Not just a euphemism for a false trail, but a kind of smoked herring that has probably served as a euphemism for a false trail since at least the C16th
On the rise and demise of ring net fishing for herring, which originated in the waters of Loch Fyne and played a role in the sad development of overfishing
An 8,000 year history of salt and salt pickling, paying particular attention to the preservation of herrings by the German Hanse, the Dutch and the British.