Axolotl: Amphibian with a grin

The axolotl (Ambystoma mexicanum) looks like a fish, but it is actually an amphibian. Even though they have lungs and can survive on land, they most often use their gills to breathe underwater. If the water dries up, they can change (or metamorphose) into a life stage. 

Axolotl are known in part for their wide mouths (it almost looks like they're smiling!) and their ability to breath air. They also have feathery external gill stalks, which increase surface area for oxygen exchange.

This species is critically endangered due to habitat loss in the ancient waterways near Mexico City. But they are doing quite well at the Aquarium. Their comfy tank and special cart is often brought out for our live animal presentations where educators share lots more interesting facts about axolotl and answer your questions.


A Fresh Feeling: The Flooded Amazon Exhibit

Many people think about ocean animals when they imagine exhibits at the Aquarium — like sea turtles and stingrays and seals. But there are hundreds of freshwater animals at the Aquarium, too! Explore the teeming Flooded Amazon exhibit at the Aquarium and you'll see animals of all shapes and sizes.

The large window reaches almost to the floor, giving even the smallest visitors a great view of the exhibit. All the Amazon Rainforest exhibits together hold more than 4,500 gallons of water!

The Amazon rainforest is one of the most diverse habitats in the world. The forests, rivers and lakes are home to uncountable numbers of species, including animals and plants that have yet to be discovered. The New England Aquarium’s Amazon exhibits feature hundreds of live plants and life-like fiberglass replicas of gigantic rainforest trees, vines and termite mounds.


No Feeding Frenzy Today

While families pick over leftovers and some brave crowds in the shops, we wanted to share a nice quite moment of zen from the... piranha. That's right, those toothy freshwater fish from the Amazon!

Piranha are often associated with feeding frenzies (and we're not talking about the Thanksgiving dinner table). But here at the Aquarium you'll find them peacefully swimming through their Amazon Rainforest exhibit more often than not.

As we learned in this post, these red-bellied piranha (Pygocentrus nattereri) like to snack on insects, worms and small fish. They have been known to bark when there's competition for food, but most of the time they're very "well behaved"—as you can see in the video above!


Jellies have to eat

While friends and families across the country are preparing to feast on Thanksgiving favorites, let's take a moment to see how other animals eat. Even thought the Aquarium is closed for the day, Myrtle still gets to graze on squid and lettuce. The seals snack on herring, smelts and squid. Of course, the smaller animals eat, too.

Just because they don't have teeth doesn't mean that sea jellies don't eat! This video shows beroe jellies eating other jellies. Watch how they swim along and engulf smaller ones. Once in their "belly," enzymes and muscular contractions help break down the food. Beroe jellies have been known to eat other jellies nearly half their size!

Comb jellies are also noted for the cilia, or tiny arms, which propel the animal through the water. The constant wave motion of the cilia give off an iridescent sparkle. Come by the Aquarium this weekend, perhaps the twinkle of the comb jellies will put you in the holiday spirit!


Banggai cardinalfish: Very protective dads

There are thousands of marine animals around the Aquarium—some are small, some are shy and some have unusual lifestyles, at least by human standards.

Take the Little Banggai cardinalfish, (Pterapogon kauderni), for instance.

Banggai cardinalfish in the Aquarium's Living Corals exhibit

You can find this species in the “Living Corals” exhibit, (the tank closest to the Gift Shop on the first level). Native to the Banggai Islands of Indonesia, its good looks and ease of breeding make it a popular species in the aquarium trade. Popularity has also created a challenge for the species in the wild—it is currently listed as an endangered species on the IUCN red list.

Male Benggai cardinalfish carrying eggs in his mouth

This is a small, but elegant animal. Look for the fish that appears to be ready for a black tie event, with his black stripes and dramatically forked tail. He sports a sequined gleam and stylishly tasseled fins, sprinkled with decorative white dots. Practically speaking, the cardinalfish’s glamorous attire is suited to his life camouflaged amidst sea grasses, anemones and the long, black spines of the mildly venomous urchin, Diadema.

Follow the arrow to see the eggs sitting in this father's mouth.

Now look a little closer—he might not only be ready for a formal night out, he might also be ready for a visit to the maternity ward! If you see a fish with a distinctly larger jaw, you may be looking at a male brooding his young. He has a large oral cavity to accommodate the eggs and young that he nurtures attentively.

