Download Advanced Snakes - The Maryland Zoo in Baltimore

Module 2.5: Advanced Snakes
Interpretive Guide
Interpreting With Snakes: The theme of your conversations may differ from group to group
depending on the program, the age of your audience, or your audience’s perceptions of snakes.
Examples of different talking points that relate to Zoo themes are listed below.
Theme: Humans and wildlife can coexist.
Background: Snakes often have a bad reputation for being scary, slimy and dangerous.
Changing the negative perception of snakes is important for their survival; some people who
fear snakes prefer that they are not in their garden or near their home, and may take extreme
measures to remove them.
Talking point: Dispelling fear of snakes



Possible hook: Do you think snakes are scary?
Related facts:
o There are 27 snake species native to Maryland; only two are venomous
(copperhead and timber rattlesnake).
o Snakes aren’t typically aggressive towards humans. Many snakes have
adaptations (eastern hognose, Pueblan milksnake) that make them appear to be
much more dangerous than they are.
o Snakes eat common household pests, like mice and rats (and other snakes, when
handling the kingsnakes).
Possible calls to action:
o If you spot one in the wild, simply maintain a safe distance or allow it to move
away from you. In more extreme cases, contact DNR or visit wildlifehelp.org
o Encourage visitors to explore the exhibits in Maryland Wilderness to learn about
Maryland native snakes.
Theme: Living things exist within complex relationships in ecosystems and are adapted for
survival in their habitats.
Background: Discussions about adaptations and ecosystem interactions (predator/prey,
keystone species, scavengers, etc.) fall under this theme. Some examples are listed below.
1. Talking point: Eastern hognose snakes have adaptations for hunting toads.
 Possible hook: What do you think this snake eats?
 Related facts: (see Eastern hognose factsheet for more detail)
o Rear fangs, specialized hormones, amphibian-specific toxin
12/20/2016
Interpreting with Snakes
The Maryland Zoo
Module 2.5: Advanced Snakes
Interpretive Guide
2. Talking point: Non-venomous snake hunting adaptations (see snake basics; relevant for all
embassy snakes)
 Possible hook: How do snakes catch their prey?
 Related facts: (check factsheet for species specific information)
o Camouflage
o Jacobson’s organ
o Constrictors
o Specialized jaw bones
Theme: Humans are part of the rich diversity of life, and have the power to protect or destroy
it.
Background: Sometimes human activity can negatively impact or threaten wildlife. The talking
points below describe some threats that snakes face in the wild, and how we can help to
prevent these issues.
1. Talking point: Snakes as pets
 Related facts:
o Over collection of wild snakes for the pet trade threatens many snake species.
o Snakes require specialized care (housing, diet, temperature requirements).
o Snakes often live longer than we might expect and some species grow quite
large.
 Call to action: Make responsible pet choices; if you do decide that a pet snake is right for
you, make sure you have plans to properly care for it for its entire life.
o Purchase pets from responsible breeders; do not purchase wild-caught
individuals, or take snakes from the wild.
o Research the species lifespan and average size
o Research the needs of the species (diet, housing, temperature requirements)
2. Talking point: Snake skin products put pressure on some wild snake populations
 Related facts:
o Snakes are covered in scales; the color of scales often provides camouflage or
serves as warning coloration.
o Several species are collected and killed for leather products (ex. see blood
python and Dumeril’s boa factsheets).
o Snakes are important to have in the environment – they keep rodent
populations in check.
 Call to action: Know the origin of the products you buy – opt for fake leather over snake
skin products
12/20/2016
Interpreting with Snakes
The Maryland Zoo
Snake Basics
Interpretive Guide
Snakes are Reptiles:
Reptiles are cold blooded, or ectothermic. This means that they rely on outside sources to
warm or cool its body. A snake can often be observed basking in the sun, or resting on hot
rocks for warmth. If a snake is too warm, it may retreat to a cooler place, like a burrow or
shaded area. Because it spends less energy warming and cooling its body compared to a
warm blooded, or endothermic animal, such as a human, it requires less food.
*Fun fact: Depending on their size, snakes at the Zoo are offered food only once a week,
or once a month!
Jacobson’s Organ:
Snakes have a special organ called the Jacobson’s organ that helps them smell, or “taste”
the air. The Jacobson’s organ is a major component of the snake’s hunting ability, and is
also used to detect pheromone communication from other animals.


