the fresh affect

[nathank]

Hi all, fished bond uni the last two nights in a row for one run... and it was a good one.. anyway dropped that fish right at the bank. One thing i did notice though was that my bait was dying withing about five to ten minutes. the first night i was using the local herring, the next night i thought i would use something a bit more tolerant to the fresh and picked up a few mullet at a different location. Same effect the bait lasted around ten minutes and then was dead. i am thinking that the fresh is either on the bottom or its salt and has been stripped of all the oxygen??? anyway its pretty strange. had two pots out with some big primo bait in and both and pulled a blank in an otherwise very productive spot... any thoughts anyone?? oh yeah i am fishing the lake Orr side.

[mangrovejacks]

If herring are dying I am pretty sure it's the fresh or lack of current doing it. Could also be water temp but usually it's fresh and/or lack of current I have found.

[nathank]

hmmm... "lake" Orr sorta gives the theory a bit of a nudge mate.. there isnt a current in the lake most of the time. but at the same time i cant work out why the mullet died also.. im sorta leaning towards an oxygen depletion after a bit of research but i just dont know

[Genesis]

Mate of mine lives along Southlake Dr with backyard access to the lake and he paddles out on his kayak around Lake Orr almost every evening. Lately he has been noticing a lack of activity around the lake whereas he used to see heaps of baitfish gathering around the banks and flashes of good size trevallies smashing them.

I am guessing lack of oxygen too.

[mangrovejacks]

hmmm... "lake" Orr sorta gives the theory a bit of a nudge mate.. there isnt a current in the lake most of the time. but at the same time i cant work out why the mullet died also.. im sorta leaning towards an oxygen depletion after a bit of research but i just dont know

Can only tell you what I've picked up over the years. Given your issue refers to only a lake perhaps your baits are too deep? Most livies die when they are expected to swim on hooks in water that's too deep - pressure, temp and oxygen come into play.

But as previously mentioned, lack of oxygen is more than likely an additional factor in this case.

In any case, if you want to catch decent Jacks you should move spots

[wayno60]

no no,,,, we have the spot for jacks its the big nasty trevs that he's after.....

As the rain tumbles down again.....

Nath it might be april be we get down there with no fresh water

[nathank]

yeah wayno is right.. lol, i know where jack lives haha. livies will live and swimm at all kinds of crazy depths, having put livies deep off the back of montague island can atest to this.. and we are talking 6/7 meters tops at lake orr.. anyway i moved spots last night (dodging lightning all the way) closer to the broadwater and had a different result... the livies remained exactly that ... alive. anyway just outa interest the run i had on monday night was a genuine 8 to 10 kg jewie.. lost it right at my feet (pulled hook) and the hook and sinker flew out of the water and smacked my poor mate in the head lol.

[mangrovejacks]

yeah wayno is right.. lol, i know where jack lives haha. livies will live and swimm at all kinds of crazy depths, having put livies deep off the back of montague island can atest to this.. and we are talking 6/7 meters tops at lake orr.. anyway i moved spots last night (dodging lightning all the way) closer to the broadwater and had a different result... the livies remained exactly that ... alive. anyway just outa interest the run i had on monday night was a genuine 8 to 10 kg jewie.. lost it right at my feet (pulled hook) and the hook and sinker flew out of the water and smacked my poor mate in the head lol.

Looking forward to some Jack pics and measurements nath.

[Ben D]

Its very common to have oxygen depletion in still waters when the denser , saltier water is overlaid by a decent layer of fresh. The salt water doesn't want to mix with the fresh due to the density gradient, and just sits there on the bottom. If there is any mud or detritus on the bottom of the lake, the microbial action tends to use up the available oxygen pretty quick in the bottom layer. The way to find out (without an oxygen probe) would be to put a livie on the bottom and another next to it under a float and see what happens (assuming the one under the float can survive in the fresh), as the top layer generally has oxygen in it because it is exposed to the atmosphere. After these rains there will probably be a few fish kills because of density gradient effects in SE QLD, especially in man made lakes with poor flushing.

[nathank]

yeah spot on ben, livies died on the bottom and lived on the top mate.. confirmed my suspicions.