Venomous Spiders in Texas

Spiders are an incredibly diverse and fascinating group of animals.  As with other venomous creatures, many people tend to be overly concerned about them.  Only two of the 900 species in Texas are truly dangerous and both of them are quite shy and retiring.  Bites do occur but they are rare and usually the result of accidental contact. 

Except for one taxonomic family, all spiders possess venom glands.  By far, the majority of spiders are not dangerous to people although allergic reactions can occur as with wasp or bee stings.  The only spiders of medical significance in Texas are the Black widow (Latrodectus mactans) and the Brown recluse (Loxosceles recluse).  

George the Brown Recluse

The name Black widow is actually a misnomer as the action implied rarely occurs.  Black widows have a potent neurotoxic venom which can be quite dangerous to debilitated persons and young children.  An antivenom is available for Black widow bites if deemed necessary.  Brown recluse venom is a necrotoxin which can cause tissue damage. 

Southern Black Widow

After a male’s last molt he is sexually mature and will spend the rest of his life seeking mates, oblivious to everything else including food.  Most male spiders only live for a few months after their maturing molts.  The male constructs a special sperm web onto which he deposits sperm from his genital opening.  The sperm is then taken up into the pedipalps to be later placed in the genital opening of the female.  After a few weeks the female will construct a silken cocoon in which to lay her eggs which can number from a few to several thousand.

Many spiders guard their egg cases.  Some spiders even exhibit parental care.  A wolf spider female will open the egg sac and allow the spiderlings to ride on her back for a few weeks.  There is even a spider that will regurgitate food for her offspring.

Baby Wolf Spiders on the Bus

We come close to many more spiders than we will ever know because of their size and habits.  These seemingly primitive mechanical creatures actually prove very interesting if one spends a little time observing them.

Jumping Spider - Hentzia mitrata

Written by Judith Bryja, Houston Zoo Herpetology Supervisor

Meet the Staff: Susan Shepard

Susan Shepard

Hometown:  Camp Pendleton Marine Corps Base, CA (Oceanside)

Department/Title: Carnivore Keeper

How long have you worked at the Houston Zoo?: 8 years

How long have you been in the your field?: Total of 11 years – I worked at the Topeka Zoo for 2 ½ years

Animals I train: Patty (Spectacled Bear); Kadu (Leopard); Uzima (one of newest female Lions); Taji (Anatolian Shepherd)

Favorite animal: Spectacled Bears – bears in general!

Animals at home: I have a Blue and Gold Macaw, 1 dog and 2 cats.

Special interests/hobbies: Knitting, reading, hiking, working with Rhodesian Ridgeback and Anatolian Shepherd rescue groups. I also volunteer at a low cost spay/neuter clinic in La Marque.

Spectacled Bear

What made you want to work at a zoo?:

Initially I wanted to be a vet but by the time I would have gotten accepted, I would have had to go to college for 8 years and didn’t want to commit the time. I also knew that I did not want to work with livestock animals as a career. One day a woman from Cat Tales, a private facility in Spokane, WA that specializes in cats, came to the university and did a presentation about cats and zoo keeping. She brought one of their leopards and took him out for part of the presentation. After talking with her I thought Zoo Keeping would be fun to do as a career. I did some research, decided that it was something I wanted to do and switched my major to Zoology.

Education/training: Bachelor of Science Zoology, emphasis on Animal Care from Washington State University and a Certificate in Zoo Keeping from Cat Tales Zoological Training Center.

Advice to anyone wanting to enter your field: Be prepared for a lot of hard work and don’t get discouraged if you don’t get a job right away! Getting a job takes a lot of luck and good timing. You have to work for it and be persistent! If possible, take courses in psychology, training workshops, horticulture, and public speaking.

For Goodness Snakes!

“These foul and loathsome animals…”

Aruba Island rattlesnake

So wrote Carolus Linnaeus in his description of reptiles in his Systema Naturae published in 1735. In fact, throughout much of human history, snakes have been among the most maligned and persecuted groups of animals.

The unreasonable fear of snakes is quite prevalent in our society and myths and misconceptions abound whenever snakes are brought up in conversation. The general public conception is that snakes are the “enemy” and should be killed on sight. It has been estimated that over 50% of our population exhibit some anxiety or nervousness in the presence of snakes while another 20% are terrified, some to the point where even a picture of a snake can cause severe distress (Werler and Dixon, 2000). Psychologists have coined a term to describe this condition (ophidiophobia) and it is considered to be one of the more difficult fears to overcome. 

