Jun Matsui has had a lifelong passion for wildlife, which led him to begin bird guiding in 1993 while working as a volunteer ranger at Hikarigaoka Nature Park in Tokyo, Japan. He went on to work for the Japanese Environment Agency, where he managed wildlife data, contributed to environmental education initiatives, and guided at several nature reserves across the country.

In 1999, Jun moved to Australia, spending a year travelling and volunteering at key birding locations, including the Broome Bird Observatory. He later became a specialist bird tour guide for inbound Japanese groups, based in the tropical birding hub of Cairns, Far North Queensland.

Jun is a respected wildlife photographer and author. He wrote a popular Japanese-language field guide to the birds and wildlife of the Cairns–Atherton Tablelands region. He also co-authored A Field Guide to the Birds of Far North Queensland (New Holland, 2019) with Phil Gregory, contributing the majority of the photographs.

Since joining Sicklebill Safaris in 2007, Jun has led birding and wildlife tours across Australia, Papua New Guinea, the Pacific, and Asia — including multiple tours to his native Japan each year.