Biologists found two plastic bags and a shredded balloon in the stomach of a female rough-toothed dolphin calf stranded Tuesday on Fort Myers Beach.

Though rescuers worked into the wee hours Wednesday, the emaciated dolphin was in such poor condition they decided to euthanized her, said Michelle Kerr of the Florida Fish and Wildlife Conservation Commission.

Under normal circumstances, so small and young a dolphin should still have been with her mother, but somehow, she wound up far from her deep-water home.

Previous coverage:Lost deep-water dolphin calf euthanized on Fort Myers Beach

Although the man-made things in her stomach are a “significant finding,” scientists haven’t yet established a final cause of her stranding and death.

“Marine mammals strand for a reason,” FWC officials wrote in a release. “Often the animals are sick or injured … There are many additional factors to consider, such as underlying illness, disease and maternal separation.”

The wildlife scientists send the samples collected from the necropsy for analysis.

"This finding highlights the need to reduce single-use plastic and to not release balloons into the environment,” the release said.

The dolphin's death underscores the importance of keeping plastic bags out of the water, said D.J. Thiele, a Fort Myers resident whose 13-year-old daughter, Ella is on a mission to get them banned.

“This is such a call to action,” he said, “pushing us harder to get our goal of banning plastic bags to become a reality.”

Over the past few weeks, the father/daughter team has built a website, made TV appearances and started a petition to convince others to join them.

More than 500 people have signed so far, and Ella, a seventh-grader at Cypress Lake Middle School in Fort Myers, has been meeting with politicians and business people, including Sanibel City Councilman Richard Johnson.

Johnson is one of the owners of Bailey's General Store, which no longer offers single-use plastic bags.

Fort Myers Beach and Sanibel have banned plastic straws, but the Thieles say there’s still much to be done.

“The topic is hot right now,” he said, “but with sealife washing up with plastic in their bellies, it's time to get serious.”

By the way — Here are five things to know about rough-toothed dolphins

How to help

If you find a stranded dolphin or other marine mammal, call FWC’s Wildlife Alert at 888-404-3922 so trained experts can respond. Officials urge people not to push animals back into the water as it can delay examination and treatment and often results in the animal re-stranding in worse condition.