PHOENIX — Have the redear sunfish at Lake Havasu really gone quagga crazy?
Have these panfish that really can fill a pan, and are widely regarded as one of the better fish species to eat, found a surplus of invasive quagga mussels to munch?
A mystery remains: Redear sunfish at Havasu have been reaching world record sizes. But why, exactly?
Let’s dive into this piscatory puzzle.
Five years ago, “panfish” took on a new meaning.
We’re at the time of year when Lake Havasu tacked its world-record pin on the fishing map. On Feb. 16, 2014, Hector Brito caught a 17-inch, 5.78-pound world-record redear sunfish on a dropshot-rigged nightcrawler.
“I didn’t expect the record to last this long,” Brito said. “It’s amazing.”
This 45-mile fishing wonderland created by the Colorado River on the western-most strip of Arizona, adorned like a leather belt by the regal London Bridge, allows an angler to fish from the beach on the Arizona side and see the California mountains on the other. Some of those anglers said they witnessed a dramatic increase in the sizes of redear sunfish from 2009-2014 that — coincidence or not — occurred after invasive quagga mussels were first discovered in 2007 at Havasu.
In 2014, the U.S. Bureau of Reclamation (BOR) did a study about the effects of redear and bluegill on quagga populations and found these sunfish do consume quaggas. Even more, the redear reduced quagga numbers by as much as 25 percent. The experiments of the study were conducted in field enclosures of Lake Havasu, as well as in the BOR’s Boulder City, Nev. Fish Lab.
The Arizona Game and Fish Department can’t verify that redear sunfish, also known as “shellcrackers” because of their pharyngeal teeth (throat teeth) that allow them to crush crustaceans such as snails, are reaching unprecedented sizes due solely to quaggas as an additional food source. Other biological factors include Havasu’s food base of grass shrimp and redswamp crawdads.
Regardless, Havasu is home to some of the biggest shellcrackers on the globe.
Doug Adams, a former Lake Havasu City-based fisheries biologist for the Bureau of Land Management, said he also knows that redear sunfish eat quagga mussels. At the same time, he said that in 2005 — 2 years before quagga mussels were discovered in Lake Havasu – an electroshocking of 75 sites produced redear sunfish that averaged more than 2 pounds.
“From one standpoint, there wasn’t much fishing pressure until they started catching these bigger (redear),” Adams said. “Quagga could be a good contributor to their sizes. So it’s kind of a mystery.”
A mystery it might remain.
Still, some Arizona anglers have etched their conclusion: The increasingly larger sizes of redear is a quagga-based phenomenon.
For angler Mike Taylor of Phoenix, it’s simple:
“They don’t call them ‘shellcracker’ for nothing,” he said. “No quagga, then lots of quagga. Regular redears, then big redears after quagga show up … coincidence? Maybe, but I’d say increased food source equals bigger fish.”
In an email to the Arizona Game and Fish Department, an anonymous angler said he has been fishing extensively for sunfish in Lake Pleasant and the Colorado River. He wrote:
“And I have observed that not only do redears feed on quagga mussels, but bluegill and green sunfish do as well. After holding them in a live well for a short period of time, they will regurgitate bits of broken quagga shells until there is a layer approximately a quarter-inch thick in the bottom of the live well.”
And finally, some thoughts from Brito, the record holder:
“They eat a lot of quagga mussels. Everytime I fish for them, I search their stomachs and always find shells of quagga mussels.”
A new world record remains possible.
“I’m sure there’s a 7-pounder out there somewhere,” said John Galbraith, owner of Bass Tackle Master in Lake Havasu.