People who regularly exercise along White Rock Lake say they've learned to pick up the pace because of a sickening smell along one stretch of trail.
Stretching 9.3 miles around, lake enthusiasts often take their time soaking in the scenery -- but not while on the curve along West Lawther.
"It's about at the end of my run, so I typically breathe through my mouth, and it's kind of a momentum to get over to the finishing spot," runner Adrienne Lichliter said.
While runners hold their breath, a flock of double-crested cormorants sits high above the northwest trail in the comfort of the treetops.
Runners say the birds have a putrid odor.
"It's kind of a mix of bird waste and digested fish, I guess," runner Eric Lindberg said. "I think it's impossible to get used to that smell."
People who often go to the lake said the smell tends to get worse in the winter.
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Lake goers said they have just learned to deal with it in one way or another.
"I heard they were endangered in some way shape or form or protected, so you can't chase them out of here," Lindberg said.
Many lake visitors said they are resigned to the fact that, at the end of the day, White Rock Lake is the birds' home.
"We're kind of like their guests," bicyclist Michael Bent said.
The birds are one of 800 species protected under the Migratory Bird Treaty Act.