These animal pictures are created using your ordinary biro or ballpoint pen. I started the series in 2005, and have recently done many more works as I have discovered coloured pens.
I also find this medium very convenient as it isn't messy, and biros are easy to carry or find lying around while I have moved from place to place. I prefer it to pencil as it produces a much more dramatic and crisp image. Even though there's no erasing mistakes, there are very few images that I have discarded.
I work from a photo, and build up from faint shading, continually darkening it, constantly adjusting for errors. This way the shapes gradually take form, and old errors are hidden by new shading as I darken the picture. They usually take me 2-4 hours to produce.