The news media also plays a role in shaping this attitude. Most publicity concerning snakes is of a negative nature. Venomous snakebites often receive extensive local media coverage far beyond the actual threat to human life. Rarely is it pointed out that the chances of death from a venomous snakebite are considerably less than the chances of dying from a lightning strike or from an insect bite (Bureau of Vital Statistics, Texas Department of Health).

These fears persist in spite of overwhelming evidence, both scientific and anecdotal, on the important roles that snakes play in a healthy ecosystem. Many scientific articles point to the value of snake species in food chains in temperate and tropical ecosystems. Areas where snakes are removed often display a population explosion of rodents, usually to the detriment of nearby agricultural enterprises. For example, the Chinese news agency has reported that the increased intensive hunting of wild snakes for their meat (which is considered to be a delicacy) and other products used in traditional medicines has resulted in a dramatic increase in the rodent population with devastating consequences for the Chinese farmer.

Canebrake rattlesnake

Out of all snakes, the rattlesnakes probably have received more unjust notoriety and have been persecuted needlessly more than any other group, especially in the United States. It is doubtful that any other animal group is more feared or less understood by the general public. This persecution has reached such a point that, in some states (seven, to be exact), “Rattlesnake Roundups” are a popular fund-raising event for organizations such as the local Chamber of Commerce or the Jaycees. The largest of these roundups is held each March in Sweetwater, Texas and shows no sign of diminishing in spite of recent criticism by many private herpetological organizations, various Audubon societies, and by many animal welfare groups.

Slowly, however, the bad reputation that snakes have had is changing, even when rattlesnakes are involved. This can be seen in the ever-increasing numbers of successful herpetological societies that are being established in North America, and also by the increasing popularity of non-venomous snakes as pets.

The Houston Zoo Herpetology Department also is involved in educating people about snakes. Despite the fear that many people feel for snakes, there is, at the same time, a fascination about them and a strong desire to see both non-venomous and venomous snakes up close in a non-threatening environment. This desire is especially strong in the state of Texas, which has more species of snakes (both venomous and non-venomous) than any other state in the Union.

To meet this need, the zoo maintains a large proportion of snakes in its reptile collection. Twenty eight exhibits in the Herpetology building are devoted to venomous snakes of which nine are reserved for different species of rattlesnakes. Sixteen other exhibits are devoted to non-venomous snakes. Over each set of exhibits is a flat-screen monitor which displays a picture of the species, its range, and an interesting fact about the animal.

So, the next time you come to the zoo, be sure to visit the Reptile Building and check out our snakes and learn about this fascinating group of animals!


Werler, John E., and James R. Dixon. 2000. Texas Snakes: Identification,   Distribution, and Natural History. University of Texas Press, Austin, Texas.

An update from the African Wild Dog rehabilitation center at Painted Dog Conservation in Zimbabwe

Here is another update from Xmas Mpofu, head keeper, at Painted Dog Conservation in Zimbabwe. –

“We have received 2 puppies from low veld and are now settled into our Rehab Facility. The 2 were dug out of their den following a rabies out break in that area. The pack members are now dead and the 2 pups are the only survivors. The 2 puppies currently seem to be fit and strong and will be released back into the wild with some of our other Rehab dogs.”

Wild Painted dogs in the enclosure at PDC's rehab center

This is another example of why it is imperative to have a Painted dog rehabilitation center at PDC.  These pups wouldn’t stand a chance in the wild without the rest of the pack.  The rehabilitation center will give them the opportunity to integrate into a new pack and gain the strength they will need to survive in the wild. 

Map of enclosures and PDC's facilities


Chute allowing dogs to move from one enclosure to another

The rehabilitation facility itself is very impressive.  There is a series of 4 enclosures – the largest is 70

Powerful electric fence around perimeter of enclosure

 acres.  All of the enclosures have shift doors and chutes connecting them to one another for easy non-intrusive movement between pens.   There are 4 smaller day pens that allow for closer observation, if needed.  The enclosures all have a very powerful electric fence around the perimeter.  Surprisingly, the strength of this fence is more for keeping animals from the outside out!  The saying “the grass is always greener” applies here.  They have had lions, leopards, other Painted dogs, and elephants all challenging the fence line from the outside, and occasionally the unwanted visitors have found their way in.  Much of Xmas’ day is spent maintaining the perimeter fence line.  

Stay tuned for more of the exciting adventures from PDC.