The Jacobson’s organ is an extra olfactory organ located in the skulls of many animals,
including snakes. It functions much like a nose—when the snake sticks its tongue out, it
grabs molecules of air that it then transfers to the Jacobson’s organ, allowing it to
“taste” the air.
Snakes do have noses, and can smell with them. The Jacobson’s organ increases the
amount of information taken from the snake’s surroundings, allowing it to better
pinpoint its prey.
Constricting Prey:
Some snakes kill their prey by delivering a venomous bite. We do not have venomous
snakes in the Embassy, all Embassy snakes are constrictors. After seizing a prey animal with its
small, needle-like teeth, a constrictor will wrap its body around the prey and squeeze. This does not
crush the animal; instead it prevents the prey from obtaining enough oxygen. Once the prey has
suffocated, the snake will begin to consume it.
Specialized Jawbones:
Unlike humans, snakes have extremely flexible tendons attaching their lower jaw to the rest
of their skull, allowing them to dislocate their mandible in order to swallow relatively large
food. Additionally, their chin contains flexible elastic tendons. Due to this flexibility, they
can open their mandible sideways, further increasing the possible size of their food.


Rhythmic muscular contractions help to push food down their throats and into their
stomachs.
When eating large food, a tube in their mouth will move to the side and allow for
continued oxygen exchange. Without the tube, a snake eating a particularly large food
item could suffocate.
12/20/2016
Interpreting with Snakes
The Maryland Zoo
Blood Python
Python brongersmai
Description:
 Size:
o Typically reach 4-6 ft (1.2-1.8 m) in length
 Weight: Typically weigh 12-20 lbs. (5.4-9 kg)
 Physical Description: A thick, heavily bodied snake with a long, flat head, and a short tail.
o Called “blood pythons” because of their reddish-rust coloration – which can be
brick-red in some individuals – with splotches and stripes of yellow, tan, and
black
o Head is dark grey or brown; belly is white and sometimes has black markings
 Sexual dimorphism: Females are usually larger overall than males but males generally
have longer tails
In the Wild
Habitat and Range:
 Range: Native to Southeast Asia in southern China, Malaysia, Sumatra, and Borneo
 Habitat: Found in a variety of habitats including rainforests, marshes, swamps and palm
oil plantations – prefers areas near rivers and streams
Diet:
 Carnivorous: Eat rodents such as mice and rats, and occasionally eat birds
Adaptations:
 Ambush predator: lies in wait, sometimes in a river or stream, for prey to get close
before striking
o Remains motionless for long periods of time while waiting for prey to approach
o Uses eyes and tongues to sense their prey
o Also use heat-sensing pits in the upper lips to identify warm-blooded prey items
 Camouflage: Their cryptic coloration allows them to camouflage in order to hide from
both predators and prey
Lifespan:
 About 15-20 years, can live up to 35 years of age
Ecosystem relationships:
 Predators: Young individuals are susceptible to predation by hawks and other birds of
prey, other snakes, and crocodilians
 Role/ Niche: Function as a control on rodent populations
Reproduction:
 Incubation: Unlike most snakes, the female remains with the eggs for about 3 months
12/20/2016
Blood Python
The Maryland Zoo
Blood Python
Python brongersmai


and incubates them by coiling around them and “shivering” to keep them warm –
incubation takes a great deal of energy and can cause females to lose up to half of their
body weight
Clutch Size: Females lay up to 10-15 eggs about 3 months after mating
Maturation:
o The female leaves the hatchlings to fend for themselves
o Hatchlings are typically 15-18 in. long and are tan with black markings
o Reach sexual maturity at 2-3 years of age
Activity:
 Nocturnal: Most commonly active at night, where they remain partially submerged on
the edges of slow-moving rivers and streams or in pools while waiting for prey
Other “fun facts”:
 Also sometimes called short pythons, short-tailed pythons, red blood pythons, and
Malaysian red blood pythons
 Pits in the roof of the mouth suggest that pythons are descended from a venomous
ancestor.
 Pythons vs. boas
o A major difference between pythons and boas is that pythons are oviparous,
which means that they lay eggs, while boas are ovoviviparous, and young hatch
from eggs inside the mother’s body.
o Pythons are found exclusively in the old world (Eurasia, Africa, and Australia),
while boas are found throughout the world, but chiefly occupy the new world
(the Americas)
Conservation Status and Threats:
 Listed on IUCN Red List as Least Concern
 Listed on CITES Appendix II
 Threats:
o Over collection for the international pet trade
o Often collected and killed for leather products – estimated that about 200,000
individuals are killed for their skins each year
 Despite threats, populations are thought to be increasing in size because they are
successfully establishing populations in palm oil plantations which attract rodents
o Although the increase in palm oil plantations may benefit blood python
populations, a 2007 report by the United Nations Environment Program showed
that palm oil plantations are the leading source of rainforest destruction in
Malaysia and Indonesia, home of endangered animals such as orangutans and
Asian elephants
12/20/2016
Blood Python
The Maryland Zoo
Blood Python
Python brongersmai
At the Zoo
Monty came to the Maryland Zoo from a private breeder in August 2012. He hatched around
May 2012.
What We Can Do



