Snails do have predator/prey killer instincts

[joyce tryoon]

Our snails do have predator/prey killer instincts. Some of us have observed this first hand. Others have never experienced this. The instinct is there. For those of us that have had the experience, I would like to talk a little about this, and in hopes you will too.

Many have beaten them selves up with guilt, wondering what they are doing wrong,heaping blame on themselves.

All animals need food and yes they will kill to eat. Once they do this and find that the food tastes good. Then they hone their hunting and killing skills. They never unlearn this behavior. Just put it aside, until needed, or they have the opportuinity and kill because they can.

Surplus Killing-
This does occur. The conditions are usually when prey is easily and plentiful and available to the predator or predators.
The prey cannot escape or is ignorant of how to do so.
Domesticated in an unnatural enviroment.
Therefore the predator can expend negligible energy in the hunt. Without risk or cost of injury of killing its prey.

Many animals are surplus killers( animals that kill just to kill, after they have eaten what they want)
fox,hyenas, wild dogs, mink, cats, and crows are some examples.
An example was used here. Marisa babies ate all the Cana babies. This usually happens over night. Babies eat a lot and this would be very easy for them in a few hours. I know of 3 instances of this happening now.

The main reason for killing and eating tank mates, is not from hunger but for the experience, sensation and to hone their skills.

Excess prey can over-stimulate the senses. This brings on predator behavior.

Learning instincts, honing reflexes and becoming skilled in your niche are extremely important functions for any animal.

Animals simply follow the pleasures of their stimulations and cease when interrupted by pain or fatigue.

Do we eat when we aren't hungry? Speaking for myself. I have eaten a whole box of that chocolate bridge mix. Just because I liked it and it gave me sooooo much pleasure.
Also love to pop bubble wrap. Its destructive but gives me such a good feeling of pleasure.

This bubble wrap thing is akin to a fox in a hen house with a bunch of flapping chickens.

What I want to get across is:
This is a natural instinct for our snails. Not our fault. Its the natural order of things. I sincerely hope you never have to see this. But if it has happened or does happen, please don't blame yourself.
I will post some of my experiences with this and hope you do too.
Joyce

[joyce tryoon]

Predator behavior I have seen in my snail tanks.
A large Cana pick a small Bridge up with its foot and bash it against the glass,
Killing it.

Cana picking a Bridge up and banging it on the floor of the tank, killing it.

Baby Cannas ganging up on one tankmate and eating it. Working togethor to do this.

Marsis eating baby Canas. I have never seen a Cana eat a Marsis.

Canas attacking a snail with a fissure with flesh exposed. The injured snail cannot close up to protect its self. The odd part is that the vulnurable snail can live in that tank for a month or two . Then all at once the Canas have it for dinner.
At all times when the killing happens there has been ample food in the tanks.
Most often the predators are young. Rarely have seen this in the older snails. Seems to stop at around six months.
These are just some of what I have seen.
Joyce

[angllady2]

I have had first hand experience with this phenomenon as well Joyce.

Back when I got my first Insualrum pair, I kept them in my big 30 gallon brig tank with no problems at all. I was so excited to get eggs from the pair!

It took several months of trying to get babies however, and by then I had set up a 20 gallon long for my baby brigs that were growing like weeds.

When the Insularum babies were big enough, about pea sized, I added them to the brig nursery tank. All went well for a few weeks, all the babies were happily growing side by side. Then, about the time the Insualrums hit dime size, I started noticing empty shells in the tank. A LOT of empty shells. This puzzled me, cause I watched that tank like a mother hen. I fed those babies ten times more than they could possibly eat of several different kinds of food. Algae discs, shrimp pellets, snail cookies, fresh veggies, you name it. I was doing water changes every other day to keep the water healthy from the amount of excess food and waste, and still every day there were more empty shells.

It took me almost a week to realize the shells were all brig shells. By now there were only a handful left. One night I was watching the tank while contemplating the problem I could not find, when I got to see the answer first hand.

