Do crayfish attack each other, if so, why?  Dietary or aggressive reasons?
108098
BioGeeks got it goin on!
241627
usually, they eat each other. Have you ever heard that "the big fish eats the small one"? Also, they can eat plancton, or algae... there are plenty of food (organic material) floating around in the ocean.
244990
I work at a pet store and we sell tarantulas we feed them one cricket a day.make shure not to put to many cricket in with the spider because they can eat the spider.
861630
VERY rarely reticulated pythons have been known to attack and eat people in their native environment.... But it is a VERY rare occurance.\n\nOther than that, yes.  Snakes only bite when threatened.  Their first line of defense is their camoflauge, then they will try to escape.  If they are cornered many will hiss, puff up, hood, rattle etc... to try to scare you away.  They generally only bite as a last resort or if restrained/stepped on.  Many venomous species can even give "dry bites" where no venom is injected.
677812
I've heard of attacks by mockingbirds and bluejays and have seen both of these birds swoop on other potential predators such as cats. They only do it when they feel their nest (with eggs or nestlings) is threatened. The solution is just to stay away from the nest.
964845
wow...  it might be easier to list the animals that don't. When you add in fresh-water crustaceans, you get even more mamals and such. In fact, between zooplankton and shrimp alone, probably 90% of the aquatic population eat crustaceans, from simple hydra all the way up to baleen whales.
19922
Fish eat other fish. Bigger ones eat smaller ones. In the case of a whale, notice its strainer type mouth? They take in large quantities of Crill which are very small shrimp. Others feed by sucking plankton or moss off rocks (thus cleaning). Others by snatching flying or swimming bugs off the surface.
599686
Female anacondas do not devour the males!\n\n- Praying mantis\n- Many spiders\n- Ceratopogonid midges\n\nhttp://www.yesbutnobutyes.com/archives/ugly_animal_kingdom/index.html\n\n---------\nUpdate: An interesting article that discusses adaptive and nonadaptive hypotheses for sexual cannibalism in spiders.  The evidence suggests that, at least in spiders, there's a connection between foraging decisions and cannibalistic behaviour towards males. \nhttp://www.blackwell-synergy.com/links/doi/10.1046/j.1420-9101.2002.00363.x/full/\n(let me know if you cannot download the article)
86909
A difficult question.\nThe two references below have something to say about whether or not fish feel pain. The arguement claiming 'Yes' is related to the evolution of survival behaviours and hard to refute. It does however hold true for any animal which responds negatively to stimuli.\nIt is certainly true that if you stick a pin into a maggot it will wriggle - it certainly does not like it. Fish are none too keen either.
345462
Yep.  Same thing as a crawdad too.  \n\nBut there's no such thing as a craydad.  Go figure.
54858
I think it is the bear. Most of the other animals do not attack unless they are hungry or provoked. But the bear has the unique distinction of attacking without any kind of provocation - just for the fun of it!
225807
Crabs run or move sideways because that is the way their legs bend. Crabs do not have ball-and-socket joints; many crabs have joints in their legs moving in a restricted number of planes so that they can only move sideways. Many crabs like the "Shore Crab" need to scamper sideways to avoid the legs getting tangled up with each other. \n\nMuscles work in pairs. A muscle can only retract, or pull; to lengthen again it must relax and be pulled back by another 'antagonistic' muscle. The muscle blocks in crabs are attached to the inner surface of the exoskeleton, including the ten tubular legs, including the legs with claws, or chelae, as well as other appendages.\nAslo,For animals, their body lengths are normally larger than the widths. For locomotion, animals usually move along the long axis of their bodies. As crabs run sideways, they are moving along the long axis of their bodies.\n\nCrabs are scavengers; they do not need to move forward in pursuit of preys like predators do.
616561
The scales- Same structure, shape, and composition- In fact, a related function, since sharks will brush the sides of their body by interesting possible food items to scrape off a little (of your skin, for example) in order to "taste" it with special sensors in the skin.  Generally, if a shark does this with a human, they will *not* attack further.
930544
Maggots, worms are good as the trout is very predatory. Also they will take bread flake, infact they love it. Its cheap and can be used with ease. A top bait, and it works at night, they can really smell it. For me, it would be bread then maggots then worms TIGHT LINES
257100
Crayfish, sometimes called crawfish, are freshwater crustaceans resembling small lobsters, to which they are closely related. They are found in bodies of fresh water that do not freeze to the bottom, and which have shelter against predators. Most crayfish cannot tolerate polluted water, although some species such as the invasive Procambarus clarkii are more hardy. Some crayfish have been found living as much as 3 m (10 feet) underground.\nThe study of crayfish is called astacology.\nThe anatomy of crayfish may be found in the article "Decapod anatomy
936589
Piranhas are triggered to attack by erratic behavior from the animal they wish to eat. If a catfish is missing a fin so it is swimming in an unusual way the piranha tear it to pieces. The same catfish with all its fins, healthy, swimming with confidence, has a much greater chance of not being eaten. His chances go from 0% to about 50%. Also blood in the water will set them into a frenzy. They prefer to attack the wounded, sick, and dying.\n\nAlso there are close to 100 species of piranha and only four known dangerous species. One of those four is called the Red Bellied Piranha. It is possible they were not swimming with this particularly nasty species but with one of over 90 more docile species.
881260
I guess its because they eat different things- shells are essentially made up of certain things that the animal eats. Also, I guess from an evolutionary point of view, an animal ends up with either hard or soft shells based on the environment within which they live. They would need a hard shell if they were living in difficult surroundings where damage would be easily possible. So its more complex than you'd think! Good luck!