A 126-page document that contains or references most of what is known about the endangered pallid sturgeon in the Missouri and Mississippi rivers has been completed and released to the public.
The U.S. Fish and Wildlife Service’s Pallid Sturgeon Revised Recovery Plan also lays out specific tasks that could help restore the fish across its once 3,000-mile long habitat that stretched from the Missouri and Yellowstone rivers to the mouth of the Mississippi River.
“The recovery plan is sort of taking a step back and looking at the life history of the species and trying to understand” what challenges the fish faces and how to address those challenges to ensure that the fish is eventually delisted, said George Jordan, who leads the U.S. Fish and Wildlife Service’s pallid sturgeon recovery team from his Billings office. “There have been a substantial amount of changes to the Missouri and Mississippi rivers that have impacted the species.”
The pallid sturgeon is considered to be a relic of the dinosaur era. The fish’s fossil ancestors date back more than 70 million years. The draft revised plan summarizes and updates the available information on the species’ life history and needs, re-evaluates the threats to the species and identifies recovery efforts.
The pallid sturgeon was listed as an endangered species in 1990. For now, the fish are being artificially sustained through stocking. The ultimate goal is for pallid sturgeon to reproduce naturally in the wild. Although the fish are spawning, there’s no evidence that their larva are surviving after hatching. The recovery plan calculates that the species may not be fully recovered until 2047 at an estimated cost of $239 million — but that’s no deterrent.
“It’s our goal to conserve and protect this ‘living dinosaur’ from extinction for future generations of Americans,” said Noreen Walsh, USFWS Mountain-Prairie regional director in a press release.
In Montana, some of the tasks outlined to restore the species involve dams like Fort Peck, Tiber, Canyon Ferry, Tongue River and Yellowtail where altered flows at specific times of the year could provide better conditions for successful spawning of the bottom-feeding fish.
Data collected from tagged fish suggests that the fish respond to river flows and water temperatures. Last year, a tagged wild female pallid sturgeon migrated about 175 miles up the Missouri River to the Fort Peck Dam, then went up the Milk River before turning around and coming back to the Missouri. Unable to find the right conditions, the female swam back downstream and entered the Yellowstone River — about another 175-mile trip — where she spawned.
“Something wasn’t quite right for spawning to occur in the Missouri River,” wrote Tyler Haddix, a Fish Wildlife and Parks fisheries biologist, in the agency’s 2014 fishing newsletter. “The main difference (from successful pallid spawning in 2011) was flows released from Fort Peck Dam were not conducive to pallid spawning. This triggered the fish to look for better conditions. The data FWP has collected on these majestic fish continues to point to the need for altered flows from Fort Peck Dam, which is impeding adults to migrate up and spawn within the Missouri River.”
Modification of Intake Diversion Dam on the Yellowstone River north of Glendive to allow pallid sturgeon passage is another dam project that has the potential to help the fish. Right now the dam blocks upstream migration by pallid sturgeon. Modification of Intake is being designed by the U.S. Army Corps of Engineers whose staff is struggling with building a structure durable enough to withstand the Yellowstone River’s destructive ice flows while still meeting the slow flow speeds necessary for the fish to move upstream.
Dams aren’t the only things that have harmed the pallid sturgeon’s habitat and complicated the fish’s recovery. Other problems include human modification of river habitat, such as river channelization; degraded water quality and disease.
“Intake, just because of its sheer size and magnitude, people are drawn to it,” Jordan said. “But there’s a lot of research, monitoring, small and big habitat projects also going on.”