are these two sturgeon different?

[yohan]

first 3 is my sturgeon which i believe is a sterlet and the last 2 is one that i got from here http://www.monsterfishkeepers.com/forums/showthread.php?t=167382&page=3 they call it white sturgeon. can someone explain it to me. i always saw these kind of sturgeon in LFS and thought it was the same as mine only with more spiky scoutes. are they different species? i am aware that white sturgeon can grow up to 14' as said in wiki

 

[andyjs]

Yep, first 3 are a Sterlet (sometimes called Little White) and last two are a white. The Sterlet (Acipenser ruthenus) is a European species that maxes out around 4' (or less in captivity). White sturgeon (A. transmontanus) are a North American species from the Pacific coast area. They do indeed get 14' and sometimes larger in the wild. They are slow growers though. The fish hatchery I worked at has had 10 of them for about 16 years and the largest is right about 4'. The easiest way to tell the difference in those pictures is the head shape. Notice how the sterlet's nose tapers to a point and curves upward while the white's isn't as pointed and does not turn up.

 

[snakeheader]

sterlet and whites

 

[kydsexy]

hope you're getting that backyard pond ready! yeah for white sturgeon, my friend works at a hatchery in iowa or idaho...one of them