Despite the ease of accessing information in the digital age, environmental science students need information literacy (IL) to competently tackle complex problems and sustainability challenges. Students' experiences and teachers' perceptions of student IL skills in an environmental science program were investigated through student questionnaires and teacher interviews to identify students IL competence and eventual learning gaps in the program. Students expressed confidence in IL, more strongly in basic skills such as information search and source criticism than advanced skills; critical thinking and analysing, interpreting, and creating information. They found formulating problems and locating and assessing information to be challenging, despite repeated training in tutorial groups. Teachers similarly perceived students to be most competent in accessing relevant information while using information is more challenging. This could be linked to the complexity and interdisciplinarity environmental science. Findings suggest that IL learning gaps could be bridged by greater focus on systematic IL training, intentional training on advanced skills, and iterative training of both basic and advanced skills by strengthening faculty and librarians collaborative teaching.