The Aquarium Hosts a Slugfest

There’s a bit of a slugfest taking place in the new Secret Lives of Seahorses exhibit, but it’s not what you think. The Pacific seahorses are sharing their exhibit with the enigmatic sea hare (Aplysia californica ) and the brightly colored navanax (Navanax inermis). Monterey Bay Aquarium husbandry staff were on a seahorse collection trip in southern California when they noticed an  abundance of both animals, so they “thought it was only appropriate” to include them in the popular exhibit, says aquarist Lindsay Parker.

Speedy Sea Hares
From their bulky appearance, you might think that sea hares are slow. Not so, says Lindsay. “They really cruise—they do laps. They’re named ‘hares’ for their ear-like appendages, but I could argue that it’s because they’re so fast!”

 

The sea hares have been busy, too. One day the aquarists came in to find yellow, filament-like strings dangling from plants in the exhibit—one of the sea hares had laid thousands of eggs.

 

Sea hares can live to be three years old, grow to 16 inches and weigh 30 pounds. (One Aquarium specimen reached 14 inches.) The two in the seahorse exhibit are now about seven inches long. And although they look substantial, Lindsay says that when she handles them, “it’s like picking up a puddle—there’s nothing to them.”

 

Sea hares have some interesting traits. When threatened, they can release a cloud of purple “ink.” They’re also hermaphroditic—in other words, they can be male or female. “They’ve got both parts,” says Lindsay.

 

Neon-colored Navanax
The smaller navanax is recognizable by the almost fluorescent, blue and yellow lines along the length of its body. A common defensive tactic, these colors tell predators that the navanax makes a poisonous meal.

 

The navanax shares many traits with the sea hare—these animals are both male and female simultaneously, and lay eggs in brown, string-like filaments. Unlike sea hares, the navanax’s preferred diet is small olive snails, which it eats with distinctive style. It has a skin-like “hood” that comes out of its mouth and gobbles the prey in one big gulp.

 

Surprisingly, these intriguing animals are making great contributions to brain research. They’re often used in neuron-science studies because their nerve cells are large and more conducive to study. Sea slug research has resulted in advances in everything from mental retardation to Alzheimer’s.

 

Comments

[Cruise Deals]

The Navanax look amazing!I mean - no offense to the Sea Hares but they are so colorful and fascinating! I love sea horses! But these guys are so fascinating as well!

[Fish Tanks]

Interesting looking creatures!