Identification and Husbandry of
Amazon Basin Emerald Tree Boas
It is a rare individual, snake lover or not, who isn't caught short of breath at the sight of a mature
emerald tree boa coiled around a tropical limb. But few snakes are as misunderstood by reptile
keepers and breeders alike. The common myth is that they are difficult to keep, of vile
temperament, and next-to-impossible to successfully breed in captivity. These theories are quickly
dispelled once a few basic husbandry conditions are understood and met.
What is an Amazon Basin Emerald?
There are two main types of Corallus canina: the Surinam (or Guyana Shield) and the Amazon
Basin. The former is found exclusively in Northern South America and is separated geographically
from the latter by a range of mountains. The aptly-nicknamed "Amazon Basin" emerald is found
along much of the Amazon river basin, from southern Surinam, Southern Guyana, Southern
Venezuela, to Colombia, Peru and Brazil into the surrounding lowland jungle of the expansive
river. The two are as different from each other as night and day; and someday will likely be
identified as distinct subspecies. The differences in morphology, scalation, coloration and
temperament are striking. The species was discovered in 1754 by Linnaeus (Mus. ad. Frid. p. 39,
pl. iii); although to this day few subspecific differences have been noted in scientific literature.
Briefly, these are the most obvious differences. The Surinam snake (which is the same as the
Guyanan, or Venezuelan, or French Surinam - for their range overlaps across all of these
countries) is generally more of a tall configured snake, with less tendency to develop the squarish
body profile of the Amazon emerald.
The coloration of the Surinam is generally more lime green; whereas the Amazon tends to become
more deep emerald green as it matures. Some specimens become so dark that they almost appear
black, and a dark green Amazon is truly stunning, further enhanced by it's bright yellow and white
markings. Why the Amazon is darker remains a mystery, but these are the great questions we are
doomed to debate and hypothesize - not unlike the paleontologists wrestling over the dinosaurs'
behavior from scant fossil evidence. The differences in coloration are probably anybody's guess,
for generally nature endows animals from cooler regions with darker body colors (assumedly to
absorb more solar radiation). In this case, popular theory would seem to be contradicted.
The white pattern on the Amazon is far whiter, and the yellow is usually more brilliant than the
Suriman emerald. Where the Amazon's dorsal markings are normally connected (striped) and pure
white, the Surinam's are more likely to be broken; and the white is laced with gray/blue hues.
Interestingly, many Surinams possess a "sawtooth" white pattern which can be quite impressive.
The yellow tends to be paler on the Surinam, whereas the Amazon is usually graced with vibrant
yellow on the underside and labials, making the snake considerably more contrasty in appearance.
Scalation is somewhat different on the body, with varying counts, but the most noticeable
difference, evident to even the untrained eye, is on the dorsal surface of the head. The Surinam is
characterized with large plates, whereas the Amazon's head (specifically the snout region) is
covered with small scales. Other notable differences are evident on the rostals and labials.
I'm currently in the process of having skeletons of both types cleaned, and anxiously await
discovery of the possible differences in skull structure which seem to exist from viewing live
specimens. Unfortunately, an emerald's skull is made up of muscle and tendon-joined bits and
pieces, and it's difficult to recognize structural patterns where there is, in effect, little actual skull
structure to work with. Initial differences in the lower mandible joint (it's a two piece jawbone) and
actual jaw shape are noticeable to even my untrained eyes.
The last, and most enjoyable difference between the two snakes is that of temperament. The
Surinam is somewhat irritable, especially when freshly imported, while the Amazon is typically
tame and docile even when freshly captured. Once again, the reasons are anybody's guess.
Captive-raised Surinams sometimes become tame as they mature, but more often than not they
retain their rather infamous disposition, regardless of how much a loving keeper tries to alter their
basic nature. Most of the emerald tree boa bites I have incurred over the years (which are not
without considerable pain...) have come from encounters with Surinams. I have been keeping
emeralds off and on since the early 1970's (when they could be bought for as little as $25.00!!!)
and can count the bites from Amazons on one mildly scarred hand.
