integration of a citizen science component. The incorporation of crowd sourcing to the biosurveillance effort will increase spatial and temporal coverage of the surveillance network. The crowd sourcing component will leverage anglers associated with black bass angling groups, organized fishing tournaments and other interested citizen scientists that will be managed via state partners and university affiliates.

In addition to documenting the occurrence of this disease, we plan to develop molecular diagnostic markers for this viral disease as well as minimally invasive, non-lethal sampling methods to better establish the seasonality and progression of this disease. Sampling for virus will include non-lethal sampling of skin of clinically normal and fish presenting with blotchy bass syndrome. Complete genome sequencing will be utilized to compare genomes of isolates from geographically distant locations to interrogate phylogeographic differences. In addition, metagenomic sequencing methods will be utilized on a samples to profile the microbiomes of normal and affected fishes.

Disease occurrence data will be archived in the USGS AquaDePTH database that is currently in development.