Transcript:

Today on Animal Fact Files we’re talking about vampire crabs. We talk about lots of other animals, so don’t be crabby - be sure to subscribe! These crabs don’t get their common name from their eating habits but from their bright yellow eyes. I mean, they do look a bit menacing, at least until you realize how teeny they are. There are somewhere around fifty vampire crab species and even more awaiting discovery and proper classification. Currently vampire crabs are all grouped in the same genus, but further research may change this. What’s funny about these crabs is that some species were kept as pets before they were even named by scientists. Though it’s not required, it’s generally considered a faux pas to name an animal without knowing the location from which it hails. While some species of vampire crabs had made their way around the world into the terrariums of pet owners, scientists didn’t actually knew where they came from. Nowadays, that isn’t the case. Vampire crabs all seem to originate from southeast Asia as well as the islands of the Indo-Pacific. They’re freshwater crabs which means they don’t traverse marine environments and thus may be separated into many pockets of different species among these islands. This could be bad news for hopeful pet owners of vampire crabs because they are likely found in limited groups in isolated locations, but captive breeding efforts are cropping up to help secure the survival of these crabs in the wild by providing captive bred animals for the pet trade.

Vampire crabs live in a variety of habitats. Some live in waterways such as creeks and flooded forests. Others dig burrows near streams. These burrows will fill with water and may be used for breeding purposes which we’ll be discussing later. There are different species who may have almost abandoned water completely and live in damp forests under logs and rocks far away from a permanent water source. This might not seem like a big deal, but it’s actually kind of weird for crabs. We’ve talked about nearly terrestrial coconut crabs previously, but even they require water as part of their life cycle. That may not be the case with all vampire crab species.

It’s thought vampire crabs come in flashy colors in order to attract mates. Most vampire crabs species produce small amounts of large eggs. Okay, well, a one millimeter diameter egg might not seem that large, but that’s on the small end, some of their eggs can double that size. And considering vampire crabs are usually less than an inch wide (2.54 centimeters), one millimeter is almost four percent of their body length. These relatively large eggs could suggest that the baby vampire crabs completely develop inside their eggs. These babies are then carried by the female for upwards of a week before they set off on their own. There are, however, other species, like the ones who dig the burrows near streams, who may produce smaller eggs that hatch inside the water in the burrows away from the currents of the stream and live there as larvae that quickly develop into their adult form. These different development strategies are part of the reasoning behind why scientists think these crabs might need some classification changes.

Wherever they live, and however they reproduce, vampire crabs are all pretty freaking tiny. As such, they’re probably food for many predators, including birds, small mammals, and even fish for the more aquatic species. How long they can live in the wild is currently undocumented, but in captivity they’re reported to live to be three years old. Vampire crabs are omnivores and eat practically anything, which is admittedly a little less exciting than what their common name might otherwise imply - but they typically do this at night which is quite vampirish if you ask us!

For more facts on vampire crabs, check out the links in the description. Give a thumbs up if you learned something new today, and thank you for watching Animal Fact Files.