The Most Common Husbandry Problem
In a word: Regurgitation. The causes range from Crypto to environmental stress, but more often
than not, if the animal is properly maintained, the problem will never rear its ugly head. Frequently
an animal which has been maintained in one collection for years without a problem develops health
complications with a subsequent keeper. Following these basic rules will usually assure a
worry-free experience with emeralds.
Keeping Emeralds in Captivity
Regardless of which emerald you keep, the rules are basically the same. They are simple and rarely
can they be violated without dire consequences - hence the ill-gotten reputation referred to earlier.
Stick to the rules, and you'll have years of pleasurable experiences with your emeralds. Stray, and
your snakes will almost undoubtedly pay the price.
I have recognized six basic rules to successfully maintain emeralds. While some keepers report
varying degrees of success with slight variations in these basic concepts, few, if any succeed
without following these Six Commandments religiously. Someone ought to scribe them in stone.
Briefly, they are: (1) Don't keep them too warm (2) Maintain proper humidity cycles (3) Don't
feed them too often (4) Feed proper sized meals (5) Allow for regular defecations (6) Exercise
your snakes. These are all common-sense rules which apply to most captive herps in varying
degrees. In the case of emeralds, the parameters are more strict but easily attainable.
Rule 1 Watch the Temperature!
Somehow keepers tend to think of South America as hot and muggy all the time, and for the most
part they're right. Almost two decades ago I made my first trip to South America to see what it was
really like, and have since made many repeat expeditions to the land that, if I wasn't so established
here in the States, I would gladly call my home.
Emeralds are entirely arboreal, living from just above the forest floor to high in the canopy. The
mistaken assumption has often been made that they feed primarily upon birds - because of their
huge canine teeth and the basic arboreal nature of the beast. What has rarely been mentioned is
that the rodents of the region are just as arboreal as emeralds, and it's common to see varying-sized
rats in the treetops right next to the snakes.
Arboreal snakes are subject to more extremes in temperature and humidity than are terrestrial
reptiles. The reason is clear: ground temperature is more constant, whereas air temperature varies
both quicker and more dramatically.
I have recorded temperatures in the high 50's to the high 90's in the Amazon basin. I have also
climbed to the top of the canopy and felt just how much cooler it can be high off the ground, with
a gentle breeze flowing across one's sweaty brow. Consequently, an exothermic animal like an
emerald lives in a less stable environment than say, a redtail, or a rainbow boa. While the latter can
bask, raise its temperature to a suitable level, and retreat to a hollow log or leaf litter pile to retain
its body heat, the emerald tree boa cannot. It is primarily at the mercy of the air temperature. Since
reptiles are cold blooded and can't sweat off excessive body temperature (unlike tree-climbing
herpers...) the air temperature is a determining factor to these snakes.
You've been told temperatures reach the high 90's in the emerald's habitat, so a similar temperature
would be all right for a captive specimen, right? Not exactly. The temperature at the forest floor
can get downright unbearable, especially in light of the high humidity which typically cycles from
high, to higher, to amazingly high each day along the Amazon. But what is hot, or what feels hot to
us mammals, isn't necessarily felt the same way by reptiles. What I learned during my many forays
into the treetops is that it isn't nearly so unbearable up there. It doesn't feel that humid either, a
function of the almost constant breeze. But what the snake feels is another matter altogether.
It is fairly evident that emeralds are able to avoid excessive heat by remaining in the shade during
the middle part of the day. And the temperature in the shade is far lower than in the sun, as we all
know. At night, when the ground retains a considerable portion of it's daytime heat, and when
crepuscular herps are active and warm, emeralds typically cool off even more. By the time the cold
snake's body begins to warm up in the morning and into the afternoon, it probably only reaches
temperatures near the ambient air, but not equal to it. The cycle repeats itself at sunset and the
emerald tree boa lives as it always has, in an environment cooler than one might think.
It was after many trips to South America and more than a few unfortunate experiences with
captive emeralds that this lower temperature regime became apparent to me. As mentioned, the
most common emerald malady is the regurgitation syndrome. While everything in this article can,
and does, relate to eliminating the problem, temperature is one of the more critical factors in
avoiding emerald regurgitations.
