Freshwater shrimp/ river shrimp/ gammarus/ scuds

[keegan]

I've often wondered why brine shrimp aer so popular to feed to freshwater fish and newts. We have shrimp in our river that I would think to be very appropriate - very tiny when young, up to maybe a cm. They swim and are active, from what I have seen, but are not super-fast. It seems that they would survive longer in a tank than worms or brine shrimp, and be a more subtantial meal than daphnia = perfect for newts?

A little bit of searching on the net = they are some species or close relative of gammarus (commonly called scuds)? Now that rings a bell - I thought I saw a brief discussion about scuds on Caudata some time ago (can't find it now) (hmmm... a searchable discussion board would be a neat feature!)

Any comments? People who have used or raised scuds for thier newts? I have half a mind to drag a bucket along the bottom of the river to try and get a starter culture - of course... we're frozen solid for a few months yet...

Thanks

Keegan

 

[jennifer]

Hi Keegan, good ideas! I think the only reason brine shrimp are popular is that they are very available. Pet shops stock the cysts for hatching tiny brine shrimp, and they sell the adults, live and frozen, for feeding larger newts. But you are right, freshwater shrimp are really the ideal food for newts. If you can get a culture going, you would have a great food source. I haven't tried them, but I wish I could. (Unfortunatly, we have a terrible mosquito problem here, and are discouraged from having any standing water outdoors.)

The search function on this forum works really well. Look at the menu on the left-side frame under "Utilities". See where it says "Keyword Search".

 

[edward]

Hi All,
Scuds (Amphipods) are fairly easy to culture. You can either capture your own starter culturers or get one from (I think, lfscultures.com). Most of the ones you are seeing are deitrovores or are scavengers on plant and animal debris. However they are known to be intermediate hosts for tapeworms for fish and birds.
If you want to culture them check out the page at http://www.mn-aquarium.org/masartab.htm
There are also freshwater shrimp aka ghost shrimp that can also be cultured for feeding to animals. These will take a couple of tanks to culture them as you cannot keep the different size classes together as the larger shrimp will eat teh smaller shrimp. The breeding adults are kept in a tank that has a gentle overflow into the second tank, the reason for this is because the larva are part fo teh freshwater zooplankton when they hatch. They will flow over into the second tank where they will float head down at the surface. The larva should be small floating food items and/pr small live food items like freshwater planktons.
Some thoughts, (maybe Kai will have some more)
Ed

 

[kai]

Yup, amphipods are good food (calcium, lots of carotenoids for color, too) and pretty easy to culture. However, some newts won't readily accept them or need quite some time to hunt them down (OTOH, this could also be seen as an advantage to keep them busy). The North American Hylaella azteca is especially easy to cultivate but of somewhat small size - if you need larger food items try other amphipods from your local waters...

I like to feed Asellus aquaticus which is more readily taken by most newts and also makes a good, semi-permanent addition to any newt tank.

Culturing both of these scavengers needs a bit patience (i.e. start with a good amount of specimens not just some minor "starter culture"...) but eliminates any possible problems with parasites. Collecting them in fish- and newt-free springs should also work (most of the time - have had not any problems yet).

It's also possible to culture freshwater shrimp in good numbers - Neocaridina spp. can be pretty productive, too. Again, get plenty of them (which can be expensive) and do your homework.

For larger caudates, I would also guess that really young crayfish would make a nice addition to the diet. For my Pachytriton, I might try an unidentified Procambarus species which can't be kept from breeding by any means...

(I haven't yet because Procambarus spp. carry parasitic fungi which are lethal to our European crayfishes and, thus, it's not admissable to pour any wastewater from the respective tanks into the sink...

)

Best wishes,
kai

 

[heymoe]

I have a stream not to far away that has crawdads in it. Is there a way to test for parasites before I introduce them to my tank?

 

[kai]

You can see the parasites under magnification - however, if you find nothing, this could have several reasons like too little experience or low density parasite population...