Evaluation data audio for the DCASE 2018 Bird Audio Detection task (Task 3). Crowdsourced dataset, UK ("warblrb10k") - a held-out set of 2,000 recordings from the same conditions as the Warblr development dataset. Remote monitoring dataset, Chernobyl ("Chernobyl") - 6,620 audio clips collected from unattended remote monitoring equipment in the Chernobyl Exclusion Zone (CEZ). This data was collected as part of the TREE (Transfer-Exposure-Effects) research project into the long-term effects of the Chernobyl accident on local ecology. The audio covers a range of birds and includes weather, large mammal and insect noise sampled across various CEZ environments, including abandoned village, grassland and forest areas. Remote monitoring night-flight calls, Poland ("PolandNFC") - 4,000 recordings from Hanna Pamuɫa's PhD project of monitoring autumn nocturnal bird migration. The recordings were collected every night, from September to November 2016 on the Baltic Sea coast, Poland, using Song Meter SM2 units with microphones mounted on 3–5 m poles. For this challenge, we use a subset derived from 15 nights with different weather conditions and background noise including wind, rain, sea noise, insect calls, human voice and deer calls.