After reading the Fish & Game explanation about the difference between a Green Sturgeon and a White Sturgeon on my report card, I've found it much too vague.
To start, when Fish and Game refers to the difference in the barblers (whiskers) placement. I have found the barblers placement can be too close to the same to be a reliable reference as shown in photo left (picture 1. is a Green Sturgeon picture 2. is a White Sturgeon). I also have found the length of the snout as shown on your report card to be misleading as well. While a White Sturgeon is consistent the Green Sturgeon can vary as seen in photos 1. & 3.
Some have long flat shouts as seen in photo 3. While others are short like a White Sturgeon, but pointed, compare photos
1. & 2. After consulting with a Fish & Game biologist it would seem the larger Green Sturgeon typically have a short snout like a white. While the smaller Green's typically look more as pictured on your report card. What's commonly referred to as shoulders, on some Green's are thick as also shown on your report card. Others may be more streamline like a White Sturgeon as seen by the Green Sturgeon pictured in photo 3. The fastest way I've found to spot a Green Sturgeon in the water, is by the green strip on the lower side of the body and a dark green or Black strip down the center of the belly as seen in pictures 1. & 3. On White Sturgeon there are no stripes. The dark color ends just below the midlateral plates. The is basically white on the lower sides and belly, Thus a White Sturgeon.
Next we have the midlateral line or plates. The Green Sturgeon has a ragged or erratic looking line, but one solid line. As seen right in photo 4. Not the neat and orderly diamonds you'll find on a White. Also on a White the diamonds may or may not be touching each other as shown below in photo 5.
The midlateral plates on a Green Sturgeon are noticeably taller, longer and curving back towards the tail, almost hook like. As seen in picture 6. lower right. The dorsal plates are very much like the midlateral plats of a Green Sturgeon and taller than you'll find on a White Sturgeon.
To sum it up, a Green Sturgeon is green. The first one I caught looked to me like a White Sturgeon that must have been in some green scummy water. It had a look to it as if it was covered in a green translucent moss. The same moss you've seen growing in waters most everywhere.
So good luck my fellow Sturgeoneers. I hope this will help you to identify your Green Sturgeon. And not hear those dreaded words from a Fish & Game officer "sign here please, and press hard there's four copies"...
How to Identify Green Sturgeon
By Rob Reimers
Note; that removing green Sturgeon from the water was legal at the time this picture was taken.