NEAR BROWNSVILLE – This year's dead zone has Rio Grande Valley shrimpers on high alert.

The dead zone is an area in the Gulf of Mexico with low oxygen levels and is known to kill marine life.

The National Oceanic and Atmospheric Administration said it's the third largest they have on record and is about the size of New Jersey.

According to NOAA, most the dead zone is located at the mouth of the Mississippi river, which leads into the Gulf of Mexico.

It’s formed primarily by human activities such as agriculture and wastewater as they wash out into the Gulf from rivers.

The agency said the excess nutrient from this stimulates an overgrowth of algae, which results in low oxygen levels in the water.

NOAA estimated this will slow shrimp growth, leading to fewer large shrimp as we head into the summer months.

CHANNEL 5 NEWS spoke with local shrimpers who said they are keeping their eye on it.

"It's not a huge area in comparison to the amount of space that we have to trawl. So, we simply avoid it. It hasn't really been an issue with our industry. Obviously, if it continues to grow then yes that's going to raise some red flags," Texas Shrimp Association executive director Andrea Hance said.

NOAA said this may impact shrimp prices depending how long it stays. They said some things which can disrupt a dead zone are tropical storms or hurricanes.