Hi All.....I'm on here to learn...I get the impression there are a lot of guys on here who know their stuff

I went looking for freshwater shrimps this summer down at the lough....turned over a few flat stones and bingo...lots of the dark brown olive ones you would expect to find, but very surprising was the number of light grey ones...transparent(ish) but very noticable..a very light blue grey. They stand out like a sore thumb against the bottom....my question.....are these usual ? If so, why are they that colour and are they common in all freshwater where the dark ones thrive. Do the trout eat them as well, if so, they would be a better "fly" / imitation to use because they are so easily spotted by the trout presumably??

Any advice / help appreciated..

Thanks....

Photos would have been good if only to eliminate smaller male shrimp from larger female examples.

Which lough? The reason I ask is that the native freshwater-shrimp of Ireland is Gammarus duebeni celticus.
Still native also to the Isle of Man and parts Brittany, France. They are under threat from the more aggresive invasive (to Ireland) Gammarus pulex.
They also interact with a hookworm parasite that could be present, and is now endemic in parts of Ireland, has been mentioned elsewhere...

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Save the softmouth trout

Thanks Ephemerella..........Lough Erne, Ireland,....all I was asking was it normal for shrimps to be that grey / light blue / almost transparent colour. If so, are they common in that colour (they are in Lough Erne obviously!) or is this a freak? Are you aware of this in any other waters?

Thanks again for the reply Ephemerella

:: Invasive Alien Species in Northern Ireland :: Habitas :: National Museums Northern Ireland

Looks like G. pulex has invaded your lough from the north.

I think your "albinos" are recently mated females which have shed their hard skin for mating - see 'life cycle' part highlighted in red,



"River Lagan and its tributaries, and Loughs Neagh and Erne, all have large G. pulex populations.
G. pulex is also now found in the Republic of Ireland, such as the River Boyne and rivers around Dublin. It is likely these originate from Northern Ireland populations. Studies show the species can live in nearly all freshwater habitats in Ireland, but it might not invade very high altitude streams where the native shrimp, Gammarus duebeni celticus, still dominates.

Life cycle
The life cycle of Gammarus pulex is complex. Males grab and hold females before deciding which one is likely to produce lots of eggs. Then the male carries his chosen female for several weeks until she sheds her skin and the male can mate with her. He then lets her go and she carries the developing young in a brooding pouch. After about a month, the young shrimps swim out of the brood pouch, and a few months later they can breed themselves. As females can produce up to 50 young each month, the population soon grows."

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Save the softmouth trout

Thanks again Ephemerella. That's what I call a reply . The mating ritual sounds interesting.....I wonder what the trout make of it all.....perhaps a "doubled up" pattern would increase chances of a take !! a kind of two for one offering
Thanks again.....a most enlightening reply..

Hi', 11foot5, Do you play basketball? Sorry about that.
The invertebrates, generally, shed their outer skins (exoskeltons) in order to expand, which is easiest to do while the new outer coat is still soft. Crabs do it, so do shrimps and larvae of aquatic insects. The larvae of upwinged flies for example can have twenty plus 'instars' during their growth, and I often find quite pale coloured LDO nymphs, for example, among slightly darker ones. With our mainland shrimps, we find them in shades from pale fawn/olive through to quite strong salmon pink. Cheers Ja

Thanks for that jada......and no, 11foot5 comes from a rod I built a while back...an 11 foot #5 (Sage z axis by the way and a damn fine rod it is !!).

Since posting a few hours ago (and due mainly to the replys) I've read a paper on the G. Pulex and several other extracts . I have to say it's fascinating...parasites, their colour and the effect it has on the shrimp etc. Very interesting indeed

A very big thanks to Ephemerella and Jada...

The year I fished at Moidart I saw mating shrimp swimming in the margins and I was struck by how much they resembled a #10 Invicta in shape and colouration. Tried one on the cast for a few days on different lochs in the area and caught fish on it. I was already catching fish on my usual flies before that though so it isn't conclusive evidence that it works as a representation.

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Don't worry, be happy.
Sandy
Carried it in full, then carry it out empty.

Hi', Fishtales and all, Just a thought on the representation of shrimps by artificial dressing -- the standard dressings are almost all tied on curved hooks, to copy the shape of the shrimp at rest, and yet we pull them at various rates of retrieve. But we all know that when they shoot off, they take on an almost straight body shape. Why do we bother with specialist hooks? Ja

When they shoot away as you say they become more elongated but when they are just bumbling along doing there own thing they maintain the crescent shape and this is what the trout see when hoovering them up in the margins and off the bottom. The Invicta that I was using still had that crescent shape maintained by the shape of the wing over the back.

__________________
Don't worry, be happy.
Sandy
Carried it in full, then carry it out empty.