  Observations show that galaxies in galaxy clusters are strongly influenced by
their environment. There is growing evidence that some galaxies in groups show
similar properties to galaxies in clusters, such as redder colours and gas
deficiency, highlighting that environmental processes are also effective on
galaxy group scales. The question is though, which mechanisms are important in
low density environments? To answer this, we identify gas deficient galaxies to
investigate recent or ongoing environmental processes, such as gas stripping.
We are using scaling relations between the neutral hydrogen (HI) content and
optical properties of galaxies to identify galaxies with significantly less HI
than an average galaxy of the same type. We derive new, multi wavelength
HI-optical scaling relations using the HI Parkes All Sky Survey (HIPASS) with
optical and near infrared datasets. We also show our preliminary results from
observations of a sample of 6 HI-deficient galaxies, which we identified in low
density environments.
