A toxic red tide continues to bloom and expand in the waters of the Gulf of Mexico as it nears the coast of South Florida. Officials say the maroon-tinged algae bloom is one of the largest Florida's waters have seen in a decade.

Researchers with the Florida Wildlife and Conservation Commission, the University of South Florida and Mote Marine recently returned from a three-day research cruise, during which they deployed a remote control underwater robot to collect data needed to create a 3-D image of the bloom.

Researchers say the red tide is some 80 miles long and 50 miles wide, and is only 30 miles from the coast in some places. It stretches as deep as 130 feet.

"It may come inshore, and when it does, you may see some effects at your local beach, such as you may get a little dry cough, get the watery irritated eyes kind of thing from the toxins," Mote researcher Haley Rutger told local NBC affiliate WFLA.

But while a red tide is mostly just a nuisance for beach-goers, it can be deadly for local marine life. Dead fish, sea turtles and even manatees can be found washed ashore as the algae encroaches upon the shallows.

Rutger says researchers in Florida hope their ocean observations can help better predict when red tides will occur, how big they'll grow and where they'll move to -- like weather forecasting. He and his colleagues also want to better understand how the toxins affect the ocean ecosystem.

"How long the animals keep the toxins in their systems and that kind of thing, it's just important to understand the effect on animals as it is to understand the effects on humans," Rutger added.