There are 91 per cent less sardines now then last year, could this be a bad sign for the ocean?

It is a blatant attempt by the denier sardines to even up the numbers.

97% of all sardines were global warming alarmists and 3% were not. Now the numbers are 66% of sardines are believers an 33% are not. This is all part of the denier push to get things evened out by the time of the Paris Conference where they will all be packed in like, er, sardines.

Sardine populations vary due to their natural cycles. If human activity is a contributing cause then it is through over-fishing, but that is disputed. There is no indication that the warming oceans (per your putting your question in this section) caused the current decline. If the populations don't recover as heartily as in the past then we need to consider human activity, Right now there is nothing outside of natural cycles apparent in sardine population.

Possibly, though you shouldn't read too much into year-to-year changes. Look at 5-year or 10-year trends, at a minimum.

And, for fish, declining stocks are more likely to be due to overfishing than global warming or ocean acidification. Shellfish stocks are heavily affected by ocean acidification, and both acidification and warming affect corals, but I think small fish like sardines are less affected by either.

Fish stocks rise and fall and fish migrate you really can't make a broad statement covering ALL the oceans of the world ( 375 million square Km) and expect people to believe your quote of 91%

The Ocean's probably smell a lot better.

Two years is much too short a time period to discern a climactic trend. I highly doubt it has anything to do with global warming or climate change. (As that is the category this is in now)

Just because you can't count them, doesn't mean they're not there.

Yes..... The honey bees are declining also........

yes, but why is this in the horoscopes lol...

No