Solent Disturbance and Mitigation Project Phase II: Predicting the impact of human disturbance on overwintering birds in the Solent.

The Solent coastline provides feeding grounds for internationally protected populations of overwintering waders and wildfowl, and is also extensively used for recreation. In response to concerns over the impact of recreational pressure on birds within protected areas in the Solent, the Solent Forum initiated the Solent Disturbance and Mitigation Project to determine visitor access patterns around the coast and how their activities may influence the birds. The project has been divided into two phases. Phase I collated and reviewed information on housing, human activities and birds around the Solent, and reviewed the potential impact of disturbance on birds. Phase II has involved a programme of major new data collection to (i) estimate visitor rates to the coast from current and future housing, (ii) measure the activities and distances moved by people on the shore and intertidal habitats, and (iii) measure the distances and time for which different bird species respond to different activities. The current report represents the culmination of Phase II, in which the primary data are used to predict whether disturbance may be reducing the survival of birds. Predictions are derived for wader species by developing detailed computer models of birds and disturbance within Southampton Water and Chichester Harbour. These models create a virtual environment within the computer incorporating the intertidal invertebrate food supply of the birds, the exposure and covering of this food through the tidal cycle, disturbance from human activities, and the energy requirements and behaviour of the birds as they avoid humans and search for food. The invertebrate food supply of birds in the models was derived from previous intertidal surveys, and the exposure of intertidal habitat predicted from a tidal model of the Solent. The models incorporate the costs that birds incur when avoiding human activities (e.g. increased density in non-disturbed areas, reduced time for feeding and increased energy demands when flying away), but also their abilities to compensate for these costs (e.g. by feeding for longer or avoiding more disturbed areas). The predictions indicate how disturbance may be effecting the survival of waders throughout the Solent. The following waders were included in the models: Dunlin Calidris alpina, Ringed Plover Charadrius hiaticula, Redshank Tringa totanus, Grey Plover Pluvialis squatarola, Black-tailed Godwit Limosa limosa, Bar-tailed Godwit Limosa lapponica (Chichester Harbour model only), Oystercatcher Haematopus ostralegus and Curlew Numenius arquata. A simpler approach was used to assess how disturbance may be effecting Brent Geese in the Solent. As with any models, the predictions of the models used in this project depend on the data with which they are parameterised and the assumptions they make about the real system. The current and future visitor rates used in the models were themselves predicted using statistical analyses of household survey and on-site visitor data. The responses of birds to disturbance were parameterised using on-site observations of the responses of birds to disturbance. Furthermore, models are a simplification of real systems, and it is important to recognise this when interpreting their predictions. The report considers how the model parameters and assumptions may influence predictions. These include: (i) the way in which the disturbance data were measured and assumptions made about how birds and people are distributed in space and time; (ii) the way in which the behaviour of birds to disturbance differs between sites; (iii) the effect of extreme weather on the birds; (iv) how rare or localised activities are incorporated into the models; and (v) how consumption of food by species other than waders is included. The project predicted changes in visitor numbers to the Solent coast. Local authorities in the Solent region provided projections of future housing developments in the region. These were combined with data on visitor rates to different parts of the coast and the distance travelled to visit the coast, to predict coastal visitor rates with current and future housing. Using current housing levels, 52 million household visits per year to the Solent coast were predicted (i.e. the shore from Hurst Castle to Chichester Harbour, including the north shore of the Isle of Wight). Using the housing data provided by local authorities, visitor numbers were predicted to rise by around 8 million household visits, to a total of 60 million, an overall increase of 15%. Within Chichester Harbour, the food supply surveyed was not predicted to be able to support the majority of wading birds modelled. This implied that either the invertebrate survey underestimated the intertidal food supply, or that other food was available either terrestrially, or from neighbouring intertidal sites such as Langstone Harbour. Similar invertebrate surveys have been used to parameterise 17 other similar models, and in all cases birds were predicted to have survival rates close to, or higher than those expected. Due to uncertainties with the Chichester Harbour invertebrate data, it was decided not to use the Chichester Harbour model to predict the effect of disturbance on the birds. However, it is important to note what the effect of low food abundance would be on the effect of disturbance on the birds. The impact of disturbance on survival and body condition will depend on the birds’ ability to compensate for lost feeding time and extra energy expenditure. Birds