In fact, this father doesn’t need the maternity ward for help birthing; he does just fine on his own. You may see him roll the pinkish eggs to rearrange and oxygenate them. Once the eggs have hatched you may even see some tiny eyes peeking out when the male stretches his mouth. As the fry grow and are more difficult to contain, you might see a flurry of fins emerging from the male’s bulging mouth.

When his favorite food is presented in the exhibit, you may see him scurry—in the opposite direction! He doesn’t want to risk any of his young escaping his protection and becoming part of the food chain. In this way he protects his brood of up to 25 young for about 4 to 5 weeks, without ever taking a meal himself. Phew! After that, he might really need a night out!

The aquarists who take care of this exhibit leave a fry collector in the tank overnight in the attempt to catch these babies. We'll update you more on these efforts another time. Stay tuned!

– Lisbeth


New shark in the Tropical Ocean Exhibit

It's been quite an experience seeing the turtles, eels, reef fishes and rays from a whole new perspective in the Tropical Oceans Exhibit (that's what we're calling the penguin exhibit while the birds are relocated during the reconstruction of the Giant Ocean Tank). Now there's a brand new animal to observe, and he's a beauty.

The zebra shark (Stegostoma fasciatum) is easy to spot because of his size and bold spots. This male, named Indo, measures 6 feet long—3 feet of body and 3 feet of tail! That's pretty average for this species, although some have been measured at 9 feet. Indo hails from the Indo-West Pacific region, hence his name. His stout body has ridges on the dorsal, or top, side with yellow-brown spots. The juveniles have stripes more like the species' namesake.

Zebra sharks like to snack on mollusks, small fishes, crabs and shrimps. Here at the Aquarium, he's given a variety of seafoods, including capelin and squid (low calorie offerings) and shrimp (only as a treat or as an enrichment or training item, Indo loves shrimp).  He's fed 0.75 pounds three times per week to ensure the animal maintains his handsome physique.

Interestingly, this shark is part of an AZA breeding program, much like the penguins at the Aquarium. Indo was one of the first born to the program at the Shedd Aquarium in Chicago, then lived in Pittsburgh for many years. He has grown up in aquariums and was trained to feed using a target of a yellow circle. The aquarists do this by positioning a pole with the target circle in the water, indicating it’s time for the shark to station. Once the shark sees the circle and touches the target with his nose, he’s rewarded with some tasty morsels.

He's smart, he's handsome and Indo is an exciting new addition to the Tropical Oceans Exhibit. Come on by the Aquarium to see this stunning new addition for yourself!


Lionfish: An Unwelcome Guest

Lionfish (Pterois volitans) are quite lovely to watch, with their graceful fin spikes and stark brown and white bands. But don't be fooled, this fish is armed and dangerous! These residents of the Indo-Pacific were accidentally introduced into the Caribbean in the 1990s, and they are causing havoc on native reefs today. That's because lionfish are prolific breeders, have quite the appetite and no natural predators to keep the population in check. This invasive problem is quickly becoming one of the most important conservation issues in the world.

A long-time Aquarium volunteer and avid scuba diver Don Stark talked about the invasion of the lionfish on the Divers Blog. Don has taught many of our teen scuba diving students about this "prickly situation." (More on the students' encounters with lionfish here and here.) In fact, divers on the Bahamas Expeditions have been encountering these nasty predators in greater frequency. They've even sampled lionfish for lunch — turns out, they're quite delicious! Most recently, researchers have spotted lionfish in Belize.

Invasive species are a big problem all around the world. In the Phoenix Island Protected Area, rats threaten native bird populations. Comb jellies invaded the Black Sea and have wiped out some commercial fisheries. And today we're seeing lionfish muscle into Caribbean reefs, far from their native habitat.

Look for this dangerous beauty in the armored and venomous exhibit on Level 1. (Learn about another resident of this exhibit, the longhorn cowfish.)

One Big Fish: Goliath Grouper

Many visitors want to know where they can find the really big fish. Well, of course there are the tarpon and permits in the Giant Ocean Tank. But any discussion of really big fish at the Aquarium would be entirely incomplete with mentioning the goliath grouper. It's called goliath, after all!

