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Golden Gate Park
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Please note: The Academy will be closing at 3:00 pm on 10/24 (final entry at 2:00 pm). We apologize for any inconvenience.

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Rainforests of the World 

January 25, 2011

Rainforest Refresher!

The rainforest exhibit reopened last Monday after being closed for two weeks for maintanence. Although guests could not enter the dome, they could look through the glass at any time during the day and see staff and volunteers hard at work doing a various range projects that can’t normally get done when the rainforest is open to guests.

During the first morning of the closure, supplies were immediately brought in so the biologists could get right to work. Everyone had big plans for their respective sections. In the picture below, you can see the abundance of plants waiting to be secured in their new home.


Photo by: Kevin Manalili

more plants!

Photo by: Kevin Manalili

The plant collection grew signficantly. Biologists added plants to the ground level, as well as to the trees and walls. They also created a whole new living wall on the Costa Rica level! This process takes a lot of time because the horticulturists had to secure moss on the wall before adding each individual plant. It looks great!

CR wall 1

Photo by: Kevin Manalili

CR wall

Photo by: Kevin Manalili

In order to keep the smaller plants safe on the ground, the horticulturists made paths so that the other biologists wouldn’t accidentally step on anything. The paths look very natural and makes it much easier to get around.


Photo by: Sarab Stewart

Herpetologists also added plants to their terrariums as they cleaned and rearranged exhibits. Almost every exhibit looks a little different with the new plants, substrate and even some new animals! Here is a picture of a volunteer cleaning out one of the Costa Rica exhibits:


Photo by: Kevin Manalili

The biologists were not the only ones working hard. Electricians, engineers and contractors came to help on different projects. One of the more difficult activities was replacing the old and cracked glass panes that make up the outside of the dome. Everyone had to work together to make sure no butterflies or curious birds escaped. You can see the netting that was put over the top of the hole just in case one of the free flying critters did manage to sneak through.

more glass

Photo by: Kevin Manalili

glass pane

Photo by: Kevin Manalili

The closure was an all around success. It allowed everyone to complete some lingering projects that needed to get done in order to keep the rainforest healthy.

You just got a small taste of what you can expect when you visit. Come check out the difference and see what you think in person!!

Filed under: Uncategorized — rainforest @ 12:35 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

January 7, 2011

The Wondrous World of Glass Frogs

This summer, while in Costa Rica, Steinhart aquarium biologists were privileged to encounter a variety of glass frogs, Family Centrolinidae. These frogs are appropriately called glass frogs because of the see-through nature of their skin. Although glass frogs have some pigment in their skin, mostly green, it is possible to see through their bellies and observe their organs.

Hyalinobatrachium colymbiphyllum

Photo copyright of: Brian Freiermuth

Above: Hyalinobatrachium colymbiphyllum

Glass frogs breed and lay their eggs on leaves overhanging water, usually streams. Eggs may be predated on by insects and so the male sticks around to protect the eggs.

Cocharanella granulosa

Photo copyright of: Brian Freiermuth

Above: Cochranella granulosa eggs develop on a leaf over a stream at the Costa Rica Amphibian Research Center, located on Costa Rica’s Carribean slope.

Hyalinobatrachium valerioi

Photo copyright of: Brian Freiermuth

Above: Hyalinobatrachium valerioi male gaurds eggs on a leaf above a stream on Costa Rica’s Pacific slope.

Snakes also may eat the eggs. We observed this snake, Dipsas longiferis eating the eggs of a granular glass frog, Cochranella granulosa. It is unlikely that the attending male could do anything to protect his eggs in this case. We did not observe him nearby.

Dipsas longiferis

Photo copyright of: Brian Freiermuth

Above: Dipsas longiferis was seen eating a glass frog egg mass above a rainforest stream.

When the eggs hatch they fall into the stream below. The tadpoles lack pigment and as a result are red in coloration. While many tadpoles are dark in color and active in the water column or on the bottom of ponds or streams, glass frog tadpoles seem to be adapted well to life under rocks and other cover in streams.

Cochranella granulosa

Photo copyright of: Brian Freiermuth

Above: Cochranella granulosa tadpole. Note the reduced eyes, long , strong swimming tail and lack of pigment.

Just before the tadpoles metamorphose into tiny little frogs their eyes begin to enlarge, their hind legs grow in and their digestive tracks change from one well suited to eating vegetation to one that will exclusively feed on animal prey.

Cochranella granulosa

Photo copyright of: Brian Freiermuth

Above: Cochranella granulosa tadpole has developed legs, large eyes and the vertebrae are much thicker than those of earlier stage tadpole.

