The focus of our research is on the surface distribution and abundance of jellyfish. We currently conduct regular ferry surveys across the Irish and Celtic seas. Such ‘jelly data’ is important as there is a concern that the abundance of jellyfish is increasing globally as a result of climate change and degradation of marine ecosystems under the pressure of human activities. In many places in the world, jellyfish blooms (a sudden, massive increase of jellyfish numbers) have already proved they can have critical socio-economic impacts e.g. clogging fishing nets, causing mass mortalities of farmed salmon, blocking the cooling water intake of power stations, and causing the closure of beaches.