will be better able to compensate when more food is available, and so lower food abundance in a site will make it more likely that disturbance decreases survival and body condition. Within Southampton Water, in the absence of disturbance, all wader species modelled were predicted to have 100% survival and maintain their body masses at the target value throughout the course of winter. Disturbance from current housing was predicted to reduce the survival of Dunlin, Ringed Plover, Oystercatcher and Curlew. Increased visitor numbers as a result of future housing was predicted to further reduce the survival of Dunlin and Ringed Plover. Disturbance was predicted to have a relatively minor effect on the mean body mass of waders surviving to the end of winter, largely because the individuals with very low mass starved before the end of winter. The Southampton Water model provided evidence that current and future disturbance rates may reduce wader survival in this site. Hypothetical simulations were run to explore how intertidal habitat area, energy demands of the birds and the frequency of different activities may influence the survival of waders within Southampton Water. The survival rates of Dunlin, Ringed Plover, Oystercatcher and Curlew were predicted to be decreased by any reduction in intertidal habitat area (e.g. due to sea level rise) or increases in energy demands (e.g. due to disturbance at roosts or cold weather). Wader survival was predicted to increase if intertidal activities were moved to the shore. This meant that the disturbance from these activities was restricted to the top of the shore rather than the whole intertidal area, and so the proportion of intertidal habitat disturbed was reduced. Reductions in the number of dogs that were off leads were also predicted to increase the survival of some wader species. Removing bait digging from simulations did not increase wader survival. However, this happened because bait-digging was assumed to be a relatively infrequent activity. This does not mean that bait-digging could not adversely affect the birds if it occurs at a higher frequency, and the simulations did not incorporate the depletion of the invertebrate prey of the birds caused by bait digging, which would be an additional effect on the birds in addition to disturbance. Brent Geese were considered in the light of the Solent Waders and Brent Goose Strategy. Important issues are the size of individual sites, their spacing and the ease with which birds can move between the sites. A high proportion of each site needs to be further away from visitor access routes than the distances over which birds are disturbed to ensure that disturbance to the birds is minimised. This could be achieved through a network of larger sites or by preventing visitor access through, or close to, smaller sites. Both intertidal and terrestrial food resources are important to the birds, intertidal food typically being of higher food value but dying back and / or becoming depleted during the autumn / early winter. Previous models of Brent Geese have predicted that the loss of terrestrial habitat typically has the highest effect on survival, and so such habitat is predicted to be particularly important for the birds. Maintaining a suitable network of saltmarsh sites will be increasingly important as the total area of saltmarsh declines with sea level rise. The findings of the present project are in general support with the recommendations of the Solent Waders and Brent Goose Strategy. Predicted current visitor rates varied widely throughout the Solent, but were relatively high within Southampton Water. The highest percentage increases in visitor rates were on the Isle of Wight (50-75%). Wader survival was predicted to be decreased in Southampton Water when daily visitor rates to coastal sections were greater than 30 per ha of intertidal habitat. The potential impact of visitors on wader survival throughout the Solent was calculated by comparing visitor densities throughout the Solent (expressed relative to maximum intertidal habitat area) to the visitor densities predicted to decrease bird survival within Southampton Water. The intertidal food supply within Chichester Harbour was insufficient to support the model birds and so any disturbance (by reducing feeding area or time, or increasing energy demands) would have decreased predicted survival in this site. There is also doubt as to the food supply within the other harbours and so some caution is appropriate when applying the results from Southampton Water to these sites. Coastal sections with daily visitor rates over 30 per ha are identified. The predictions of the Southampton Water model suggest that birds within these sections may have reduced survival due to disturbance from visitors. Whether or not such visitor rates will reduce survival will depend on the food abundance in the coastal sections themselves as well as that in neighbouring sections. The area of overlap between an activity / development and the distribution of birds is often used as a measure of the impact of the activity on the birds, with 1% overlap often taken as the threshold for impact (note however that this 1% overlap does not necessarily mean that an activity will have an adverse effect on the survival or body condition of birds). Therefore, the percentage of intertidal habitat disturbed within each coastal section was calculated as an index of the potential impact of disturbance on the birds. Assuming the maximum intertidal area and only including intertidal visitors, over 50% of the area of many coastal sections was predicted to be disturbed, with an average of 42%

