Crayfish Behavior

925 Words 4 Pages
Crayfish are freshwater crustaceans that use their claws called chelipeds,for warning off predators. When frightened, these crayfish lift their chelipeds to make threatening gestures, all while moving backwards or staying still. We examined how long it would take for crayfish to calm down once removed from the water and if the temperature had any influence to this observation. To do this, we placed two crayfishes in room temperature water and another two in colder water for an interval of five minutes and again for ten minutes. Once the time was up,we measured how long it took for the crayfish to lower their claws. By lowering their claws it represented them being calm. The results were mixed indicating that the temperature of the water, might …show more content…
No matter if on land or water, however we wanted to see if there was a certain factor that would change the animal 's behavior, especially for those that can survive on both land and water. The crayfish exhibits habituation, dishabituation,stimulus generalization and spontaneous recovery as its defense reflex, when stimulated with rapidly approaching targets (Glantz, R.,1974). Small crayfish compared to larger crayfish respond more dramatically when encountered with a predator (Stein, R. A., & Magnuson, J. J. ,1976). Males spend more time in an aggressive behavior than females (Stein, R. A., & Magnuson, J. J. ,1976). Many factors can be considered but in this experiment we tested for the temperature of water to see if it would affect how long it will take the crustaceans to be comfortable. If the water is at room temperature then the crayfish’s behavior will be calmer. Since room temperature tends to be fine for most animals and is at the middle of warm and colder temperatures we believed the crayfish would be at a tranquil state of …show more content…
Instead a crayfish in cold water and a crayfish in room temperature were both calm the moment they were taken out of water, while the other two crayfish took their time with getting comfortable. Although the crayfish exhibits habituation, dishabituation,stimulus generalization and spontaneous recovery as its defense reflex, when stimulated with rapidly approaching targets (Glantz, R.,1974), it did not truly show if temperature had any significance to its behavior. These results tell me that temperature could have possibly not have any effect, however it does bring several other factors to the light. Some things that we missed while selecting the crayfish was gender, age and size. With the factor of size, being missed during this experiment, other researchers have found that size is directly related to behavior in both genders. At an early age crayfish develop an aggressive behavior (Bovbjerg, R. V. ,1956). As stated in the the introduction, larger crayfish react very little if at all. Larger adults are also less affected by predators ( Stein, R. A., & Magnuson, J. J. ,1976). Another thing that we also failed to see, is if their level of activity indicates if they were truly comfortable, instead of them just lowering their claws. Crayfish raise their chelipeds and fully spread their chelae in response to a predatory threat. Even with threat still in their field

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