Impressive news from Painted Dog Conservation's childern's Bush Camp in Zimbabwe

Bush Camp kids

Here is an exciting message from Painted Dog Conservation’s children’s Bush Camp in Zimbabwe. This is an example of the country’s unwavering support for this amazing community-based conservation program.   

“Painted Dog Conservation has been awarded a certificate of recognition for the sterling contribution in conservation education to the Matabeleland North region, the only organisation in the district of Hwange to receive this award. Thank you to everyone who has made this contribution a success.”    Wilton Nsimango, PDC

Yellowstone Travel Program Now Open!

Travel with the Houston Zoo May 17-21, 2011 to Yellowstone National Park for our Yellowstone Bears and Wolves Discovery Tour.

This trip offers premiere wolf and bear viewing opportunities in the country. This program is a must if you are a bear or wolf enthusiast, or are just curious about large predators. Participants travel to the best sites in Yellowstone to view grizzly and black bear behavior as they emerge from months of hibernation, and the interaction of wolves and their prey. You’ll enjoy spying bison and elk calves, the magnificent green-up of North America’s “Little Serengeti,” and famed scenic highlights of the world’s first national park.

There are few places America you can see 4 or 5 different species of hooved animal mingling together, along with top predators, coyotes, foxes, song birds, multiple  species of  birds of prey, and chirping ground squirrels.

Click the highlighted link above or email for more information. This trip is limited to 12 participants and sold out in 2010.

Bear family. Photo USGS

The Frogs and Toads of Panama

We are in Panama today visiting the El Valle Amphibian Conservation Center in the town of El Valle de Anton. A program initiated by the Houston Zoo in 2004-2005. While habitat loss is still considered the most serious threat to the majority of species, especially in the humid tropical forest regions of the world, a fungal disease known as chytrid has been identified as being exceptionally deadly to amphibians, while not seeming to affect other groups of vertebrates – fish, reptiles, birds and mammals. We thought you might like to see some of the amazing amphibians which live in the region:

More than Just 8 Legs – Spiders 101

Jumping spiderMaybe you think they’re creepy crawly or maybe you think they’re fascinating creatures. Regardless of which, spiders live with us, though not often apparent. It can help us appreciate them and be less afraid if we know more about them. And if there are ones to have a healthy respect for, educating ourselves on which those are is a good plan.

A  few quick facts to start:

  • Approximately 41,000 species of spiders have been described thus far.
  • About 900 call Texas home.
  • Spiders are placed in the Class Arachnida which also includes scorpions, mites, ticks, and seven other taxonomic orders. 
  • The lifespan of a spider can vary from a few months up to twenty-five years for female tarantulas! 
  • All spiders are strictly carnivorous. 
  • Most spiders are solitary although a few live communally and cooperate in obtaining prey.

Spiders possess two main body parts: the prosoma (front part or cephalothorax) and the opisthosoma (rear part or abdomen).  Four pairs of walking legs are attached to the prosoma.  A pair of pedipalps are in front of the first pair of legs.  These leglike appendages are used for manipulating prey. 

In the male spider, the pedipalps are used as an intromittent sex organ.  In front of the pedipalps are the chelicerae which are used for defense, subduing prey, and grasping things.  The fangs are housed in a special groove in the chelicerae. 

jumping spider

Although most spiders have eight eyes, some have only two, four, or six.

Some cave dwelling spiders have lost their eyes completely.  Most spiders have fairly poor vision; however, some can see quite well.  Jumping spiders, which actively stalk their prey, have excellent vision.  They also take the award for cutest spider as they will turn their furry heads to peer intently at you.  Spiders breathe by way of tubular tracheae and book lungs.  Book lungs (which resemble the pages of a book) are located on the ventral side of the opisthosoma and allow for air exchange. 

Spiders must molt in order to grow.  The old cuticle separates from the new and about a week later the old skin is shed.  Spiders are extremely vulnerable right after molting and until the new cuticle hardens.

a stitch in time
Silk is produced in glands at the rear of the abdomen.  The glands end in spigots at the end of three pairs of spinnerets.  Spider silk is incredibly strong.  It is used for snares as well as draglines and egg cases.  Female spiders have a special gland specifically for producing egg sac silk.  The spiral orb web is the most well known type of web.  One of our most eye catching natives, the yellow garden spider (Argiope aurantia), can be seen resting in an orb web with a zigzag in the center.

Written by Judith Bryja, Houston Zoo Herpetology Supervisor

What Really Matters

It can be overwhelming. Every media outlet you turn to – all the messages are negative. Crime, economy, natural disasters…so we shut down mentally.

