Wild crayfish help please

BeckyCats

Fishaholic
Joined
Jan 16, 2016
Messages
570
Reaction score
225
Location
US
Hi All,
I found this crayfish in the road near a protected wetland in northeast MA. I looked it up and read that crayfish are invasive in MA so I didn't want to return it to the water, but neither did I want to let it die in the gutter (literally). As it happens, I have a 55 gallon freshwater heavily planted aquarium. I've been letting the fish die from old age and not replacing them because I would like to eventually have a single oddball species. A crayfish was actually one I was considering, so the solution seemed pretty obvious.

I have attached pictures of the crayfish in my tank. I am hoping for a few things by posting here:
1. Can anyone identify the species and sex?
2. Is it indeed invasive? If it is native, I will release it back into the wetlands where I found it (but not in the road, obviously).
3. What does it eat? I've read that crayfish eat everything and will rip up and devour my plants but this one is not doing that. I've tried feeding it 2 types of sinking shrimp pellets, dried seaweed (green & red varieties), and even a piece of scrambled egg, but I don't think it ate any of it. I don't want it to starve to death.

Thanks for any help.

Thanks!
20230718_131308.jpg
20230717_114421.jpg
 
If you contact your local department of agriculture (by website), they usually have a list of endemic species and introduced species.

If you look at the underside of the crayfish, males have 2 small bumps (1 on each leg) on the bottom set of legs (closest to the tail). Females have 2 small bumps (1 on each side) on the 3rd set of legs (starting from the bottom legs and going up). The following link has a picture of the small bumps.

Do not release the crayfish back into the wild if it has been in your aquarium. There are diseases that can attach themselves to the crayfish and get into the wild and decimate native fish stocks.

Freshwater crayfish are scavengers that will eat anything from plant matter to dead shrimp, fish, snails or any type of meat or fish food. A bottom feeding pellet and some lants will provide a good diet for them. Crayfish will also catch and eat live fish and shrimp so should not be kept with them.

Do regular water changes and gravel cleans to keep the tank clean. If the water quality deteriorates or gets too warm, the crayfish can climb out and wander off around the house. They are usually found in the bathroom or behind the fridge.
 
Welcome to TFF

Found this interesting: Crayfish are not native to Massachusetts, but they have been found in many of its waters. There are two species of crayfish, the rusty crayfish and the white river crayfish, which have been found in the state’s waters. They are an invasive species, meaning they are not native to the area, but were introduced by humans. Despite being an invasive species, crayfish are an important part of the food web, providing food for a variety of animals, such as turtles, fish, and birds. However, they can also cause ecological damage by eating the eggs of native fish and competing with native species for food and habitat. For this reason, it is important to keep a close eye on their populations and to limit their spread.
Source: https://adoptandshop.org/exploring-the-underwater-life-of-massachusetts-the-crayfish/
 
A healthy crayfish will eat just about anything that is or once was alive. They will eat plants, but often prefer other foods. Colin is right that you shouldn't return it to the wild. You could probably contact your local fisheries biologist for more info.

Be aware that it might be illegal to keep certain invasives in certain states. For example in Wyoming it is illegal to keep brook sticklebacks alive; if you catch one you are required by law to kill it! Same with zebra mussels and certain other inverts.
 
If you contact your local department of agriculture (by website), they usually have a list of endemic species and introduced species.

If you look at the underside of the crayfish, males have 2 small bumps (1 on each leg) on the bottom set of legs (closest to the tail). Females have 2 small bumps (1 on each side) on the 3rd set of legs (starting from the bottom legs and going up). The following link has a picture of the small bumps.

Do not release the crayfish back into the wild if it has been in your aquarium. There are diseases that can attach themselves to the crayfish and get into the wild and decimate native fish stocks.

Freshwater crayfish are scavengers that will eat anything from plant matter to dead shrimp, fish, snails or any type of meat or fish food. A bottom feeding pellet and some lants will provide a good diet for them. Crayfish will also catch and eat live fish and shrimp so should not be kept with them.

Do regular water changes and gravel cleans to keep the tank clean. If the water quality deteriorates or gets too warm, the crayfish can climb out and wander off around the house. They are usually found in the bathroom or behind the fridge.
Thank you for responding. That's good to know about diseases going from a tank to the wild. I can't imagine letting anything loose into a waterway for the most part, as that's exactly how we get invasive species in the first place. I had originally thought that if this was a native species and actually belonged there, that I could return it, but you're right about it being a bad idea. I guess I have to keep it now. I don't mind, as long as it eats. It seems to have ignored the sinking pellets I've put in there so far, but maybe it's eating when I don't notice.

I do water changes every other week. There are 2 small tetras left in the tank and many plants, so the bioload is minimal. I have sand substrate so no gravel cleans needed.

I did read about their propensity for escape (and after all this one was found wandering) so I blocked up the possible exits. It is a big deal that it NOT get out, because honestly, I think if my husband found what is essentially a giant bug walking around the house, it could be the end of our marriage. 😆

I'll have to wait for an opportunity to see the underneath of it to sex it. I have little desire to pick it up tbh. I thought perhaps it might be a female because the claws are small, but that could just be the species.

Thanks again!
 
