Management of a popular game fish, the smallmouth bass

Date:
October 19, 2020
Source:
University of Missouri-Columbia
Summary:
For recreational fishing enthusiasts, the thrill of snagging their
next catch comes with discovering what's hooked on the end of the
line. In many freshwater streams and rivers -- across the central
and eastern parts of the U.S. -- anglers are often catching a
popular freshwater game fish: the smallmouth bass. Now, scientists
have discovered a new level of biodiversity within that species.



FULL STORY ==========================================================================
For recreational fishing enthusiasts, the thrill of snagging their next
catch comes with discovering what's hooked on the end of the line. In
many freshwater streams and rivers -- across the central and eastern
parts of the U.S. - - anglers are often catching a popular freshwater
game fish: the smallmouth bass. Now, scientists have discovered a new
level of biodiversity within that species.


========================================================================== Previously, scientists identified two subspecies of smallmouth bass: the widespread Northern smallmouth bass and a much smaller subgroup called
the Neosho smallmouth bass. The Neosho are native to an ecologically
isolated region of the lower Midwest known as the Central Interior
Highlands, which weave through southwestern Missouri, northern Arkansas
and northeastern Oklahoma.

To help the conservation departments manage the present diversity of
this smaller subspecies of smallmouth bass, two University of Missouri researchers - - Joe Gunn and Lori Eggert -- worked with the Missouri
Department of Conservation, Oklahoma State University's Department of
Natural Resource Ecology and Management and the Oklahoma Cooperative
Fish and Wildlife Resource Unit of the U.S. Geological Survey at Oklahoma
State University to collect over 800 fin samples from smallmouth bass at
43 different sites in the Central Interior Highlands. The MU researchers
helped analyze the samples for genetic diversity.

"Management is necessary because this is a gamefish," said Eggert,
a conservation biologist and professor emeritus in the Division of
Biological Sciences in MU's College of Arts and Science. "Human actions
have already strongly affected the species and will continue to do
so. This management generally takes the form of 'stocking' to enhance opportunities for recreational anglers. If the source and subspecies
of fish used in stocking particular streams is not considered, stocking
events could lead to 'genetic swamping' of the local fish. In some cases,
this could lead to one subspecies dominating the other in streams outside
its native range. Letting 'nature take its course' is not an option." For years, Eggert has studied the ecology and evolution of animal populations, including most notably African forest elephants. She originally wanted
to become a veterinarian, but her passion for conservation biology
developed while in college and grew as she served as an intern in the
genetics program at the Zoological Society of San Diego. There, she was
able to learn about conservation efforts on behalf of species such as
the Przewalski's horse of Mongolia and the giant panda in China.

Eggert knows a proper understanding of the genetic diversity of animal populations is important when managing these populations.

"With the Neosho being a native fish to the Central Interior Highlands,
this study highlights the importance of thinking about management
actions when moving fish between streams," Eggert said. "In the past,
it's just been 'a fish is a fish,' and hatcheries were providing fish
without anyone first considering where these fish are originally coming
from. It's not just 'a fish is a fish.' A fish being added to a Neosho
stream should really come from a Neosho stream.

We also need to look at which Neosho stream is involved, because each may
be home to a genetically different population, and we don't quite know
yet how important the mixing of these different genetic populations is
to their overall health within an ecosystem." Gunn, a graduate student
in MU's College of Arts and Science, is currently working toward a
doctorate in the Division of Biological Sciences, with an emphasis in conservation biology. Since he was little, he's always loved nature,
and enjoys thinking about complex concepts in ecology and evolution. He
wants to use his knowledge and understanding of animal species to make a positive impact on the management and preservation of threatened species
and their environments.

Gunn said this study shows there is considerable diversity within the smallmouth bass family.

"Our methods have been used before to identify previously unknown lineages
of animal populations," Gunn said. "This can be applied to species within
any group, whether it's mammals, fish, reptiles or birds. There are
also very interesting dynamics between different groups, and these same
methods can also be used to identify genetic structures and morphological differentiation within a specific species. Here, we've found considerable diversity between the two known subspecies of smallmouth bass, the Neosho
and the Northern smallmouth bass, the latter of which can be found in
a larger area of the U.S."

========================================================================== Story Source: Materials provided by University_of_Missouri-Columbia. Note: Content may be edited for style and length.


========================================================================== Journal Reference:
1. Joe C. Gunn, Leah K. Berkman, Jeff Koppelman, Andrew T. Taylor,
Shannon
Brewer, James M. Long, Lori S. Eggert. Complex patterns of genetic
and morphological differentiation in the Smallmouth Bass subspecies
(Micropterus dolomieu dolomieu and M. d. velox) of the Central
Interior Highlands. Conservation Genetics, 2020; 21 (5): 891 DOI:
10.1007/s10592- 020-01295-1 ==========================================================================

Link to news story: https://www.sciencedaily.com/releases/2020/10/201019155920.htm

--- up 8 weeks, 6 hours, 50 minutes
* Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1337:3/111)