East Caribbean States color varieties reported

A puzzling array of East Caribbean States color varieties has been reported. The backs of the notes are identical, but as you can see by examining the scans below—all provided by a single source and scanned using the same equipment and settings— the fish in the lower left corner on the front is printed in different colors on different notes. The standard color of brown/green switches to red, reddish brown, and green on these notes. Normally I might attribute this to ink variation over time, but the two rightmost notes are consecutive serial numbers and the fish color changes dramatically. All of these scans are of undated (2003) ECS $5 notes with the St. Vincent suffix V. If anyone can explain what’s going on here, or if there are similar color varieties in other denominations, please share that information.