The optimum temperature range for emeralds spans from night time lows (NTL) of approximately
75 degrees to daytime highs (DTH) of 82 degrees Fahrenheit. During the breeding season it is safe
to drop temperatures into the low sixties, and interestingly many of my adult females and subadult
animals continue to feed during these lower NTL's with virtually no difficulty in digestion or health.
Conversely, higher temperatures, such as 88-92, which some emerald keepers report as within
normal parameters, frequently result in regurgitations. One would suspect that emeralds have
relatively slow metabolisms and that at higher temperatures food items tend to putrefy and decay at
a rate which exceeds the animals' natural digestion capability. Hence, excessive gasses are
produced and the snake expels the food item. I have frequently taken an animal with a history of
regurgitation (which have usually been tested first for crypto, etc.) and turned it around by keeping
it at slightly lower temperatures. The process of recovery may take more than a year, but patience
is a must to successfully help the animal re-establish healthy gastrointestinal functions.
A successful temperature cycle would be to have a cage or room reach a NTL of 75. Spraying
cages, turning on lights, and raising the temperature setting should bring about a DTH of around
82-84 by late afternoon, at which time the lights should go off. Emeralds live in an almost perfect
12/12 day/night photoperiod throughout the year - so 6 a.m. to 6 p.m. is an ideal day-night cycle.
The cage should begin to cool when the lights go off, and the humidity should also begin to drop,
creating (simulating) a cooler and less humid night period. Anywhere from 65% R.H. at night is
good, while 80% R.H. or more during the day is adequate. Some of my cages, made by Vision
Herpetological, oftentimes reach humidity levels near 100% by late afternoon. Quality waterproof
cages are a must when striving to reach these high humidity levels. Adequate humidity oftentimes
rots wooden cages, no matter how much sealant you use.
Stick to these parameters and the matter of health and regurgitation will be minimized, when
managed in conjunction with the additional maintenance rules.
Rule 2 Maintain Adequate Humidity and Airflow
We touched on humidity in relation to temperature, since they are related. The higher the
temperature, the more humidity the air is capable of holding. When air cools, the less likely it is to
hold high levels of moisture. The point at which water comes out of the air is called the dewpoint,
but since we're not trying to make it rain by controlling the dewpoint, it's senseless to attempt to
get moisture from the air by manipulating moisture levels in relation to temperature. Just remember
that it's natural for warmer air to hold more humidity.
Except for the breeding season, at which time my emerald cages get misted sometimes for hours
on end, and at a time when the Amazon river literally floods from months of rain, emeralds do well
if subjected to daily humidity cycles of hot, humid days and cool, less humid nights. Notice I did
not say dry nights, for it is never dry where emeralds come from. Nature took millions of years to
evolve this animal to successfully flourish in a humid environment, and changing conditions to dry
is an invitation for stress-related respiratory disorders and general discomfort for the snake.
There are different kinds to humidity. The worst is stagnant, and the best is moving,
naturally-produced humidity. Simply spraying an animal and its cage will work, but it is far better
to install a room-temperature, fresh water (minus chlorine, florine and chloramids) misting/rain
system for your emerald. I'm currently setting up a rain system in an emerald room which also has
a misting mode so I can go from heavy droplets to a gentle, foglike mist and provide the animals
varying degrees of humidity and water-related "weather" occurrences. Opening the windows during
a thunderstorm is a neat idea, too, with all the ionized air molecules stimulating the snakes, plants
and even their keeper into a highly-charged state. When it rains around this household a frantic
scene emerges. Our dog, who normally fears nothing, hides at the sound of lightning. Our outside
guard animals, pairs of swans and geese, begin celebrating by flapping and splashing all over the
place. And the reptile keeper (yours truly) runs from room to room, and even cage to cage,
opening doors and windows to let the storm in. The bigger the storm the more our animals, except
the dog, like it.
As mentioned earlier, spraying emeralds in the morning is best. With the increase in day
temperatures, the humidity will rise naturally as the day progresses (Remember: warmer air will
hold more humidity). With the discontinuation of lights and temperature at nightfall, the humidity
will naturally diminish and provide the animals with a less humid evening/nighttime period.
Humidity can be augmented in several ways. One method is to use a large water pan, to provide a
significant surface area for evaporation into the cage. Another is by using bedding that holds
moisture well, and which effectively increases the surface area to provide additional evaporation.
