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|SF; ChuckE on NCKA is the man to ask.
|Sharks, skates, rays, AND STURGEON male fish all have claspers.
i.e. EXTERNAL MALE REPRODUCTIVE ORGANS".....Covered more than a few times on the old board and with diagrams if I remember properly..
With proper education it is impossible to get a male sturgeon mixed up with a female, and in my experience, a slot female is gravid.............never have seen one that wasn't.
Unfortunately, this is untrue. Sturgeon do not have claspers and it is not possible to accurately determine the sex of adult sturgeon.
A new method, based upon examination of the urogenital opening, was published in 2003. Whilst it seems reasonably accurate, the photographs contained within demonstrate that the actual examination would be very tricky on a live, legal-sized sturgeon and would almost certainly break DFG rules. Here are some exceprts from that paper followed by a link to the original.
Vecsei et al. "A noninvasive technique for determining sex of live adult North American
Environmental Biology of Fishes 68: 333–338, 2003.
"......researchers have concluded that there is no external sexual dimorphism in sturgeon morphology
(Berg 1962, Scott & Crossman 1973, Doroshov et al. 1983)........... Thus most authorities have concluded that there is no reliable method for determining the sex of adult sturgeons from external morphology."
"We have developed a noninvasive technique to determine the sex of adult North American sturgeon by examination of the external morphology of live individuals.We analyzed four sturgeon species taken by commercial and scientific harvest: white Acipenser transmontanus, green A. medirostris, Atlantic A. oxyrinchus and shortnose A. brevirostrum. Males have a urogenital opening in the shape of a letter "Y", while the opening of females is in the shape of the letter "O". We accurately sexed 26 of 36 sturgeon using this criterion. Accuracy was highest in live fish (82%), and significantly lower in dead fish (29%). Dead sturgeon usually have the rectum prolapsed so that the urogenital opening is protruded, and thus making the sexes indistinguishable."
Link to the original: http://www.springerlink.com/content/r1753l46m5w47016/fulltext.pdf (You may not be able to access this without subscription. If anyone is interested I will send them a copy but posting the contents on here will almost certainly amount to a copyright infringment).