Those who live near the ocean on the West Coast are reporting many jellyfish-like creatures washing up on local beaches. These animals, called velella velella, could be victims of changing wind currents and ocean temperatures.

Velella velella are "by-the-wind sailors" because they are highly affected by the wind. They are mostly blue, with a clear fin sticking up from their body, which is smaller than the palm of a hand.

"Every now and then, the currents and the winds will change and these guys will, instead of being pushed out to sea, they actually wind up on the beach," says David Bader, director of education at the Aquarium of the Pacific in Long Beach, Ca.

Like their cousins, the jellyfish, velella velella do sting, but not enough to break through skin. They feed on fish eggs and plankton and spend most of their lives like tiny sailboats. They set adrift on top of the ocean, the wind picking up their fins, which act like sails, and blow them where it will. Unfortunately, they sometimes end up on shore, where they die.

Velella velella aren't the only sea creatures washing up on beaches, though. On the East Coast, swarms of moon jellyfish and barrel jellyfish are often seen close to shore or on beaches.

This rise in numbers of gelatinous sea creatures could be the result of a great deal of plankton near the shores, which could be caused by agricultural runoff. Also, many of jellyfish's natural predators are wiped out due to overfishing.

Like velella velella, jellyfish are also affected by ocean currents and winds. Most jellyfish move independently, but when the winds blow a certain way, it can affect where they end up.

The Earth's temperature also affects jellyfish populations. In 2013-14, a warmer winter led to more barrel jellyfish. However, the previous year's colder winter led to less.

Regardless, when humans get a sneak peek at these mysterious creatures, we're reminded of just how much we don't yet know about many of the ocean's mysteries.

"A lot of people probably never knew an organism like this existed in the world," says Bader. "And you know the winds change, and all of a sudden they wash up on shore and we get to see what the ocean is really made of."

Marine biologists estimate more velella velella and jellyfish will end up on shores in the future. More humans now have access to the ocean, so we're more likely to see these creatures wash up on the beach.