Tag Archives: Animal

The Mysterious Ninja Pigs

In the early 1930’s feral pigs were intentionally introduced to Santa Catalina Island. They became extremely abundant and were hunted by sportsman for over fifty years! They were also introduced to help control the island’s rattlesnake populations. After the population of these feral pigs began to skyrocket seemingly out of control, a pig control and eradication program began in the 1990’s. From 1990 till July of 2003, over 12,000 feral pigs were removed to help protect the island’s native species.


(Feral Pig – Sus scrofa )

The feral pigs were uprooting many of Catalina Islands’ fragile plant species. The rooting caused serious soil erosion, especially on hillsides. Not only were Catalina Island’s plant species in danger from the feral pigs, but some of the native species of animals were also at risk. Populations of golden eagles from the mainland were attracted by feral pig carcasses, and then decided to turn their sights to the islands’ endemic Catalina Island fox population. Although the feral pigs were declared eradicated from the island within the last decade, there is said to be one feral pig that remains…The Ninja Pig.

Many people have heard stories about the Ninja Pig and some believe that this pig is still on the island. They say that the pig has survived the eradication efforts and continues to live on the island. The Ninja Pig is known to be shaggy and large, with tusks. Evidence that there could still possibly be a pig on the island is the proof that people have found pig scat. Some people even claim to have seen the Ninja Pig themselves. There is only one question that remains…do you believe in the Ninja Pig?

Written By: Brooke Fox







Sheephead Transformation

Ever seen a fish cake before? This one might look a little unusual. It’s one of the most exciting fish to find on a snorkel (or as your birthday cake), called the California sheephead (Semicossyphus pulcher). Sheepheads can grow to be over thirty five pounds and a full three feet long. They can live over 30 years and they play an important role in marine ecosystems by eating sea urchins that might otherwise eat all the kelp.  However, their lifecycle is the reason why sheepheads often take the cake as most interesting fish. If you’re looking for a fish to satisfy your intellectual hunger, check out the California sheephead!

Sheepheads are all protogynous hermaphrodites, meaning they all start out female with the potential to morph into a male later on in life. When they hatch, juvenile sheepheads have bright red bodies with a white stripe across their body and black splotches on their fins. As they grow, the white stripe fades and the fins lose the black spots, becoming entirely red while their lower jaw turns white. A sheephead can have vivid colors like bright red or more subdued tones such as a pale pink. After growing from anywhere from six to twelve years, a sheephead can finally change into a male!

The change from male to female varies between individual fish. Usually a female can morph into a male when there are no other males living nearby (or not enough males) and she is the most dominant of the females in the area. Dominance can be established by big mouth competitions – two sheepheads will swim at each other while opening their mouths as wide as possible, sometimes even locking jaws. However, other factors can influence whether or not this change occurs, including where the sheephead lives, how large she is, how quickly she grows, when she matured, and the amount of fishing in the area. Sometimes, slower growing females will never change.  

If a female successfully starts morphing into a male, it’s no cakewalk. There are a couple changes she’ll experience. Her body colors adjust: her torso remains red but her caudal fin (tail fin) and head turn black, except for the chin. Talk about a five o’clock shadow! The fish also grows a large hump on the forehead. Finally, the sheephead’s reproductive organs change due to changing hormones. The ovaries reabsorb any eggs inside while transforming into testicular tissue. Then, the newly male sheephead can claim his own territory and begin life as a male!


Hamilton, Scott L., Jennifer E. Caselle, Julie D. Standish, Donna M. Schroeder, Milton S. Love, Jorge A. Rosales-Casian, Oscar Sosa-Nishizaki, 2007. Size-Selective Harvesting Alters Life Histories of a Temperate Sex-Changing Fish. Ecological Applications, 17(8), 2268-2280.

Loke-Smith, Kerri A., 2007. 15 California sheephead, Semicossyphus pulcher. Status of the Fisheries Report, 2011.

Love Milton.

Warner, Robert B., 1975. The Reproductive Biology of the Protogynous Hermaphrodite Pimelometopon pulchrum (Pisces: Labridae). Fishery Bulletin 73(2).

Shark Teeth 101

While shark teeth have long adorned the necklaces of ocean-inclined Homo sapiens, the true purpose of these aggressive dentures is all about getting food. However, being that there are over 400 species of sharks, one shark’s idea of a good meal might be very different from that of another species. Different shark species can have dramatically different teeth that reflect their dramatically different diets. The horn shark, a local bottom dweller that feasts upon bivalves, urchins, and crustaceans, has small flat teeth with which it crushes the hard-shells and exoskeletons of its prey. Meanwhile, the blue shark, a pelagic species that prefers squid and fish, captures its prey by piercing it with knife-like teeth. The list goes on and on: tiger sharks have serrated teeth for ripping the flesh of seals and other large prey, while whale sharks have reduced teeth that they don’t even use, as they eat plankton that they filter through their gills.

Shark teeth


Though shark teeth vary depending on the species, they all have one thing in common: they get lost… a lot. Shark teeth aren’t rooted into gums like human teeth, and so are much more prone to falling out when prey puts up a fight. For a shark though, loosing a teeth is no big deal. Unlike humans, which only go through two sets of teeth in a lifetime, sharks have no such limits and are continuously replacing their teeth. A single shark can loose thousands of teeth in its lifetime! Clearly, the shark tooth fairy is a far busier individual than the being that looks under our pillows.

shark teeth wow

Caption: A blue shark showing off his piercing, knife like teeth!


This continuous replacement of teeth is only possible because sharks, behind their teeth, have more teeth, and behind those teeth, are more teeth, and behind those teeth, are even more teeth, and behind those teeth… you get the idea. These backup teeth are arranged in multiple rows inside of a sharks mouth and work like a vending machine to push new teeth forward whenever the need arises. Depending on the species, a shark can have 5 to 15 to even 50 rows of teeth in each jaw. That’s quite the mouthful!

shark teeth horn

Caption: A horn shark displaying her small, dense teeth used for crushing!


Sharks are some of the ocean’s most successful predators, thanks in large part to their phenomenal teeth. The next time you’re around some shark teeth, whether sporting jewelry, sifting through a beach, or snorkeling with a living shark, remember that there’s much more behind each tooth than meets the eye.






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