Virginia fisherman Jacob Moore hooked an unusual bass on the James River recently: A golden largemouth that’s such a rarity even a dedicated tournament angler like himself had no idea they existed. “When I hooked into that one, I thought I had a saltwater fish on at first, but lo and behold, it was a largemouth,” Moore told the Virginia Department of Wildlife Resources (VDWR). “[It was] a very different [kind of] largemouth, though. I haven’t seen anything like that before.”

The fish’s unusual coloration wasn’t caused by albinism, which is characterized by little or no melanin production, but by another genetic variation in pigmentation called xanthism. “Golden largemouth bass are extremely rare and most anglers have never seen them, let alone heard of them before,” said Alex McCrickard, Virginia Department of Wildlife Resources Aquatic Education Coordinator, in a VDWR press release. “The fish is a product of a genetic mutation that alters the skin pigments called xanthism. Yellow pigmentation dominates in xanthism, as you can see in Moore’s golden largemouth.”

Moore, an arborist who regularly competes in local bass tournaments, was practice-fishing the lower James River near Chippokes State Park in preparation for an upcoming tournament when he caught the distinctive golden-hued fish. He measured its length at 16 ½ inches, snapped a few photographs, and released it back into the James River.

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Just how long are the odds of catching a golden bass? When Arkansas angler Josh Rogers boated one at Beaver Lake in May 2021, Arkansas Game and Fish Commission biologist Jon Stein said, “Josh needs to buy a lottery ticket, because he caught one fish in a million.” In that case, Stein also attributed the golden coloring—which stumped both Rogers and his fishing partner—to xanthism, noting “this is very rare and does occur naturally.”