Crayfish
How can you Identify a Crayfish?
There are many differnt types of species of Crayfish worldwide with differnt colors, sizes and appearance. Each Crayfish is differnt in their own way, some of the crayfish living in the freshwater you can identify by looking for certain things listed below.
Identification of some of the freshwater Crayfishes:
"Gilgie"- No spines on the telson. Two pairs of small spines on the rostrum.
"Margaret River Hairy Marron"- Middle keel extends all the way to the cervical groove. Head covered with short hairs.
"Smooth Maroon" - Middle keel does not extend to the cervical groove. No hairs on the head.
"Koonac"- Chelipeds (claws) are oval in shape and quite broad.
"Yabby"- Chelipeds (claws) are quite large. There are hairs on the inside of the ‘elbow’.
There are many differnt types of species of Crayfish worldwide. If the water is the exact same from another countries water that doesnt mean that the Crayfish appears the same way, each country and every differnt river, damp etc. is differnt.
Endangered:
There are over 500 differnt species of Crayfish worldwide and many of them are endangered. Some are:
The Big Sandy crayfish
Guyandotte River crayfish
The Oklahoma Cave Crayfish
White-clawed Crayfish
Atlantic Stream Crayfish
River Crayfish
Shasta crayfish
These Crayfishes are endangered due to overfishing and other animals taking over thir terriotory.
Polloution
Because they are numerous types of crayfish some species react differently to different types of pollutions. This varies in each body of water as they maybe too much sodium, calcium, or even chloride in the water. An experiment done in Ontario with the pH and varying aluminum concentration and hardness, showed that it was toxic to juvenile but not to females carrying babies in the Orconectes rusticus(Rusty crayfish) and O. propinquus species. (Rusty crayfish clearwater type).