My take on these milky white flesh snapper.
Firstly lets look at what appears the normal pattern for snapper. Come spring,rapidly increasing day length, ( just as important as temperature imo), water just beginning to slightly warm and the Hauraki gulf begins to fill up with pre spawn snapper ,from far and wide.From early october ,november ,into part of december , spawning. A few thin fish at this time,but dosent last too long as fish ,with full on metabolism begin to recover quickly. Then many move in close ,feeding up ,putting on fat, before moving out late autumn. We have all seen those fish with even the gut covered in fat layers. Day length decreases ,water cools ,and metabolism slows. The fat gets them through the winter.
La Nina. Warmer surface waters .3 years of this cycle,which has just ended and coincides with these thin white flesh snapper.
Lets back track to October 2020. Beautiful ,bright orange ,well conditioned fish. Well fed,gut full of food. The pre spawn feed up. Even very early October some snapper i caught were on the verge of spawning . Early.?
Fast forward to 5th January 2021. Two of us went out for a fish,6-7 metre, inner gulf. Tucked away in a quiet bay away from the crowds. Managed 11 snapper from low 30s to low 40cms. All in good condition.
These were almost certainly early spawners ,well recovered and on the feed. I always check stomach contents. All were full of shell fish ,shells and crab. .
It was then i noticed something unusual,something i had not seen before. Most of these fish had very small,fully intact, developing roe/ milt. My first thought was, these fish are going to do a second spawn.
At a guess ,judging by the roe /milt size these fish would have spawned mid to late autumn,possibly early winter
Rapidly decreasing day length,cooling water temperature, after spawning these fish would go into winter as thin ,wasted ,spent fish.
With metabolism slowing, slower movement ,slower digestion and slower ability to feed these fish would not be able to put on weight or fat during winter. And even when spring came it would be a long feed time before they returned to normal condition.
Given many of these milky white flesh fish are caught in open waters ,close to spawning grounds,could a second spawn for some, (but not all) , of the bio mass be the reason.
3 years of this ,coincides with 3 years of La Nina weather . Coincidence.?
Now with El Nino officially just setting in, hopefully cooler surface waters, could we see a return to normal cycles and the end of these fish. Only time will tell.