Daunt, Francis. 2016. Do early warning indicators consistently predict nonlinear change in longterm ecological data? Journal of Applied Ecology, 53 (3). 666-676. 10.1111/1365-2664.12519 Contact CEH NORA team at noraceh@ceh.ac.ukThe NERC and CEH trademarks and logos ('the Trademarks') are registered trademarks of NERC in the UK and other countries, and may not be used without the prior written consent of the Trademark owner.Page | 1 2. We tested whether long term abundance time series of 55 taxa (126 data sets) across multiple 34 trophic levels in marine and freshwater ecosystems showed: i) significant non-linear change in 35 abundance ("turning points") and ii) significant increases in variance and autocorrelation 36 ("EWIs"). For each data set we then quantified the prevalence of three cases: true positives 37 (EWI and associated turning point), false negatives (turning point but no associated EWI) and 38 false positives (EWI but no turning point).

Although the ferox of Scottish Highland lochs (lakes) have long captured the interest of both laymen and scientists, no previous investigation of their biology or ecology has been undertaken. This paper is based on 141 ferox from 22 lochs collected during the last 22 years and the results from a recent investigation into their status and distribution. When the features of their environment and the distribution of what is apparently their main food source, the arctic charr, were investigated, two essential conditions governing the occurrence of ferox emerged and a third appeared to be important: (i) oligotrophic waters; (ii) the presence of charr and (iii) a large loch (over 100 ha in extent). Typically, ferox grow slowly during the first third of life but on reaching what may be a critical length enter into a phase of rapid growth and may eventually reach a size and age very much greater than that of the individuals in the normal trout population from which they arise. This pattern of growth contrasts markedy with that of large, fast growing brown trout from eutrophic waters in Scotland which do not reach the same extremes of age or size.

This paper is based on the investigation of 173 lochs in Scotland from which a total of over 4700 brown trout were examined. Twenty-four of the lochs, all in northern Scotland, and their trout populations, were sclected for detailed comparison in an attempt lo identify environmental factors that might affect the growth rate of trout. The lochs probably represented the full range of main standing water habitats in the region-ranging from a saline loch in the Outer Hebrides to one in a sub-arctic environment high on the Cairngorm plateau in the Central Highlands. The study indicates that for practical purposes the growth rate of trout is negatively correlated with population density. Some suggestions for improving brown trout lochs, based on the findings of this paper, are included.

. (2013) 'Reduced ow impacts salmonid smolt emigration in a river with low-head weirs.', Science of the total environment., 458-460 . pp. 435-443. Further information on publisher's website:http://dx.doi.org/10.1016/j.scitotenv.2013.04.063Publisher's copyright statement: NOTICE: this is the author's version of a work that was accepted for publication in Science of The Total Environment. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reected in this document. Changes may have been made to this work since it was submitted for publication. A denitive version was subsequently published in Science of The Total Environment, 458-460, August 2013458-460, August , 10.1016458-460, August /j.scitotenv.2013 Additional information: Use policyThe full-text may be used and/or reproduced, and given to third parties in any format or medium, without prior permission or charge, for personal research or study, educational, or not-for-prot purposes provided that:• a full bibliographic reference is made to the original source • a link is made to the metadata record in DRO • the full-text is not changed in any way The full-text must not be sold in any format or medium without the formal permission of the copyright holders.Please consult the full DRO policy for further details. to increasing flow at a faster rate than smolts in 2011. This is the first study to demonstrate river 31 flow impacts on the migration success of wild salmonid smolts at small weirs. Because small weirs 32 are common in rivers and because spring-summer low flow periods may become more frequent with 33 climate change (based on UKCIP09 models) and altered river hydrology, further research and 34 improved management is needed to reduce the impacts of low river flows in combination with low-35 head weirs on salmonid smolt migration. 36

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