Despite the frequent public preconception that urban waterways such as canals and ditches are polluted eyesores, devoid of almost all wildlife, recent research has shown that they can have more macroinvertebrate diversity than similar water systems in rural areas. They can also provide habitat for several endangered species.

Urban habitats may provide an important refuge for biodiversity in the face of climate change and increasing fragmentation. However, to date there has been little data provided to assess the conservation value of urban areas, and very few studies focusing on urban water systems.

A new Dutch study compared the biodiversity value of urban waterways in two towns in the Netherlands with natural and manmade drainage systems in rural areas, such as small streams and rivulets. Macroinvertebrate species, including snails, mites, flies and exotic crustaceans, were studied.

Urban waterways with low levels of nutrients (particularly nitrogen and phosphorous), were found to have the highest diversity of macroinvertebrates, and the highest number of endangered species. Waters with high levels of nutrients and poorly developed vegetation meanwhile had low macroinvertebrate diversity. The number of exotic crustaceans was high in nutrient-rich waters, probably because they are better able to cope with harsher conditions, such as low oxygen levels, than native species.

The researchers concluded that the key factors for macroinvertebrate biodiversity in urban water systems are levels of nitrates, sediment composition, transparency and submerged vegetation.

For further information, please see: Vermonden, K., Leuven, R.S.E.W., van der Velde, G. et al. (2009). Urban drainage systems: An undervalued habitat for aquatic macroinvertebrates. Biological Conservation. 142: 1105-1115.

The outlook for endangered albatross species has dramatically improved, thanks to the success of an international conservation programme implemented by the RSPB and Birdlife International.

The Albatross Task Force (ATF) was established in 2006 in order to reduce the number of accidental albatross deaths caused by long-line fishing. At the time, it was estimated that one bird was killed every five minutes from long line fishing, and 19 of the 22 albatross species were under threat from extinction.

The birds were dying because they were taking bait from fishing lines fed into the sea from boats fishing for tuna or swordfish. Once they swallowed the bait, they would become caught on the hook, dragged underwater and drown.

Specialist instructors from the ATF went out with fishermen and taught them techniques that would stop the birds becoming entangled. They were encouraged to fish at night, weight their lines and attach streamers to the back of vessels to scare the birds away. Government legislation also played its part by stipulating that no more than 25 birds could be caught as “by-catch” during trips.

The programme has been heralded as a resounding success, and has reduced deaths by up to 85% in some locations.

Dr Ross Wanless, coordinator of the Birdlife programme in Africa, said: “Changing entrenched attitudes and practices is a slow process, but the ATF has shown that by working with government and industry, change is possible.”

Whilst the 19 species are not freed from the threat of extinction yet- many are still snagged by trawlers, breeding is slow and habitats are endangered – the campaign is likely to have made a remarkable impact on their population stability and its success cannot be understated.

Learn more about the ‘Save the Albatross’ Campaign here.

Read more about this story at the BBC News website and the Times News website.

The global decline in frog populations has been attributed to an increase in infectious diseases. However findings in Nature reveal a link between parasitic infection and local interaction between phosphate fertilisers and herbicides.

The study focused on leopard frogs from wetlands in Minnesota, USA, and these frogs were examined for trematode larvae – a type of parasitic flatworm. Trematodes are known to cause kidney damage and occasionally deformities in amphibians. The researchers also looked for indicative signs of water pollution, by measuring the level of melanomacrophage liver cells, which are involved in amphibian immune response.

Of the many possible factors contributing to these ailments in the frogs, the strongest predictor of larval infection was the herbicide atrazine combined with high phosphate levels. High levels of the atrazine herbicide were correlated with low levels of melanomacrophage cells, indicating the herbicide suppressed the frogs’ immune response, increasing susceptibility to the trematodes.

A probable cause of the interaction was revealed, when the frogs were placed in tanks exposed to supposed environmental levels of these chemical in the U.S. Atrazine reduced phytoplankton growth, creating clearer water and higher levels of nutrients. This stimulated algal growth, which in turn encouraged gastropods. Gastropods play host to trematodes, acting as a vector to the amphibians. Since wetland birds are the primary host of trematode eggs, as the authors suggest, these must be present along with the elevated phosphate levels and herbicide for the interactive effect to take place.

The findings highlight problems in the European and American systems for registering chemicals. Although the chemicals have no direct effect on mortality independently, the combined effect results in this pollution-disease pathway and would not be identified under existing pollutant control tests.

Many European countries banned its use even before EU legislation withdrew support for its use in 2004, because of concerns over concentrations in groundwater. Atrazine is used widely across the world for corn and sorghum production. There is still some limited support for its use in European countries, although the UK, Ireland, Spain and Portugal no longer have any support for it.

Amphibians are becoming increasingly threatened across the globe, with many species expected to become extinct by 2050. Amphibian fungal infections, particularly Chytridiomycosis are on the rise across the globe, possibly exacerbated by climate change. Chytridiomycosis is thought to have originated in South Africa, although nobody is entirely certain where it began.

