The Goliath bird-eating spider is the largest spider in the world by mass and size. Its scientific name is Theraphosa blondi and it belongs to the tarantula family Theraphosidae. These spiders are native to northern South America but are also found in Central America. Despite their name, Goliath bird-eating spiders do not typically eat birds, though they are capable of killing and eating small birds, mice, lizards, and frogs. Their diet mainly consists of insects and other invertebrates. Let’s dive into the details about how big the biggest Goliath bird-eating spider can get.
Leg Span
The Goliath bird-eating spider has a leg span that can reach up to 12 inches (30 cm). This makes it the spider with the largest leg span in the world. The longest leg span ever recorded on a Goliath bird-eating spider was 12.6 inches (32 cm) across. To put that into perspective, a dinner plate is typically 10-12 inches in diameter, so these spiders can be as wide as a plate!
Most tarantulas have a leg span between 4-6 inches. So the Goliath bird-eating spider dwarfs even its closest tarantula relatives in terms of sheer size. When walking, the Goliath spider’s legs extend even farther than 12 inches as they stretch out to take each step. The massive leg span allows them to cover ground quickly as they hunt for prey.
Body Size
In addition to leg span, the Goliath bird-eating spider also has a very large body size. The body of a Goliath spider can reach up to 2.4 inches (6 cm) in length.
Some key body size statistics for the Goliath bird-eating spider include:
- Body length: Up to 2.4 inches (6 cm)
- Cephalothorax (head area) width: Up to 2.2 inches (5.5 cm)
- Abdomen width: Up to 2.2 inches (5.5 cm)
So these spiders essentially have bodies the size of a human fist or even larger! The cephalothorax (head area) and abdomen can both span over 2 inches wide when the spider is well-fed.
Compared to other tarantulas which usually have body lengths between 1-2 inches, the Goliath really stands out in terms of its overall body mass and size. It’s no wonder it earned the name “bird-eating spider.” This species dwarfs nearly all other spiders on Earth!
Weight
The massive size of the Goliath bird-eating spider also translates into a very hefty weight. These spiders can weigh up to 6 oz (170 g).
To put that into perspective, 6 oz is:
- Over 3x heavier than other large tarantulas (which weigh around 1.5-2 oz)
- Around the weight of a small banana
- Close to the weight of a computer mouse
The heaviest Goliath bird-eating spider on record reportedly weighed 6.2 oz (175 g). At maximum weight, these spiders are truly giant, heavy creatures relative to most other spiders. The combination of the leg span, body size, and weight makes the Goliath one of the largest arachnids on the planet. They put other large spiders like the huntsman and wolf spider to shame in terms of total mass.
Fangs and Mouthparts
In keeping with its large size, the Goliath bird-eating spider has very prominent fangs and mouthparts.
Some key facts about the spider’s fangs:
- Fang length – up to 1 inch (2.5 cm)
- Fang arrangement – two large front fangs surrounded by smaller secondary fangs
- Venom – relatively low potency for humans, but still painful
The two front fangs can each reach an inch in length and are used to quickly strike prey and inject venom. The secondary smaller fangs surrounding the front fangs are used to hold prey and move food into the mouth.
In terms of size, the Goliath’s fangs rival those of some venomous snakes! Only the largest species of tarantulas from South America and Asia have comparable fangs. The Goliath uses its sizeable fangs to take down insects, frogs, rodents, and even small reptiles and mammals it may encounter while foraging across the forest floor.
In addition to the sizable fangs, the Goliath spider has a set of large mouthparts used for ingesting food. Once prey is paralyzed or killed by the venomous bite, these mouthparts are used to rip the prey into pieces and move the food into the spider’s digestive system.
So in summary, the fangs and mouthparts scale proportionally with the Goliath’s overall size, making them the largest of any spider species in the world.
Size Comparison to Other Animals
It’s useful to compare the Goliath bird-eating spider’s size to some common animals to really understand its massive scale.
Compared to a mouse:
- Mouse length: 3-4 inches
- Goliath leg span: Over 3x longer at 12 inches!
The mouse looks tiny compared to the giant spider.
Compared to a small rat:
- Rat length: Around 9 inches
- Goliath leg span: Wider at 12 inches
The rat is dwarfed by the spider’s legspan.
Compared to a guinea pig:
- Guinea pig length: Up to 9 inches
- Goliath body length: Around 2.5x shorter at 3.5 inches
The guinea pig is much longer, but the spider is wider.
Compared to a kitten:
- Kitten length: Around 14 inches
- Goliath leg span: Kitten is slightly longer
The spider and kitten are close in size, with the kitten a bit longer in length.
So while the Goliath spider can’t quite compare to the size of a small puppy or larger animals, it approaches the size of some common household pets. The spider is smaller in linear length but its thick legs and wide body make it wider than many mammals. Overall, it ranks among the largest invertebrates on Earth in terms of total size.
Habitat and Behavior
The Goliath bird-eating spider inhabits humid tropical forests in northern South America.
Key facts about its habitat:
- Found in rainforests and swampy regions
- Lives in deep burrows up to 6 feet deep
- Nocturnal – spends days in burrows and emerges at night to hunt
- Lives solitary – does not share burrows with other spiders
These spiders construct large, silk-lined burrows with a removable top layer of leaves and soil for camouflage. Their burrows provide a humid environment and protection from predators.
The solitary Goliath spider patiently waits near the entrance of its burrow at night to ambush passing prey. Its immense size allows it to take down a wide variety of small animals.
