Implications of Climate Change for SSSIs and other Protected Areas (Technical Paper 4)

Sites of special scientific interest (SSSIs) cover just under 7% of England, around 12 % of Wales and around 13 % of Scotland. In recent years, investments have been made to bring the habitats and species that SSSIs were designated for into ‘favourable’ condition. However, some SSSIs and other protected areas (PAs) are under direct physical threat from inundation following sea level rise, and changes in climate will affect the species and habitats that are present on most PAs. This report summarises these threats and considers options for changing the way that the protected area network is managed. The following impacts of climate change have already been detected on PAs; Saltmarshes have been lost to coastal squeeze, and coastal freshwater habitats including grazing marsh and lowland raised bog are at risk of inundation by seawater under current conditions Northern species have decreased in density, whilst southern species have increased in density. Whilst most evidence for this occurring on PAs comes from outside the UK, there is evidence that these patterns are occurring within the UK as well Southern species in the UK have used PAs to facilitate their northwards expansion In addition, the following impacts of climate change have been predicted to occur in future; The composition of flora and fauna on each PA will change – high confidence (medium evidence, high agreement) Cold adapted species of high latitudes and altitudes will tend to decrease on PAs, whilst warm adapted species will tend to increase – medium confidence (medium evidence, medium agreement ) PAs in the North of the UK will gain plant species overall, whilst PAs in the south are likely to lose plant species. This pattern is reversed for UK breeding birds – low confidence (medium evidence, low agreement) Species with lower dispersal capacities and those for which urban areas are a barrier to dispersal will be unable to colonize PAs that become climatically suitable – low confidence (limited evidence, medium agreement) Work in Africa predicted that some Important Bird Areas (IBAs) may lose all the species for which they were designated by 2085, although for around 90 % of species at least one currently occupied IBA should remain suitable. In Europe, species turnover is predicted to be faster than in Africa – medium confidence (medium evidence, medium agreement) Increasing range mismatching of interacting species, such as butterflies and their host plants, might mean that more management is necessary on PAs to preserve species that interact with each other – low confidence (limited evidence, medium agreement) Hotspots of bird diversity in Finland and Norway may no longer coincide geographically with PA boundaries – low confidence (limited evidence, medium agreement) Integrating consideration of climate change into management plans for the PA network is likely to result in more effective (and cost-effective) conservation solutions. In order to facilitate this integration, monitoring of climate change impacts and management actions should be carried out to enable adaptive decision making

The historic peat record: Implications for the restoration of blanket bog.

Peaty soils such as those found in blanket bogs lay down a history of their vegetation composition, along with the relative humification of these remains, which can be used to reconstruct bog surface wetness. These records highlight the variability of vegetation cover over time at blanket bog sites and could therefore be used to provide context to inform targets for the outcome of any restoration work. Because the vegetation present currently or in the recent past on the surface of a bog might be due to a relatively recent change, a longer-term history would give a different baseline to aim for. This should be relatively easy to achieve at some level for sites that have had cores taken, for which a database already exists. Historical records show a general picture of natural cycles in peat wetness and vegetation cover, and highlight a large level of variability that is sometimes found over even quite small areas in the timing of peat initiation and the types of vegetation present. This local variability suggests that topography (which varies more within a small spatial extent than climate or edaphic conditions) is a strong determinant of peat growth. However, climatic factors are also important. At some sites, past recovery of Sphagnum has been associated with wetter, cooler phases in the climate. Because rainfall and temperature are likely to change in future with continued climatic change, reconstructed climatic conditions at blanket peat sites could be used to determine whether the projected future climatic conditions at a potential restoration site are likely to fall within the range that supported peat formation in the past. This would help determine whether any restoration work has a chance of succeeding in the long term, and a database of sediment cores has been assembled for England that could be used as a starting point for this. One potential management strategy would be to accept that some vegetation that is currently considered undesirable has been present on blanket bogs in the past, and allow enough time and space for natural cycles to occur. However, what is not known is how much space would be needed to allow such natural cycles to continue, which sites are undergoing change as part of a natural cycle and which are not, or whether these natural cycles might be expected to continue in the same way in the future under climate change. There is some evidence for human impacts on blanket bogs in the past; the use of marginal lands for grazing and agriculture appear to have stopped the spread of peat in some areas, and in some other areas deforestation by humans appears to have been instrumental in initiating peat production. This demonstrates that there is considerable potential for management actions to impact the character of blanket bogs – based on inductive reasoning it seems likely that the reversal of some negative factors (such as blocking drains and removing plantation forestry) will result in the restoration of hydrological function, which could drive further changes in vegetation away from dry heath and trees to Sphagnum-dominated blanket bog that actively forms peat. However, care should be taken when choosing species to re-vegetate bare peat, since Calluna is associated with drier areas. What is not currently known is whether this is a cause or effect of drier conditions, but it is possible that the introduction of Calluna to the bog surface might result in drying of the peat, which would slow the rate of peat formation. Sphagnum is associated with lower emissions of methane and is a main peat forming species, so its suitability for re-vegetating bare peat is likely to be higher if it can become established. The timing of the initiation of erosion at some sites is well before the nitrogen deposition that is often implicated in this, and erosion has not always been caused by human activity. Indeed, some bogs have switched between erosion and accumulation over time, and others have recovered naturally from human impacts. However, what makes some bogs more resilient than others or causes the switch between erosion and accumulation is not known, and further research here would be beneficial to inform restoration management

