This paper examines the impact of fish consumption advisories on recreational behavior and visitor welfare using large-scale mobility data from Michigan. By integrating cellphone-based location data with a discrete choice modeling framework, we estimate the causal effects of advisories on recreation site selection and quantify the associated welfare benefits of disclosing risks. Our findings show that advisories significantly deter recreational visits, with an average visitor willing to pay approximately $72 per visit to avoid sites under advisories. We also find that disclosure on advisories led to aggregated welfare benefits of $3.45 million annually, highlighting its broader recreational benefits.