Text: Grethe Hillersøy
Photo: Grethe Hillersøy & Tony Meyer
One beautiful day in late October, western coast of Norway. I decided to go out for a snorkel. The aim was to discover and map a bay that may be of interest for a snorkel trail that we are working on.
The summer was over with all its frantic action for every creature in nature to reproduce during the short nordic summer months. Life slows down also in the ocean. Animals move slower because of the lower temperatures, many migrate deeper to avoid the cold surface temperatures, and some die after having fulfilled their life’s purpose during the summer. Not much seemed to be going on.
So I jumped into the cold water and was amazed at the numbers of starfish larvae in the water. We had been diving in the area for a week, and only seen the odd larva around. Today it was like swimming in a soup of starfish. It was incredible!
Unfortunately I had only brought my new compact camera (Sony RX100) which I’m still learning how to use, and the pictures are therefore not great. But you do get an idea of how many there were! I didn’t spot many that had settled, except in a small crevice where they had gathered in their hundreds.
In early spring millions and millions of tiny starfish larvae were spawned into the ocean. There they took up a planktonic life style, drifting at the surface, wherever the currents may take them. Slowly growing larger. By late autumn they have grown to the length of 1 cm, and look like a minute starfish attached to a long, gelatinous mermaid tail. The tail flaps from side to side, keeping the starfish from sinking. The starfish are now ready to settle on the seabed. They therefore drop off the tail, and sink down. The larvae are of the species sand star Astropecten irregularis, a star fish that lives at a depth of 10 meters or more.
The next day we brought our bigger cameras to the same bay, but could not find one single larva. The currents and tides had aggregated them there for just one day. That is why wild animals are so exciting to look for. There are no guaranties, and that makes it a lot more exciting when you do find them! The key to finding them is therefore both to know when to look for them, but also to spend a fair amount of time in the water. And you do not need to go diving as they aggregate at the surface. All you need is a warm suit of some kind, and a mask and snorkel.
The larvae may not seem like a very tasty or nutritious catch for another animal. However, the Dahlia anemones Urticina felina were happy to have them on their menu this autumn day. Look closely at this anemone, it is about to devour two starfish larvae at the same time.