A method for computing hourly, historical, terrain-corrected microclimate anywhere on Earth

1. Microclimates are the thermal and hydric environments organisms actually experience and estimates of them are increasingly needed in environmental research. The availability of global weather and terrain data sets, together with increasingly sophisticated microclimate modelling tools, makes the prospect of a global, web-based microclimate estimation procedure feasible. 2. We have developed such an approach for the R programming environment which integrates existing R packages for obtaining terrain and sub-daily atmospheric forcing data (elevatr and RNCEP), and two complementary microclimate modelling packages (NicheMapR and microclima). The procedure can be used to generate NicheMapR’s hourly time series outputs of above and below ground conditions, including convective and radiative environments, soil temperature, soil moisture and snow cover, for a single point, using microclima to account for local topographic and vegetation effects. Alternatively, it can use microclima to produce high-resolution grids of near-surface temperatures, using NicheMapR to derive calibration coefficients normally obtained from experimental data. 3. We validate this integrated approach against a series of microclimate observations used previously in the tests of the respective models and show equivalent performance. 4. It is thus now feasible to produce realistic estimates of microclimate at fine (<30 m) spatial and temporal scales anywhere on earth, from 1957 to present

A desk review of the ecology of heather beetle

The heather beetle Lochmaea suturalis is a naturally occurring species in the heather dominated landscapes of the United Kingdom. When the heather beetle population density increases dramatically it can cause significant damage to heather plants. It has been suggested that burning heather outside the permitted heather-burning season will promote the regeneration of heather following heather beetle damage. There is also some discussion as to whether burning outside the permitted season might also help control heather beetle. For these reasons Natural England regularly receives applications for licences to burn outside the permitted season. However, burning at this time of year may have effects on a wide range of biodiversity. Therefore, Natural England commissioned this report, and (NEER009 - Desk review of burning and other management options for the control for heather beetle) to ensure the best available evidence is being used. This report is based on an extensive literature review to determine the current state of knowledge of the ecology of the heather beetle. Some of the older references, which appear to form the basis for much current thinking on the subject, are now out of print and were not accessible for this review. A flurry of work was published in the 1980s and early 1990s, but much of this was either: • based at the same experimental plots; • involved relatively low levels of replication; or • did not report heather beetle damage as a central focus of the work. More recently, there have been some PhDs quantifying the ecology of heather beetles in more detail, but these have rarely been published in the peer-reviewed literature. Therefore, current thinking may be influenced by out-of-date information and experimental work that does not truly back up the conclusions of authors. This makes it difficult both to confidently discern patterns over time in frequency and severity of attacks (such as might be caused by climate change or changing nutrient deposition loads) and to be certain which factors control population levels in most year’s at most heather-dominated sites. Much more, and higher quality, monitoring and experimental work needs to be carried out to be able to predict the likely population dynamics of this species under different scenarios. The potential for parasites and parasitoids to control population numbers is particularly worthwhile. More detailed spatial analyses based on citizen science records, combined with carefully designed laboratory studies, might also be used to more clearly elucidate the relationship between beetle numbers and climatic conditions, enabling prediction of the relative likelihood of outbreaks occurring in the future

