a rift

Exploring a chamber of secrets

montereybayaquarium:

Do you know what a baby nautilus looks like? Do you want to see what a baby nautilus looks like?
Squee! Chambered nautilus are hatching at the Aquarium!!
As a second grader, seven-year-old Ellen Umeda charted her hopes and dreams in a journal, including this entry:
“When I grow up, I want to work at the Monterey Bay Aquarium.”
Today, Aquarist Ellen Umeda is doing just that – and breaking new ground as she raises one of the most challenging species housed at any aquarium: the chambered nautilus.The Sunnyvale native and UC San Diego graduate is taking the lead in caring for our first-ever chambered nautilus hatchlings, and trying new approaches that could someday lead to a breakthrough in raising and breeding these beautiful, shelled cephalopods. “I’m lucky to be working with an animal that’s still quite a mystery,” Ellen said. “There are so many unknowns.”
Nautilus eggs! You’re looking at em! WHOA! Did that one move?
No one, for example, has seen a nautilus egg in the wild – perhaps because they’re laid at depths beyond where recreational scuba divers can safely go. They can range below 100 meters (330 feet deep) – but do the young develop in warmer waters, closer to the surface, or in cooler, deeper waters?
These are some of the unknowns Ellen has to contend with as she tries to take the rearing of chambered nautilus beyond the point her colleagues have achieved.
Wheee! After developing for over a year, a fully-formed nautilus emerges—with a little yolk left over.
As a member of the team that cares for the animals in our Tentacles special exhibition, Ellen raises many of the species we exhibit, including cuttlefishes and squids. She and her teammates have built a successful track record with species that no other aquarium had raised before.
Chambered nautilus present an entirely new set of challenges. She’s been wrestling with those challenges since the first nautilus egg hatched in late July. Several others have hatched since then. Starting in the 1980s, colleagues at Waikiki Aquarium, Omaha’s Henry Doorly Zoo and Aquarium, and Birch Aquarium in La Jolla began hatching and raising chambered nautilus they kept on exhibit. None of the hatchlings survived much more than a year.
Toba Aquarium in Japan has also had success hatching nautiluses, with a few individuals surviving three years or longer – including one individual that lived four and a half years.
Time for noms!
Ellen is drawing on the experience of colleagues at other aquariums, and the resources here in Monterey, to seek a breakthrough in chambered nautilus care.
She’s now caring for more than 150 nautilus eggs, and fewer than a half-dozen hatchlings. They’re housed under low-light conditions, some in cooler water and some in warmer, in behind-the-scenes holding areas. She’s experimenting with the water temperature at which she’s keeping the eggs laid on exhibit by the adult nautiluses. And she’s working with Curator of Collections Joe Welsh, who’s pioneered the use of pressurized holding tanks for deep-water species.
Yeah, I’m adorable and my adaptations are awesome.
Ellen believes raising chambered nautilus under pressure – perhaps even putting eggs in a pressurized aquarium before they hatch – could be the key to solving the problem of the young nautiluses becoming buoyant in the water column, rather than neutrally buoyant and able to maintain their position in the water. She thinks that the fluid-filled chambers that develop, section by section, in a growing chambered nautilus, may not function properly unless they form under pressure.
“Some of my colleagues thought that might be a solution, but they didn’t have the resources to pursue the idea,” she says. Here, she noted, we have a track record of success with deep-water rockfishes that may point the way forward with chambered nautilus.
Bless you!
“We need to experiment and try different things that mimic their environment in the wild, things that other people haven’t done,” Ellen says. “I hope our animals will live longer, and that a greater percentage of them will hatch and survive. The ultimate goal would be to raise them to adulthood, have them lay eggs, and then raise the next generation.” That, she admits, is probably a long ways off. Just as she’s benefited from the experiences of her predecessors, she hopes to contribute the next increment of progress.
“It’s all steps,” Ellen says. “Right now, it’s live one more month, and then one more.”
Ready or naut, the Year-End Sea-lebration continues with our first ever baby nautilus hatching at the Aquarium!