Oct 11, 2023

Hampton Beach NH Oceanarium welcomes spiny, spiky and hungry sea raven

Thanks to Normandeau Associates in Hampton, we have a new addition to our main tank this summer. They collected a tiny juvenile sea raven just outside the harbor.

It is another fish that only a mother could love, but in all of its ugliness, it is adorable.

I assume this sea raven was about 6 to 8 months old when it arrived. They have a body covered with prickly spines and fins with bulbous loose extensions that look like seaweed when resting on the bottom. With their mottled skin and frayed fins, they are experts at camouflage. Their mouth is huge and wide, and lined with rows of very sharp teeth that allow them to feed on just about anything they please! They munch down on clams, crabs, lobsters, sea urchins and even other fish, anything they come across on the bottom amongst the rocks.

Our sea raven has been eating more than its weight in chunks of whiting and anything it can scrounge in our tank, which includes any of the amphipods and ghost shrimp that he can scoff up. He does attack them with a vengeance. The other day he all but swallowed the forceps holding his food before I had it halfway into the tank.

Our sea raven spends its days quietly sitting on the bottom of the tank, trying hard to look like a rock with seaweed attached. When you least expect it, it darts towards some prey, mouth open, and swallows it whole.

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In the month it has been in our tank, it has more than doubled in size. At this rate, we will need to release it back into the harbor before the end of the summer, or I suspect we will be missing a blue lobster!

According to "Fishes of the Gulf of Maine" by Bigelow and Schroeder, they can grow to 19 inches and 7 pounds.Sea Ravens have a unique way of spawning. The females carry between 15,000 and 40,000 eggs in a breeding season. During this time, the males become brightly colored and go through a mating dance culminating in the male transferring sperm to the female internally. This is different than many of the fish in the Gulf of Maine, such as cod or haddock, where the males fertilize the eggs externally after the females lay them on the ocean floor. The eggs of the sea raven are large, up to 4 millimeters and very sticky. While inside the female, the sperm stick to the egg but do not fertilize it.

Fertilization takes place as the female lays the eggs onto the branches of finger sponges on the ocean floor. It appears that the females do not lay all their eggs at once but spend the entire season laying clumps of eggs on various sponges.

Sea ravens are seen throughout the Gulf of Maine but prefer the rocky bottom down to 300 feet. They also prefer very cold water and can survive down below 30 degrees Fahrenheit. They shy away from the warmer water of the coastal areas in the summer, preferring water colder than 50-60 degrees. So, our little friend would probably have migrated out into deeper water for the summer. We will make sure it's released in the appropriate temperature. Our tanks are kept at the perfect temperature for the raven at about 41 degrees Fahrenheit.

Many fish that survive in colder waters and in the Arctic produce an "antifreeze," which allows them to survive in below-freezing temperatures. Unlike the antifreeze used in our cars, which is alcohol-based, this antifreeze is based on amino acids. Sea ravens have a unique amino acid unlike those found in other fish, according to an article in the Journal of Biological Chemistry by Don Slaughter.

According to "Fishes of the Gulf of Maine," sea ravens are tasty table fish. I’m not quite sure how this is possible as there is very little meat on them, and I couldn't imagine trying to fillet one. They do make great lobster bait and unfortunately for them, are caught in traps trying to eat the lobsters. They often end up as lobster bait. I guess there is some kind of justice. They eat the lobster, and the lobsters eat them. All is fair in survival! We will keep a close eye on the tank here at the Oceanarium and ensure that both the lobsters and the sea raven are well-fed and don't decide to munch on each other!

Ellen Goethel is a marine biologist and the owner of Explore the Ocean World Oceanarium at 367 Ocean Blvd. at Hampton Beach.