Desk review of burning and other management options for the control for heather beetle (NEER009)

The heather beetle Lochmaea suturalis is a naturally occurring species in the heather dominated landscapes of the United Kingdom. When the heather beetle population density increases dramatically it can cause significant damage to heather plants. It has been suggested that burning heather outside the permitted heather-burning season will promote the regeneration of heather following heather beetle damage. There is also some discussion as to whether burning outside the permitted season might also help control heather beetle. For these reasons Natural England regularly receives applications for licences to burn outside the permitted season. However, burning at this time of year may have effects on a wide range of biodiversity. Therefore, Natural England commissioned this report, and (NEER008 - A desk review of the ecology of heather beetle) to ensure the best available evidence is being used. An extensive literature review was carried out to determine the effectiveness of burning and other management options in managing heather-dominated systems for the heather beetle Lochmaea suturalis. In general, the quantity of relevant studies was low, and the quality of most was also poor, with very low levels of replication and/or a lack of controls or comparators being very common. There are three potential ways that management could be used. The first way is to reduce the likelihood of outbreaks. There is currently no evidence that burning is useful for this, due to a lack of relevant studies. Other management options that could be considered to achieve this are biological control and drainage of wetter areas, as well as general moorland management such as mowing, rotovating and sod cutting. The second way that burning could be used is by burning infested areas to reduce the numbers of heather beetles present. There has been some discussion as to whether it would be necessary to do this outside the current burning season, but there is currently no reliable evidence available to show whether this is effective, nor a cost-benefit analysis to take account of the additional risks of burning during the summer months. This is again due to a total lack of relevant studies. Other management options at this stage are to use insecticides on the affected areas, but there are also risks associated with this and again there is a lack of evidence as to how effective it would be. The potential for biocontrol at this stage has also not yet been explored. The third way is in encouraging regeneration of damaged areas. The available evidence for this is generally poor quality, and there is some suggestion that management techniques other than burning might be more effective at encouraging regrowth. In addition, some sites have been observed to regenerate naturally, in the absence of management, so there is a question as to whether management is necessary. Some trials are currently under way in Scotland and the Peak District with the aim of determining which management techniques are best for restoring damaged heather, but again the level of replication and lack of control areas appears to be a problem. The following are recommended in order to be better able to advise managers in the future: • Management actions should be carefully monitored so as to establish the effects of decisions (including whether to burn out of season or not). This monitoring should use properly designed experiments with adequate levels of replication and control plots. The effectiveness of management in controlling heather beetles and the effects on biodiversity as a whole and on ecosystem functioning should all be recorded. • Further research should be undertaken into the relationship between the heather beetle and its natural enemies. • Further research should be undertaken into the other factors that might affect the likelihood of outbreaks occurring

Integrating an individual-based model with approximate Bayesian computation to predict the invasion of a freshwater fish provides insights into dispersal and range expansion dynamics

Short-distance dispersal enables introduced alien species to colonise and invade local habitats following their initial introduction, but is often poorly understood for many freshwater taxa. Knowledge gaps in range expansion of alien species can be overcome using predictive approaches such as individual based models (IBMs), especially if predictions can be improved through fitting to empirical data, but this can be challenging for models having multiple parameters. We therefore estimated the parameters of a model implemented in the RangeShifter IBM platform by approximate Bayesian computation (ABC) in order to predict the further invasion of a lowland river (Great Ouse, England) by a small-bodied invasive fish (bitterling Rhodeus sericeus). Prior estimates for parameters were obtained from the literature and expert opinion. Model fitting was conducted using a time-series (1983 to 2018) of sampling data at fixed locations and revealed that for 5 of 11 model parameters, the posterior distributions differed markedly from prior assumptions. In particular, sub-adult maximum emigration probability was substantially higher in the posteriors than priors. Simulations of bitterling range expansion predicted that following detection in 1984, their early expansion involved a relatively high population growth rate that stabilised after five years. The pattern of bitterling patch occupancy was sigmoidal, with 20 % of the catchment occupied after 20 years, increasing to 80 % after 30 years. Predictions were then for 95 % occupancy after 69 years. The development of this IBM thus successfully simulated the range expansion dynamics of this small-bodied invasive fish, with ABC improving the simulation precision. This combined methodology also highlighted that sub-adult dispersal was more likely to contribute to the rapid colonisation rate than expert opinion suggested. These results emphasise the importance of time-series data for refining IBM parameters generally and increasing our understanding of dispersal behaviour and range expansion dynamics specifically

