Bleak in the waveney? Photo id please

[Mark Crame]

Thanks for all the replies guys; I'm glad it's not a bleak as although It would put my species count up by another 1 to 26 from start of July it'd not score in the comp because the voucher isn't in the shot...the reason I was unsure was after seeing the entry of a mate further north who called a fish that looked similar to these a bleak...and I wasn't sure his were. At the time of capture these, and I get quite a lot (these are probably by the iron bridge at beccles) generally stand out as being pale dace/bream/roach (they vary) and are usually around 4-5 inches long and I think no more about it. usually have a pale shimmery line along the flanks, slightly darker and pearlescent. Probably have some more pix somewhere, will take some more next time if it's of interest.

 

Thanks again, really appreciate your efforts!

[Latimeria]

Never seen or heard of a Dace x Roach hybrid, but given where the river runs, anything is possible, sure I've seen Human x Water Vole hybrids down that way.

I can imagine that following the delayed Spring this year there might be some oddities coming through in the next few years, and it seems that there's a bit of experimentation, intentional or otherwise, on some fish farms (given the prevalence of not-rights in commercials). Wonder if there's been any stocking in that area, maybe to replace a fish loss in a tributary?

The origins of this fish will continue to peck at a corner of my mind for some time, I suppose that if for some reason suitable spawning habitat wasn't available for the Dace, some could be delayed enough to overlap with Roach and decide that any hole's a goal.

Edited August 16, 2013 by Latimeria

[Mark Wintle]

Dace x roach hybrids are theoretically possible but no known scientifically-proven examples. Different triggers for spawning - dace = daylight hours - roach = temperature - make coincidence of spawning unlikely whereas it's very common with rudd/roach/bream, all of which have temperature triggers . I'd suggest both fish are dace, pure and simple.

[gozzer]

We used to get plenty of these fish from Bedale Beck, a tributary of the Yorks Swale. We had quite a few discussions as to what they were. We got ordinary dace, then those that looked a bit 'roachy'. Without any scale counts, but just going on the general look of the dozens we caught, I decided, (rightly or not), that they were dace. I'd never heard of dace/roach hybrids, although the water did contain plenty of roach. The strange thing was, we never caught any of these fish in the main river, just in the beck.

 

John.

Edited August 16, 2013 by gozzer

[Anderoo]

Definitely not bleak - next time I'm at the Thames I'll get a bleak pic. The biggest thing you notice with them is the huge pale yellow eyes and little upturned mouth. The second one does look a bit roachy doesn't it...might have a little bit of everything

[Latimeria]

I've saved them and opened them with a simple paint programme, the upper fish has 6 clearly visible scales in a diagonal line between the lateral line and the base of the dorsal (there is a 7th, it's hard to see but it's there).

The lower fish has 8 clearly visible scales along the same line, which shows that there are differences in body proportions.

The upper fish has the dorsal and pelvic fins inserting roughly opposite one another, as in Dace.

The lower fish has the pelvic fin insertion noticeably anterior to that of the dorsal, as in not Dace.

There was a recent thread on Trad Angling where someone was puzzled over the identity of some fish they were catching alongside Dace, I'll go and have another read of that.

Serendipitously, I've got an Ichthyologist friend from Finland arriving here in the next hour, I'll ask him for his opinion.

[Vagabond]

We used to get plenty of these fish from Bedale Beck, a tributary of the Yorks Swale. We had quite a few discussions are to what they were. We got ordinary dace, then those that looked a bit 'roachy'. Without any scale counts, but just going on the general look of the dozens we caught, I decided, (rightly or not), that they were dace.

Interesting.

 

According to Yarrell (who was notorious for "inventing" new species) there is the Dace Leuciscus vulgaris (fifty or more scales on the LL) the Graining Leuciscus lancastriensis (LL count 48) and the Dobule Leuciscus dobula of Agassiz

 

Houghton (1879) mentions and illustrates all three, and (rightly IMHO) suggests they are all varieties of dace.

 

However, that does show that anglers and ichthyologists were noting differences in Dace well over 100 years ago.

 

...and like Latimeria, the more I look at that second picture, the "roachier" it gets.

Edited August 16, 2013 by Vagabond

[Phone]

Question,

 

Is there not a DNA data base source in the UK? (Costs $50 plus postage here). Of course, you have to kill the fish. Is that an issue?

 

Phone

[Mark Wintle]

Question,

 

Is there not a DNA data base source in the UK? (Costs $50 plus postage here). Of course, you have to kill the fish. Is that an issue?

 

Phone

No need to kill the fish; a single scale can be used for DNA sampling. Cost is similar.

[Peter Waller]

At the moment the Waveney is far from bleak! Some darn good roach coming out right now.

 

As for Mark's fish, no at all uncommon. Not that I know what they are though, always assumed they were hybrids, either dace or bream/roach crosses.