[5] In Siberia from 1948 to 1952, Židonis worked as an assistant forest industry worker, locksmith, blacksmith, tractor operator, foreman, and mechanic, consequently missing six years of school.

[4] After the death of Stalin in 1953, mass deportations to Siberia began to gradually end, and in 1955 Židonis managed to get employed in the Tomsk Railway Institute.

Knowing that obtaining the academic aspirant degree would be hard due to his background of deportation, Židonis began participating in activities of a students' scientific society.

As a result, Židonis settled in Marijampolė (then called Kapsukas), and worked as a chief engineer of the factory's Special Construction Bureau.

He would defend his doctoral dissertation in 1962[8] and became a lecturer as well as docent at the Kaunas Polytechnic Institute, where he created a laboratory for his automated machines[2] which were highly appreciated by the then Minister of Chemical Industry, Leonid Kostandov.

[5] Under the leadership of Židonis, original and efficient automatic machines for packaging food and chemical products in film containers were created.

This is evidenced by a certificate signed by Jonas Šeškevičius, the then director of the Marijampolė food industry factory, which stated that only in fifteen years (from 1971 to 1986) the packaging machines created by Židonis yielded a 165 million ruble economic profit.

[2][7][9] Right after the January Events, Židonis was called by the third cabinet of the government led by Gediminas Vagnorius to work as the minister of natural resources from 1991 to 1992.

In 2009 Židonis also invented new combustion technology for the heating boiler, which made it possible to reduce the slagging of the burning straw pellets, making it more environmentally friendly.