If you find it impossible to imagine giant tarantulas in any type of friendly relationship with another creature, the Columbian Lesserblack tarantula is here to prove you wrong. This predatory spider shares its burrow with an unlikely companion: the tiny Dotted Humming frog.
To be fair, the frogs aren’t really pets (by our human definition). However, this unusual relationship is a fascinating example of the symbiosis that exists in nature. Though the amphibians could easily be a tasty snack for these giant jungle tarantulas, the two species have partnered in a mutually beneficial way.
In The Burrow Of Giant Tarantulas
This intriguing partnership was first documented in 1986. Two researchers, Reginald Cocroft and Keith Hambler, studied the spider and frog relationship in southeastern Peru. Citing other examples of similar frog species cohabitating with spiders, Cocroft and Hambler wanted to further examine the Columbian Lesserblack’s behavior.
During almost 3 months of observation and careful study, the scientists noted odd behavior. The giant tarantulas stayed in burrows, coming out around dusk to wait for prey at the entrance of their home. The Dotted Humming frog, a small nocturnal species, did the same–always emerging from the spider burrow unscathed.
Oddly enough, it wasn’t just a lack of harm that researchers noted. The frogs were often seen underneath the spiders, moving below and passed them without consequence. Often, the giant tarantulas simply shifted a leg or moved their bodies to allow the frogs to pass. On a few occasions where one of the younger spiders pounced on a frog as it left the burrow, the spider would release the frog after just a few seconds. (1)
Testing The Theory
Since the Dotted Humming frogs were never harmed by the spiders, researchers naturally tested the relationship. After 5 weeks of observation, a “feeding program” would further examine the special symbiosis. This test would include frogs from 6 other species, dropped at the burrows in front of the spiders. As a result, 7 out of 9 frogs were quickly consumed by the tarantulas. On the flip side, the spiders did not show the same predatory behavior towards the Dotted Humming frogs.
Other theories were introduced to further cement the relationship. Snakes that would normally prey on the frogs were pulled passed the burrow; the tarantulas attacked, essentially protecting the frogs inside. Sometimes the frogs would actually take refuge under the spider for protection. (1)
A Mutually Beneficial Relationship
Research clearly shows these species are unlikely friends, but why? It appears the answer is that both of these burrow dwellers benefit.
While the Dotted Humming frog’s skin might not be the tastiest to the tarantulas, both species clearly help each other. From Cocroft and Hambler’s research, it appears that the frog benefits by eating all the bugs attracted to the spider’s prey leftovers. The amphibians also receive safety from their large protector, with bigger predators blocked from entering the burrow. For the giant tarantula, the frog may keep their eggs safe. Microhylids like the Dotted Humming frog specialize in eating ants. One of the biggest predators of the Columbian Lesserblack’s eggs? Ants. It may be, then, that the frog keeps the eggs safe and the spider keeps the frog safe. (2)
Clearly, then, these two species are a lesson in working together. Despite vast differences, this tarantula and frog duo have found that ensuring each other’s safety is reason enough to share a living space. It appears that the tarantulas may see these tiny frogs as pets and friends, just like we do.
