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Rainforests of the World 

March 27, 2011

New Ricefish Species on Display

Below is a photo of one of my absolute favorite exhibits here at the Academy, our 400-gallon southeast Asia community display:

Photo by: Rachael Tom

Hundreds of small, colorful and peaceful fishes call this tank home, including a brand new and quite rare species of ricefish, Daisy’s ricefish Oryzias woworae. The ricefishes are a family (Adrianichthyidae) of small fish that are found in fresh and brackish waters from India to Japan and out into the Indo-Australian Archipelago, most notably Sulawesi. The fact that many species are found in Japanese rice paddies gives this group of fishes its common name.

Named after Indonesian crustacean expert Daisy Wowor (who collected the fish), Daisy’s ricefish was collected from a freshwater stream on Muna Island, off the southeastern coast of Sulawesi in Indonesia in 2007 and was just described last year!

Photo by: Rachael Tom

The Academy currently has about 30 of these rare fish on display in the rainforest. These beauties are about an inch long and can usually be seen schooling together. They can be identified by their remarkable color pattern of a steel blue body (in males), highlighted with brilliant red stripes on its abdomen, pectoral fins and caudal fins. They also have striking, iridescent blue eyes which are very visible against the slightly murky, sediment-laden water of the exhibit. Our specimens are doing wonderfully and, if you’re lucky, you might see a female carrying eggs attached to her body between the pelvic fins. This unusual method of spawning is thought by some to be an evolutionary precursor to internal fertilization and, even, livebearing.

Sulawesi is a unique center of global biodiversity that has very high numbers of species found nowhere else in the world. This is in part because it is tropical and made up of many islands and, in part, because of a complex geological history. In addition to countless endemic species of birds, mammals, reptiles, amphibians, invertebrates and marine fishes there are over 50 species of endemic freshwater fishes, including this one. It is a very poorly documented and understood ecosystem that remains critically threatened. Ricefishes as a group, and in particular this stunning new species, are fantastic icons to generate interest in and encourage conservation of the endemic freshwater biota of Sulawesi.

Come by the Academy and check them out!

Filed under: Fish — rainforest @ 12:01 am

March 9, 2011

New Addition

Photo by: Rachael Tom

Of all the cichlids living inside the Flooded Forest, the Apistogramma eunotus is the smallest. These dwarf cichlids are one of the newest additions to this display. In order to increase their chance of survival in a tank full of predators, the Amazon Flooded Forest team released a large number of Apisto juveniles into the tank hoping that they would immediately seak cover.

Photo by: Rachael Tom

The fish remained in hiding for several months while they grew and adapted to their new surroundings. These juveniles were bred in-house and when they numbered in the hundreds, it was time to experiment. Now, fully grown at around 3 inches, the feisty Apistos have secured territories in the nooks & crannies of the tank and have started to breed.

Photo by: Rachael Tom

If you look closely around the complexities surrounding the tunnel, you may see a bright yellow female in brooding coloration leading her fry to forage. Even though she may only be an inch, she shows all the characteristics of being cichlid – she will defend her fry against the much larger inhabitants of the tank.

Photo by: Rachael Tom

Filed under: Fish — rainforest @ 4:02 am

February 12, 2011

Love is in the air (literally!) and on the rocks, and in the water….

So, for all the single ladies who:
• don’t like being inconvenienced by trite ‘pillow talk’ – take a page out of our  Ghost Mantid’s (Phyllocrania paradoxa) book and consume your partner post-amour.

mantid mating

Female mantids often eat males after copulation.

• are interested in guys from South America who can co-parent might want to meet our Turquoise Tanager (Tangara mexicana).


Photo by Rachael Tom

Male tanagers help feed chicks and protect the nesting site.

• feel it’s always good to have a ‘spare’ might be interested in our Machete Savane snake (Chironius carinatus).

Photo by Brian Freiermuth

Photo by Brian Freiermuth

Snakes and lizards have a bi-lobed reproductive organ called the hemipene.

• don’t trust a guy with a wandering eye should avoid entanglements with our Panther chameleon (Furcifer pardalis).


Photo by Rachael Tom

Chameleon eyes are mounted on turrets that can move independently of each other.

are suckers for sweet talk and don’t mind carrying extra baggage should visit our  Slipper orchid (Paphiopedilum transvaal).

BO02 Paphiopedilum transvaal

Photo by Rachael Tom

The slipper-shaped pouch traps insects so they are forced to climb out collecting and depositing pollen that fertilizes the flower.

try not to get involved with guys that just can’t let go should keep their distance from our Red-eyed tree frog (Agalychnis callidryas).

Photo by Brian Freiermuth

Amplexus is a form of pseudocopulation in which the male amphibian grasps the female with his front legs while fertilizing her eggs.

