Watch: Whale Thrashes As It Tries to Escape Shark Net Off Australian Coast

A humpback whale was spotted thrashing in the water after getting caught in a shark net off Australia's Gold Coast early Monday morning.

A team of marine rescuers from the Queensland Boating and Fisheries Department approached the whale in a small rubber boat to cut away the net. After more than an hour, the rescue workers were able to set the whale free from one of the dozens of shark nets placed off Australia's beaches. The nets are thrown off the shore to protect swimmers from shark attacks, but marine experts in the region warn that these traps may cause more harm than good to marine life in the region.

"These shark nets are indiscriminate killers. There's whales, dolphins, turtles, dugongs—a whole range of animals caught," Sea World Director of Marine Sciences Trevor Long told the Gold Coast Bulletin.

As the rescue workers arrived, the whale rolled in the water as it attempted to escape, further entrapping itself in the netting. Video footage published by Nine News shows the panicked moments before the whale was set free.

"What Queensland Boating and Fisheries did was a very good job, they attacked it, started at the head of the animal, worked their way back. We were fortunate just to be there at the end, just to pull the net off," said Long.

Surveillance cameras are placed at some beaches around Queensland to alert rescuers if a whale becomes trapped in the shark nets. So far, during this migration season, this is the fourth whale that has been caught, Queensland Boating and Fisheries Patrol Shark Control Program Manager Jeff Krause said in a statement.

While humpback whale populations are now increasing after a 1985 ban on commercial whaling, these animals now face the threat of entanglement in nets and other fishing gear, according to the National Oceanic and Atmospheric Administration (NOAA).

Humpback whales travel great distances every year and have one of the longest migrations of any mammal on Earth. About 30,000 humpback whales make an annual 6,231-mile migratory journey between Antarctica and Queensland each year.

More humpback whales are expected to travel along the Australian coast, Long said, and the shark nets will become more of an issue since humpback whales regularly launch themselves out of the water and dive back in, making it easy for them to be caught.

Some whales that are trapped are never accounted for because they free themselves. Others might die fighting to escape, said Long.

"Not only is it a painful death, but it's long and slow. So these situations are very critical," he said.