Blue Crab Life Cycle

Egg

After mating, the female crab migrates to the salty waters of the lower bay where her eggs develop into an orange mass containing an average of 2 million eggs. Only a small fraction of her eggs will develop into adult crabs.

Threats to population:

• Illegal fishing of female crabs carrying eggs

• Predators such as small fish and jellyfish

Zoea

After about two weeks, larvae called zoea develops inside the egg mass and hatches near the mouth of the Bay, the area where the Bay meets the Atlantic ocean.  For about 45 days, the zoea float in and out of the mouth of the Bay, eating and molting (shedding its shells) about seven times as it grows.

Threats to population:

• Habitat loss due to warming waters, irregular weather, and pollution

• Predators such as eel, drum, spot, Atlantic croaker, striped bass (rockfish), and catfish

Megalopa

The zoea develops into megalopa and drifts into the more northern parts of the Bay, settling in underwater grasses, where it continues to grow.

Threats to population:

• Habitat loss due to warming waters, irregular weather, and pollution

• Predators such as eel, drum, spot, Atlantic croaker, striped bass (rockfish), and catfish

Juvenile crab

After the megalopa sheds its first skin, it transforms into a juvenile crab, now able to walk or swim on the bottom of the Bay. After molting 16-20 times, it becomes an adult crab.

Threats to population:

• Overfishing

• Water pollution

• Habitat loss

• Predators such as adult crabs

Adult crab

It takes about 12-18 months for a crab to become an adult. Once a crab has reached this stage it is ready to mate and continue the life cycle.

Threats to population:

• Extreme temperatures

• Overfishing

• Water Pollution

• Habitat loss

• Predators such as sharks, cownose rays, and sea turtles