4 Dec 2010 - What IS a Salp???

You are probably wondering,….what are those scientists so riled up about down there! What IS a salp? Let me tell you: salps are awesome!!!

A typical salp.

So they may not look like much, but if you dive a little deeper into their natural history, you will become intrigued. First of all, while they appear to be just a small lump of gelatin, salps are indeed animals! They can swim (slowly) by propelling water through their bodies and are constantly feeding (just like I wish I could be…). They eat by creating a mucus net, allowing it catch food particles floating by, and then ingest the net full of particles!! Genius. They will eat pretty much anything entrapped in their net if it is between 1µm to 1mm in size. The red / orange blob is their coiled intestine.

Here are some salps we recently caught in a net tow.

You probably are wondering, what eats these guys? Lots of things do! Certain fish, amphipods, krill, and some other zooplankton may chow down on a salp if they find one. Delicious!

Another reason why salps are both awesome and related to your life back at home is their impact on the global carbon cycle. Because they consume food quickly and there are so many salps in the oceans – they have a significant role in the vertical carbon flux. Downward carbon flux, such as towards to the sea floor, is great because it removes carbon from the upper ocean which in turn removes atmospheric carbon dioxide. Salps do this by producing large (1 to 10mm long) fecal pellets chock full of carbon. The pellets are denser than sea water and rapidly descend into the depths.

Salps also have a very interesting sex life. They are found in both solitary / individual form (alone) or in an aggregate / chain group. The solitary forms reproduce asexually, which means the “babies” are clones of themselves. The offspring are produced in a chain which can be hundreds of salps long! They are released from the parent in chain form; this is known as an aggregate group. The group of young salps work together to swim and feed, and the chain grows. Each individual is known as a blastozooid. Some of the blastozooids will reproduce sexually; and a new baby salp (embryo) will grow attached to the body of the parent. Eventually, this baby is released in the solitary form, and will grow and reproduce asexually, bringing everything full circle. Can you imagine if we grew like that?

Because of this remarkable reproduction cycle, salps can grow very quickly!! One generation can be as short as 50 hours.

Scientists believe that salps have one of the first occurrences of a primitive nervous system. More complex nervous systems, such as ours, likely evolved from salps! That’s awesome!

Remember, a salp in the hand is worth two in the sea!!

Stay tuned to learn more about our Salp studies!

Signing off,

Katie.