A goliath grouper on exhibit in the Aquarium's Blue Hole exhibit

The goliath grouper (Epinephelus itajara) is one of 159 species of groupers living near coral reefs, rocky outcrops and even shipwrecks throughout the tropics. This large species can be found relatively close to home, living along the coast of Florida, through the Caribbean and the Gulf of Mexico, as well as the eastern part of the Atlantic. While many species can reach a few feet in length, the goliath grouper stays true to its name, growing over 8 feet long and 800 pounds during its 40 year lifespan. This makes it the largest grouper in the Atlantic!

Goliath grouper, photo: Albert kok via Wikimedia Commons

Though the Aquarium’s groupers are not nearly 800 pounds, they are still pretty impressive to look at. They seem even bigger once you see them in their Thinking Gallery home. Our goliath groupers can be found in the Blue Hole exhibit, located on the second floor of the Aquarium. Blue holes are cave formations that were once above water but were submerged over time. Though blue holes can be small and cramped, these solitary groupers love to live in these cozy, underwater caves and crevices. Known to be thigmotactic, groupers like to be in contact with a surface or an object around them and the tight quarters of the blue hole allows them to be in touch with the walls or other structures of the underwater caves.

Scuba diver with a goliath grouper at Dry Tortugas National Park, photo via Wikimedia Commons

In addition to being cozy, blue holes are a great spot to sit and ambush prey like spiny lobsters, shrimp, fish, octopus and young sea turtles. Since groupers don’t move around much, these holes provide a great home range where groupers spend most of their time, even protecting their territory by making an audible rumbling sound to warn other animals to keep away.

Our researchers have spotted goliath groupers in the wild in Belize! Did you know they can change from female to male during the course of their lifetime? Have you watched a neon goby clean their skin and mouth? Keep reading about these behemoths of the oceans and other residents of the Aquarium and our blue planet.

Everything octopus

The giant Pacific octopus is one animal at the New England Aquarium that most everyone wants to see. Perhaps it's their keen intelligence or their camouflaging abilities.

Or maybe you heard about a special event like when Octavia laid eggs, or when Truman squeezed himself into a box.

Or maybe you heard the Aquarium tale about the octopus that sneaked into another tank behind the scenes to snack on fish. Listen to aquariust Bill Murphy tell the tale here while interacting with George.

There's so much to learn about these fascinating cephalopods, and it's even more fun to see them in person! Stop by one of these days and get to know one of the most fascinating animals at the Aquarium.

A Wolffish Grin

In the dark corners of the Boulder Reef exhibit is a fish with quite a toothy grin. It's the wolffish (Anarhichas lupus)!

Wolffish are elongated fish may a face that only a mother could love, with a set of snaggleteeth that are replaced every year. But they are fascinating creatures. In 2011, several young Aquarium scientists traveled to the Montreal Biodome to study two species of wolffish: Atlantic wolffish and spotted wolffish. They were studying how the fish respond to stress, as one fish guest blogged about in this post (wink!), by sampling a tiny bit of the fish's blood. Read about the intern and graduate students' experience here.

Those teeth are sharp! An Atlantic wolffish bears battle scars from aggressive tank-mates at the Montreal Biodome.

As gnarled and grizzly as they may look, they are commercially relevant for their eggs (caviar) and meat. Consider how your seafood choices can help the oceans. Visit www.neaq.org/seafood.

All Things Lobster

Look beyond the dinner plate. You can find New England's favorite crustacean in the Gulf of Maine exhibit at the New England Aquarium!

American lobster (Homarus americanus) via Wikimedia Commons

Aquarium educators have a lot to share about these bottom feeders. For example, have you ever noticed that a lobster's claw are two different sizes and shapes? The thicker claw with rounded nubs on the cutting edge is called a crusher claw, used for crushing hard-shelled foods. The other is called the cutter claw. Thinner and pointier, it's used for gripping and ripping.

The blogs are also bursting with cool lobster facts and stories. Learn about the many colors in the lobster shell palette. Get a good look at one the heftier lobster to have called the Aquarium home. Meet one of the lobsters that greets visitors during live animal presentations. Even learn how lobsters in the wild communicate with each other (you'll never guess!).

