When you read stories about beached whales, like the one that died on a Queens beach last week, you may ask yourself: why doesn't anyone just put the whale back in the water?

Unfortunately, the solution isn't always so simple. By the time a beached whale is found, its organs and muscles are being crushed by its own weight. And many whales that beach themselves are already seriously sick, injured, or malnourished – so putting them back in the water won't do them much good.

“In cases where a stranded whale is found to be unfit to return to the sea, the most humane course of action is to minimize its pain and suffering wherever possible through euthanasia,” the Royal Society for the Protection of Animals says.

If a mother whale is stranded and cannot be returned to the sea, the most humane course may be to euthanize any of her calves are stranded nearby or swimming in the shallows.

“Sending a [dependent] whale calf back to the sea without the protection of its mother means that the calf is left to starve and is susceptible to attack by sharks,” the RSPCA says.

However, if someone does stumble across a beached whale, they can still take steps to try and keep it alive, like spraying it with water, until officials arrive at the scene. Some smaller cetaceans, like dolphins, may survive stranding. But the ultimate decision to euthanize a whale or dolphin should be made by veterinarians and marine mammal experts.

“Each case will be assessed as an individual one, but the presumption will probably be that the animal is euthanized unless we have a very good reason not to.” an RSPCA spokesman told the Daily Mail in 2009.

Whales and dolphins beach themselves for many reasons. Older or sick whales may not have the strength to keep up with their pod or resist currents that draw them ashore. Whales may also be injured through encounters with nets or boats, or starving.

Some whales may beach themselves because they got lost. This can happen in many ways – a whale could be chasing prey and caught by a wave or stranded by the high tide. A whale could be chased by a predator into the shallows. Beaches with sandy and gentle slopes may not resonate with the whale's sonar, leading it to believe its in deeper water than it actually is, according to New Zealand-based whale rescue group Project Jonah.

Another possible threat to whales is underwater sonar. Environmental groups have called for the U.S. Navy to reduce underwater sonar tests, especially during times of the year when whales are feeding or calving. In January, a coalition of conservation groups and American Indians filed a federal suit against the National Marine Fisheries Service in California, challenging its approval of Navy sonar use along the West Coast.

Meanwhile, scientists are still examining the whale that washed up and died at Breezy Point in Queens. The 60-foot-long finback should have weighed about 60 tons, but was clearly emaciated when it washed up, the spine visible beneath the skin. The cause of the whale's death was still up in the air, but it's possible that the whale was simply elderly – finbacks can live for as long as 90 years, according to the New York Times.

Eventually, the finback will be buried underneath the beach where it stranded itself after biologists perform a necropsy, according to officials.