Concharanella granulosa

Photo copyright of: Brian Freiermuth

Above: Cochranella granulosa tadpoles at different stages of development. Note the one on the left has started to develop the typical characters of a frog, though the mouthparts are still distinctly tadpole. The one on the right is much less developed with its spiral shaped gut being its most obvious characteristic.

Cochranella granulosa

Photo copyright of: Brian Freiermuth

Above: This Cochranella granulosa has its front legs and is now a terrestrial animal, despite having not yet absorbed its strong swimming tail.

Cochranella granulosa

Photo copyright of: Brian Freiermuth


Above: This Cochranella granulosa has nearly absorbed all of its tail. Within the next several days it will start feeding on bugs—an entirely different diet than it has ever had before.

During our trip we saw several species of glass frog. We were fortunate to bring back two species for exhibit. Currently, we are growing out tadpoles which will be the founders of a captive population that will supply our exhibits in the years to come.

Teratohyla spinosa

Photo copyright of: Brian Freiermuth

Above: Teratohyla spinosa on the Carribean slope of Costa Rica.

Filed under: Herpetiles — rainforest @ 7:50 am

January 2, 2011

Species profile: bananaquits!

Please Note: The rainforest exhibit will be closed 3 January through 14 January, reopening Saturday, 15 January at 9:30am. This closure allows us much needed time to make repairs and additions to keep this exhibit looking great. We apologize for any inconvenience.

tweeties 004

Photo by Rachael Tom

Upon entering the Rainforest Exhibit here at the Academy, one’s senses are immediately perked up by the sights, sounds, and feel of this habitat. The high humidity, dappled sunlight, flowering plants, whimsical butterflies, and chirping birds are all part of the experience. If you’re one of the many lucky ones, you will have an encounter with one of my favorite species: the bananaquit Coereba flaveola.


Photo by Rachael Tom

These brave, boisterous little birds provide some lively entertainment as they make rounds in their territory, searching for food or something interesting to poke at. Bananaquits are tiny….usually around 12 grams. We are lucky to house two pairs in our rainforest. Pink and Blue (named after their color bands) have made the eastern 4/5ths of the rainforest their territory, leaving just a tiny fraction on the west side for Purple and Red. We acquired our bananaquits about a year ago from the San Diego Zoo, where they were hatched. They have adapted extremely well to our exhibit and are one of the most frequently observed birds.


Photo by Rachael Tom

Bananaquits have an extensive range: nearly all Caribbean islands (except Cuba) along with most of Central America and tropical South America. They tend to stay in lower elevations and avoid expansive forest or desert habitat. Bananaquits have adapted to more open, disturbed, or secondary growth habitat, so they do very well around human habitation. In fact, at many of the Caribbean island resorts, tourists often have close encounters with these curious birds.
Due to their wide distribution over the diverse cultures of the Caribbean and mainland Latin America, these birds have many common names. Some of the more colorful ones are Beeny Bird (Jamaica), See-See Bird (Grenada), and Sucrier (Haiti). Another common name is sugar bird, as bananaquits are sugar feens. Their primary diet is nectar, so a sweet tooth they do have. These birds are also fond of fruit and insects. In fact, our bananaquits are an important predator of some of the plant-damaging insects that inhabit this exhibit.


Photo by Rachael Tom

The taxonomy of bananaquits has been debated for some time now; they have many subspecies over their vast range. They typically lay two, sometimes up to four eggs that hatch after a 12-14 day incubation period.


Photo by Rachael Tom

So stop by when the rainforest re-opens and keep an eye open for these lively little birds!
tweeties 005

Photo by Rachael Tom

Filed under: Birds — rainforest1 @ 4:34 pm

December 24, 2010

Identifying Birds and Their Nests!

This is our male blue-grey tanager (Thraupis episcopus). Although there is no obvious sexual dimorphism (physical differences between males and females) within this species, we know who is who because our male and female are banded differently.
Our male is wears a blue band on his right leg with the number 14:

Photo by: Rachael Tom

His mate wears a silver band on her right leg with the number 99 and a white band on her left leg. All of the birds in our Rainforest Exhibit have leg band color combinations unique to their species and in some cases, do not wear a band at all if they are the only individual of their species, or, the only sex of their species and sexual dimorphism exists. This allows our biologists to easily identify individuals and tell males apart from females.

