Mike McFeely: Bigmouth Buffalo Centenarians

Duluth News Tribune:

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Don’t call the bigmouth buffalo a “rough fish,” a common and derisive moniker slapped on species viewed as less desirable than the sainted walleye and other hotly pursued fish. “They are amazing,” said Alec Lackmann, a North Dakota State University researcher in the Department of Biological Sciences. “They are one of the most exceptional freshwater fish species in the world.”

Lackmann would know. He led an NDSU team that unearthed this amazing fact: Bigmouth buffalo can live to be more than 100 years old, making them the oldest age-validated freshwater fish in the world. Lackmann’s study included one specimen that was 112 years old, and most of the fish he researched were more than 80 years old. The oldest fish came from lakes near Pelican Rapids, Minnesota...

According to NDSU, the bigmouth buffalo is now known as the longest-lived freshwater teleost (ray-finned fish) and the oldest age-validated freshwater fish in the world. “This is a paradigm shift in how we’re looking at these fish and should open a discussion about their real value,” Lackmann said. “They should not be called ‘rough fish,’ which carries a negative connotation. They should be viewed as an ecological asset.”

Kirsti Marohn: Surveying Fish in Streams for Water Health

MPR:

Chad Anderson and John Sandberg slosh through a muddy stream in hip waders, pausing occasionally to duck under overgrown branches or swat a mosquito.

Sandberg carries a long pole with a metal ring on the end. He moves it through the water, sending out an electrical current that temporarily stuns the fish. Anderson comes behind him with a net, scooping them up. “We want to capture every single species, every fish,” Anderson said. “The little species are sometimes just as important as the big ones...”

This slow and sometimes painstaking work is part of the MPCA’s effort to document and monitor all 80 of Minnesota’s major watersheds. The work has produced a wealth of data about the health of Minnesota’s rivers, lakes and streams.

Boom times for fish populations

NSF:

We’re all familiar with the idea of extreme events. Meteorologists keep us up to date on hurricanes, floods and high temperatures. Economists watch the stock market for signs of crashes or rallies. Researchers spend a lot of time trying to better predict these events, yet are often surprised by the outcomes. According to a new study in the journal Limnology & Oceanography Letters, when it comes to nature’s extremes, nothing seems to beat what happens underwater.

Scientists at the National Science Foundation (NSF) North Temperate Lakes Long-Term Ecological Research (LTER) site — one of 28 NSF LTER sites — are routinely measuring everything from water temperature to nutrient concentrations to fish populations in Wisconsin lakes.

Taking advantage of several decades’ worth of data, Ryan Batt, the paper’s lead author, and a team of researchers compared data on various physical, chemical and biological variables — 595 variables in total. They found that as the lakes’ temperatures rose and their nutrient concentrations increased, so did the number of organisms living there.

Solomon David: Bowfin, North America’s Underdog Fish

Cool Green Science:

Mudfish, dogfish, grinnel, swamp-muskie: the names alone suggest why bowfin (Amia calva) are generally not the most highly-revered among fishes.

With their prehistoric appearance and tenacious attitude, one may say they deserve their poor reputation. But the bowfin is in reality a fascinating, resilient, and even beneficial species.

What we see today in the backwaters and wetlands of eastern North America is a modern representative of a very ancient line of “primitive” fishes or “living fossils,” organisms that appear to have changed little over time. The sole remainder of a once diverse group; bowfins (order Amiiformes), have been around for over 150 million years.

One of my favorite fish to observe!

Krishnadev Calamur: A Fish With Cancer Raises Questions

NPR

Late last year, an angler caught a smallmouth bass in the Susquehanna River near Duncannon, Pa. That fish, officials from the Pennsylvania Fish & Boat Commission said this week, had a malignant tumor. It’s the first time this type of tumor has been found on a smallmouth bass in the river, the agency says.

Cancerous growths and tumors on fish are “very, very infrequent,” John Arway, the agency’s executive director, said in an interview.

”These cancers can be initiated by contaminants,” he said.

In addition to this story, more Information on the fish populations in the Susquehanna River is available here.

Forests are Good for Fish

Jason G. Goldman, writing for Conservation:

Fish rely on forests for their very survival. That’s because, in a way, they eat them. Debris from forests finds their way into rivers, lakes, and streams. The bacteria in the water break down the leaves and bits of tree bark and dead animals. Then the zooplankton eat those bacteria, and the fish eat the zooplankton.
Matt Tillett

Matt Tillett

One can eat only what is brought in.

Fish forced into the ‘foraging arena’ when lakes lose their trees

Adam Hinterthuer, writing for University of Wisconsin-Madison:

As water levels drop and submerged trees rise above the waterline, some fish are forced into the "foraging arena" to face predators

As water levels drop and submerged trees rise above the waterline, some fish are forced into the "foraging arena" to face predators

In attempts to predict what climate change will mean for life in lakes, scientists have mainly focused on two things: the temperature of the water and the amount of oxygen dissolved in it.

But a new study from University of Wisconsin-Madison researchers is speaking for the trees — specifically, the dead ones that have toppled into a lake’s near shore waters.

For fish in northern Wisconsin lakes, at least, these trees can be the difference between pastures of plenty and the Hunger Games.

Interesting study from the Center of Limnology.