• prefer regurgitated fruit over a dozen roses might want to give our Blue and Gold macaw (Ara araruna) another look.


Photo by Rachael Tom

Parrots exchange food via regurgitation as part of a courtship ritual before breeding.

Filed under: Birds,Butterflies,Fish,Herpetiles,Insects & Arachnids,Plants — Vikki McCloskey @ 1:52 pm

January 12, 2011

Cardinal Tetras at the Academy

One of my favorite tanks that I care for is the Academy’s cardinal tetra display. It is across from the freshwater stingray collection in the Amazon Gallery of our rainforest and looks like this:

Photo by: Brooke Weinstein

Cardinal tetras have the scientific name Paracheirodon axelrodi and are native to the upper Orinoco and Negro Rivers of the Amazon. They are a small, peaceful fish that likes to live in large groups, or shoals.

Many people confuse cardinal tetras with their more notorious counter-part, the neon tetra. However, they are two separate species with one very easily observed difference. In the cardinal tetra the red stripe on the lower half of the body extends the full length of the fish from the eye area to the tail. In the neon tetra the red stripe only begins at mid-body, roughly below the dorsal fin, and extends to the tail.

Here is a close-up of some of our cardinals so you can appreciate how colorful they are:

Photo by: Ron DeCloux

You might think that this fish’s bright, metallic stripes would make it rather obvious to predators. In fact, however, the opposite is true because their colors actually change in response to different lighting and background conditions. Here in our colorless and clear aquarium water their coloration appears shockingly bright. But when viewed through the very dark tannin-stained water they inhabit in the wild, their coloration actually appears quite dark. Furthermore, their metallic stripes reflect light only at a specific angle. When the fish are near the surface, this reflects a bright mirror image onto the underside of the water surface and provides a false target for predators.

In the wild cardinal tetras consume a variety of foods including insects, detritus, eggs, algae, fungus, fruit and fish larvae. Here at the Academy we also offer our cardinals a variety of foods including flake food, brine shrimp, baby brine shrimp, bloodworms, glassworms, and algae wafers.

Our cardinals love to hang out amid the live plants in their exhibit and share their home with a handful of other Amazonian fishes like:

The Amazon puffer Colomesus asellus:

Photo by: Ron DeCloux

The golden pencilfish Nannostomus beckfordi:

Photo by: Ron Decloux

The orange-neon corydoras:

Photo by: Ron Decloux

And the dwarf sucker-mouth catfish Otocinclus affinis:

Photo by: Ron Decloux

Millions of cardinals are caught from the wild and exported from Brazil every year. Despite this, the fishery is widely considered to be one that is managed very well. The fish are not allowed to be caught during the breeding season or shortly thereafter, and the Amazon/Rio Negro area is so vast that fishermen do not go back to the same site for years, thus allowing the cardinals to replenish. Project Piaba is a fantastic organization which works to help educate collectors/exporters and improve the conditions under which the fish from Brazil are caught, conditioned and shipped to the world. Their rallying cry is, “buy a fish, save a tree!” The assertion behind the slogan is that people with a stable economic livelihood from the fishery don’t engage in more ecologically destructive activities, like deforesting. Learn more about it at www.projectpiaba.org.

The next time you visit us be sure to check out this exhibit! Hopefully you’ll love it as much as I do…

Filed under: Fish — brooke @ 4:26 pm

December 9, 2010

Third Ones a Charmer

With the recent addition of our third arapaima (Arapaima gigas) to the flooded forest, now is the opportune moment to give more information on how we manage these fish. The two large arapaima are fed twice weekly with frozen trout, herring and capelin. These frozen fish are supplemented with a multi-vitamin to account for any lost nutrients during the thawing process. However, the newest addition, which is about three feet long, is fed daily – both to encourage growth and to discourage predation on the smaller fish in the tank.

Here is a picture of our newest addition surrounded by pacu:

Photo by: Allan Jan

The daily feedings have the effect of associating people with food – in essence, it begs for food whenever a biologist is around the rim of the tank. This allows us to monitor the fish’s health and behavior easily; and in a 100,000 gallon tank, a three foot long fish can be hard to spot.

One very hungry little arapaima:

Photo by: Allan Jan

For more general information on Arapaima gigas, check out our Rainforest FAQ’s post.

Photo by: Allan Jan

Filed under: Fish — rainforest @ 11:41 am

November 24, 2010

Happy Thanksgiving from your Rainforest Biologists!

Tis the season to celebrate a bountiful harvest. The rainforest biologists would like to give thanks that we are able to offer a wide variety of high quality food for the animals in our charge. This exhibit contains many different taxa that require many different food items. Here is a sample menu of what some of our rainforest inhabitants will be having for their Thanksgiving weekend….