Reproduction involves the male leaving its burrow in search of a female’s burrow. Once mated, the female lays an egg sac containing up to 200 eggs. Spiderlings hatch in 6-8 weeks and are cared for by the female for a short period before leaving to make their own burrows.
So in summary, the Goliath thrives in the humid tropical forests of South America thanks to its large size and speed which allows it to effectively hunt in that environment. It leads a solitary, burrowing lifestyle emerging only at night to find food.
Population and Conservation
The Goliath bird-eating spider has a fairly limited range in northern South America. It is found mainly in:
- Venezuela
- The Guianas (Guyana, Suriname, French Guiana)
- Parts of Brazil
- Possibly Colombia
Within this range, the spiders are locally common in tropical lowland forests near streams and swamps. But their overall global population is declining due to habitat loss. Some key threats this species faces:
- Deforestation and land development
- Logging and agricultural activities
- Climate change – drying out of rainforests
Due to declining numbers, the Goliath bird-eating spider is classified as Vulnerable on the IUCN Red List. Trade and collection are also minor threats to this species.
Some conservation actions that could help protect Goliath spider populations include:
- Habitat protection – preventing deforestation of tropical lowland rainforests
- Land management practices that maintain humidity and soil conditions needed for their burrows
- Restrictions on commercial collection and trade
With focused conservation efforts, the magnificent Goliath spider may continue inhabiting South American rainforests as one of the largest invertebrate predators of its ecosystem.
Goliath Spiders in Captivity
Goliath bird-eating spiders are sometimes kept as pets by exotic animal collectors and arachnid enthusiasts. Though large, these spiders are usually not aggressive when properly handled and cared for.
Here are some key considerations for keeping Goliath spiders in captivity:
- Require a very large habitat – minimum of 20 gallon tank but larger is better
- Need deep substrate to burrow – at least 6 inches of peat moss or potting soil
- Require tropical conditions – warm temperatures around 80°F and high humidity around 80%
- Live up to 15 years with proper care
- Docile temperament – can be handled gently if accustomed to it
- Will readily eat crickets, roaches and other prey just slightly smaller than themselves
Overall, caring for a giant Goliath spider is an intense undertaking, but can be very rewarding for dedicated enthusiasts seeking a docile giant spider. Exotic pet laws should always be checked since these spiders may be restricted in some areas. With good husbandry, these spiders can live over a decade and grow to become a beloved pet.
Key Facts Summary
To summarize key facts covered about the Goliath bird-eating spider:
- Largest spider in the world by mass and size
- Legspan reaches 12 inches (30 cm)
- Body length up to 2.5 inches (6 cm)
- Can weigh up to 6 oz (170 g)
- Native to northern South America
- Inhabits lowland tropical rainforests
- Lives in silk-lined burrows up to 6 feet deep
- Nocturnal hunter that eats small vertebrates and inverts
- Classified as Vulnerable due to habitat loss
The Goliath bird-eating spider’s giant size makes it a formidable predator and the largest known spider by mass. Though potentially alarming due to their size, these spiders are not inherently dangerous to humans and are valued by exotic animal keepers. With conservation of their delicate rainforest habitats, these iconic giants of the spider world may continue thriving in South America.
Frequently Asked Questions
Here are answers to some frequently asked questions about the Goliath bird-eating spider:
How much venom does a Goliath spider have?
Goliath spiders have a relatively small amount of venom compared to other spiders. Their venom is not very potent and is designed to take down small prey rather than large animals or humans. The volume of venom is only around 0.18 mg.
What is their lifespan?
Goliath bird-eating spiders generally live between 10-15 years in the wild. Some reports indicate they may live over 20 years in captivity. Females tend to live longer than males.
How fast can they move?
These large spiders can move surprisingly fast at speeds over 1 foot per second when hunting. Their top speed is estimated at around 3-4 feet per second over short bursts.
Are Goliath spiders dangerous to humans?
While they do possess venomous fangs, Goliath spiders are not considered seriously dangerous to humans. Their venom is comparable to a bee or wasp sting in potency. However, because of their large fangs, their bites can cause slightly more pain and larger puncture wounds.
Where are Goliath spiders native to?
This species is native to northern regions of South America including Venezuela, the Guianas, Brazil, and possibly Colombia. They inhabit tropical rainforests and swamps.
How do they reproduce?
Males leave their burrows in search of female burrows. After mating, the female lays up to 200 eggs in an egg sac. Spiderlings hatch after 6-8 weeks and leave the burrow once they are large enough.
What eats Goliath bird-eating spiders?
Large lizards, snakes, frogs, toads, mice, rats, and small mammals may prey upon Goliath spiders, especially younger juveniles. Birds and their eggs can also be eaten by the spiders.
Conclusion
In conclusion, the Goliath bird-eating spider is the undisputed heavyweight champion of the spider world. With massive legs spanning over a foot and weight approaching 6 oz, these giants can take down small vertebrates with their sizeable venomous fangs. No other spider approaches the total body size and mass of a large Goliath. These solitary rainforest dwellers are increasingly vulnerable due to habitat loss and face an uncertain future. Responsible exotic pet keepers have also developed a fondness for Goliath spiders due to their docile nature. While frightening in appearance, their intimidating size is a sign of the spider’s evolutionary success in the tropical forests of South America where it continues to thrive as an apex invertebrate predator. The Goliath spider’s unmatched size secures its legacy as one of the most spectacular arachnids on the planet.