A calico colored lobster! (Photo: Adam Clem)

Aquarium scientists recently made news with a story about lobster shell disease research. Learn more about the Aquarium shell disease research program. In addition to shell disease, researchers in the Aquarium's lobster lab are also looking into lobster nutrition, brain development and shell colors.

From The American Lobster: A study of its habits and development by Francis Hobart Herrick, 1895 (more here)

These amazing animals have long captured our interest and our taste buds. Find historical drawings from the late 1800's (like the one above) of lobsters in different stages of development. Learn about the long, bumpy history of lobster hatcheries in New England and around the world, and learn how the robust commercial fishery began.

The Language of Lobster

Communication across the animal kingdom is a seldom understood phenomenon (our right whale researchers are looking whale communication right now). While we know that most animals need to communicate with others of their species for various tasks, such as territorial dominance or mating practices, the exact processes are often still a mystery. In the case of lobsters, however, our understanding of their communication processes has increased significantly in recent years. So, how do these animals “talk” to each other? Well, to put it as simply as possible, they pee in each others' faces.

When lobsters urinate they are also releasing pheromones (or chemical smells) at the same time. There are a number of mysteries still involved in the production and dispersal of these pheromones, though. What is currently the most accepted theory involves nephropore rosette glands. In looking at the diagram below, you can see the lobster’s bladder is located under the brain. These rosette glands are connected to the urinary tract, so they can produce pheromones and then introduce them into the urine stream. American lobsters (Homarus americanus) release this urine from nephropores at the base of their large antennae (that’s right, lobsters pee out of their heads). Once released this urine is injected into the gill current produced by the lobster and this current projects the urine forward. It has been measured that lobsters can transmit urine signals up to SEVEN BODY LENGTHS ahead of them! That’s some pretty powerful urinary output.

Why does a lobster pee out of its head? A lobster’s claws, which are used for capturing prey and for defense, are located at the front of their body. Due to this, a lobster enters its shelter backwards so that its first and best line of defense is facing the main entrance to its home. Since it faces the opening of the cave, peeing out of their heads is the most direct route for the urine to reach the water around them.

In general, lobsters don’t really get along. If lobsters come into each others' territories then more often than not they’re going to fight; particularly if the lobsters are both males. They do this in competition for both the best shelters and for preferential mating rights. So where does pee come in? Well, once a dominant male has been determined he has to let any females know that he’s stronger. Since they probably didn’t see the fight something about the lobster needs to be different. The thing that seems to be different is the smell of their urine. What is actually different in their urine isn’t entirely understood, but it is thought because he is “happy” that he won he may produce more serotonin which then changes the scent of his urine.

As discussed previously, the dominant male in the area has a more attractive scent and the females actually come to him. The females approach the male’s burrow and proceed to pee in his face. That reduces his aggression and allows the female to enter his home. The female is allowed to remain in his burrow for up to two weeks before she must leave, allowing the next female in the area a chance to also mate with the dominant male. During this period of cohabitation the female’s urine is sending signals to other females that the male has coupled up.

You can look for American lobsters in the Aquarium's Gulf of Maine exhibit. You're likely to find lobsters of different colors, like blue and calico, although this cast of characters is always changing. There's even a hulking 21-pound lobster at the Aquarium! Meet a lobster up close during a Live Animal Presentation, the educator can probably answer you questions about the Aquarium's important research on lobster shell disease.

Hang on, it's the green sea anemone!

The green sea anemone may not be one of the most charismatic ocean animals. Of course, it doesn't play with garden hoses for fun like our young sea lions, and it doesn't put on shows for right whale researchers like that calf in the Bay of Fundy. But its vibrant colors and feats of strength make this tidepool resident worthy of a closer look!

Did you know that many of the specimens in this exhibit have been around for decades? These long-lived anemones thrive on the oxygen-rich water that crashes into the exhibit periodically, surprising some visitors. Just take a look...wait for it...

Video originally posted here.

As you can see, the anemones are well-adapted to living in the waves. Waves crush, abrade, and scour. In spite of this, plants and animals have developed special, often ingenious ways of coping. Sea anemones form attachments with a smooth, muscular disk on which they can slide very slowly. They can survive short periods of low tide exposure to the air by retracting their body and tentacles into a round, water-retaining mass. 

