A study of the benthic community, with particular reference to the chironomidae, of shallow, brackish lagoons created for the management of a bird reserve

In 2 volsAvailable from British Library Document Supply Centre- DSC:DX97602 / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo

Developing an indicator of the abundance, extent and impact of invasive non-native species. Final report

This report describes an indicator of the abundance, extent and impact of invasive non-native species in Great Britain. The main ideas and options for the abundance indicator and for the impact indicator are considered. A third type of indicator, the annual rate of establishment of new non-native species, is outlined, with provisional data presented only for England. Most of the options for the abundance indicator do not in fact measure abundance, but use either frequency in samples or frequency in recording scheme data as a substitute. An exception is the Breeding Bird Survey, for which numbers of individuals are counted. Several well-recorded groups of organisms have no non-native species (e.g. butterflies and lichens) or exceedingly few non-native species (macro-moths). Datasets selected for the abundance indicator were the Breeding Bird Survey (birds and mammals), Countryside Survey (vascular plants), British Bryological Society data (bryophytes) and Marine Biological Society data (marine organisms). From samples of records in each species group, the non-native component was calculated as proportion of all species sampled. This provided a temporal trend in non-native proportions, which were calculated separately for England, Scotland and Wales. The GB trend was derived by combining the trends for each component country, weighted by the area of each. Finally, the overall trend was calculated as a weighted geometric mean of trends for each species group, converted to an index by dividing by a constant to start at 1 in the baseline year 1990. The weights applied were birds 20%, mammals 20%, vascular plants 30%, bryophytes 10% and marine organisms 20%. There were no suitable datasets from the freshwater environment. No direct measure of impact could feasibly be calculated for all invasive species in Great Britain. As a substitute, an indicator based on the extent of occupation by invasive species was adopted. The methodology for the indicator was based on a scheme developed by the Belgian Forum on Invasive Species. First, a list of the most invasive species was compiled, using a simplified environmental impact assessment protocol to assign species to threat categories. Then the extent of each invasive species was scored for 1960, 1970, 1980, 1990, 2000 and 2007, on a 5-point scale ranging from 0 (absent) to 4 (present in more than half the territory). Extent scores were added to obtain the indicator. Over the period 1990-2007, the mean indexed proportion of records of non-native species in samples of birds, mammals, plants and marine life rose by 23%. Except for mammals, the absolute proportion was still only about 1% of the total. The assessment protocol assigned 49 species in Great Britain to the highest threat category. There were 3 marine plants, 16 marine animals, 4 freshwater plants, 8 freshwater animals, 8 terrestrial plants and 10 terrestrial animals. Over the period 1990-2007, the summed extent scores of these invasive non-native species rose by 40%. The increase of invasive species was particularly large in the freshwater and marine environments. Although non-native species are a potential threat, they are still only a small proportion of the animals and plants to be found in most of the land area and coasts of Great Britain. Vertebrates stand out as the most invasive group. For all groups of organisms reported here, England was the country most affected by non-native species. Scotland was the least affected. Wales was intermediate. In 2008, values of the impact indicator for the three countries were respectively 135, 73 and 95. Most species groups showed a trend over time towards an increasingly non-native biota. If the indicator is to be developed further, the main priority is to include freshwater species in the abundance component. Because the list of invasive species depends on expert judgement, it needs to be reviewed and if necessary updated at regular intervals. Further analytical work is desirable, to improve the signal obtained from recording scheme data

Assessing the effects of scaring starlings roosting on Blackpool piers

Includes bibliographical referencesAvailable from British Library Document Supply Centre- DSC:2354. 730(no 302) / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo

Travelling through a warming world: Climate change and migratory species

Long-distance migrations are among the wonders of the natural world, but this multi-taxon review shows that the characteristics of species that undertake such movements appear to make them particularly vulnerable to detrimental impacts of climate change. Migrants are key components of biological systems in high latitude regions, where the speed and magnitude of climate change impacts are greatest. They also rely on highly productive seasonal habitats, including wetlands and ocean upwellings that, with climate change, may become less food-rich and predictable in space and time. While migrants are adapted to adjust their behaviour with annual changes in the weather, the decoupling of climatic variables between geographically separate breeding and non-breeding grounds is beginning to result in mistimed migration. Furthermore, human land-use and activity patterns will constrain the ability of many species to modify their migratory routes and may increase the stress induced by climate change. Adapting conservation strategies for migrants in the light of climate change will require substantial shifts in site designation policies, flexibility of management strategies and the integration of forward planning for both people and wildlife. While adaptation to changes may be feasible for some terrestrial systems, wildlife in the marine ecosystem may be more dependent on the degree of climate change mitigation that is achievable