A lake fish survey was conducted on the Hillsborough lakes complex in September 2020 to assess the persistence of stocked glass eels and to assess the distribution and abundance of other fish species including Carp species. Across all the lakes a total of 114 European eels were recorded, 159 Tench and 867 Roach/Rudd. No Carp were caught in any of the lakes surveyed at this time, despite using the same methodology and similar timing as the surveys which recorded their presence in Hillsborough lake in both 2013 & 2018. The distribution of fish species recorded during this survey confirms the unsuitable nature for coarse fish migration as a consequence of the in stream infrastructure and the fluvial nature of the small interconnecting stream running between all 4 waterbodies. Coupled with very low catches of only a single Roach in outflowing Culcavy Pond would support the Departments assessment that there is a low risk of Carp escape to the Lagan River.