The last is to fill the cage with live plants, such as cage-hardy pothos or ficus. Plants represent a
source of transpiration and oxygen production to make the cage more natural feeling to the
animals. The result is a cage which smells, feels, and even looks very similar to the jungle from
which emeralds originate.
A critical factor is that of air movement. Stagnant air isn't good, for it can propagate fungal and
bacterial growth which could be detrimental to your snake's health. It is necessary to provide a
mechanism for the air to move, which also promotes fluctuations in day and night humidity levels.
This can be accomplished easily, providing your snake room isn't overly-humid to begin with. For
those living in dry climates like me (Colorado), that's not a problem. For those living in humid
climates like Houston, or Atlanta, or Miami, it is a little more of a job. The important factor is to
provide ventilation and airflow. In most cases, the more cage ventilation available, the less need
you'll have for airflow.
My cages have 1/4" screen mesh covering the entire top, along with vented sides, or screened
fronts with vented tops, to provide natural airflow. In addition, a ceiling fan operates to keep the air
in slow and gentle motion. Since the entire room is dedicated to emeralds, and all the cages are
humid, this ventilation does not dry the cages excessively. You must be the judge of your
cage/room design to determine whether it needs more-or-less ventilation OR more-or-less airflow.
Ventilation is accomplished by venting the cage. Airflow represents the movement of air around
and in the cages.
When I stick my head inside an emerald's cage, while watching out for a feeding reaction and a
possible painful bite (which is rare during daylight hours, since they're very sedentary during the
day) the cage must smell alive with plants and wet bedding, and it must be very humid. Otherwise
the snake most likely isn't comfortable. Watching an emerald's body language is very important.
Look for tight, orderly coils which represent a comfortable snake. Conversely, loose coils are the
first sign of discomfort.
Rule 3 Don't Feed Emeralds Too Often - Burmese Pythons they are NOT!
My favorite quip for emerald keepers, in regard to feeding, is that "They aren't Burmese pythons!"
I've raised Burms before and have seen them grow almost geometrically in relation to their food
intake. Likewise with corn snakes, tri colors, and even red tail boas. But NOT! when it comes to
emeralds. While the occasional emerald might take frequent meals successfully, most will
eventually become stressed and begin regurgitating if fed too often. Even captive-born and raised
babies, which oftentimes feed and grow like gangbusters, usually reach of point of "no mas" and
will regurg when their systems have had enough. Then you're in for problems, as consequent
meals will often come up and the keeper immediately thinks the snake is sick. Actually it is: sick of
taxing its digestive system at a rate exceeding what Mother Nature and Evolution had in mind a
million years ago. So the first thing to realize (and imprint in your mind) is that if you're the kind
who loves to feed herps - to watch them feed and grow rapidly, then emeralds ain't your kind of
A good routine is to feed young, growing snakes every ten to fourteen days. Feed sub adults about
the same, although some seem anxious to feed and can be fed more on the eight-to-ten day
schedule if they defecate regularly, exercise, and aren't fed too much at a time. More on that later.
Adult emeralds are another matter. Feed them too often and eventually you'll regret it. Once
regurgitation sets in, it's a slow and difficult syndrome to overcome. A general rule is to feed adult
females every two weeks, and males every three to four weeks. Believe me, they won't pine away
if they're not fed more frequently and most importantly, they'll probably never regurgitate or suffer
any health problems, as long as the other guidelines are followed. There really is no other way to
say it other than adult emeralds don't need much food to remain healthy. Females don't have to be
real heavy to breed, and young snakes grow slowly and should be fed accordingly. Forgetting to
feed them is more of a blessing in disguise. I oftentimes let mine go without food for a month or
more; and it seems to do them nothing but good!
