There’s a ton of information out there about the Baltic Sturgeon, one of the great success stories in this era of the sixth mass extinction event – here are a few historical places to start.
https://www.naturalsciences.be/en/news/item/6233
http://www.iucnredlist.org/details/230/0
https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1439-0426.1999.tb00221.x
Has some details on first eating of sturgeon/caviar
http://www.fao.org/docrep/006/Y5261E/y5261e06.htm
Article on leaping behaviour
https://www.nytimes.com/2001/10/21/sports/outdoors-the-lofty-mystery-of-why-sturgeon-leap.html
Sturgeon for tomorrow (fishermen + conservationsist)
https://www.sturgeonfortomorrow.org/resources-for-educators.php
Wiki in lithuanian
https://lt.wikipedia.org/wiki/Baltijos_a%C5%A1tria%C5%A1nipis_er%C5%A1ketas