Hiya I've been following a few threads here and

[GTZA]

[color=#006600]BigCarpio[/color] wrote:

...over a certain size they (carp) do not breed/spawn anymore... And they have a very important place in the hierarchy of a carp population. Take them out, see what happens.

BC, I've heard reference before to big carp not breeding any more. Do you have any data on what size/age is the cutoff point and what the reasons for this are? Also, what is the importance of big carp in the population hierarchy in the South African situation?

 

[Ryan]

Just to come to BC's defence - I have noticed that during spawn time the majority of spawners are below 10kg - this is just a personal experince on my Part - I fish them when they are spawning as the big mamma's are to be found just on the periferies of the spawning ground along with vast numbers of Barbel - me thinks they are cashing inn on all the extra protein......

 

[MadCarper]

Ryan, didnt you mean to say the majority of spawners are ABOVE 10kg? I've seen this plenty times. We fish up to when they start spawning, and normally go closer to see what size fish are part of it... one is sometimes amazed at the sizes of carp coming by during this frenzy. (Best time to fish for big carp is just before and after spawning...)
But at the same time I have been to 2 dams(one farm dam and one dam in Jhb) where there is an overpopulation of small carp, and where we have really battled to catch anything bigger than 7kg......, and then you only see carp of 5-6kg doing the spawning. Maybe not scientific evidence, but it says alot in terms of one of my points above...big carp dominating the spawning process...There are alot less big carp in a dam, and many more smaller carp...so when the big carp are removed, many more smaller carp takes over the spawning process, which mean multiplying of spawn.

A question I always have is, if big carp over a certain weight dont breed anymore, one could surely have a dam with big(non-breeding) carp in it, and never have to worry about the dam becoming overwhelmed by small carp, or what.

GTZA, I had an article on both carp breeding, as well as the carp population dynamics, but will have to go dig it up... But I will put it up here.

As far as I've read, at a certain weight the female carp's breeding organs(eierstokke) harden up, meaning the carp cannot produce spawn/eggs anymore...

I must actually go read up again, hehehe...:sha

 

[Ryan]

[color=#006600]BigCarpio[/color] wrote:

Ryan, didnt you mean to say the majority of spawners are ABOVE 10kg? I've seen this plenty times. We fish up to when they start spawning, and normally go closer to see what size fish are part of it... one is sometimes amazed at the sizes of carp coming by during this frenzy. (Best time to fish for big carp is just before and after spawning...)
But at the same time I have been to 2 dams(one farm dam and one dam in Jhb) where there is an overpopulation of small carp, and where we have really battled to catch anything bigger than 7kg......, and then you only see carp of 5-6kg doing the spawning. Maybe not scientific evidence, but it says alot in terms of one of my points above...big carp dominating the spawning process...There are alot less big carp in a dam, and many more smaller carp...so when the big carp are removed, many more smaller carp takes over the spawning process, which mean multiplying of spawn.

A question I always have is, if big carp over a certain weight dont breed anymore, one could surely have a dam with big(non-breeding) carp in it, and never have to worry about the dam becoming overwhelmed by small carp, or what.

GTZA, I had an article on both carp breeding, as well as the carp population dynamics, but will have to go dig it up... But I will put it up here.

As far as I've read, at a certain weight the female carp's breeding organs(eierstokke) harden up, meaning the carp cannot produce spawn/eggs anymore...

I must actually go read up again, hehehe...:sha

Eish my bra but either you or I is dazed and confused. You contradicting yerself by saying big carp don't spawn and now they do. As I say in my personal experince I target the bigger ones when the fish are spawning - and as I have stated by my observations most of the spawners that I have seen are below 10kg but I guess this can vary from venue to venue. Next spawn season - I rate we grab the bow and go and shoot a few of the bigger specimens just to confirm what wt they are - what do you think?..................We can get skrops (he got a bow) miles with his fins and speargun....

What wt do they freeze up - please can you also post us the reference to this ie - the book you found it in etc.

I like your idea of a big speciemen  non breeding dam - jeez but I think we have finnaly helped a rabid speciemen dude think outta the box - congrats and welcome to ourside...........LOL 

 

[GTZA]

Ding, ding, round No 3.

Ryan, my questions to BC was not intended to attack, rather to get some clarification. And very pertinent to the idea of protecting larger specimens in the context of management of a species with potential for both environmental harm and social/economic value. And I think that the apparently conflicting posts of BC and yourself illustrate this dilemma. If one is contemplating management of populations to allow for preservation of "infertile" specimens, it is imperative to know the reasons for the infertility (age vs weight/obesity) and whether this condition is reversible or irreversible. This is well understood in mammals but I don't know how much is known in the pisces or how much we can extrapolate.

The notion that infertile specimens play a role in population dynamics is new to me and I would like to obtain more information on this. It at least raises the issue of social structure and order and/or family groupings, which of course introduces an entirely new angle of thinking.

 

[MadCarper]

Lol, no man. I did not contradict myself, hhehehe... Big carp spawn yes, but over a certain size they dont....Now stop confusing me dammit, lol!!!


I would think that if you have seen mostly fish under 10kg spawning, hmm... I'd say the dam must be overcrowded, hehehe...


GTZA, I did not take your questions as an attack either, hehehe. And I would like to clarify my statements, as soon as I get what I was looking for...! Knowing how my wife operates, she's probably "put the article away" somewhere, hehehe...