Rule 4 Don't Feed Large Prey
By this I mean don't feed mice or rats with a mid-body diameter larger than that of the emerald's
stomach region. I have 7 1/2' emeralds which are fed one medium-sized rat every two or three
weeks, and two of them are currently gravid and doing just fine. My favorite emerald meal is one
that makes a barely noticeable lump - or NO lump at all - in the snake after feeding. And this does
not mean one should feed a bunch of small mice or rats to make up the difference, either. A three
foot emerald will grow fine on one adult mouse every two weeks. A five foot snake will do well on
a small-to-medium (75 g.) rat, and a seven footer thrives perfectly on one medium (175 g.) rat
every few weeks. Never feed large emeralds jumbo rats. It's a great way to ruin a perfectly good
snake, which isn't about to grow another inch in the next ten years anyway!
If you mess up and can't resist the temptation, you may be confronted with a bloated emerald one
to three days after feeding. Usually this results in a regurgitation. It sometimes can be avoided if
caught early, by lowering the snake's cage temp to the low seventies until the lump disappears. But
if it doesn't work, and the snake regurgs, a little patience and common sense will go a long way
It's best to wait at least ten days after a regurgitation before offering more food, even if the snake
is hanging in the "S" shaped striking coil every night, hunting for a meal. Let the stomach settle
down and then offer it a small meal - a very small meal. Then wait ten to fourteen days and offer it
another small meal. Wait ten more days and feed again, sticking to small rodents all the time. In
almost all cases it's best to maintain this regime for six months or longer before cautiously upping
the prey size. Rushing matters could easily result in further stress to the gastrointestinal tract, which
could eventually become too dysfunctional for the snake to survive. Patience is the key, and if
carried out fully this method (knock on wood...) has yet to fail me. I have one emerald here that
was given to me, a four foot male on death's door at the hands of an over-zealous keeper,
representing nothing but a mass of regurgitating skin and bones. He's been here almost a year now,
and except for one initial regurgitation he's been holding meals down, is gaining weight, and
generally acts very healthy with bright, clear eyes and a constant willingness to feed. I figure he's
still more than a year away from good health, but he represents a labor of love that will be
extremely rewarding when he's 100%.
They key is to understand the nature of the problem and act appropriately, before it's too late. You
cannot force recovery on an emerald. It takes time, and lots of it. My favorite line is to look at a
feed card, notice that it's been oh, say 17 days since the emerald's last meal, and say "I'll feed you
next week!" Let me make it painfully clear: If you're the type who anxiously awaits the next
scheduled feeding with great anticipation, then emeralds are not the snake for you. There's so
much to enjoy about keeping emeralds that frequent feedings should become a secondary activity.
Rule 5 Three Meals, Defecate. Three Meals, Defecate...
The subtitle should be self-explanatory. Anyone who has kept emeralds knows they don't "go" that
often, making cage cleaning - or the lack of it - a joy on most days. With somewhere around 35
adult, juvenile, and subadult emeralds here at most times, oftentimes there isn't a single cage to
clean on a given day. That's truly a keepers delight!
There are three keys to regular defecation in emeralds: exercise, moisture, and not overfeeding.
Exercise is the topic of rule six, but suffice it to say that exercise assists all animals in making
regular, healthy bowel movements. Whether it's your dog or yourself, exercising helps keep bowel
contents in motion and seems to assist in waste evacuation.
It's just as important to monitor defecation in emeralds as it is to keep track of feeding dates. If
you aren't inclined to keep track of waste production, it's fairly easy to observe the animal's general
body weight. If it gets excessively bulky - especially near the cloaca - the chances are it's retaining
fecal mass and would benefit from a bowel movement. Most times, if emeralds are active enough,
they defecate regularly on their own, which seems to occur after every third regular-sized meal. If
not, increase cage size, increase misting, or decrease feeding. Of course, if you're feeding very
small sized meals the animal might likewise defecate less often.
Emeralds can, and sometimes do regurgitate if they haven't defecated recently. It might sound
strange, but it would seem that if their intestine is packed from end to end that the stomach is less
capable of holding a meal. Like I said, it sounds strange but I have seen emeralds regurg, soaked
them in water to induce a BM, and had them hold subsequent meals down with no apparent
difficulty. Whatever ...
That brings up the topic of soaking. If you have to soak an emerald every time to induce the
normal bowel function, something isn't right. I soaked two animals in the last year, indicating that,
for the most part, my animals are doing just fine. Neither of the soakers were repeats, so they
passed their feces and resumed subsequent normal function. If the need arises, soak an emerald in
water a few degrees warmer than ambient temperatures, and keep an eye on it while soaking so as
not to have the poor snake lying in it's own waste any longer than necessary. Rinse the snake and
you're done. It only takes an inch or so of water to elicit the desired behavior, so there's no need to
make a soaking chamber any more stressful than necessary.