Influence of environmental and biological factors on the overwinter growth rate of Atlantic salmon Salmo salar parr in a UK chalk stream

Smolt lengths are increasingly recognised as an important determinant of salmonid marine survival rates. Overwintering growth rates could thus strongly influence adult return rates. In Atlantic salmon Salmo salar, most overwintering studies focus on rivers in harsh climates with minimal growth, yet in more southerly rivers, overwintering growth rates can be relatively high. Here, the factors influencing annual overwinter growth rates were tested for juvenile S. salar in a temperate chalk stream in southern England over 13 years, where over 10,000 salmon parr were tagged annually in autumn and a proportion recaptured the following spring during smolt emigration. Winters of higher and more variable water temperatures, with longer periods of high flows, showed increased overwintering growth rates. Faster growth rates were recorded from sites further upstream and that had lower parr densities; smaller individuals also grew more than expected for their initial size. These results suggest that a range of factors influences overwintering salmonid growth rates and can be used to inform management decisions to maximise the quality of emigrating smolts

Diversifying environmental volunteers by engaging with online communities

Environmental volunteering can benefit participants and nature through improving physical and mental well‐being while encouraging environmental stewardship. To enhance achievement of these outcomes, conservation organizations need to reach different groups of people to increase participation in environmental volunteering. This paper explores what engages communities searching online for environmental volunteering. We conducted a literature review of 1,032 papers to determine key factors fostering participation by existing volunteers in environmental projects. We found that the most important factor was to tailor projects to the motivations of participants. Also important were promoting projects to people with relevant interests, meeting the perceived benefits of volunteers and removing barriers to participation. We then assessed the composition and factors fostering participation of the NatureVolunteers's online community (n = 2,216) of potential environmental volunteers and compared findings with those from the literature review. We asked whether projects advertised by conservation organizations meet the motivations and interests of this online community. Using Facebook insights and Google Analytics we found that the online community were on average younger than extant communities observed in studies of environmental volunteering. Their motivations were also different as they were more interested in physical activity and using skills and less in social factors. They also exhibited preferences for projects which are outdoor based, and which offer close contact with wildlife. Finally, we found that the online community showed a stronger preference for habitat improvement projects over those involving species survey‐based citizen science. Our results demonstrate mismatches between what our online community are looking for and what is advertised by conservation organizations. The online community are looking for projects which are more solitary, more physically active and more accessible by the organized transport. We discuss how our results may be used by conservation organizations to better engage with more people searching for environmental volunteering opportunities online. We conclude that there is a pool of young people attracted to environmental volunteering projects whose interests are different to those of current volunteers. If conservation organizations can develop projects that meet these interests, they can engage larger and more diverse communities in nature volunteering

Changing cultures, changing environments: A novel means of investigating the effects of introducing non-native species into past ecosystems

Descended from junglefowl of Asia and South-east Asia, the chicken was introduced into Europe during the first millennium BCE. As one of the most recently domesticated species, it makes an excellent case study for investigating the consequences of such introductions to past ecological communities. We present a unique application of a novel ecological method to explore multiple past interspecies relationships. Analysing the faunal record using a Bayesian belief network, which allows for the analysis of multiple interspecies relationships simultaneously, indicates that the chicken has more affinity with other domestic birds rather than domestic mammals in terms of species interactions. We find that the introduction of the chicken affected fox, partridge, pigeon and rat, but the success of the chicken was most affected by responses to abiotic variables, rather than biotic interactions. As the method is not limited to environmental variables, we also examined the effect of recovery method and demonstrate that sieving would enhance the frequency of small animal remains recovered from archaeological sites