Difference Between Blue Crab and Red Crab

Blue Crab vs Red Crab

Crabs become important in many ways, but their importance is known widely as a delicious food for humans, yet the ecological roles that they play is also of great value to the nature. Different crab species are of different importance, where blue and red crabs have not been a difference to that rule. Blue crab and red crab exhibit a range of differences with regard to physical features, behavioural characteristics, ecology, food values for human, and few other aspects.

Blue Crab

Blue crab is scientifically known asCallinectes sapidus，但名称Chesapeake Blue Crab，Atlantic Blue Crab也在使用。正如它的一个通用名称所暗示的那样，蓝蟹在大西洋中本地发现，但特别生活在大西洋沿海水域的西边缘附近。这些螃蟹具有美丽的蓝色附属物，带有黑色蓝色甲壳。甲壳的尺寸约为230毫米，并带有四个额牙，这是大西洋其他相关蟹物种的识别特征。他们表现出明显的性二态性，最突出的是腹部形状，在男性中苗条且长长，而女性则具有圆形和圆顶形的腹部。

Blue crabs are popular as a food for people, especially around Chesapeake city on the east coast of Virginia, United States and in the Gulf of Mexico. Blue crabs are omnivorous; they clean the sea by feeding on decaying matter of animals, but their preference to eat shelled bivalves and small fish should also be noted. It is fascinating to know that one female blue crab can produce an enormous number of eggs such as more than 8,000,000 in a lifetime.

Red Crab

红蟹最普遍地称为圣诞岛红蟹，其科学名称是Gecarcoidea natalis. Red crab is only found in the Christmas Island and the Cocos Island of the Indian Ocean. They have bright red appendages with a dark red carapace that measures about 11 centimetres. The carapace is round shaped with no serrated margins or frontal teeth. Their bright red appendages are large for the small carapace, yet the claws are small. Male red crabs are usually larger than the females, but the feminine abdomen is broader than the masculine one is. However, the difference between the male and female abdomens is valid for the adult (more than three years old) red crabs.

红蟹生活在洞穴中，以确保太阳不会将它们弄干。它们通过ill呼吸，主要以植物物质（例如叶子和花朵）为食。但是，红蟹有时也会以某些动物的物质为食。已经观察到红螃蟹的蚕食行为。红蟹的众所周知行为之一是每年向海洋迁移繁殖。数以百万计的螃蟹沿着海底迁移并产卵。根据估计的人口规模，应大约有4,370万红蟹，这是由于侵入性蚂蚁物种（黄色的疯狂蚂蚁）造成的大量人口减少，杀死了近三分之一的红蟹种群。

青蟹和之间的区别是什么Red Crab?

• As their names depict, blue crab and red crab are different in colours.

• Red crab is native to the Atlantic Ocean while blue crab is endemic to the Cocos Island and Christmas Island in the Indian Ocean.

• Blue crab is larger than the red crab.

•蓝蟹有锯齿状的甲壳，而红蟹有圆形的甲壳。

•与身体相比，附属物更大，而与身体相比，蓝蟹的腿较小。

• Blue crab is popular as seafood but not the red crab.

• Blue crab is an omnivore, whereas red crab is predominantly a herbivore but occasionally feed on animal matter.