Emeralds usually defecate in the early evening, oftentimes just after a misting. If you have an
animal which is overdue, a full cage misting will often induce vigorous activity, which might result
in defecation. Regardless of how it's accomplished, don't feed an emerald more than three meals in
succession without making sure it defecates. If it doesn't, make adjustments to it's living conditions
so that it does.
Rule 6 Coils of Steel! Exercise!
Increasingly, herpetoculturists are subscribing to the holistic school of animal husbandry, where
large display cages with natural decorations are utilized. Animals enjoy a more complex existence if
their cages are large and roomy, and full of interesting objects like rocks, limbs, plants and natural
bedding material. For those who believe snakes are too dull and unexciting to enjoy these
distractions, why don't you just ask your snakes? Let me illustrate.
I recently picked up a very nice male diamond python from a keeper who kept him in a glorified
box, complete with a plastic hide chamber, a water bowl, and a newspaper substrate. Pretty boring,
to both the snake and the keeper - if you ask me. I told him that diamonds are quite arboreal if
given the opportunity (as are their close relatives jungle carpets) and he indicated he wasn't aware
of that behavior. They breed either way, so why bother?
He was selling the animal because it wouldn't breed. I credit him for being honest enough to inform
me of the situation, but I was intent to bring the beast out of the animal. I set him up in a cage like
all my diamonds. It was a roomy four feet long, 34 inches tall, and 32 inches deep (He was a small
animal). He had two limbs to perch on, a large rock in one corner, a small log in another, and a
cork bark hiding place. A small ficus tree graced the middle of the cage, and a shelf with a
screened outside window was included so the snake could bask in real, honest-to-goodness
morning sun. It was like the difference between Motel 6 and the Sheraton. He bred several times
this winter and is soon to be the father of his first clutch of diamond python eggs.
Likewise, my emeralds are maintained in cages just as large, with at least two or three live plants
per cage, a branch-level watering cup (because they will drink from it), VitalitesR, several sized
branches from which to choose (and they almost always choose the highest and smallest),
sufficient room to move, and enough plants to hide within that I sometimes wonder where they've
all gone. But every night, just after dark, their heads begin popping down, as they begin their
almost ritualistic waiting game, poised, anticipating a mouse or rat to appear for a quick strike and a
tasty meal. It is then you'll enjoy your emeralds the most, under red night lights, as they hunt.
Not all emeralds will use the space available to them, but most of them are seen cruising around
their cages periodically, and they frequently change resting limbs for no apparent reason. Even
gravid females, which seem somewhat uncomfortable as they swell, move about quite a bit. It
probably helps gestation to provide the female room for activity.
In contrast is the emerald which is raised in a relatively small enclosure, with one limb and nothing
to stimulate it's instinct to roam and to hunt. I sometimes allow my snakes to travel to other cages,
by utilizing trap doors between them. It's interesting to see that sometimes they'll trade cages and
seem more content in another snake's cage than their own. One might speculate the "grass is
greener" isn't a saying true only for horses...
Exercise is good for an animal's defecation function, as formerly discussed. It is also good for
muscle tone and conditioning. It aids an animal's general well being in ways we can only speculate,
but one thing is for sure: They do better, not worse, in large, interesting cages.
When an animal is maintained more than "just adequately" the problems most often associated
with husbandry are frequently minimized. I get many calls each month from emerald keepers,
almost always related to not feeding or to regurgitations. That's what prompted me to write this
article, in hopes of helping current emerald keepers, as well as prospective aficionados of these
wonderful snakes to keep them successfully. The rules described here are merciless. Violate
them and your emerald will most likely suffer. While the occasional keeper reports success with
slight variations in these procedures, they are the exception, and not the rule.