Their diet consists of fruit, nuts, seeds, pellet, and vegetables.

parrot treats

Photo by: Rachael Tom

bowls of produce

Photo by: Rachael Tom

Neotropical Passerines
Their diet consists of fruit, seeds, vegetables, pellet, and protein items.

passerine diet

Photo by: Rachael Tom

We use several feeder insect species, including the larvae stage of mealworms Tenebrio molitor, waxworms Galleria mellonella, and soldier fly Hermetia illucens
feeder insects

Photo by: Rachael Tom

Carnivorous, herbivorous, or omnivorous; reptile diets are as diverse as the reptiles themselves. Some reptiles even eat other reptiles!

iguana diet

Photo by: Rachael Tom

Below are some of the feeder rodents we utilize. We order these frozen from a company that raises them specifically for food and humanely euthanizes them. They are then thawed out over a 24 hour period and then warmed so that the heat-sensing reptiles find them deliciously attractive.
feeder rodents

Photo by: Rachael Tom

Not as diverse in their nutritional requirements as reptiles, most of our amphibians enjoy insects.

Below is the ubiquitous cricket Acheta domesticus, probably the most popular feeder insect. We feed out various stages, from newly hatched (called pinhead) to adults, like below.

Photo by: Rachael Tom

Most butterflies are nectar eaters, though the owls and blue morphos like over ripe fruit as well. Here is a Heliconicus ismenius drinking nectar from one of the many nectar-producing plants in the rainforest. We also provide artificial nectar daily along with ripe fruit.

Heliconius ismenius_Rachael Tom

Photo by: Rachael Tom

Fish eat almost everything that is dropped into their tank!

pellet feed

Photo by: Rachael Tom

Some of the frozen fish we feed to our collection fish and other creatures at the Academy: capelin Mallotus villosus, herring Clupea spp, and trout Oncorhynchus mykiss.
herring, capelin, and trout, oh my

Photo by: Rachael Tom

It takes quite a bit of research and time to create diets that fulfill so many varied nutritional requirements for our hugely diverse live animal collection. Below you can see one of our paradise tanagers Tangara chilensis next to its diet. Enjoy your Thanksgiving everyone!
beautiful paradise

Photo by: Rachael Tom

Filed under: Birds,Butterflies,Fish,Herpetiles,Insects & Arachnids — rainforest1 @ 1:20 pm

November 8, 2010

Life Support System of the Flooded Forest

This posting will give you a glimpse into what it takes to successfully maintain the thriving community of animals that call the Academy’s 110,000 gallon Amazon Flooded Forest display home. Our tank, located at the bottom of the Academy’s rainforest dome, is teeming with hundreds of fishes–pacu, cichlids, leporinus, silver dollars, a giant river turtle, a tarpon, peacock bass and four species of catfish. Most significntly we also display three arapaima, one of the largest species of freshwater fish in the world, two of whom exceed 8 feet in length! 

Fish kept in an aquarium are confined to a very small quantity of water as compared to their natural habitats in the wild. In the wild, fish wastes are instantly diluted. But in an aquarium, waste products can quickly accumulate to toxic levels. These waste products include poop, scraps of uneaten food and plant material. The latter is an especially large factor for a tank sitting at the bottom of a rainforest! Skimmer baskets located in three different spots collect most of the leaves that fall into the water and are cleaned every week by aquarium Biologists.

Photo by: Brooke Weinstein

If left to accumulate this organic material would eventually decay, releasing ammonia. Even small amounts of ammonia are deadly for fish. Fortunately, the world is full of bacteria that want nothing more than to consume the ammonia and convert it into less toxic substances (nitrite then nitrate). All the bacteria require to perform this beneficial function is a surface to attach to and oxygen rich water. For our display we filter our water through three large sand filters (see photo below).

Photo by: Brooke Weinstein

The sand removes any fine particulate matter and provides lots of surface area for bacteria to colonize. Remember that nitrate is only less toxic than ammonia, not non-toxic. Over time the nitrates would accumulate until they, too, became toxic. Also, because nitrate is a fertilizer, high nitrate levels can lead to excess algae growth. Part of our routine maintenance is to “back-wash” our sand filters twice weekly. Our engineers flush 20,000 gallons of water backwards through the sand and into the Academy’s water recycling system. This physically removes any debris from the filters and, when the tank is refilled with fresh water, decreases our nitrate levels by 20% each time.

Like a living organism, the life of our Amazon display depends on its circulation, which is the flow of water through its filters and around the tank. In our system the movement of water through our filters exposes a constantly changing air/water surface interface through which the major exchange of gasses, primarily water and carbon dioxide, takes place. The pumps we use, shown below, are powerful enough to completely turn over the 110,000 gallons in our tank once every hour!