The Solent Disturbance & Mitigation Project Phase II – On-site visitor survey results from the Solent region

This report sets out the results of the on-site visitor survey component of the Solent Disturbance and Mitigation project. The work was commissioned by the Solent Forum in response to concerns over the impact of recreational pressure on features of the Solent SPA, SAC and Ramsar Sites. Of particular concern are the cumulative impacts of recreational use arising from potential new housing developments in the Chichester District and South Hampshire. The visitor surveys were conducted during the winter 2009/2010 to assess the level and type of visitor use at selected locations along the Solent coastline. Overall it is likely that the number of visitors interviewed and counted during the survey period was lower than would be normally be expected given the especially cold 2009/2010 winter. With that in mind, there is the potential that the monitoring could provide an underestimate of the absolute number visitors to the region. However, the interviews were designed to elicit generic and site specific details from visitors and although fewer individuals may have been recorded or interviewed because of the weather we can assume that the general winter visitation pattern remained similar and the results very useful in understanding who, where, when and why people use the coast. Counts of people and interviews were conducted at 20 locations around the Solent coastline (including the north shore of the Isle of Wight). A total of 16 hours of surveys were carried out at each location, split equally between weekend (8 hours) and a weekday (8 hours). A total of 784 interviews were conducted, accounting for 1,322 people and 550 dogs. The average group size was 1.7 people. There were differences in visitor numbers between survey locations, with the highest visitor numbers recorded at Emsworth (1088 visitors were recorded using the site over 16 hours) while Lymington (Boldre/Pylewell) was the least busy (33 visitors counted over 16 hours). Visitor numbers per day were typically highest on weekend compared to weekdays. Holiday makers accounted for 6% of the total number of visitors recorded (80 visitors). Visitors were undertook a wide range of activities, with walking (without a dog) and dog walking the two most frequently recorded activities (44% and 42% of interviews). Across all sites and activities, visits were typically short, with 89% lasting less than two hours. The main modes of transport used to reach sites were by car and on foot, with the proportion of people arriving by each mode varying between sites. Across all sites (and taking the data for non-holiday makers only), 51% of interviewees arrived by car and a further 46% arrived on foot. Home postcodes were used to identify the distance between interviewee’s home and the location where interviewed. Half of all visitors arriving on foot lived within 0.7km, while half of all visitors arriving by car lived more than 4km away. Only 9% of foot visitors lived more than 2km away compared to 80% of all car visitors. Linear regressions using housing numbers within different distance bands of a location as a predictor of visitor numbers for each location show a positive relationship between the number of houses within 1km, 3km and 5km and number of visitors entering each survey location. Car park capacity at the access points did not provide a good indication of the frequency of visitors arriving by car to each location. The relationship is more complex, future modelling of visitor rates travelling to locations by car should include potential road related parking (related to length of nearby roads around access points) in addition to official and off road car parking capacity around the access points. 2 Route data were also collected for each interview, with lines drawn directly on maps during the survey. These route data were analysed to determine which activities take place below Mean High Water Mark (MHWM) and how far different groups go out into the intertidal. Across all the interviews, 7% of the mapped routes did not go within 25m of MHWM and were therefore visitors who did not actually make it to the beach (in some locations the survey point was set inland, for example near to parking locations etc.). A further 78% were entirely within the band between 25m above and 25m below MHWM, indicating routes that remained at the top of the beach, on the seawall or similar. It was 14% of the mapped routes that went below 50m from MHWM, and these included a range of activities, for example bait diggers, dog walkers, joggers, cyclists and people out on a family outing. The implications of the results for further modelling and in relation to the disturbance of birds on the European Sites are discussed

Fossils: Digging Into the Past

Fossils collected in Renaissance collection cabinets were items of wonder and curiosity. Although sometimes mistaken for other pieces of naturalia, they were widely collected by owners of princely cabinets and scholarly collections.Though naturalists and collectors often kept fossils in their collections, they did not have the same understanding as we do today of what they are. Due to their belief in mythological monsters and naturalia with magical properties, there were often misinterpretations or mislabeled objects to something they were not. According to Kenseth’s “A World of Wonders in One Closet Shut,” some collectors believed that fossilized shark’s teeth were “adders’ tongues,” and that they could be used as antidotes to poison. Just as whale ribs were mistaken for “giant bones,” and narwhal tusks were mistaken for “unicorn horns,” fossils were also often misunderstood. [excerpt

Participation, Preferences, and Characteristics of Outlying-Cabin Users in Alaska National Forests

