Those heading to South Padre Island may encounter tar balls that are washing up along the shore.

“It's part of nature, and it's also mixing with the sargassum now,” Cameron County Marine Extension Agent Tony Reisinger said.

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The tar balls are caused by 17,000 tons of oil separating from the bottom of the ocean every year. The oil hardens underwater and the current moves it to shore.

“During the hot summertime, it melts a little bit and if you step on it, it sticks to your skin, so you need to be able to clean it off too afterward,” Reisinger said.

Dish soap can be used to remove the oil on your skin.