Remember: Nature designed this art deco animal more than a million years ago - far longer than we
have been keeping them in captivity. It comes from a warm and fairly stable environment, where
the relative humidity ranges from high to higher. The days are always twelve hours long, and the
nights are likewise twelve hours in duration. It primarily preys upon arboreal rodents, and it
probably doesn't eat very often, since it is an opportunistic feeder. An emerald tree boa's idea of
hunting is to hang down a foot or so from it's resting position and wait for something to come along
(reminds one of the vulture poster which says: "Patience my butt, I'm gonna kill something!"). The
emerald tree boa is definitely NOT an aggressive seek and kill animal, like a bullsnake wiping out
nest after nest of rats in the local barnyard.
Nature evolved the emerald tree boa to knock the emotional socks off guys like me, I'm sure of it.
Ever since I first saw a photo of one in "Living Reptiles of the World" (Schmidt & Inger, circa
1955) it has been my passion to be near these beautiful snakes. To do so we owe them our best
attempts at proper husbandry. The Amazon Basin Corallus canina is an amazing snake, strangely
blessed with a timid and docile nature, an obvious choice for many reptile keepers. Treat them well
and they'll outlive many herps in your collection, and give you immeasurable hours of satisfaction
along the way.
Last year a freak incident occurred at our facility. The pictured Surinam female, purchased gravid
from the wild, gave birth to eleven (11) atypical offspring. It is believed she must have bred with a
Cook's tree boa, perhaps in the South American compound, or that possibly this is the result of a
wild integration of the species.
The entire birth sequence was witnessed and photographed, and some of the photos are shown
here to record this unique event.
Eight months later the young are growing and exhibiting extreme variance from each other -
ranging from gray and lavender, to red and yellow, to orange spotted, to yellow spotted. As they
grow they continually get more attractive and breeding the sibs together will result in
who-knows-what? While the author isn't the least interested in hybridizing, this mysterious event of
unknown origin demands further attention. The likelihood that this breeding occurred in the wild is
very high, since the animals aren't held that long after capture before shipping. Emeralds, with a
gestation of approximately seven (7) months, would unlikely be kept anywhere near that amount of
time in Surinam. The birth occurred about a month after purchase, so these unusual neonates
might represent a natural hybrid. We're still waiting for DNA results to possibly identify the sire's
Kamuran Tepedelen, of Bushmaster Reptiles, had a similar single neonate born with a litter of
normal Surinam emeralds in 1996, also from a wild caught female. It bears a remarkable
resemblance to these babies and further poses the question of hybridization in the wild. Perhaps
not all Cook's or garden tree boas are what we think they are...
A Little Sidebar
How to Feed Baby Emeralds
One thing in particular is very important to realize: emeralds are highly keyed to their labial heat
pits for feeding. Whether as babies or as adults, warm prey items are by far the most preferable.
While they can be weaned on to feeding prekilled, and even frozen and thawed mice or rats, their
preference is for live, hot mammals.
Pinkie mice are NOT a preferred food item for emeralds. This is probably logical, since emeralds
aren't the kind of snake that would invade a rodent den to find food, as would many other kinds of
baby snakes. They most likely take small hopper sized mice right after birth, mice that would be
wandering the forest floor within striking distance of baby emeralds. Although it hasn't been
documented yet, baby emeralds most likely feed on basking lizards for their first meals of life.
Nevertheless, starting them on mice in captivity is relatively easy.
There are two reasons for starting emeralds on hoppers: first of all, baby emeralds are quite large
and can readily handle larger meals, unlike Chondropytho ssp.hatchlings. Secondly, hoppers offer a
more attractive "target". Pinky mice don't give off much body heat, whereas hopper mice do. A
common mistake is for keepers to try to feed pinky or small fuzzy mice to baby emeralds, and
there just isn't enough heat and activity from the prey animal to interest them! It's amazing how a
reluctant feeder will turn on instantly to a larger, warmer mouse!
Caging is critical to food presentation. One of the best setups is the 12 inch Bush, or Neodesha
unit. It's easy to provide a perch about two to three inches over the cage floor, where baby
emeralds can avoid being bothered by a hopper; but at the same time can just as easily make a
killing strike with little effort. It's important to make it easy for the snake to see, heat sense, and
approach the mouse without being spooked in the process.