We have several different sizes of leg bands because some of our birds have bigger legs than others. Here is a picture of one of our smaller bands:

Photo by: Rachael Tom

Our birds wear their bands much like a person wears a bracelet or an anklet- the bands are narrow enough so they don’t slip off, but wide enough so our birds feel comfortable . Banding a bird is just a matter of slipping the band on. This is a picture of two biologists banding a juvenile silver-beaked tanager (Ramphocelus carbo):

Photo by: Rachael Tom

Photo by: Angelo Rufino

Although we have multiple bananaquits (Coereba flaveola) on exhibit, we know that this is the more dominant female with a history of successful reproduction because she has a pink band on her left leg:

Photo by: Rachael Tom

Two female red-legged honeycreepers (Cyanerpes cyaneus) can be confusing, but we know which female is which because one is banded pink on her left leg, while the other is banded orange on her left leg:

Photo by: Rachael Tom

Again, not all of our birds are banded. Our male and female red-shouldered tanagers (Tachyphonus phoenicius) are the only pair of their species on exhibit, and look very different from each other. Female red-shouldered tanagers are dark grey with a light grey “mustache” and belly, while this is what the male looks like:

Photo by: Rachael Tom

With these bands, we can easily see what each bird is up to every day and document their health and behavior:

Photo by: Rachael Tom

Because there are a lot of other Academy staff that work in the Rainforest Exhibit, we also have a method of identifying bird nesting sites that need to be carefully worked around. By gluing pictures of our birds onto small magnets…

Photo by: Rachael Tom

we are able to place the magnets onto a map of the Rainforest for all staff to see. This way, everyone knows which birds are nesting where. When this picture was taken, a pair of bananaquits and opal-rumped tanagers (Tangara velia) were nesting in the peach palm:

Photo by: Rachael Tom

By banding birds and keeping track of bird nesting sites, biologists are able to better identify each individual bird, their health and their behaviors. Without bird bands and a bird nesting map, how would you be able to tell which individuals within a species were responsible for the nest below?

Photo by: Rachael Tom

Filed under: Birds — rainforest @ 11:45 am

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 29, 2010

Farming ants and flying snakes, oh my!

Here at the California Academy of Sciences, we are lucky to be able to work with some pretty fascinating species. Recently there were two interesting news articles about some of these species.

Photo by: Rachael Tom

The first article looks at how leaf-cutter ants coevolved with the fungus that they farm, and it turns out they utilize a bacteria as a pesticide to keep their crop intact. The researcher says leaf-cutter ants have been farming for 50 million years! Looks like they got just a little head-start on humans. Read the article HERE.

Photo by: Rachael Tom

The other article looks at the snakes of Southeast Asia that have evolved the ability to glide in the canopy. One of the species they looked at is the paradise flying snake Chrysopelea paradisi , which you can find right here in the Borneo level in the rainforest at the Academy (see photo above). They have some pretty neat video. Read the article HERE.

Here’s a video of some of their research. I thought it was interesting how much of the snake hangs off the branch before it launches itself into the air.

Filed under: Herpetiles,Insects & Arachnids — rainforest1 @ 3:50 pm

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 17, 2010

Our Pipa pipa are breeding!

You may be wondering what a Pipa pipa is. Well, they are a very interesting amphibian species, Pipa pipa, that goes by the common name Suriname toad. They are an aquatic species native to northern South America with cryptic camouflage. If you look at them, they have little projections around their head and body that make them look a little like leaves. This helps them blend in very well. Even better is some of those little projections are sensitive to movements, which helps them recognize prey that swims too close.

Pipa pipa amplexus

Photo by: Brian Freiermuth

While those characteristics are cool, it is the Suriname toad’s reproductive biology that makes it truly remarkable. After a period of amplexus (as seen in the photo above), the female lays her eggs and the male fertilizes them. But what is different is that the eggs are not laid on a leaf or attached to a stick or under a rock like most frogs. Nope, this is one unconventional frog. Check this out:

eggs in back!

Photo by: Brian Freiermuth

Suriname toad females incubate their eggs in their own backs. That’s right, I said in their own backs!!! With the help of the male and some fancy acrobatics, the eggs are placed on the back of the female. Then they begin to embed into her back and are eventually mostly or entirely covered by a thin layer of skin. If that wasn’t crazy enough, the tadpoles never hatch from the eggs. Instead, they undergo complete development inside the back of the female. When they finally emerge they are little, nearly identical versions of the adult!

Pipa pipa

Photo by: Brian Freiermuth

Thinking to yourself, “Holy flipping frogs, Batman, I would love to see that!”? Well, now is your chance. On November 13th, we observed that one of our females has eggs on her back. Currently, our other female has been in amplexus with a male so it is very likely that she will lay eggs soon. It is expected that the eggs or at least the general position of them will be noticeable for several weeks. So if you want to see one of the neatest things in the natural world, come on in and check them out! They are on exhibit on the Amazon level near the anaconda exhibit.

Filed under: Herpetiles — rainforest1 @ 1:18 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
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Academy biologists share the inside scoop on the Academy's 'Rainforest of the World' exhibit.

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