Mulgrave River - Snails, Nerites & Red Val

[fishmosy]

Finally getting around to posting the rest of the field trip pics and videos. Next up is the Mulgrave River, located near to Bob's place. in fact, Bob and I walked to this location from his place.

This is a shallow section where the red Valisneria occurs, with some other plants. Bob and I also found some nerites (Neritina pulligera) and the ever-present Stenomelania denisoniensis snails (grey foot colour variant).  

Water parameters were:

pH: 7.0 - 7.1

GH: < 20 ppm

KH: 10 - 20 ppm

Temp: 22.5*C

TDS: 29

The water in this section was around a foot to max. 1 metre.

The red val

Found the Stenomelania snails near the waters edge

We first noticed the nerites by spotting their egg cases which were everywhere when we started looking.

They were in the areas away from the plants, plenty of rocks (not sand) and a bit of timber and leaf litter.

We found the nerites by turning over rocks, they were generally underneath, but occasionally not. The best way to tell where they were was to spot the white eggs (newly laid). The eggs turn yellowish with age.

Also found a freshwater sponge under the rocks in this area

Video of the nerites' habitat

 

There were also a few Mulgrave gudgeons hanging out in this area

 

We then moved downstream slightly to where the water ranged in depth from 1 metre to 2.5 metres. I apologise for the bumpy filming but I was fighting a swift current.

 

 

 

 

Edited July 24, 2015 by fishmosy

[fishmosy]

Also coming from the Mulgrave is a gold variant of Stenomelania denisoniensis, with either gold spots on black or a completely gold foot. We have named this variant S. denisoniensis "Mulgrave Gold". 

This is the variant Bob has alluded to on the forum a couple of times recently. However we are not certain whether it breeds true, and whether the colour will be maintained in aquaria. So far, mine are generally holding colour but don't have the same impact as the colouration they had in the wild.

Here is some shots of them in their natural habitat and in my tank.  

 

 

 

 

 

Finally some shots of a cheeky fish way downstream

Edited July 24, 2015 by fishmosy

[Callan]

Wow Fishmosy stunning photos. Was that Blyxia or val and elodea I saw? You could see the area of weeds that the shrimp would be a nice habitat for them, although from what you are saying maybe the flow would have been too strong.

The eggs on the rocks did they belong to the Mulgrave gudgeons?

You can see in the first few pics the weed basically being pushed flat which is a great way to show how strong the flow was.

Great work Fishmosy thanks for sharing

[fishmosy]

The red stuff is a type of val, the long green ones are a type of aponogeton, and the other green stuff could be elodea, but I'm not too sure.

There were no shrimp (at least that we saw) in this area, probably because there are too many fish and eels. Saw a half dozen eels about 20cm long in the 50metres or so of river that we looked in. Plus lots of fish, including rainbows, barra, jungle perch, gudgeons ect.

I think all the eggs are from the nerites unless I didn't notice some fish eggs in some of the pics? 

[Grubs]

I'm so envious. Brilliant photos.

[kizshrimp]

Excellent work getting some more pics up mate, thanks. Great coverage, as close to being there as we could hope for. That stand of red Vall is amazing. Those yellow foot Stenos are lovely, something different. 

I'd reckon the Elodea looking thing is Hydrilla verticillata but I can't see the details well enough in the pics. I doubt a cold water species like Elodea is invasive up north where a pantropical equivalent occurs naturally.

The Nerites are truly excellent algae eaters. I actually have to switch them from tank to tank to keep up with their demand for algae and I think they're eating it quicker than it grows. They absolutely, completely clean rocks and glass if you're patient, which some "reviewers" online are obviously not. They don't really like soft acidic water; they're ok at about 6.4 and 4-6 dGH but some are prone to shell erosion and all are more active at 7+ and harder. They don't lay eggs in soft acid water and probably wouldn't last long-term in it. 

I've got 3 species here and eggs in 2 tanks now - all from the same species unfortunately. One of the tanks can be stripped and converted to saltwater for a veliger raising attempt - but that's a whole different thread. I do highly recommend Nerites to anyone interested. 

[Callan]

I just blew the picture up and you are right Kiz. The structure of the leaf is not the correct shape to be elodea. I had more of what I would describe as a maple leaf look to it. Nice pick up. The red val does look amazing I have seen it in a few forms including Gigantica but never it with red foliage before.

Once again Fishmosy the pics are amazing.