Make environmentally responsible lifestyle decisions to help conserve habitat –
conserve energy, reduce litter, and pollution
Make sure you know the origin of the products you buy – buying something imported
illegally supports the black market by sustaining demand
o Ex. Rosewood is still being illegally imported from Madagascar despite bans on
logging because people are still buying it
Do your research before buying a pet
o Make sure you are not purchasing a wild-caught individual – go to a responsible
breeder.
o Make sure you know how to properly care for any animal before you decide to
buy it as a pet
 Some things to consider include adequate housing, diet, temperature
requirements, and lifespan
 Some pets also require a lot of time and money to be properly cared for
Additional Resources and References:
 Denver Zoo:
http://www.denverzoo.org/downloads/animal_fact_sheets/Reptiles/Python_blood_.pd
f
 IUCN Red List:http://www.iucnredlist.org/details/192169/0
 Brandywine Zoo: http://www.brandywinezoo.org/blood-python.html
 Better Palm Oil: http://www.betterpalmoil.org/
 Roundtable on Sustainable Palm Oil: http://www.rspo.org/
 Staffors, Peter J. Pythons and Boas. Neptune City: TFH Publications, Inc., 1986. Print.
 Mehrtens, John M. “Living Snakes of the World”
12/20/2016
Blood Python
The Maryland Zoo
Dumeril’s Boa
Acrantophis dumerili
Description:
 Size:
o Typically 4-6 ft (1.2-1.8 m) long
 Maximum size is about 7 ft (2.1 m) long
o Weight: Typically less than 20 pounds (9 kg)
 Physical Description: A medium-length, thick bodied snake.
 Coloration varies
o Typically brown with a slight pinkish tinge
o Head is decorated with brown “bridle” stripes that break up the snake’s outline
o Pet trade breeders may create new color morphs that are not seen in wild
populations
 Sexual dimorphism: Females are generally larger than males
In the Wild
Habitat and Range:
 Range: Native to south and southwestern Madagascar
 Habitat: Prefers dry, open forests in southern localities, and savannah in the northern
parts of their range
o Prefers to rest in tree roots or abandoned burrows
o Can live in areas disturbed by human activity as it more difficult for prey animals
to hide
Diet:
 Carnivorous: Primarily consumes small mammals, particularly rodents
Adaptations:
 Mottled brown, black, red, and white coloration serves as excellent camouflage in leafstrewn ground
 As constrictors, boas lack fangs and instead have numerous small teeth that grip their
prey and prevent escape
 Can detect both vibrations in the ground and sound vibrations through the air through
their jaw bones
Social Structure:
 Solitary; only social during mating season
Lifespan:
 Typically live 20-30 years
Ecosystem relationships:
 Predators: Few, mainly introduced cats and dogs. Young are more likely to be eaten
12/20/2016
Dumeril’s Boa
The Maryland Zoo
Dumeril’s Boa
Acrantophis dumerili

than adults.
Are important predators of small mammals, many of which are invasive to the island of
Madagascar
Reproduction:
 Breeding Season: Spring, typically after a two-month brumation
o Behavior: Males may fight and injure each other in order to gain mating rights
with a female
o Males use spurs, which are small vestigial projections near their pelvis, to
stimulate receptive females prior to copulation
o Several males typically mate with one female
 Incubation: Females are ovoviviparous; instead of laying eggs, the eggs incubate inside
the female’s body, hatch, and then are born live.
o Eggs incubate in the female for 4-7 months.
 Clutch size: 6-8 young per clutch
o Small clutch size is likely due to the relatively low populations of natural
predators
 Maturation:
o Young are much larger than typical for a snake of its size, being up to 1.5 ft (48
cm) immediately after birth
o Reach sexual maturity at 3-5 years of age
Activity:
 Cathemeral: Intermittently active during day, night, or twilight
 Brumate during the colder months – brumation is a process reptiles go through that is
similar to mammalian hibernation
Other “fun facts”:
 Dumeril’s boa and the closely related Madagascar ground boa (A. madagascariensis) are
the only boas in the Acrantophis genus, and are believed to have evolved from a
common ancestor before Madagascar split from Africa
 Unlike many other boas, members of Acrantophis lack heat-sensing pits on their heads
 Pythons vs. boas
o A major difference between pythons and boas is that pythons are oviparous,
which means that they lay eggs, while boas are ovoviviparous, and young hatch
from eggs inside the mother’s body.
o Pythons are found exclusively in the old world (Eurasia, Africa, and Australia),
while boas are found throughout the world, but chiefly occupy the new world
(the Americas)
Conservation Status and Threats:
12/20/2016
Dumeril’s Boa
The Maryland Zoo
Dumeril’s Boa
Acrantophis dumerili





