Thursday, March 15, 2012
Crayfish with Babies
I crossed the path of about 10 crayfish on my morning hike and discovered every single one of them had babies on board. Every size from 3 inches long to 6 inches all were mothers. How these little guys hang on is a wonder! A fascinating morning...
Reproduction: Males and females, spurred on by messages communicated to each other, join periodically for mating, especially in the spring. Males can be told from females by the generally larger pincers and narrower tails, but these characteristics are not absolute. To tell for sure, you must pick them up and look underneath. Males have two pairs of modified swimmerets (the small leglike appendages under the tail) that are white-tipped and lay between the last pair of walking legs. The females have longer, softer-looking swimmerets (for holding the eggs) and a little white pore centered between the walking legs. Some time after mating the female lays about 200 eggs, which she carries in a mass under her tail.
After several weeks the eggs hatch, and a hoard of minute, perfectly formed, ravenous baby crayfish emerge. At first they continue to ride along under the female's tail, eating tiny waterborne bits of food, but soon they leave this security and head out on their own. During these early days many are eaten by fish, insects, and other crayfish, but some always survive to fulfill their destiny.
(No crayfish was harmed, only gently turned and then turned back.)