Some animals reproduce pretty routinely in aquariums. But it's extremely rare for a nautilus. So imagine the surprise of our staff and volunteers when they spotted not one, not two, but three bouncing baby nautiluses while cleaning the Deep Pacific Coral exhibit.


The nautilus belongs to the cephalopod family (along with the squid and the octopus), and it's sometimes called a living fossil because it has evolved relatively little over millions of years. It lives in water that's nearly 1,000 feet deep, so its exhibit is kept very dark, making it even tougher to spot the babies, which are only about 2.5 or 3 cm (about 1 inch) long.

The photo at the top shows what an adult nautilus looks like, and the photo below shows one of the babies alongside an aquarist's hand.


Read this blog post to learn more about the nautilus and to see a video of the unusual way the nautilus moves.

There’s always a surprise at the New England Aquarium, as one young lady discovered at the West Coast Tidepool exhibit in the Northern Waters of the World Gallery. Take a look, it's worth the wait!



Tidepools are found at the water’s edge along rocky coastlines. Organisms have developed unique biological adaptations to survive powerful forces such as pounding waves and extreme temperature changes. They must be able to hold tightly to rocks and survive for periods out of water. In this exhibit, a simulated wave breaks regularly, aerating the water and delighting surprised visitors.


Sea anemones are most prominent in this tank. You may also find kelp, sea urchins and a few hardy fish. The abundant food supply in tidepools and adjacent kelp forests also attracts sea otters and seals.



The bat star’s name comes from the joined area between its arms, like the webbing between the bones of a bat’s wing. This adaptation may help the bat star withstand the force of crashing waves.

Bat star (photo: Jerry Kirkhart, via Wikimedia Commons)

Now take a moment to compare this tidepool from the West Coast to some you find around here, where you would find rockweed instead of large kelps, more mussels and crabs, smaller fish and fewer anemones and urchins. What might you find here at the Edge of the Sea tidepool touchtank here at the Aquarium? Come by sometime and have fun exploring tidepools from near and far, right here in downtown Boston!

Visitors to the Aquarium can often spot educators throughout the building toting a biofact — like a shark jaw, shark skin or a whale vertebra. Our educators are always poised to answer questions, and they might even teach you something new about our aquatic world.


Let's take a moment to talk about one of these special teaching tools: The whale vertebral disk. It probably came from a large baleen whale, up to 55 feet long. The giant bone was brought up by fishermen trawling for scallops on Stellwagen Bank in the late 1960s (before the Marine Mammal Protection Act of 1972). It is very similar to the disks between the vertebrae of a human spine, although whale bones are more porous and, of course, considerably larger! When the whale was alive, the holes were filled with oil, which helps with buoyancy. Being more buoyant helps the whale reach the surface to breathe.

 

After hearing the history of this bone, many people ask about trawling. Bottom trawling involves dragging large, heavy nets along the sea floor. Large metal plates and rubber wheels attached to these nets move along the bottom and can capture or crush nearly everything in their path. The nets can also level the structure of the bottom, destroying important habitats for benthic (or bottom-dwelling) organisms. This had been compared to clear-cutting a forest. This whale disk was part of that benthic structure and may have provided shelter for other animals. When it was pulled up in the fishermen’s net, it was covered with algae, barnacles and other small animals.

Currently, fishermen are experimenting with new methods of trawling that should help to prevent benthic degradation and avoid bycatch. In fact, the Aquarium is working with fishermen, engineers and marine biologists to research and develop fishing techniques that reduce bycatch of endangered non-target marine species. Learn more about these efforts on our Conservation and Research pages.

Juvenile right whale skeleton at the Aquarium

The next time you're at the Aquarium, keep an eye out for an educator with this important biofact. Try looking up, too. Check out the right whale skeleton hanging from the ceiling. Can you find the vertebrae? How many are there? How many do you think people have?

You never know what you're going to learn during a trip to the Aquarium, or a troll around our blogs.

This is Part II of a series of posts about eggs laid in The Trust Family Foundation Shark and Ray Touch tank. See pictures and learn more about shark egg cases in this previous post.

The green sea urchin (Strongylocentrotus droebachiensis) comes from the class of animals called  Echinoidea, which means "like a hedgehog." Can you guess why?

Green sea urchin at the New England Aquarium

Young hedgehog (Photo: By Calle Eklund/V-wolf, via Wikimedia Commons)

Sea urchins are related to sea stars, sand dollars and sea cucumbers. You can find urchin species in oceans around the world (and in the Edge of the Sea Touch Tank here at the Aquarium!). The green sea urchin prefers shallow, rocky areas. They snack on algae and dead matter by scraping with five pointed teeth.


Urchins can destroy kelp beds and are sometimes seen as pests! An urchin's mouth structure is also called an Aristotle's Lantern. It contains the five teeth and also has 40 different skeletal parts and 60 muscles.


Urchins can move at a rate of six to seven feet per hour. They use their spines and tube feet, also called podia, to get around. Each spine is attached with ball and socket joint.

 Look closely and you can see the podia in this picture.

Podia are long and slender with terminal suckers at the end. Tube feet operate hydraulically by means of a water vascular system.


 Urchins often cover themselves with pebbles, shells, and bits of seaweed for camouflage.

Sea urchins have a long list of predators, and people are tops on that list. Marine birds, arctic foxes, sea otters and starfish also eat urchins. Wolffish swallow urchins whole. Triggerfish blow them over with a jet of water. Gulls pick the urchins from a tide pool, fly overhead, and drop the animals onto the rocks. The shell breaks open on impact and the gull flies down for its meal.

 Group of green sea urchins in the Aquarium's Edge of the Sea exhibit

Conservation Notes: Sea urchin roe (actually both the male and female gonads), called uni in Japan, is considered a delicacy. During the "Green Gold Rush" of the 1980's and 1990's, millions of pounds of urchins were harvested for their roe. Overharvesting amid a lack of regulation caused the urchin population to crash. Regulations now prevent overharvesting of urchins, but populations have been slow to recover.

On your next visit to the Aquarium, look for a sea urchin at the Edge of the Sea touch tidepool. You can also see urchins in the cuttlefish exhibit and the Northern Waters gallery.