At the zoo we talk about the struggle to preserve wildlife and wildlife habitat. People need to see what is going on in the world, but you need to see the positives as well.

In Rwanda, a team of field veterinarians are tending to the health of Mountain Gorillas. In Zimbabwe, education bush camps are teaching children to protect Painted Dogs.  In Texas, the Houston Zoo and partners are reintroducing Attwater’s Prairie Chickens and Houston Toad back into native habitat. In Botswana, our partners at Cheetah Conservation Botswana are helping to protect the health of the communities’ domestic animals and working side-by-side to ensure the safety of their livestock. At the zoo, we recycle and reduce our landfill waste stream. 

A colleague once said to me Human nature does not program us to be proactive until it is almost too late. Well that is dissapointing. What really matters is for everyone to do something positive, just one thing. What really matters is that one thing can ultimately lead to a larger chain of events.

Find one minute a day to step back and look around – have you ever just stopped to watch the birds or butterflies in your neighborhood?  A recent poll found Houston #3 on the list of most stressful cities. We work too much, do not get outside enough (it’s hot, it’s humid, it’s buggy – I get it). But if you take a moment and find one minute a day to do that one simple positive thing – that is what really matters.

…and now for your viewing pleasure, a random photo of a mountain gorilla and his very engaging feet…

Introducing Penelope and Olivia-Guinea Hog Piglets at the Houston Zoo!


Penelope (right) and Olivia enjoy snuggling together, even on hot summer days!

Guinea Hog piglets. Just saying that now brings a huge smile to my face, and I’m not the only one.  Our new girls have charmed every person-young or old, zookeeper or not-that has laid eyes on them.  They now have adorable names to match their very individual personalities: Penelope and Olivia.  Named after two famous piglets from children’s story books, Olivia was named such for her dainty, princess-like personality.  Penelope, on the other hand, goes by the nickname “bulldozer”, always trying to push her way to the center of attention. If these first few weeks of Penelope and Olivia being on exhibit has taught us anything, it is definitely that piglets have a TON of energy!  These girls seem to be on the move the majority of the day.  Running, chasing, bouncing off of each other, training, climbing in water bowls and searching for snacks in the dirt sure takes a lot of energy!  Even eating is a mini-marathon, each piglet trying to play and eat at the same time.  And when they are tuckered out they find a corner to snuggle in, sometimes nose to nose, other times side by side.

Play or eat? Decisions, decisions.

Even the other animals who live nearby are entertained by their antics.  The first few days on exhibit piqued everyone’s interest and nearly every move they made was being carefully watched.  Crowds of goats gathered at the fence, each one trying to get a good look at the new additions.  The Zebus called out, seeming to wonder why the attention was not centered on them, and the Llama couldn’t decide if the piglets were friend or foe.  A week later, everyone is content with Penelope and Olivia being their new neighbors.   When it is time for a training session, the excitement is easy to see.  Penelope and Olivia can’t get enough affection and attention, and they usually greet their trainers with a grunt or squeal.  According to trainer Amy Lavergne, Penelope and Olivia’s favorite reward seems to be strawberries, although being pigs they will accept almost any fruit or vegetable we give them!  Pigs are not picky.  One of the girls’ favorite behaviors to work on is paint, where the trainer applies non-toxic paint to their snouts and lets them go wild on a canvas to create their own masterpiece.  Ok, maybe they don’t go wild yet, but they’re working on it.  And just like your kids at home, they do not like cleaning up!  Running around with a bright pink nose is much more fun than taking a bath.  Before too long they will be learning to walk on harnesses to get some exercise and excitement outside of their exhibit.

Candace applies animal friendly paint to Olivia’s snout, which she will use as her paintbrush.
Olivia makes her first swipe onto the canvas.
She seems to be catching on to the fun of being an animal artist!
She even managed to get some good snout prints!
A completed painting by Olivia
Next up is bath time to clean all that paint off!

For now, Penelope and Olivia are very busy exploring, playing, tasting new foods, learning new behaviors and getting used to their daily routine.  They are absolutely adorable and quite rambunctious, qualities that are sure to make them a Houston Zoo favorite for many years to come!   Be sure to visit the John P. McGovern Children’s Zoo during your next visit to see Penelope and Olivia up close! For more adorable pictures of Penelope and Olivia visit the Houston Zoo’s Photo Albums!

To learn more about Olivia books by Ian Falconer, visit Visit to learn more about Penelope Pig books by Nicole Rubel.

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