The updated Solent bass series is attached. The 2011 survey takes the year class index only as far as 2009 as the youngest age class we use is 2-year-olds. As there was no survey in 2010, the indices for the 2008 and 2009 year classes are based on only one annual survey and only one age class compared to two surveys with three age classes each in many ofthe earlier years. As there was no May-July survey in 2010 and 2011 we also calculated an index for September surveys only. This gives relatively larger indices over the early 2000s compared with the combined May-July & sept surveys, but the general trends are similar.
The Solent Survey is (as far as we are aware) pretty much the best time series of data we have in the UK that monitors the success or otherwise of bass recruitment. BASS is very worried by what it is showing; i.e. reducing numbers of adult bass spawning, and survivability issues over the very cold winters (or a combination of the two), leading to very low numbers of juvenile bass. And this is without any data which will show cold winter impacts on the 2010 and 2011 spawning.
BASS is pushing for these surveys to carry on – 2012 will give us the first look at the 2010 year group after 2 winters, plus a better look at 2008 and 2009 after the severe winters.
Link to Survey data: Cefas Updated Solent Bass Survey