A group of insularums, about 6 in all, were clumped together in one corner. This was not unusual, so I was only half paying attention. Suddenly, the group broke up and surrounded a nickle sized brig that wandered by. They completely covered the brig, turning it over and over and prying at it, at least that's what it looked like. I kept on watching, wondering what on earth they could be doing. After almost 30 minutes, they wore the brig down and pryed the operculum open, they then proceded to tear the brig from the shell and eat it. I was so shocked!

I kept on watching, and sure enough, there were four or five such "packs" ranging from 4 to 8 Insualrums and I watched them hunt and kill 4 brigs that night. Each time they did the same thing, pick out the victim, surround it, and take turns prying at the shell until they wore the vicitm down, at which time they tore it from it's shell and ate it. I removed the remaining dozen or so brigs that night.

All was quiet for about a week, then I started finding small empty Insuarums shells in the tank. Denied the ready source of pleasure from hunting brigs, they turned to hunting one another. Even seperating them into two tanks to reduce the number of snails in each tank did not help. The smaller and weaker snails were methodically hunted and eaten. I watched the bigger snails hunting with fresh food in the tank for them to eat. I truthfully think they enjoyed it.

At around 6 months of age, the behavior stopped, and I've never seen an adult do it. I think perhaps it has to do with survival instincts like you said. Kind of like in "White Fang" the law is EAT OR BE EATEN.

I've also raised cana babies who did this, although not in packs like insualrums do. My canas seemed more one on one hunting than in groups.

So, if you get into raising canas or insularums, be prepared for this to happen, as it is my opinion no matter how well cared for they are, they will do this.

Gale

[joyce tryoon]

Gale,
wooooo gal you can write. Felt like I was there
I remember this. How very upset you were. Your babies dieing
and no clue why. Then saw how they were dieing.

The lack of food has nothing to do with this behavior. I always feel so bad, when a new person happens on this. One snail munching on another.Some have been heartbroken to think their snail would do such a thing. Others get mad at the munchie. Wonder why they would do such an awful thing. This is just what nature programed them to do.
I have raised probably a thousand or more snails so have more of a chance to see these behaviors. Most people that have raised tons of snails know what is being talked about here.
Thanks Gale,for adding your story. With help like yours, we can educate people on not feeling guilty about their snails behaviors.
Hugs,
Joyce

[Lupin]

Now I feel sick and disgusted. I just lost my kuhlis and dojo to the canas. I have never fed all my snails meat, not even once. They get only commercial pellets, aquarium plants, vegetable matter, snail jello and calcium pills. The loaches were wellfed and did not exhibit any ill symptoms. The canas have been kept by themselves and occasionally with some of my plecos all their lives. I decided to keep them with my serpentine loaches for awhile thinking it'll be fine but the unexpected came.

The loaches disappeared mysteriously and I was quite shocked the snails look like they gained a growth spurt, even the hatchlings. This morning, I now have two egg clutches. This is how my canas repaid me for a food service consisting of a loach meat. I was distraught last night when I discovered my serpentine loaches missing. They don't normally lay eggs unless given a hearty meal beforehand and this does not involved meat until now. They were kept in my 15g with the kuhlis and dojos there temporarily while awaiting new tank orders to accommodate everyone. The setup itself has been maintained well and filtration maximized. The water has been changed as often as possible to cope with the bioload due to my refusal to mix the canas and the P. diffusa owing to the canas' ability to outcompete the latter for food.

[Annie Anderson]

Ohhh Lupin, how horrible!! I feel so bad! My canas are in with my brigs, spixies, khuli loaches, cory cats, guppies, plecos and red rams. So far I've been very lucky I guess--no casualties. But I know it's not because of how I feed them or treat them or anything--these killings seem to be random sometimes. No reason at all. So please, please don't blame yourself!! If anyone does his best taking care of his fish and snails it's you--you research everything and think so much about how to place them all so they'll all have the best of everything. You think of your snails as cute little hamburger faces who will be gentle and loving if given all they need--but they are still wild animals and instincts do win out. Even our beloved dogs will sometimes let us down by acting mean and unloving--to us, the people they adore!