The animals in this exhibit hail from the Pacific northwest, like its giant Pacific octopus neighbor. The water is cold and rich with nutrients. You may also find sea stars, kelp, urchins and a few hardy fish in tidepools like this. In the wild, the abundant food supply in these tidepools and adjacent kelp forests also attracts sea otters and seals.

Compare the animals in this tidepool with those that you would find in tidepools around New England. Around here you might find rockweed instead of kelps, more mussels and crabs, smaller fish and fewer anemones and urchins. Come by sometime to see for yourself!

Goliath Grouper Fun Facts

There's a lot more to goliath group than mere size.

Groupers have a very interesting change in lifestyle: As they get older, they change from being a female to a male! As groupers grow, they are first female when they reach sexual maturity. After a few years, the female will transform into a male. Scientists believe that this transformation is triggered when the grouper is the right age, they are in a group of animals that are about to spawn and there are fewer males in the population. Once this change happens, it’s permanent.

What’s the advantage of having this life cycle? The energy-consuming task of growing eggs is left to the younger fish that are healthy and strong while the larger fish that have proven their ability to survive can fertilize the eggs as males. It's a good way to keep populations strong through genetics!

Groupers gather together in spawning groups once they are ready to mate. These groups vary in number, size, and location. Once together, the females lay eggs that float to the surface after being fertilized. The eggs then float with ocean currents for 40 to 60 days and arrive at the nursery grounds just as the tiny groupers hatch out. These small groupers swim down to the bottom of the ocean and hide in sea grasses and mangroves until they get larger, remaining in the nursery area for 4 to 6 years. Once they are large enough, the groupers then leave the nursery area and then move offshore to join adult populations in coral reefs.

Take a closer look: Visitors can watch neon gobies cleaning the groupers in this video.

Watch the groupers in the Blue Hole exhibit and you may see them getting a bath! Groupers rely on small cleaner fish to stay free of parasites and other itchy conditions. The small one-inch neon goby (look for the small black and neon blue stripes) is the fish for the job, removing loose scales and parasites from the skin and gills of the groupers. The groupers get clean while the gobies get a snack and protection.

Groupers are the dominant, top-level predatory fish on many coral reefs and help maintain balance among fish populations and increase the biodiversity in an area. However, these groupers face many challenges, including the destruction of mangrove nursery habitats and increased human activity along coastlines. The chief concern for the goliath grouper? Overfishing. These fish are caught as food but is hugely impacted by overfishing because of their reproductive behavior: when they gather in the mating groups, fishermen remove the largest groupers from the population. As groupers reproduce slowly, this practice leads to rapid decline. It’s estimated that the species has declined by 80% in just 40 years, causing them to be considered a critically endangered species. Though there are regulations in the USA, Caribbean and Brazil prohibiting fishing, particularly in areas of marine preserve areas which offer protection for groupers during their mating season, there is still concern that fishing and poaching in other areas continues, making the future of the goliath grouper uncertain.

Learn how you can make smart seafood choices to protect the oceans and animals like the goliath grouper here. Watch the groupers patrol their blue hole home here. And learn more about these


That fish is electric!

The electric eel (Electrophorus electricus) is a fish, and it's electric! These natives of the murky Amazon and Orinoco watersheds in South America use electricity to hunt for their next meal. Juveniles eat invertebrates, while adults feed on fish and sometimes small mammals. The fish can grow up to 10 feet (3 meters) with weight up to 44 pounds (20 kilograms).

Electric eels have wide mouths with one row of teeth, but the fish makes its living on electric shocks.

They generate strong electric shocks with specialized organs made of hundreds of thousands of electroplates, which are modified nerve or muscle cells that can produce electricity. Think of a battery. Low-voltage shocks help with navigation (just look at their tiny eyes, they're virtually blind!), while the high-voltage zaps have been noted during predatory attacks. The shock stuns the prey, while the electric eel is protected by a thick layer of insulation.

A visitor's picture of the electric eel at the Aquarium, photo by Steven G. Johnson via Wikimedia Commons

The next time you walk by the electric eel tank at the Aquarium, keep your ears perked for a crackling sound. That's how you know the eel is active. Every time it discharges electricity, sensors send a signal to the speakers above the tank. The speakers convert the signal into sound. Stronger signals produce louder sounds. When the eel is not hunting, the sound is quiet and infrequent. When the eel is looking for food, the sound is much louder and more frequent. When it's quiet, the eel is probably resting.

