Range: Oceans worldwide Habitat: Deep ocean Size: About 1 foot (30.5cm) long on average; Up to 5 feet (1.5m) long Diet: Planktonic organisms Threats: Sea stars Life span: Unknown; Estimated to 10,000 years

Transcript:

Today on Animal Fact Files we’re discussing glass sponges. There are more episodes to come, don’t forget to subscribe! This time we got TriggerPianist’s request right! Glass sponges are sea sponges, but they’re different from other sponges in how their bodies are built.

I may sound like a Captain Obvious here, but as the common name implies, glass sponges are made of silica, and they form rigid skeletons that can encourage the growth of deep water underwater communities much in the same way coral reefs do in shallow waters. Their bodies literally become the permanent homes for some deep sea dwelling animals, but we’ll touch on that in just a bit!

On average, glass sponges are found between 650 and 3,200 feet (200-1000m) below the ocean’s surface, though they have been found in even deeper waters. Their difficult to reach environments have made study of them difficult, but some glass sponge colonies are found in places where they can be observed by SCUBA divers.

Like other sea sponges, glass sponges are filter feeders, but they have the unique ability to conduct electrical currents even though they don’t have nerves. When a glass sponge is touched, such as by a large cloud of sand kicked up by a passing animal, it is able to respond to the touch of the sand by “turning-off” the water filtering in that part of its body to help ensure its pores don't become clogged with sand - a nifty trick for an animal that doesn’t have fingers to pick out particles and can’t move from its location.

Glass sponge reproduction is not well understood, however, it seems that eggs are developed and fertilized within the animal and larvae are then released into the water column where they will quickly settle to the ocean floor, meaning they don’t take much time to spread out from their parents. Seems like a risky move if you ask me.

Supposedly these sponges can live 10,000 years or more - don’t get me wrong, I love my parents, but I’m not sure I could enjoy spending 10,000 sitting next to them permanently settled on the bottom of the ocean. Of course, I’m not a glass sponge. This quick settling in larvae may be in part why glass sponges form aggregations so close together. Glass sponges may grow two or more inches (5cm) per year, and reach sizes of around five feet (1.5m), though closer to one foot (30.5cm) is more common. They tend to grow upwards, but a larger specimen can be as wide as it is tall. They form bowl-like or branching structures, and their bodies can become homes for other sea creatures.

While glass sponges have to fear sea stars who may find their seemingly inedible crunch an enjoyable experience, glass sponges are generally protected from predation. Brittle stars and crustaceans, such as crabs and shrimp may move in and utilize the protection provided by the body of a glass sponge. There’s even one shrimp-like creature that makes its way into the body of a glass sponge along with its mate and together they grow up inside the sponge. By the time the like shrimp-looking guys reach adulthood, they’re no longer able to fit through the pores of the glass sponge that houses them, so they’re locked down with one another for life. Now that’s true monogamy in nature, people! The glass sponges that house this not so shrimpy couple are actually given as gifts to newlyweds in Japanese culture. I'm sure you can guess the symbolism in that!

For more facts on glass sponges, check out the links in the description. Give a thumbs up for strange animals and thanks for watching Animal Fact Files!