Hermit crabs are fascinating creatures that have a unique reproductive process. In this article I’ll explain in simple terms how hermit crabs mate and reproduce.
An Overview of the Hermit Crab Life Cycle
The hermit crab life cycle begins when a male and female mate. The female then carries the fertilized eggs on her abdomen until they are ready to hatch. Once hatched, the tiny larvae go through several stages before becoming juvenile crabs. After maturing, the juveniles find a shell and become the hermit crabs we know and love!
Here is a quick rundown of the hermit crab life cycle
- Mating – A male and female mate, allowing the female to produce a clutch of eggs.
- Egg incubation – The female carries the eggs on her abdomen for 3-4 weeks until they are ready to hatch.
- Larval stages – The eggs hatch into tiny free-swimming larvae that go through several stages over 6-8 weeks.
- Settlement – The megalopa larvae find shells and settle down, becoming juvenile crabs.
- Maturation – Over 2-3 years, the juvenile crab eats, grows, and molts into an adult hermit crab.
- Reproduction – Adult males and females mate and produce eggs, starting the cycle again.
Now let’s look at each stage of the life cycle in more detail.
Mating Between Male and Female Hermit Crabs
Mating can occur year-round but typically peaks in spring and summer. To mate, the male uses his modified abdominal legs to transfer sperm packets to the female’s gonopores.
The gonopores are small openings on the underside of the female’s abdomen where she receives the sperm. After a successful mating, the female uses the stored sperm to fertilize her eggs as they mature.
Interestingly, hermit crabs may mate multiple times with different partners throughout their lives. The female can store sperm for up to 18 months before using it to fertilize her eggs.
Egg Development and Hatching
About 2-4 weeks after mating, the female releases her fertilized eggs and attaches them to the tiny hair-like appendages under her abdomen. She may lay between 100 to 500 eggs at a time.
The female carries the egg mass or “clutch” under her body for 3-4 weeks as the eggs develop. She protects and aerates the eggs by fanning them with her small abdominal appendages.
When the eggs are ready to hatch, the female releases them into the ocean. There, the buoyant eggs hatch within minutes into tiny free-swimming larvae.
The Larval Stages of Hermit Crab Development
Hermit crab larvae go through several stages as they grow and develop in the ocean. The length of these stages depends on water temperature and other environmental factors.
Here are the larval stages:
-
Nauplius – The earliest larval stage lasts about 2 days. The larvae use their antennae to feed on algae and other plankton.
-
Protozoea – In this stage lasting 1-2 weeks, lateral spines and eyes develop but the larvae still swim and feed like nauplii.
-
Zoea – Over the next 2-4 weeks, the larvae develop primitive mouthparts and claw-like appendages. They actively feed on algae and plankton.
-
Megalopa – This final semi-benthic stage lasts 1-2 weeks. The larvae look and act much like tiny juvenile crabs.
After 6 to 8 weeks of larval development, the megalopa seek out empty snail shells to make their homes, becoming juvenile hermit crabs.
Metamorphosis into Juvenile and Adult Hermit Crabs
The megalopa larvae metamorphose into tiny juvenile crabs when they find a suitable empty snail shell and settle into it. This is a critical stage in the life cycle.
Juvenile crabs hide in their salvaged shells for protection as they eat and grow over the next 2-3 years into fully mature adults. They frequently trade up into larger shells as they grow.
Once mature, the crabs find mates – usually through chemical scent cues. After mating, adult females carry new clutches of eggs and the reproductive life cycle begins anew.
In captivity, hermit crabs may live over 10 years. But in the wild, most survive for only 3-5 years before succumbing to predators, environmental dangers, or the rigors of reproduction.
Fascinating Features of Hermit Crab Reproduction
Hermit crab reproduction involves some cool adaptations and unique behaviors:
-
Females can store male’s sperm for months before using it to fertilize eggs.
-
Females carry and aerate the eggs until ready to hatch.
-
Larvae go through a complex series of developmental stages.
-
Megalopa larvae must find a suitable empty shell to survive into adulthood.
-
Juveniles hide in salvaged shells for protection during growth and maturity.
-
Adults frequently trade up into ever-larger shells as they grow.
Captive Breeding Hermit Crabs || Spawn Day | By Crab Central Station
How do hermit crabs reproduce?
This means that they must breed to reproduce. Breeding requires one male hermit crab and one female hermit crab. The male mates with the female to fertilize the female’s eggs. The female takes the fertilized eggs and holds onto them. These eggs are kept in the shell for quite some time as they continue to get closer to hatching.
Are female hermit crabs receptive to breeding?
In their life cycle, female hermit crabs are most receptive to breeding when they’ve just finished molting. Keep an eye out for signs of molting so you can start preparing your breeding tank during the process. Wait until the female hermit crab is back to normal before introducing her to the breeding tank.
Do hermit crabs lay eggs?
Hermit crabs do indeed lay eggs. Female hermit crabs lay eggs in the ocean. After mating with a male hermit crab, the female crab will have its eggs fertilized. It’ll then keep the eggs in its shell for a while. Earlier, you learned that the female places the eggs in the water. This is true, but it doesn’t happen right away.
How do hermit crabs mate?
Female hermit crabs release pheromones to attract males, and mating often involves a complex courtship ritual. Once fertilized, the female carries the eggs on her abdomen until they hatch into larvae. The larvae then spend several weeks in the ocean before settling on the ocean floor and developing into juvenile hermit crabs.