Photo by: Brooke Weinstein

For all the inhabitants of the Flooded Forest here at the Academy it is, fundamentally, the invisible water conditions that make their display a home away from home!

Filed under: Fish — brooke @ 2:57 pm

July 29, 2010

Tambaqui: Flagship Fish of the Amazon

Look at our 110,000 gallon Amazon Flooded Forest display and one of the first fish you are likely to notice are the tambaqui–we have about fifty of ‘em! They are commonly, yet erroneously, called pacu in English and are in the same family as the infamous piranha. Tambaqui can reach over 3 feet in length, over 60 pounds in weight and are widely distributed throughout the Amazon and Orinoco basins.

Photo by: Ronald DeCloux

These fish display distinct countershading; they’re black ventrally and yellow to olive-green dorsally. However, the most characteristic feature of these gentle giants is the amazing dentition they have evolved. Their teeth are cuspid, resemble human molars and, along with their powerful jaws, allow them to crush the fruit, nuts and seeds on which they heavily feed.

Look head-on at one of our tambaqui and you’ll notice that it appears to have two protrusions on the upper part of its snout kind of like the headlights on a sports car. These are actually nasal flaps that raise, allowing more water to flow past the olfactory cells of the nose and helping the fish locate fruit that has fallen into the water from overlying trees.

Here at the Academy we feed our tambaqui daily “fiestas” consisting of assorted fruits and a small amount of greenery. Organic only, of course! The photograph below depicts an average daily meal consisting of apples, pears, bananas, figs, honeydew, cantaloupe and grapes:

pacu fiesta

Photo by: Brooke Weinstein

They are voracious feeders!

Photo by: Brooke Weinstein

In the wild, tambaqui are key seed dispersal agents and are critical to the regeneration biology of Amazonian floodplain forests. They are also prized for their uniquely mild, sweet flavor and are one of the most heavily exploited food species in the Amazon. Considerable economic importance for commercial fishing and for breeding in captivity (aquaculture) has placed a lot of attention on this species; it is exemplary of a tropical rainforest resource that can be managed in the wild.

Filed under: Fish — brooke @ 3:30 pm

May 27, 2010

Making Babies


Photo by: Allan Jan

Cichlids are some of the most charismatic and beautiful freshwater fish, with well over 1,000 species spread over 5 continents. One aspect that makes cichlids so special is the evolution of parental care. The severums in the Flooded Forest have been busy recently – pairing up, guarding territory, and cleaning that territory. All this preparation eventually leads to spawning activity and then possibly hundreds of fry. Look carefully in the tank and you may see severum pairs foraging with their fry. The parents have their work cut out for them, living in a tank surrounded with predators. Many fry will be eaten, but the survivors are a testament to the aggression cichlid parents display.

baby severum

Photo by: Allan Jan

Filed under: Fish — rainforest @ 1:47 pm

April 6, 2010

Wild Bettas of Borneo

wild betta taeniata SE Asia Borneo CAS rainforest

Photo by: Charles Delbeek

The majority of visitors looking at our SE Asian Stream exhibit on the Borneo level of the rainforest miss one of my favorite fish here at the Academy, a species of wild betta (pronounced BET-TUH not BAY-TUH) that is probably Betta taeniata.

When people think about bettas what they are probably picturing is the ubiquitous Betta splendens, also known as the “Siamese Fighting Fish”. This fish is perhaps the most popular fish kept in the aquarium hobby and a trip to most any pet store will usually find dozens, if not hundreds, of these fish kept in very small bowls or plastic cups. These unlucky animals are uniquely able to survive in substandard conditions like this because they possess what is called a labyrinth organ. It allows them to breathe oxygen straight from the air at the surface of the water. This is an adaptation that has evolved to help them thrive in water that is so hot it holds too little oxygen, or is too polluted, for most fishes.

Because Betta splendens is frequently referred to simply as “betta”, many fish fanciers are unaware that there are actually about 65 different species in the Betta genus. Many of these are Threatened, Endangered or even Critically Endangered in the wild so keeping and breeding them in captivity is of paramount importance!

All bettas show strong sexual dimorphism, meaning that males and females look very different from each other. Below are photos first of a male and then of a female individual currently on display in our rainforest.

wild betta taeniata SE Asia Borneo CAS rainforest

Photo by: Charles Delbeek

wild betta taeniata SE Asia Borneo CAS rainforest

Photo by: Charles Delbeek

If you’re as smitten as I am with these fascinating beauties look for another species of wild betta, Betta albimarginata, on exhibit in the Staff Pick section of the aquarium!

Filed under: Fish — brooke @ 11:51 am
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