Electric eel, photo by opencage via Wikimedia Commons

All animals—including you—give off small amounts of electricity. This electricity is produced by the movement of the heart and other muscles. Electric eels use electricity in a different way. They can
store up a charge and direct it outside of their bodies to stun prey.


Rock out with the new guitarfish

This weekend New England Aquarium visitors have the chance to meet some special youngsters. In addition to the sea lion and fur seal pups, there are three beautiful guitarfish in the warm water exhibits on Level One. These fish are elasmobranchs along with other sharks and rays. Their skeletons are composed of cartilage rather than bone, kind of like your ears and nose.

Take a look. The Atlantic guitarfish (Rhinobatos lentiginosus) seem to be settling into their new exhibit quite well!

These fish can grow to be more than two feet long (76 cm)! They are bottom feeders, eating mostly mollusks and crustaceans. Atlantic guitarfish are considered near threatened by the IUCN Red List.
You won't find these fish soloing on stage in the spotlight, but it's not hard to imagine how they got their name.


Come visit this holiday weekend to watch these special animals in person!


Movin’ and Groovin’, Cowfish Style!

With so many great exhibits at the New England Aquarium, visitors often zoom through the building trying to see everything. However, once they start to slow down and look at the exhibits more closely, visitors can witness some pretty cool animal behaviors!

Located in the Tropical Gallery, the Armored and Venomous Fishes exhibit has some fascinating inhabitants. Striped lionfish cruise around with their long, venomous spines. Rockfish disappear into the background, blending in with the coral in hopes of surprising an unsuspecting prey. And the mover and shaker of the tank? The longhorn cowfish!

Longhorn cowfish in the Tropical Gallery

Native to coral reefs and sandy, muddy habitats of the Indo-Pacific, the longhorn cowfish is named for the long horns protruding from their head and below their tail. Those horns may look comical but they make the cowfish difficult to swallow, a pretty efficient way to avoid being eaten by large predators. And though the horns make break off over time, the cowfish will be able to grow them back in a few months.

Longhorn cowfish, Lactoria cornuta (Wikicommons)

Known for the horns as well as a scaly coat of armor, cowfish are not known for their swimming speed. No Olympic medals for these fish! Instead of moving their tail, or caudal fin, for propulsion, they use their dorsal (top) and pectoral (side) fins. Pretty cool! While using this method of swimming, the cowfish often looks like it’s hovering in the water, moving just slightly with a flick of those fins. 

Can you find all the fins? (Wikicommons)

While the cowfish in the Aquarium’s exhibit often moves with this method, one day recently he decided to kick it up a notch! With cameras rolling, the cowfish flicked his tail, moving it in some pretty quick circles! After he settled down, the cowfish went back to his normal swimming pattern. Take a look at the video and see if you can see the different fins helping to propel this fish along.

So next time you are in to the Aquarium, slow down for a bit and and stop to watch the animals. You never know when you might see a fish movin’ and groovin’ inside the exhibits!

If you liked this video, check out video of the flashy mandarinfish or brace yourself for the surprise in this clip.


More eggs: Goosefish lays another egg veil!

You may recall that our lovely goosefish usually lays an egg veil once a year. You can see pictures and video of this special event here, here and here. But it's once in a blue moon that she lays TWO egg veils in the year. This is just one of those times.

The last time she laid an egg veil was in May. While one might expect this one to be a bit smaller, it's actually about the same size as the last one. So come visit the Aquarium this weekend and look for this exhibit on the third level. Take a moment to watch this fabric-like sheet sway and flow throughout the exhibit's gentle current. There's a good chance that you'll walk away being amazed and a little more relaxed. It's truly a beautiful sight.

And don't forget to look for the goosefish! She'll probably be nestled into the gravel on the bottom of the tank. She might be fishing with her modified dorsal fin, trying to entice a fish into her enormous mouth. Or she might just be resting after all that hard work laying the egg veil.


Octopus Eggs on Exhibit!

Though summer has officially started on Central Wharf, there are still plenty of spring-like behaviors going on around the Aquarium. While we recently had a pretty impressive egg display from our goosefish, just two tanks down to her right is another interesting egg event! Octavia, our current giant Pacific octopus, has laid eggs!

