Though relatively new in the aquarium hobby, vampire crabs have made a splash. They’re semi-terrestrial, nocturnal mini crabs known for their bright yellow eyes and vibrant colors. If you’re looking for a new challenge, breeding these beautiful crabs might be something to consider.
Not only are vampire crabs relatively easy to care for—with the right tank setup, of course—but they also breed readily in captivity. With several color morphs to choose from, you can quickly go from having a few crabs to having a tank full of these beautiful crustaceans.
In this guide, you’ll learn the basics about vampire crabs and how to breed them in captivity.
Species Snapshot
- Species Name: Geosesarma sp.
- Common Names: Vampire crab
- Size: Up to 2 inches
- Lifespan: Up to 2 years
- Native Distribution: Southeast Asia
While there are over 50 recognized species in the Geosesarma genus, there are only a few species of vampire crab that have become readily available to hobbyists.
The species often simply called the vampire crab (Geosesarma dennerle) exhibits an intense purple coloration with patches of yellow or cream color on its back and bright yellow eyes. The red devil vampire crab (Geosesarma hagen) is reddish-brown with bright red claws and red-orange coloring on its back.
Vampire crabs remain small, growing to a maximum size of 2 inches including their leg span. These crabs have ten legs, two of which end in claws. The claws are capable of pincer action but because they’re so small and they don’t open very much, they don’t pose much of a pinching hazard to humans.
Sexing Vampire Crabs
Breeding vampire crabs is relatively easy and doesn’t require much specific preparation beyond an appropriate tank environment. The key to maintaining a successful colony is starting with an ideal ratio of male to female crabs. It’s also wise to ensure your tank is large enough with adequate décor (primarily plants) to give your crabs places to hide.
The best ratio for breeding vampire crabs is one male for every two females. You can keep a group of three vampire crabs in a tank as small as 5 gallons, but a larger tank is preferred for breeding purposes.
Because vampire crabs are sexually dimorphic, it’s simple to tell the difference between males and females. Male vampire crabs tend to be a little larger than females with more prominent abdomens. The most obvious difference, however, is claw size—males have bigger claws.
Setting Up a Breeding Tank
You don’t necessarily need to set up a separate tank to breed your vampire crabs—they’ll breed readily when the conditions are optimal. The eggs are vulnerable to adult crabs, however, so you might consider keeping a separate enclosure for the females to lay their eggs in.
Vampire crabs require an environment that includes both land and water, ideally a ratio of 80% land to 20% water. The land portion should be decorated with soft substrate and plenty of plants of varying heights while the water should have a sandy substrate and be kept clean. You can also add aquatic plants to the water portion of the tank.
Maintaining high humidity levels is essential for keeping your vampire crabs healthy, particularly for successful breeding. Vampire crabs breed during the rainy season, so make sure your tank is equipped with a humidifier to maintain a minimum humidity level of 75%. You may also be able to maintain this humidity level by misting the tank daily.
Second to humidity, substrate is the most important factor for successful breeding. A soft substrate like coconut fiber or sphagnum moss helps retain moisture but also provides a surface to keep the eggs safe from adult crabs in the tank. Avoid using a substrate that compacts so much that your crabs won’t be able to burrow into it easily.
Breeding Vampire Crabs
While there is no established breeding protocol for vampire crabs, this species appears to breed readily in captivity. As long as you provide the right substrate and ideal tank conditions, your vampire crabs should breed without much provocation. It may help to condition them with a varied diet of nutrient-rich foods including crab or shrimp pellets, blanched vegetables, and live or frozen foods.
Vampire crabs become sexually mature around six months of age. When your crabs are ready to breed, the females will deposit their eggs in the substrate and the males will then come along and fertilize the eggs. From there, the female gathers up the eggs and carries them around for about a month until they hatch.
Unlike some crab species, vampire crabs do not appear to go through a larval stage. When the eggs hatch, they are fully formed miniatures of adult crabs. Because they are so small—only 1-2mm long—the female crab carries them under her abdomen for another few weeks while their exoskeletons harden. A female vampire crab can carry anywhere from 20 to 80 eggs at a time.
Raising Baby Vampire Crabs
Caring for baby vampire crabs is no different from caring for adults. It may be wise to remove adult crabs from the tank until the babies are too large to be eaten, but they don’t require any special care. The most important thing is to provide them with soft substrate to burrow into and other places to hide throughout the tank.
You can feed baby vampire crabs the same food you’d offer adults. It’s wise to provide a variety of foods to make sure the crabs get all the nutrients they need. Calcium is particularly important because the baby crabs will molt frequently during the first six months of life. A nutritionally balanced crab or shrimp pellet should be adequate to meet the crabs’ calcium needs.
As your baby vampire crabs grow, consider when it may be appropriate to separate some of them into another tank. When the males mature, they may begin to fight the existing adults for territory and the breeding process will continue. If you’re selectively breeding for color or pattern, culling less desirable specimens may become necessary.
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