On Exhibit: Kelp Forest
sponges, coelenterates, bryozoa, worms, nudibranchs
to 14 inches long
Monterey Bay to southern Baja California
At the Aquarium
Behind-the-scenes with a feisty fish
"Garibaldis are a great fish—really cool, very personable, but very aggressive," says aquarist Scott Reid, who has managed the Aquarium's Kelp Forest exhibit since 2001. The same five fish have shared the exhibit since 2008, finding just enough room to live amicably. "If you hit a certain point where you have more garibaldis than territory," Scott says, "they'll start to fight it out."
As long as they're not fighting, garibaldis are easy to care for. "They're really tough and hardy—not a fragile fish by any means," Scott says. They get much of their food by grazing on algae or sponges growing in the exhibit, occasionally joining the feeding frenzy when a diver offers krill during an afternoon feeding show.
Fiercely territorial, our garibaldis have been known to take offense when an aquarist gets too close. "They charge you and they make a grunting noise, kind of like someone making a burp," Scott says. "At first you don't know what it is, and then you put two and two together and you realize you're being charged by a garibaldi."
Because garibaldis are uncommon around Monterey, the Aquarium staff heads down to Santa Catalina Island ("garibaldi central," according to Scott) once a year to look for new additions. "We go down in September when the water's warm," he says. "They're so numerous and so bright that you can see them from shore."
A fish with attitude
Garibaldis are round, plump fish with flowing pectoral and tail fins, and staring yellow eyes. Swimming through dark reefs and brown kelp, they're a jolt of glowing orange, a reminder that garibaldis are relatives of coral-reef damselfish. Juvenile garibaldis are deeper orange, with sparkling spots of blue and blue-trimmed fins. These vividly colored fish are extremely territorial, and have even been known to charge our aquarists.
They occur as far north as Monterey Bay but are especially common in the warmer waters of Southern California and the Channel Islands. Up to 40 garibaldis, and their territories, can exist within an area the size of a basketball court.
The fish eat sponges and algae that grow around their rocky homes as well as small animals such as tubeworms, nudibranchs and bryozoans. Their diet of sponges may contribute to their bright colors.
A tidy patch of algae
Much of the work of raising babies is handled by the male. Upon becoming an adult, a male garibaldi picks out a promising stretch of reef—a sheltering nook plus a smooth expanse of rock wall—where he will live for the rest of his life.
Each March, males work feverishly to tidy their nest areas, by removing debris, carrying away sea stars or urchins that wander along, and biting away all the plant growth except for a few species of red algae. These he trims so they're about an inch long—perfect places for thousands of eggs to rest.
Loops and throat-thumping
Once a male's nest is perfectly trimmed, the next challenge is attracting the attention of female garibaldis. Beginning in April and lasting until fall, females ready to lay eggs make outings to look for good nests.
They signal their interest by swimming with their fins sticking straight up. Males try to entice these females over by swimming loops with their bright orange bodies. At the same time, they thwack together the teeth in their throat to make a thumping sound that (they hope) the female can't ignore. If she takes notice, he swims straight over to his nest, hoping she will follow. Females are very choosy, often visiting 15 nests or more before making up their minds.
In the end, it seems to make little difference how well tended a male's nest is or how well he swims loops. Females are reluctant to lay their eggs in an empty nest—they look for a nest with eggs from at least one other female (and up to 20 females). This means male garibaldis have to work hard to attract their first females; after that, many others come—sometimes lining up to lay eggs at a popular nest.
Females are also picky about the age of the eggs in a male's nest. They prefer to deposit theirs alongside other freshly laid, bright-yellow eggs. Garibaldi eggs hatch in two to three weeks, so eggs with just a few days' head start would hatch earlier and have an advantage over younger hatchlings. In a bizarre turn of events, males sometimes eat the older eggs in their nests (gulping down 200 at a time), gambling that they'll attract even more females in the next day or so.
Trespassers will be bitten
Male garibaldis are fiercely protective of their territories and they don't get sentimental after attracting a mate. As soon as a female has laid her eggs, the male chases her away before she has the chance to munch on any other eggs in his nest, then fertilizes the eggs by scattering his sperm over them. He also chases off any other creatures that venture too close, including divers.
Garibaldis have a clear idea of exactly where their territories end, and two males may be seen peacefully grazing less than two feet apart—as long as each remains on his own turf. Female garibaldis tend to be less protective of their territories, perhaps because they contain no eggs. Territoriality seems to be tied to the rocky reef—periodically, garibaldis gather without drama in the waters above the reef. These "kelp socials" seem to be a way for garibaldis to investigate each other and may help females choose their mates.
What's in a name?
In the 1840s, an Italian named Giuseppe Garibaldi decided to start wearing bright-red shirts as part of his personal style. He went on to fight for the reunification of Italy, became a general and died a national hero. So when biologists discovered a brilliant red-orange fish cruising the rocky reefs of California—one that sallied out to bare its teeth at any intruder—they knew exactly what to name it.
Garibaldis have a restricted range—they're found from Baja California to Monterey Bay and nowhere else in the world. Within that range their populations are stable. They are especially numerous in Southern California's warm waters and much less common around Monterey.
Because of their appealing looks and bright colors, garibaldis are popular aquarium fish, but it's illegal in California to collect them or keep them without a permit. The garibaldi is the state marine fish of California.