Feeding preference of an introduced population of Cherry Shrimp

[dw1305]

Hi all,
I was looking at an <"Asellus food preference paper"> (apparently the shed leaves of Alders Alnus spp.), and it linked to this paper, about the Cherry Shrimp (Neocardinia davidi). Schoolman & Arndt (2017) <"Leaf-litter preferences of the introduced freshwater shrimps Atyaephyra desmarestii and Neocaridina davidi"> Crustaceana 90. which also points towards Alder leaves as a preferred food item.

......while the ornamental Species Neocaridina davidi was released in 2009 into a small tributary of the Erft River (North Rhine Westphalia, Germany), where it has thrived. Both species use leaf-litter as a significant food source. In this study, we assessed a reproducible method to compare the preferences of this two shrimp species for decaying leaves of four different species of deciduous tree: alder (Alnus glutinosa), Italian poplar (Populus xcanadensis), pedunculate oak (Quercus robur) and goat willow (Salix caprea). We also determined the relevance of A. desmarestii and N. davidiin leaf-litter breakdown. Adults of both species showed a significant preference for leaves of alder and Italian poplar

....... Diurnal consumption rates were determined for N. davidi. It consumed 51.0% leaf litter dry weight per body dry weight per day. Alnus and Salix leaves (including biofilm) made up the majority of the diet of Neocaridina, followed by Populus and Quercus leaves

.........Our results demonstrate the distinct relevance of leaf-litter in the diet of freshwater shrimps, and their role in leaf-litter breakdown. While the invasion potential of A. desmarestii seems to be relatively low, at least for now, N. davidi has thus far been a very successful invader.

I've just looked it up, and the Erft river is "thermally polluted" and has Vallisneria etc. growing in it.

cheers Darrel

 

[zozo]

Hi all,
I was looking at an <"Asellus food preference paper"> (apparently the shed leaves of Alders Alnus spp.), and it linked to this paper, about the Cherry Shrimp (Neocardinia davidi). Schoolman & Arndt (2017) <"Leaf-litter preferences of the introduced freshwater shrimps Atyaephyra desmarestii and Neocaridina davidi"> Crustaceana 90. which also points towards Alder leaves as a preferred food item. I've just looked it up, and the Erft river is "thermally polluted" and has Vallisneria etc. growing in it.

cheers Darrel

Intersting... I dumped some Cherries in the 125 litre outdoor bucket curious if the would survive and thrive.. Well if they survive Germany they also will in my big bucket.. North Rhine Westphalia is next door for me, 45 minutes drive and i can catch wild cherries in the Erft.. haha.

Also had a few outdoor till november and took it indoors. I noticed them getting more robust and dark red almost brown in color. It was pretty cold when i took 'm in, but they do not seen to be bothered.

 

[rebel]

https://www.timeanddate.com/weather/germany/dusseldorf/climate

Looks like the temps don't drop below 1 degree C. Perhaps that's the limit?

 

[zozo]

https://www.timeanddate.com/weather/germany/dusseldorf/climate

Looks like the temps don't drop below 1 degree C. Perhaps that's the limit?

Could very well be, the North West of Germany also is rather low country, relatively lower at sea level. It's near to our Dutch border at the same longitude as where our country the Netherlands (low lands) get rather low at 5m above sea level getting even lower further north.

The more you go South and East you'll go up the mountains, i live 135m above see level at the foot hills of the German Eifel and Dusseldorf is 45 minutes N-E down hill from my place. And my average winter temps are already a tad lower. It's funny to live at such a climate border, sometimes i only have to drive less than 20km S-E to go skiing in the snow and still have +0 temps at home.. 🙂 But it also can drasticaly shift we can have -18°C too occasionaly.

 

[tam]

I'm sure I've read somewhere someone had them in an outside tub that had ice on the surface (although I don't know how insulated/what the temp was down the bottom).

 

[dw1305]

Hi all,

've just looked it up, and the Erft river is "thermally polluted" and has Vallisneria etc. growing in it.

It says in <"Alien aquatic plants in a thermally...... "> that water temperature doesn't fall below 10oC. This paper also has a map.

I don't know how far the cherry shrimps have spread, but presumably the water gets cooler as it goes down-stream from the warm water source (the drainage from lignite mining and associated power station).

This one <"Population dynamics of the invasive freshwater shrimp Neocaridina davidi in the thermally polluted Gillbach stream (North Rhine-Westphalia, Germany)"> says at least one cherry shrimp has been found in the lower Rhine, and this one <"On the occurrence of three non-native cichlid species including the first record of a feral population of....."> says

In Germany, non-native convict cichlids (Amatitlania nigrofasciata) and tilapia (Oreochromis sp.) have established populations in the Gillbach, a small stream that receives warm water discharge from a local power plant. Here, we report on the discovery of spotted tilapia (Pelmatolapia mariae) in the Gillbach, the first record of a reproducing population of this species in Europe.

cheers Darrel

 

[mort]

I'm sure I've read somewhere someone had them in an outside tub that had ice on the surface (although I don't know how insulated/what the temp was down the bottom).

I've seen this as well. I think someone had them in a 100 gallons vat that was above the ground. They also kept ricefish in the same way. May have been cory mcelroy and I know he's now based in Washington.

 

[rebel]

I didnt realise thermal pollution was a thing!

 

[dw1305]

Hi all,

I didnt realise thermal pollution was a thing!

There is a UK "warm water" thread in <"Remember the Hotties...">.

cheers Darrel