This document provides information for a datathon challenge focused on analyzing satellite, environmental, biological and socioeconomic data related to fisheries, aquaculture, and marine spatial planning. Participants are instructed to choose a challenge, use available datasets and tools listed on websites provided, and present either an idea exploiting the data or an ICT solution. A virtual research environment called the "Blue Datathon VRE" provides datasets and services for topics like species data, data analytics, geospatial data visualization, and more.