ASKAP HI imaging of the galaxy group IC 1459

We present HI imaging of the galaxy group IC 1459 carried out with six antennas of the Australian Square Kilometre Array Pathfinder equipped with phased-array feeds. We detect and resolve HI in 11 galaxies down to a column density of similar to 10(20) cm(-2) inside a similar to 6 deg(2) field and with a resolution of similar to 1 arcmin on the sky and similar to 8 km s(-1) in velocity. We present HI images, velocity fields and integrated spectra of all detections, and highlight the discovery of three HI clouds - two in the proximity of the galaxy IC 5270 and one close to NGC 7418. Each cloud has an HI mass of similar to 10(9) M-circle dot and accounts for similar to 15 per cent of the HI associated with its host galaxy. Available images at ultraviolet, optical and infrared wavelengths do not reveal any clear stellar counterpart of any of the clouds, suggesting that they are not gas-rich dwarf neighbours of IC 5270 and NGC 7418. Using Parkes data, we find evidence of additional extended, low-column-density HI emission around IC 5270, indicating that the clouds are the tip of the iceberg of a larger system of gas surrounding this galaxy. This result adds to the body of evidence on the presence of intragroup gas within the IC 1459 group. Altogether, the HI found outside galaxies in this group amounts to several times 10(9) M-circle dot, at least 10 per cent of the HI contained inside galaxies. This suggests a substantial flow of gas in and out of galaxies during the several billion years of the group's evolution.