Chalkstream salmon: Test and Itchen salmon runs in 2015 are encouraging but many challenges remain to reach abundance.

The Environment Agency’s Test and Itchen salmon counters have recorded the largest runs of returning salmon since consistent records began in 1990

The Environment Agency's Test and Itchen salmon counters have recorded the largest runs of returning salmon since consistent records began in 1990. The estimates for the Test and Itchen for 1 May -31 December were 2,007 and 903 respectively. The Test's previous best was 1,487 in 2008 and the Itchen's previous best was 779 in 2010.

The 2015 runs are a big improvement on the worst year in the last 25 years, 1991, when approximately 400 and 50 fish ran the Test and Itchen respectively. However, these record runs are well down on long-term history when runs were probably over 5,000 on the Test and 2,500 on the Itchen judging from catch statistics.

So what is behind the leap in the numbers? We do not know why this year is so much better than the recent past and, as the graph in the EA briefing document shows, the annual counts are volatile.

And, although the trend in salmon numbers is positive, there is no room for complacency, especially as we now know from genetic work that southern chalkstream salmon are distinct from any other UK or European salmon stocks, and so it is vital that are properly protected. The Test and the Itchen face formidable threats from abstraction, sedimentation, nutrient enrichment and, to a lesser extent, organic pollution. All these work against the fish, and must be addressed as a matter of urgency if we are to ensure the continuation of these unique salmon.

Salmon & Trout Conservation UK will not let up on its goal to see rivers achieving "good ecological" status." We are working hard to help deliver a river and estuarine environment in which salmon runs can improve on these (and other) rivers. Our Riverfly Census is highlighting ecological threats which need to be tackled and we are heavily involved in seeking to curb abstraction. Any help you can give us to protect our salmon, of which the chalkstream fish are an extremely rare group, will not be wasted.