WTT Blog - Tagged with climate change

Goldilocks weather

Posted on September 03, 2018

Goldilocks weather

What has happened to our young trout during all the recent 'abnormal' weather? It's a question I have heard discussed and been asked directly quite regularly of late, and I intend to post a response with a relatively local flavour, here on the blog, in the not too distant future. However, to pre empt that, I thought I would post some thoughts from my colleague in the south, Andy Thomas. Glaciers were still retreating from Cumbria when Andy first started working on rivers, so he's seen a thing or two....

Please note that this article was originally published in the WTT Summer Newsletter (one of the perks of being a member), and hence was written prior to the extended warm & dry period that subsequently ensued! 

Low flows and salmonid rivers: an update

Posted on July 14, 2017

Low flows and salmonid rivers: an update

Jess Picken was the first to contribute to our new series of guest blogs in which she outlined plans for her PhD. And clearly, she has been busy! She is back with an update already...

To recap on my previous post, numerous studies have reported that low flow reduces the density of salmonids within streams. What is not so well-known is what, or how, other parts of the salmonids’ ecosystem are also affected by low flow. Riverflies and other aquatic macroinvertebrates make up a large proportion of juvenile salmonid diet, which is subsequently reflected in salmonid growth rate, condition and survival. Understanding how the availability of these macroinvertebrates changes with reduced summer flow is important to help conserve fish species of high UK and European importance.

My life at the moment... macroinvertebrates down the microscope!

Impacts of low flows on salmonid river ecosystems

Posted on March 22, 2017

Impacts of low flows on salmonid river ecosystems

In the first of a new series from students actively involved in research relevant to wild trout, Jessica Picken from Queen Mary University of London summarises the aims of her PhD working with the Game & Wildlife Conservation Trust and with CEFAS.

Climate change is considered to be the most critical disturbance imposed on natural systems on a global scale. Climate models predict that average temperatures in the UK will increase over the course of the next 50 years with the greatest warming in the south of England during summer months, and that annual average precipitation will reduce. However, the reduction in precipitation is expected to be more pronounced during summer than winter, whereas extreme winter precipitation is expected to become more frequent. In other words, there is likely to be an overall shift towards drier summers but wetter winters.

Coping with climate change

Posted on June 02, 2016

Coping with climate change

After the winter spates and ‘unprecedented’ flows rearranged much of the substrate of my local river, the Aire in N Yorkshire, there has been virtually no rain since. Consequently, it is already at late summer level, and the lack of energy has allowed thick scums of bacteria and other microbes to develop on the bed. The lethargy of some of the trout seems to reflect that of the river. And the forecast is for a hot summer, allegedly.

This leads me to my monthly scan of the literature for research involving brown trout, which has thrown up two recent papers assessing impacts of climate change via modelling. The first was a study of trout populations from two streams on the Iberian Peninsula, where trout are at the edge of their natural distribution. Ben Tyser reported for WTT on earlier work in this region – see the WTT Library (Articles by topic) page on Climate Change: Iberian trout threatened by climate change.