A large amount of dead fish were spotted washing up at Port Isabel and South Padre Island area.

Officials say the dead fish are a result of last week's cold weather.

The fish washed up near the lower Laguna Madre area just off the bay. Weslaco resident, Jesse Fonseca, spent the day out there fishing.

"This is my first day out after the freeze, and I was shocked," Fonseca said. 

The fish were identified as mullet fish. The Texas Parks & Wildlife Department said this is the result of the recent cold weather that sent temperatures plummeting.

"It generally drops the water temperature below their lethal limit," ecologist Willy Cupit said. "So they basically freeze to death." 

Culpit said he started getting reports about the dead fish a couple of days ago.

"They've been lying on the bottom pretty much all week and now that the water temperature is starting to warm up a little bit those fish are starting to decompose and are floating to the surface," Culpit added.

Though some people have shown concern, Port Isabel police say they are monitoring what's happening and are letting Mother Nature run its course.

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