December 2024 - 44

manager, said the lab tests about 800 samples per
year for BKD, which equates to about 4,000 fish.
Smith added the number of fish tested for BKD
has increased since 2020 because of Wyoming's
participation in the Colorado River Fish and Wildlife
Council, which is a partnership among state
agencies within the Colorado River Basin. Another
reason for more BKD tests is the increase of testing
of wild fish populations.
" Fish managers are interested in moving and/
or transplanting various fish species throughout
Wyoming. These wild populations undergo the
same rigorous testing regime as our hatcheries
and rearing stations do, including BKD testing, "
Smith said.
WHAT'S NEXT?
Megan Smith, laboratory scientist with the Wyoming Game and Fish Department's Fish Health Laboratory, examines a
slide for possible fish pathogens. (Carl Smith, WGFD)
Scan the QR code to learn
more about the Wyoming
Game and Fish Department's
10 fish hatcheries and rearing
stations.
the actual disease where there's been any or significant
fish die-offs, but at some very low level the
causative agent is there.
" We've historically used these wild populations
to infuse the genetics of the fish we raise, and now
it's becoming a lot more difficult as we need to be
aware of any potential risk, " Campbell said.
Fish must be tested in order to determine the
severity of BKD prevalence. However, the most
accurate testing requires fish to be lethally sampled.
In many cases, the number of fish required to get
an accurate count of those infected could severely
reduce the population in that particular water.
Fortunately, the grayling in Meadow Lake have a
strong enough population to sustain proper testing.
" Grayling in Meadow Lake did test positive
for Renibacterium salmoninarum a couple of years
ago. However, the fish tested last year came up
negative - telling us the actual prevalence is at
an extremely low level, " said Kris Holmes, Game
and Fish spawning coordinator. " We are going to
test fish again this year at a higher prevalence. "
Carl Smith, Game and Fish fish health program
44 | December 2024
Continued monitoring of water quality and
systems at all of Wyoming's hatcheries, along with
monitoring for pathogens in hatcheries in the wild.
This isn't new work, just continued efforts by Game
and Fish. The same can be said for ways to cover
open-water areas at hatcheries.
There's also a lot of work that's been happening
for quite a while that will continue. Holmes
said, for instance, that when crews go out to do a
spawning operation, they arrive with clean water.
In other words, they transport water from a clean,
pathogen-free source. Eggs are spawned, rinsed,
treated with iodine and shipped in clean water.
Protocols are in place to properly clean equipment,
ranging from trucks and nets, and even boots
and clothing from spawning personnel when going
to and from a spawning operation. Disinfection
stations are located throughout all of Wyoming's
hatcheries to prevent the spread of pathogens and
diseases. This is for Game and Fish personnel and
visitors.
" Over the last few years, we've continued to
strengthen our biosecurity protocols, and we will
continue to do that, " Campbell said.
Campbell added if Game and Fish knew nearly
a century ago what it knows now about fish pathogens/diseases
and aquatic invasive species, many
of the state's hatcheries and rearing stations would
have been built differently - ranging from site
locations, protecting water supplies, covering tanks/
raceways and water sources.
" Now, however, it's about how we retrofit our
facilities to meet these same goals, " he said.
- Robert Gagliardi is the associate editor of Wyoming
Wildlife magazine.

https://wgfd.wyo.gov/fishing-boating/fish-hatcheries

December 2024

Table of Contents for the Digital Edition of December 2024