IUCN list as Least Concern
o The species has a wide range, is fairly tolerant to habitat disruption, and not
endangered by any significant threats
Listed under appendix I of CITES, which is typically reserved for the most endangered
plants and animals
o Though considered common throughout its range, the home range of Dumeril’s
boa is the island nation of Madagascar, which contains several unique
environments that can be easily disturbed, warranting the protection of many
native animals
o International trade of captive-bred boas is still permitted, though heavily
regulated
Somewhat conservation dependent—many of Madagascar’s forest have been cut down,
leading to a loss of habitat for these animals. Many of them live on nature preserves,
and receive protection in those areas.
Are caught and killed in small numbers for a variety of reasons
o Skin is used to make leather products, and in some cases the entire specimen is
used as food
o Is sometimes hunted because it is believed to be bad luck, and likely predates on
domestic poultry
Conservation of snakes is of great benefit since they eat rodents that destroy crops or
spread disease
At the Zoo
Groot was born in 2004 at the Brookfield Zoo in Chicago, where he was regularly handled as a
program animal. He came to the Maryland Zoo in late 2014.
What We Can Do



Make environmentally responsible lifestyle decisions to help conserve habitat –
conserve energy, reduce litter, and pollution
Make sure you know the origin of the products you buy – buying something imported
illegally supports the black market by sustaining demand
o Ex. Rosewood is still being illegally imported from Madagascar despite bans on
logging because people are still buying it
Do your research before buying a pet
o Make sure you are not purchasing a wild-caught individual – captive-bred species
are often easy to find
o Make sure you know how to properly care for any animal before you decide to
buy it as a pet
 Some things to consider include adequate housing, diet, temperature
12/20/2016
Dumeril’s Boa
The Maryland Zoo
Dumeril’s Boa
Acrantophis dumerili

requirements, and lifespan
Some pets also require a lot of time and money to be properly cared for
Additional Resources and References:
 Encyclopedia
Brittanica:http://www.britannica.com/EBchecked/topic/299124/Jacobsons-organ
 IUCN: http://www.iucnredlist.org/details/282/0
 ARKive: http://www.arkive.org/dumerils-boa/acrantophis-dumerili/
 Woodland Zoo: http://www.zoo.org/page.aspx?pid=1938#.VGUQc_nF8vw
 Walls, Jerry G. “The Living Boas”
 Mehrtens, John M. “Living Snakes of the World”
12/20/2016
Dumeril’s Boa
The Maryland Zoo
Eastern Hog-nosed Snake
Heterodon platirhinos
Description:
 Size:
o Length: up to 3.75 ft (115 cm)
 Physical Description: A stocky, medium-length snake characterized by a wide head,
upturned scales on the tip of the snout, and enlarged teeth towards the rear of the
mouth
 Coloration: Two color phases exist:
o Numerous dark blotches arranged in rows that run down the length of the spine
with a background color that may include gray, tan, pink, yellow, orange, and red
o The melanistic (heavily pigmented) phase that is nearly uniform black, with slight
gray peppering on the tail and underside
o The underside of both phases is typically cream to dark gray
 Sexual dimorphism:
o Males typically have longer tails relative to their body length
o Females are longer and heavier on average, and typically have more blotches on
their back
In the Wild
Habitat and Range:
 Range: Found extensively throughout North America east of the Rocky Mountains.
o The species is primarily found north of the Gulf of Mexico into areas of southern
Canada, though they are absent from several areas near the Great Lakes.
 Habitat: Areas with loose, dry soil are the most preferable habitat, though they can be
found in ecotonal areas where differing habitats meet, or in urban areas given suitable
patches of habitat. Avoids aquatic areas except to move between feeding areas.
Diet:
 Carnivorous: Primarily adapted to eating toads and frogs, but they may also consume
salamanders, small birds, mammals, reptiles, eggs, and insects
Adaptations:
 Upturned scales: Scales on the snout are used to push soil out of the way to facilitate
digging
 Adaptations for hunting amphibians:
o Specialized hormones: While many toads secrete toxins through their skin,
hormones produced by hog-nosed snakes neutralize the poison and allow the
snakes to safely consume toads
o Amphibian-specific toxin: The snake’s saliva contains chemical compounds that
serve to subdue amphibian species, though it does not affect most nonamphibian species. Very few humans are affected by this toxin.
12/20/2016
Eastern Hognose Snake
The Maryland Zoo
Eastern Hog-nosed Snake
Heterodon platirhinos

