Ne'er cast a clout 'til May be out

This old saying is usually applied to the coming of summer. Many assume it means don't throw away your winter clothes until the month of May is over. Old wives' tales suggest it refers to the appearance of the new hawthorn blossom (or 'May' flower) the appearance of which is the true mark of the beginning of summer. This year has seen butterflies out early and plants recovering from April frost and snow. I was delighted to receive an invitation to fish on the River Test but soon realised that in April this would prove a challenge. And so it proved to be. This was no 'duffer's fortnight,' when the mayfly (Ephemeroptera) turn trout in the river into kamikaze pilots attacking every fly on the water, whether real or imitation, until they are sated or dispatched.

A hierarchical model for salmon run reconstruction and application to the Bristol Bay sockeye salmon (Oncorhynchus nerka) fishery

The goal of spreading the annual catch of a Pacific salmon (Oncorhynchus spp.) run proportionally across all segments of the migration is rendered difficult or impossible because of the interannual variability in both run size and run timing. This problem is particularly acute in the case of the fishery for sockeye salmon (Oncorhynchus nerka) in Bristol Bay, Alaska, for which traditional run reconstruction models are not applicable because of the extreme temporal compression of the run. We develop a run reconstruction model appropriate for sockeye salmon in Bristol Bay by accounting for the hierarchical structure of the problem and by including process error. Our results indicate that the hierarchical structure is, in fact, not necessary, whereas the process error parameters are needed to fit the data. We suggest further model development without the hierarchical structure, including incorporating in-river test fishing data. The results of our method can be used to address questions regarding environmental or intrinsic drivers of run timing and the possibility of artificial selection on run timing.