The mangaka of Shinryaku! Ika Musume, Masahiro Anbe, announced in the 21st volume, as well as in Shounen Champion magazine, that the series will end in the following volume after being serialized in the magazine since 2007.

The manga series received a TV anime adaptation in Fall 2010 and a sequel in 2011, both produced by Diomedea among other studios. In addition to the TV series, it received three OVAs between 2012 and 2014. The series won the bronze prize in the Internet Vogue Word Award 2010 for Ika Musume's desinences "~ika" and "~geso."

Both seasons were licensed for North American release by Media Blasters in 2011 and 2012, respectively, which included dubbed versions in addition to the English subtitles. Both seasons were also simulcast on Crunchyroll.

Source: Otakomu