Keeping the snakes over water, an oftentimes preferred method, poses feeding problems for
neonates. By using carpet, cut to the cage bottom size, and then kept wet the humidity
requirements of the emerald can be met, while offering the hopper a relatively dry surface to move
about on before it's arboreal demise. Once an emerald has become an active feeder, they can be
transferred to larger caging with even wetter substrate, if needed.
Reluctant feeders happen from time to time. One of the wonderful things about emeralds is that
you don't have to force feed them. "Assist" feeding becomes an easily facilitated option. Assist
feeding is accomplished by gently holding the snake and pushing a fresh killed fuzzy into its mouth.
Be patient, it may take some time. Hold the snake behind its large jaw muscles and begin pressing
the mouse up to its mouth. The little bugger will eventually open up and take the mouse. Now is
when the patience part really comes in! Watching a favorite TV show while performing this
operation is the best way to wait the snake out. I like to watch the Animal Planet channel, so the
snake can also enjoy the program.
If the snake trys to eject the mouse, keep it in its mouth - not by forcing, but simply by keeping it
there. Allow the snake to move back, but keep the mouse in its mouth. Eventually, and it
sometimes takes more than ten minutes, the snake will give up trying to eject the mouse and will
begin to swallow. Most reluctant feeders start feeding on their own after a few of these sessions.
Remember to give them a voluntary try after a time or two of this method! It helps to let them go a
few weeks without a meal to increase their hunger - similar to what they might experience in the
wild. And use small fuzzies, they're a lot easier for reluctant feeders to swallow.
One Gently push the mouse against the emerald's mouth, it will take it.
Two Don't let the snake spit it out, keep it there no matter what. Note size of food item.
Emeralds naturally feed best at dusk, the period of a few hours just after the sun goes down. It's
best to capitalize on this tendency and feed them at that time. Conversely, it is difficult to get them
to feed during daylight hours, when they're usually in a deep sleep. Once an emerald takes its first
meal, they quickly become savage feeders and both the keeper and the emerald are a lot happier.
You can then watch Animal Planet all alone, unless your snake wants to watch too.
Another Little Sidebar
It seems like a simple enough topic, but improper caging will cause emeralds more problems than
you might imagine.
Remember one very important thing: emeralds need high humidity to stay healthy. It keeps their
lungs from giving off too much moisture (just like humans) and reduces their chances of
developing respiratory problems. But humidity must be cycled, that is, from high during the day to
low at night. And the cage must have ventilation, to prevent the air from stagnating.
My cages have screen tops and sometimes even screen fronts. As a result the air is always moving.
They are sprayed in the morning and again in the evening to keep the humidity high. Living in
Colorado, where the air is very dry, requires that much humidifying! If you live in a humid place,
you might be able to spray very little and still maintain proper levels for emeralds.
One way to keep the humidity high during the day is to cover the screen top with a plastic sheet,
which can be removed at night to allow the humidity level to drop. In my case, I keep the entire
room (since it's filled with only emeralds!) humid, by soaking not only the cages, but the floor and
planters. At night, it dries nicely and I repeat the cycle the next morning.
Actual cage design is up to you. I'll show some photos of some of my home built cages to give an
idea of size and layout. Remember to give them lots of room, because they need the exercise. I
waterproof my cages with fiberglass epoxy resin (finishing) and they're as watertight as glass
Using a substrate like mulch increases the surface area of wetness, so-to-speak, and gives off a lot
more humidity than simply wetting papers or keeping a large water bowl in the cage.
People always ask for cage dimensions, so here they are:
Baby emeralds A five gallon tank will do fine, or something measuring about 12" long, 8" wide,
and about 10-12" tall. Don't put baby emeralds in too small a cage, or they will never notice food
animals in the bottom! You can keep the snake in this cage for one year.
Yearling emeralds A ten to twenty gallon tank is fine, or dimensions of 24" long, 15" wide, and
up to 24" tall. Make sure the animal has plenty of room to roam and that there is more than one
branch for it to use.
Adult emeralds Forget the aquariums at this stage. Adult emeralds need space, and my cages are
between 36-48" long, and as high as 42". If I had more room, I'd make them even larger. Lots of
branches are great, as adults need as much room to roam as do youngsters.