Adapted from the Science Environment Policy bulletin, Source: Rohr, J.R., Schotthoefer, A.M., Raffel, T.R., et al. (2008). Agrochemicals increase trematode infections in a declining amphibian species. Nature. 455: 1235-1240.

Scientists have recently developed a new computer modeling system that will improve the way in which river basins are assessed for the European Water Framework Directive.

The system has been named the Elbe decision support system, (Elbe-DSS), after the river it was initially developed for assessing, the River Elbe, one of the largest in Europe.

The system will specifically monitor the following elements of river catchment:

One of the strengths of this system is that it will help cross-border collaboration in tackling river management objectives. The system can be intelligently manipulated in order to assess the likely impacts of likely changes in variables affecting the catchment area, such as reforestation and increased/decreased fertiliser input.

Having tested theory against practice, it has proved to be reliable in predicting nutrient levels across the whole river basin. Because the system can be applied at various spatial scales, it means that approaches can be taken at specific locations across the modeled area in an efficient way. It also allows management actions to be ranked in importance according to modeled assumptions about future environmental and demographic changes.

The system is free and available from the German Federal Institute of Hydrology, (although the website is currently under construction and written in German).

This article is adapted from the Science Environment Policy Bulletin, Source: Lautenbach, S., Berlekamp, J., Graf, N. et al. (2009). Scenario analysis and management options for sustainable river basin management: Application of the Elbe DSS. Environmental Modelling and Software. 24(1): 26-43.

The Carbon Trust, a government funded agency, is to unveil plans that will set the agenda for algal biofuels becoming a significant alternative to fossil fuels by 2020. £26m has been allocated to research and development of infrastructure that will make algal biofuels a commercial reality, facilitating their use for UK road transport.

Given that transport contributes 25 per cent of Britain’s greenhouse gas emissions, finding a ‘carbon neutral’ alternative to fossil fuels is essential. Algae do not replicate the problems associated with crop-type biofuels, which have contributed to a massive rise in food prices as well as widespread natural habitat loss.

John Loughhead, executive director of the UK Energy Research Council, said:

“Algae are potentially attractive means to harvest solar energy: they reproduce themselves, so there’s no manufacturing cost for the solar converter, they can live in areas not useful for food or similar productive use, they don’t need clean or even fresh water so don’t add to global water stress, and can give oils, biomass, or even hydrogen as a product. Perhaps they’ll be the stem cells of the energy world.”

The Carbon Trust believes that by 2030, 12% of aviation fuel and 6% of road transport fuel could be replaced by algal biofuels, resulting in a net reduction in 160million tonnes of carbon.

Recent hikes in oil prices mean that interest could has been renewed in algal biofuels. Initial efforts in the 80s appeared promising, but commercial viability was always one step away because these fuels simply couldn’t compete with the cheap oil of that era.

Transport Minister Andrew Adonis supports the move towards sustainable biofuels: “This project demonstrates our commitment to ensuring that second generation biofuels are truly sustainable — and will further our understanding of the potential for microalgae to be refined for use in renewable transport fuel development, to help reduce carbon dioxide emissions.”

The Wellcome Trust is backing a company developing some of the most advanced genetically modified algal biofuels, Sapphire Energy.

Previous hysterical reports in the media have made blanket references to biofuels, overlooking the disparity between the unsustainable fuels such as palm oil grown in south east Asia, with promising options such as algae. It is encouraging therefore that the mass media and ministers are now making a clear distinction between these, and looking closer at viable alternatives to fossil fuels.

Two non-native invasive species; the chinese mitten crab and the non-native crayfishs‘ ranges are set to overlap in the near future.

Both crustaceans are formidable predators, with a tendency to damage the ecology of their local environment. The signal crayfish Pacifastacus leniusculus, has so far caused the most widespread damage, in part because it is a vector for the plague disease that affects our native white-clawed crayfish Austropotamobius pallipes.

Speaking to the BBC, ecologist Stephanie Peay said: “Where the non-natives move in, the white-clawed crayfish [sic] are lost. Survey work has shown that it only takes between four and seven years from first arrival to achieve a complete local extinction. The only future for the white claws is in isolated water bodies that are completely free from non-native crayfish.”

Both the mitten crab and the crayfish have a broad, generalist diet, the mitten crab being particularly unfussy when it comes to prey items, (plants, fish eggs and molluscs among these). The ecological niches of both species directly overlap, so it is likely there will be some kind of clash when the two species inevitably meet.

When either species is present in any British waterway, they will cause an overall loss in biological diversity and abundance of native species. One of the known mechanisms leading to invasiveness is enemy release. Because of the practicality of introducing natural enemies to curb these exotic beasts, this approach will remain unlikely. Conventional removal of these species by local authorities is currently probably the best method of dealing with these alien predators.

Defra’s invasive non-native species framework strategy can be downloaded here.

The Environment Agency website lists some of the UK’s worst offending non-native invasives.