Crab

• Crab burrow on the sides of the bunds and live.
  
• They cut the young paddy plants near the ground level and carry them to their burrows for feeding.
• They are active during night; as they are nocturnal.
• Besides their crop damaging activity, they prepare a series of burrow in the paddy
• Fields due to which water is not retained in the field.
• Thus,crab is major crustacean pest of paddy crop, it requires intensive control.

Eggs: The eggs are bright orange when first deposited, but become yellow, brown, and then dark  brown before hatching.

Larvae: First stage larvae, called zoeae, measure approximately 0.25 mm wide at hatching; development to this stage requires 31-49 days.

Juveniles: The juvenile "first crab" is typically 2.5 mm wide (from tip to tip of the lateral spines of the carapace). Juveniles gradual1y migrate in to shallower, less-saline waters in upper estuaries and rivers, where they grow and mature

Adult: Sexual maturity is reached after 18-20 post larval molts, a t the age of 1-1.5 years. Males   continue to molt and grow after they reach sexual maturity, but females cease to molt and grow when they mature and mate.

• Application of FYM at the time of puddling reduces crab damage.
• Block the mud holes on the farm bunds and mix paste of Silk Cotton (Bombax ceiba) tree bark, Embelia ribes fruits and Asafoeitda 2 kg each in 100 lit water in 1 ha.
• Crab burrows fumigated with the cyanogas dust.
• Poison baiting of 0.5% parathion with rice syrup at the rate of 80-100 ml per burrow is quite effective is controlling the crabs.