Environmental interpretation provides visitors with positive experiences in nature while managing their impacts. Existing research has concentrated on the influence of interpretive programs on visitor knowledge, attitudes, and behaviours. Little empirical research exists on how visitors perceive their environment. In this research we examine the effect of environmental interpretation on visitors' perceptions of the environment. The study took place in the Niagara Glen Nature Reserve, Canada. A survey is administered to visitors on self-guided experiences and visitors receiving two different interpretive programs. Perceptions are compared to ecological data. Visitors rated conditions higher than ecological data, regardless of participation in an interpretive program. There was no significant influence of an interpretive program on perceptions. Findings from this pilot study highlight the need for interpretive programs to examine their effectiveness of achieving its outcomes as well as the benefits of using a reference such as ecological data.