However, the legal open season for brown trout fishing on most rivers and lakes begins some time in March. There are one or two catchments with a February opening date, but most trout fly fishermen start to emerge from hibernation this month.
The reason for this is trout spawn in mid- winter and this is a very debilitating process which leaves them thin and out of condition. It takes them until early spring to recover and in many waters they won’t be back in peak condition until some time in May.
Nowadays there are several different species of trout in Ireland, particularly in smaller still-waters that are stocked with American rainbow trout or various exotic hybrids. However, the brown trout is the only native species, apart from sea trout — and sea trout, often called white trout, are only brown trout that have spent their lives in salt water.
Brown trout are an important resource for anglers and for the tourist industry so they’ve been intensively studied everywhere they occur naturally or have been introduced — and they’ve been introduced into every continent except Antarctica.
Irish fishery scientists have played an internationally significant part in increasing our knowledge of the biology of this fish. In the middle of the last century Dr W Frost and Dr M Brown published a groundbreaking monograph called The Natural History of the Brown Trout in the British Isles’.
It established the relationship between the amount of calcium dissolved in the water, and therefore its alkalinity, and the growth rate of trout. Most of the field work was carried out on the River Liffey. Trout were caught on the fly rod at Ballysmuttan in Co Wicklow, where the water is acid and there’s little calcium present, and compared to trout caught in the calcium rich waters at Straffan in Co Kildare.
The two scientists always published their work, whether it was scientific papers or books for the general public, using an initial not a first name. This is because the W stood for Winifred and the M for Margaret and at that time there was still considerable prejudice, at least among the scientific community, against research done by women.
This was particularly the case when the field work involved wading up a river and catching trout on a fly rod. It was felt that this was an unsuitable thing for a lady to do.
So two of the great pioneers of Irish field studies who contributed enormously to the sum of knowledge that the modern trout angler draws on today, concealed their identities. And they did it so efficiently that few of the anglers returning to our rivers and lakes this month have ever even heard of them.
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