The Neal Smith National Wildlife Refuge, located in Iowa, is home to a conservation herd of 70-90 bison. But perhaps the most famous of the herd is Sparky, the bison that was struck by lightning in 2013 and, three years later, is doing surprisingly well.

"Sparky's wound is healing slowly and it may never heal completely," said Karen VisteSparkman, wildlife biologist at Neal Smith National Wildlife Refuge, who photographed Sparky last week."His limp seems to come and go and at last check he was walking well."

Sparky joined the herd at Neal Smith in 2006 after being transferred from the National Bison Range in Montana, according to the U.S. Fish and Wildlife Service (UFWS). Sparky earned his name after the lightning strike and is the only bison that has been struck at the refuge although it does occasionally happen across the country.

Sparky's condition was discovered during a survey in late July 2013, when VisteSparkman noticed a bull standing by himself.

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According to the UFWS "when [VisteSparkman] took a closer look through her binoculars, she noticed that Sparky looked bloody. This wasn't entirely surprising because bison bulls will often fight during the mating season and July tends to be a prime time for injuries. Upon closer inspection, it was clear that Sparky had been burned over a large area. His hump was missing hair and there was a large lump on his hind leg, which must have been the exit wound, meaning Sparky was lying down at the time of the strike."

Sparky wasn't expected to live long, but the fact that he kept walking was a good sign. Three years later, he is showing signs of relatively good health.

"He lost weight over the winter, like most of the bison, but is expected to gain weight now that things have greened up and there is more nutritious food available," said VisteSparkman.

The wildlife biologists at Neal Smith are still waiting on results from the DNA tests taken last fall from last year's calves to determine if Sparky father any calves after the lightning strike. He fathered three calves before the strike.

"Like most of the bulls, he hangs out by himself or with a small group of bulls most of the time, but is occasionally found with the family group," said VisteSparkman.

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