Investigators returned to the Whiskey Bay Bridge where Shunick's bicycle was located on Wednesday to re-examine the area with sonar.
Images recorded on the sonar equipment were reviewed and sparked the operator's interest.
Divers from the East Baton Rouge Parish Sheriff's Office were called in to conduct the search beneath the water, but nothing of evidence value was located.
22-year-old Mickey Shunick went missing after leaving a friends residence on her bicycle in Lafayette around 2:00 a.m. Saturday, May 19.
The investigation remains ongoing.