Welcome to TFF

Found this interesting: Crayfish are not native to Massachusetts, but they have been found in many of its waters. There are two species of crayfish, the rusty crayfish and the white river crayfish, which have been found in the state’s waters. They are an invasive species, meaning they are not native to the area, but were introduced by humans. Despite being an invasive species, crayfish are an important part of the food web, providing food for a variety of animals, such as turtles, fish, and birds. However, they can also cause ecological damage by eating the eggs of native fish and competing with native species for food and habitat. For this reason, it is important to keep a close eye on their populations and to limit their spread.
Source: https://adoptandshop.org/exploring-the-underwater-life-of-massachusetts-the-crayfish/
Hi, Thanks, yes, this was the first one I found as well when I looked it up. The site's information seems to be incomplete however as I found other sites that mention different crayfish in MA, and also, the crayfish I have doesn't seem to look like either of the species it mentions. I do think it is correct in stating that crayfish are not native species here. Especially in wetlands.
 
A healthy crayfish will eat just about anything that is or once was alive. They will eat plants, but often prefer other foods. Colin is right that you shouldn't return it to the wild. You could probably contact your local fisheries biologist for more info.

Be aware that it might be illegal to keep certain invasives in certain states. For example in Wyoming it is illegal to keep brook sticklebacks alive; if you catch one you are required by law to kill it! Same with zebra mussels and certain other inverts.
Oh dear! I'm afraid to ask the state agency now because I will NOT be able to kill it. I couldn't just drive by it and leave it to die; actually killing myself would be impossible.
I was also afraid that it might get back to the water and breed or eat tadpole eggs, or commit some other mayhem. If it is native, then that's all part of life. If it's a descendant of some angler's bait that got loose, that can disrupt the ecosystem. Of course I realize that one single crayfish may not make that much difference, but you never know. It seemed irresponsible to let it go back to the water and cruel to let it die. That's why my aquarium seemed like a good compromise.

I guess I'll call a wildlife group just to make sure I'm not violating any laws. But if they want it dead, they'll have to come get it and do it themselves. Hopefully it will be fine though. I do find it very interesting and it is already digging in the sand and finding lots of hiding places. 😊
 
Of course I realize that one single crayfish may not make that much difference, but you never know. It seemed irresponsible to let it go back to the water and cruel to let it die. That's why my aquarium seemed like a good compromise.

I guess I'll call a wildlife group just to make sure I'm not violating any laws. But if they want it dead, they'll have to come get it and do it themselves. Hopefully it will be fine though. I do find it very interesting and it is already digging in the sand and finding lots of hiding places. 😊
One crayfish wouldn't make much difference, but if it found a friend, and they spawned? That could make a huge difference. It sounds like this species is already on the loose in your waters, but now that you've removed it, it should stay removed.

I think calling your fish and wildlife agency is a good idea. If it does need to be culled, I'm sure they would be willing to take care of it for you.

Crayfish are really fun to watch. They do enjoy moving sand and gravel from one place to another. :)
 
I did read about their propensity for escape (and after all this one was found wandering) so I blocked up the possible exits. It is a big deal that it NOT get out, because honestly, I think if my husband found what is essentially a giant bug walking around the house, it could be the end of our marriage. 😆
At least it's not an octopus, lol. I actually kept a couple in a half full 10 gallon in an elementary classroom for a couple of years. The half full was to prevent escape. King cray ate the other one over spring break
 
Oh dear! I'm afraid to ask the state agency now because I will NOT be able to kill it. I couldn't just drive by it and leave it to die; actually killing myself would be impossible.
you don't have to call them, just look on their website
 
One crayfish wouldn't make much difference, but if it found a friend, and they spawned?
Exactly! That was my concern.

you don't have to call them, just look on their website
I tried but did not find what I was looking for.

I would just hang on to the cray, and let it live out the rest of it's natural life in your tank ;)
That was my plan. I just hope it eats something. It is not eating the sinking pellets. I'll try the algae wafers next. I'll take a look in my lfs as well to see if they have anything that might be less vegetarian that sinks. I think most of my sinking foods are plant-based.
 
Exactly! That was my concern.


I tried but did not find what I was looking for.


That was my plan. I just hope it eats something. It is not eating the sinking pellets. I'll try the algae wafers next. I'll take a look in my lfs as well to see if they have anything that might be less vegetarian that sinks. I think most of my sinking foods are plant-based.
Omega One Veggie Pellets have more animal protein in them than you would think from the name.

 
Omega One Veggie Pellets have more animal protein in them than you would think from the name.


That's good to know. I do have those but haven't tried them yet. Hopefully they'll be appetizing.


Do you think the crayfish will find the flakes? I'm concerned that flakes will get stuck in the plants and just rot away before the crayfish finds them.

If anyone is interested, I did call the wildlife and fishery folks here. I was told that there actually are a few native species but crayfish are "understudied" here so they can't be sure whether mine is a native or introduced species. They have not found crayfish to have a big impact on MA waterways at this time (at least not yet, he said), but obviously it is not great to have introduced or invasive species, especially in wetlands which are protected and vulnerable.

He said that there is nothing illegal about taking the crayfish home or keeping it. It is seen as no different than gathering one up to use as bait, as far as the impact on the environment. I asked if that sort of thing ever happens again, should I put the animal back in the water or remove it. He said it is fine to put it back.

Interestingly, he wants me to send pictures of it, top and bottom, send the size, where I found it, the date, etc. He's going to forward the info to the "crayfish guy" to keep as a datapoint.
 

Most reactions

Back
Top