Appointed to the academic staff of University College Dublin in 1968, Declan Murray took early retirement as Senior Lecturer in Zoology in 2002. His specialist interest is surface water quality monitoring and assessment by bio-indicators and sediment analyses of lakes. He is a world authority on the macroinvertebrate bioindicator group Chironomidae and has participated in pan-national taxonomic revisions resulting in now standard reference work publications.

His extensive foreign research has involved Institutes in Europe and in Japan, New Zealand, Tasmania and Western Australia. He has special interest in the aquatic fauna of oceanic islands and has worked on Tahiti and the Cook Islands as well as on Atlantic islands - Iceland, Azores, Madeira, Canary Islands and Cape Verde. He led studies on a broad range of environmental topics for European (EU DG XII), State and semi-State bodies, Local Authorities and conservation groups.

He pioneered use of palaeolimnology in Ireland, to detect trends in trophic state of lakes by analyses of short sediment cores. Most recently his team has been involved in core analyses in Loughs Arrow, Carrowmore, Gill, the Shannon lakes and L. Leane