The development and management of public-use cabins have been planned, or at least considered, by several federal and state agencies in Alaska. This bulletin reports the results of a pilot study of the cabin program of the U.S. Forest Service. There are problems of aggregated data which did not allow for detailed analysis; however, the report does provide an overview of the Forest Service outlying cabin program-who uses it, how they use it, and how they feel about it. The manager should be careful in applying the results without consideration of the total recreational spectrum, i.e., where the cabin program fits within this spectrum, and its cost in terms of other recreation opportunities that may be specified. It is the opinion of the authors that it would be unwise to simply mass reproduce the outlying cabin program in all areas having periods of inclement weather. The study sampled only cabin users-not all users or potential users of the particular landscape setting. To over-emphasize an expanded cabin program would reduce the continuum of opportunities. While subsequent studies of the cabin user population would likely find this group to prefer the new program, the users who did not prefer it or who were unwilling to adopt to new conditions would have been displaced. Thus, while the results have some direct applicability, it is also important to consider the maintenance of the continuum of recreational opportunities, only one portion of which is covered by outlying cabins

The Solent Disturbance & Mitigation Project. Phase II – results of the Solent household survey

This report sets out the results of the postal household survey component of the Solent Disturbance and Mitigation project. The work was commissioned by the Solent Forum in response to concerns over the impact of recreational pressure on features of the Solent SPA, SAC and Ramsar Sites. Of particular concern are the cumulative impacts of recreational use arising from potential new housing developments in Chichester District and South Hampshire. The household survey was distributed to 5000 households within 25km of the coastline between Hurst Castle, including the north shoreline of the Isle of Wight. The questionnaires and reminders were sent between October and December 2010. The household survey contained three sections which elicited information relating to general and specific visits to the coast and household demographics. A total of 1382 completed questionnaires were returned and 42% of these households had visited the coast the week prior to completing the survey. Only 4% of households (56) stated they never visited the coast. Households which did not visit the coast contained a lower number of people, lower number of dogs and a higher percentage did not have regular access to a private vehicle when compared to households that made regular coastal visits. Of the households which visited the coast, 50% visited at least once a week. A total of 55% of households visited the coast equally all year and an additional 39% of households made more visits in the summer. There was a significant difference in coastal visit frequency between households which owned a least one dog and non dog owning households, with dog owning households making more visits. There was no significant difference in visit frequency between households who had garden access or whether the household dwelling type was a flat or ‘non- flat’. The 1155 households providing full responses to the survey made an estimated annual total of 153,433 visits to the Solent coastline. The project and this survey divided the coastline into 103 numbered sections. Households made on average 133 annual coastal visits to 3.7 different sections of the coastline. On average each section received a total of 1490 annual visits but the number of coastal visits made to different sections was significantly different. The most frequently given activities undertaken during a coastal visit were walking (20% of all activity responses) and enjoying the scenery (20%), followed by being on the beach (11%) and meeting up with friends (11% of all activity responses). Households indicated where they undertook their activity during the coastal visit and for 47% of the visit responses the activity (walking, cycling, enjoying the scenery etc) was undertaken on the sea wall or the river bank. A further 39% of responses by households indicated they venture onto the beach/mudflat and 15% of responses actually took to the water. The majority (52%) of coastal visits by households were made by car with 39% made by foot, 4% by bicycle and 5% by public transport. Of the households which made visits by car, 50% travelled 9.5km or less by road to the section they visited and 90% travelled 29.0km or less to their visited section by road. Of the households who visited specific sections by foot half lived within 1.0km of the section (straight line distance from postcode to nearest point on section) and 90% lived within 4.0km of the visited section. Features that act as a deterrent for some households when selecting a coastal location to visit may also attract other households. For example, a requirement for dogs to be on leads and the presence of dog restrictions is rated as attractive to non dog owning households but as a deterrent by dog owning households. By far the most popular attractive feature when households choose which coastal location to visit was ‘sea views and attractive scenery’ followed by ‘feel safe’, ‘ability to do a range of different walks/routes ‘and the ‘presence of wildlife’. Predictions were derived by fitting formal statistical models to the observed (household survey) data. Specifically these models used observed visitor numbers per section per distance band and analysed these in relation to factors representing distance to section and section characteristics. Different models are presented within the report and separate models were generated for car and foot visitors, with each model showing a declining visitor rate with distance from the section – i.e. the further away people live the fewer visits they make. These models suggest some 52 million visits are made each year, by households within a 30km radius of the coastline between Hurst Castle to Chichester Harbour, including the north shore of the Isle of Wight. The models identify Portsmouth’s seafront (South Parade Pier to Fort Cumberland) as the most heavily visited coastal section, with over 3 million household visits per annum. These predictive visit models will be used alongside the bird models, commissioned separately and subject to a further report, to assess the impacts of disturbance to wintering birds under different housing scenarios. The use of the visitor models and how they will link to the bird models within the next stages of the Solent Disturbance and Mitigation Project are discussed