Defensive behavior:
o After being cornered, the first reaction of a hog-nosed snake is to inflate the
head and body to attain a cobra-like appearance, coil the body with an elevated
head, rapidly hiss, and strike without actually biting.
o If this does not deter the intruder, the snake will begin to thrash while defecating
and excreting musk, which is then spread across the snake’s body by its
thrashing motion. It may also vomit its previous meal.
o After a minute or so of this behavior, the snake will lie on its back and become
completely limp. It then stays in this position until the predator has left the area.
Lifespan:
 Wild: Unknown
 Captivity: Up to 11 years
Ecosystem relationships:
 Predators: Any medium to large carnivore, but primarily larger snakes and hawks, may
eat this snake at any of its life stages
 Interspecies competitors: Mainly other predators, including snakes, birds of prey, and
mammalian carnivores
 Role/ Niche: Mostly function as a secondary consumer that suppresses amphibian
populations
Reproduction:
 Breeding season: Spring – eggs laid in summer months
 Behavior: Females deposit eggs in sandy soil or under rocks, logs, etc.
 Clutch size: Typically 15-35 eggs per clutch; can lay as many as 60 eggs
 Incubation: 2 months
 Maturation:
o Hatchlings are 6 – 10 inches in length
o Sexually mature at around 2 years of age, but continue to grow in size for the
entirety of the snake’s life
Activity:
 Diurnal
 Burrowers; will forage for frogs and toads that are burrowed in soil
Other “fun facts”:
 Rear-fangs: Large teeth located near the rear of the mouth are thought to be used to
puncture a toad that self-inflates defensively, though this has never been witnessed
 Other common names include the word “adder” or “viper” – these names are
misnomers, as “adder” and “viper” are typically reserved for highly venomous snakes.
12/20/2016
Eastern Hognose Snake
The Maryland Zoo
Eastern Hog-nosed Snake
Heterodon platirhinos
Conservation Status and Threats:
 Listed on the IUCN Red List as least concern.
o The species has a wide range and is not thought to be in decline. While wild
numbers are not well known, they are almost certainly well in excess of 100,000
individuals, and are fairly common in all parts of their range.
 CITES: no special status
 Conservation efforts:
o There are currently no major efforts directed towards hognose snake
conservation
o Because this snake’s major threat is habitat loss, any initiative the preserves
natural habitat directly benefits this animal
At the Zoo
Vader is the Maryland Zoo’s hognose ambassador. He hatched at Seneca Park Zoo in New York
in August 2008. Eastern hognose snakes are also on exhibit in the Maryland Wilderness.
What We Can Do



Make environmentally responsible lifestyle decisions to help conserve habitat –
conserve energy, reduce litter and pollution
Make sure you know the origin of the products you buy – opt for fake leather over snake
skin products
o All of our shopping choices can have an impact on the environment and wildlife
so when available opt for recycled and local products
o Research responsible companies that do not use animal based products or
testing
Do your research before buying a pet
o Make sure you are not purchasing a wild-caught individual – captive-bred species
are often easy to find
o Make sure you know how to properly care for any animal before you decide to
buy it as a pet
 Some things to consider include adequate housing, diet, temperature
requirements, and lifespan
 Some pets also require a lot of time and money to be properly cared for
Additional Resources and References:




ADW: http://animaldiversity.org/accounts/Heterodon_platirhinos/
IUCN Red List: http://www.iucnredlist.org/details/63820/0
Savannah River Ecology Lab: http://srelherp.uga.edu/snakes/hetpla.htm
Mitchell, Joseph C. The Reptiles of Virginia. Washington, DC: Smithsonian Institution, 1994. 213-16. Print.
12/20/2016
Eastern Hognose Snake
The Maryland Zoo