Please accept my sympathy for your loss and disappointment.

[Lupin]

Annie, that's sweet of you. Thank you for the moral support. I just could not believe somehow the canas would one day attempt it. I mean I already was wary about them eating fish after reading a few threads about them whose behavior was triggered by meat but despite my efforts to avoid meat, this did not stop them. I think it's too much to be a coincidence the juveniles were spurred to hunt again after I lost mysteriously some baby snails during my vacation for 7 days two weeks ago. I don't know how the hatchlings died. They were either eaten by their older siblings or simply died of starvation. I refused to trust anyone to feed my snails while I was away for fear they will overfeed or worse, damage the snails when they try to handle them.

[pbgroupie]

Oh, Lupin, I do so hope your khulies are just hiding. They are very shy fish and have been known to bury in the substrate and hide in/under any thing they can. I've even had them survive outside the tank for over an hour inside of a piece of driftwood while I was trying to replant what the snails had dug up. The dojos would be pretty obvious and hard to hide (not in their nature either) but you may still have some khulies hiding. My fingers are crossed.

[Lupin]

Oh, Lupin, I do so hope your khulies are just hiding. They are very shy fish and have been known to bury in the substrate and hide in/under any thing they can. I've even had them survive outside the tank for over an hour inside of a piece of driftwood while I was trying to replant what the snails had dug up. The dojos would be pretty obvious and hard to hide (not in their nature either) but you may still have some khulies hiding. My fingers are crossed.

I don't know, pbgroupie. The kuhlis are really nowhere to be seen after a thorough search the day I discovered them missing. Thank you for your concern. I'll keep the canas separated without any fish involved just to be on the safe side although if I go absent for a week for a vacation again, the population number will scramble again since I suspect the older siblings are eating the hatchlings as a source of food.

[Josh Young]

This has been one of the most informative threads in regard to feeding these creatures on this forum. I now realize that one of the simple foods that snails can enjoy is feeder fish, they have lots of protein and calcium and vitamins, but must be dead before the snails can partake of them. From what I have read nearly all Pomacea species should enjoy a meal of intact sashimi.

No more rabbit food for my snails.

[Winterlily]

If that's your intent, it's best to raise your own (livebearers) so you an avoid the bacterial infections and parasites so common in the poorly kept pet store feeders.

[pbgroupie]

While the bridgesii/diffusa may help clean up the occasional dead and rotting fish, it is not a first food for them. The canaliculata are much more interested in a protein-based meal, but there have been several members reporting some canabalistic behaviors from those snails that have had a high-meat/seafood diet.

[Josh Young]

While I would love to have some Canas, alas I cannot.
not like they could stand the -10 F temps here in winter if they did escape though... it is a silly ban to impose on all regions for a species so widespread...

But my bridgesii/diffusa sure are pretty, they seem to like fish food, spinach and algae at this point, and I have plenty for now.

Thanks!

[scrup]

to chime in, I have seen my two Cana's slamming my Marisa cornuarietis (giant ramshorn) around before. Usually it was just a shoving match that the ramshorn would always lose, since the cana's were a good 3" larger than they were. They would actually swing the shell around and ram into them over and over until the ramshorn fell over or off the side of the tank, then shove them away from the food. A few times though I did see them pick them up and try and eat them, usually giving up after a while.

I also witnessed my cana's, on more than one occasion, eating live guppies and platties whole, usually at night after they were were asleep. Quite a scary sight.

After that I started throwing any dead fish into the snail tank. Waste not, want not.

I do have video of the shoving match, I will see if I can get it uploaded sometime soon. Probably speed it up a bit too if I can.

[teff]

The snails pack behavior reminds of of their cousins, the squid, who will gang up on an injured or hooked squid. Basic mollusk behavior.