Octavia looking lovely in her exhibit.

Octopus are pretty fascinating animals. They are extremely intelligent and incredibly elusive. They are also somewhat prolific. Octopuses spend the majority of their life alone, but there is one time when two octopus will come together. Octopus mating is a pretty big deal – since it only happens once in their short, 3-to-5-year lifespan!

A wild octopus guards her eggs in Puget Sound. Photo: JBruels

The average giant Pacific octopus female can lay up to 100,000 eggs in long sticky strings attached to hard substrates, with some estimates claiming only a 1 percent survival rate in the wild. It’s difficult to tell how many survive, however, because octopus populations are not well studied or documented in the wild since they are cryptic and hard to locate.

A few octopus eggs are on the glass of the Aquarium's exhibit, the rest are attached to the rock surface near the window. Each egg is about the size of a grain of rice.

Since we only have the one octopus, our eggs are not fertile – but they are plentiful! In our exhibit, there are some eggs attached to the glass and the rock-surface near the window. However, the majority of her eggs are located in the upper left corner on the wall behind Octavia’s usual hiding spot.

So, next time you’re in the Northern Waters Gallery see how many of these eggs you can spot!



Something new in Ancient Fishes

Visitors to the Aquarium may have noticed the new Ancient Fishes tank in the Thinking Gallery. It’s a pretty impressive tank and it’s nice to have some of our old residents back after this recent upgrade.

In addition to returning friends like the freshwater rays and the gars, there are also a few new species on display. Some of the most charismatic of the newbies are the two species of elephantnose fish (also known simply as “elephantfish”). Have you seen them!?

Elephantnose Overview
Elephantnose fish are in the order Osteoglossiformes, the sub-order Notopteroidei and the family Mormyridae. There are an estimated 200 species in this family ranging in sizes from 5 cm to 1.5 m. While not all species have the characteristic trunk-like appendage, they all have the ability to generate a weak electric field to help navigate their turbid environments.

We have two separate species in the Ancient Fishes Exhibit here at the Aquarium. The vast majority of the large school are known as Peter’s elephantnose (Gnathonemus petersii) and there is one specimen of the longfinned elephantnose (Brienomyrus longianalis).

Peter’s Elephantnose (Gnathonemus petersii)

Photo: Jacque Moreau via fishbase

Habitat: Rivers of west and central Africa - prefers muddy, slow moving rivers with cover
Size: Averages 23-25 cm in length
Diet: Insects and worms
Life-span: Estimated at 6-10 years
Peter’s elephantnose have the elephant trunk-like protrusion. While their name implies it is their nose, it is actually an appendage attached to their lower jaw. This sensitive apparatus is known to be used in communication, self defense, navigation and for locating prey.

Longfinned Elephantnose (Brienomyrus longianalis)

Photo: RMCA via fishbase

Habitat: Similar to that of Peter’s elephantnose
Size: Approximately 16 cm max length
*There is far less known about this species
Unlike Gnathonemus p., the longfinned elephantnose does not contain the trunk-like appendage implied by their name. In addition, while the Peter’s elephantnose’s anal and dorsal fins are equal in length, the longfinned elephantnose gets its name from the anal fin, which is much longer than its dorsal fin.

Elephantnose and the Electric Eel – A Story of Convergence
What do elephantnose fish and electric eels have in common? No, not just that their names are both fairly misleading, they also both emit electrical fields to sense their environment and locate prey. This is a fascinating example of convergent evolution – two unrelated animals developing similar adaptations over time.

The elephantnose fish have a brain to body size ratio similar to that of humans! Much scientific research has been dedicated to study how elephantfish use weak electric fields to sense their surroundings and possibly to communicate. Perhaps their cerebellum is so enlarged to help them interpret bio-electrical signals. [We recently posted about a new exhibit that shows how whales and dolphins communicate and navigate their surroundings! Check it out.]

While these species of elephantnose are themselves species of least concern, they share their freshwater habitats with other species in need of our protection. River habitats in Africa face many of the same issues as rivers all over the world (pollution, damming, overfishing, etc) so these fish can be used to inspire each of us to think about how our local actions impact global ecology.