Mangroves provide enormously important and economically valuable ecosystem services to coastal communities throughout the tropics. They provide at least US $1.6 billion each year in ecosystem services worldwide, but a startling statistic from a recent study is that eleven of the worlds 70 mangrove species (16%) are at elevated threat of extinction. The IUCN Mangrove Red List Assessment Team have recently published a peer reviewed assessment of the vulnerability to extinction risk to the worlds mangrove species. The teams assessment provides evidence that there are particular areas of geographical concern, such as the Atlantic and Pacific coasts of Central America, where as many as 40% of mangroves species present are threatened with extinction. In the Indo-Pacific region up to 14% of species are at risk. The article led by Beth Polidoro of the IUCN and published in the open access PLoS One finds that mangroves in the upper inter-tidal and estuarine environment are those species most at risk. This is principally because they are the first to be cleared from activities such as aquaculture and agriculture.

Not all areas show extinction risks, and noticeably only a small area of the Northern Territory in Australia shows any level of mangrove species extinction risk. These risks of extinction although important don’t however show the full problem, as the world is losing mangrove at an unprecedented rate. And this loss is not isolated to developing nations; mangroves are being routinely cleared for developments throughout Australia. This global loss should ring alarm bells. A well cited research article published in Nature in 2003 found that reefs in the Caribbean where mangrove had been removed contained 50% less fish biomass, and many studies have argued the value of mangrove in providing critical coastal protection.

A glimmer of hope comes from the passions of communities willing to get involved and support their own natural habitats. In the Burnett-Mary region of Queensland, communities are developing a ‘Mangrove-watch’ scheme to monitor their own mangroves and help protect the important ecosystem values of these habitats.

Note an extended version of this article was originally published on the Huffington Post here.  Also read about the study here on Futurity and here on the BBC.

Betting on biodiversity loss is a pretty sure thing.  The earth’s plant and animal species are disappearing at a sobering rate due to pressures including habitat loss, climate change, pollution and over-harvesting.  Despite a few success stories and steps in the right direction, we are falling far short of stemming these losses.

Biodiversity is the entire range of biological variety in the world, including the diversity of genotypes, species and ecosystems.  It can be measured on levels from DNA molecules all the way up to broad taxonomic categories such as families and phyla.  Monitoring the fate of any of these aspects of biodiversity at a global scale is a daunting task.  Thus, we know little about the rates and patterns of biodiversity loss or the effectiveness of global mitigation plans such as the 2002 Convention on Biological Diversity.

Dr. Stuart Butchart of the UNEP World Conservation Monitoring Centre and BirdLife International tackled the problem by assembling an international team of conservation scientists (that I was part of) to calculate trends in global biodiversity.  The idea was to assemble several dozen indices that we had sound, long term data for including population trends for birds and other vertebrates and the loss of habitats such as forests, seagrass beds and coral reefs.

As we recently reported in Science magazine (Butchart et al 2010), our analysis indicates that biodiversity has continued to decline over the past four decades with no detectable abatement for most indices.  This is largely due to increased pressures resulting from human population growth, economic development and globalization but it also seems clear that our international response to the biodiversity crisis has been inadequate.

Aggregated indices of (A) the state of biodiversity based on 9 indicators of species’ population trends, habitat extent/condition and community composition; (B) pressures on biodiversity based on 5 indicators of Ecological Footprint, nitrogen deposition, numbers of alien species, over-exploitation, and climatic impacts; and (C) responses for biodiversity based on 6 indicators of protected area extent and biodiversity coverage, policy responses to invasive alien species, sustainable forest management and biodiversity-related aid. Values in 1970 set to 1. Shading shows 95% confidence intervals derived from 1,000 bootstraps. Significant positive/upward (○) and negative/downward (●) inflections are indicated.

“Although nations have put in place some significant policies to slow biodiversity declines, these have been woefully inadequate, and the gap between the pressures on biodiversity and the responses is getting ever wider” – lead author Dr Stuart Butchart.

“Since 1970, we have reduced animal populations by 30%, the area of mangroves and sea grasses by 20% and the coverage of living corals by 40%”, said the United Nations Environment Programme’s Chief Scientist Prof Joseph Alcamo. “These losses are clearly unsustainable”

“While many responses have been in the right direction, the relevant policies have been inadequately targeted, implemented and funded. Above all, biodiversity concerns must be integrated across all parts of government and business, and the economic value of biodiversity needs to be accounted for adequately in decision making. Only then will we be able to address the problem,” says Ahmed Djoghlaf, Executive Secretary to the Convention on Biological Diversity.

Reference: Butchart, S. H. M., M. Walpole, B. Collen, A. van Strien, J. P. W. Scharlemann, R. E. A. Almond, J. E. M. Baillie, B. Bomhard, C. Brown, J. Bruno, K. E. Carpenter, G. M. Carr, J. Chanson, A. M. Chenery, J. Csirke, N. C. Davidson, F. Dentener, M. Foster, A. Galli, J. N. Galloway, P. Genovesi, R. D. Gregory, M. Hockings, V. Kapos, J.-F. Lamarque, F. Leverington, J. Loh, M. A. McGeoch, L. McRae, A. Minasyan, M. H. Morcillo, T. E. E. Oldfield, D. Pauly, S. Quader, C. Revenga, J. R. Sauer, B. Skolnik, D. Spear, D. Stanwell-Smith, S. N. Stuart, A. Symes, M. Tierney, T. D. Tyrrell, J.-C. Vie, and R. Watson. 2010. Global Biodiversity: Indicators of Recent Declines. Science: 1187512

Indicator trends for (A) the state of biodiversity, (B) pressures upon it, (C) responses to address its loss, and (D) the benefits humans derive from it. Data scaled to 1 in 1970 (or for first year of data if >1970), modeled (if >13 data points; see Table 1) and plotted on a logarithmic ordinate axis. Shading shows 95% confidence intervals except where unavailable.

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Oil spill threatens to eclipse the Exxon Valdez, reaches the shore on the Mississippi River delta,could become the worst environmental disaster in decades, leak might not be stopped for weeks.  Here’s what David Kennedy of the National Oceanic and Atmospheric Administration has to say:

“I am frightened. This is a very, very big thing. And the efforts that are going to be required to do anything about it, especially if it continues on, are just mind-boggling.”

210,000 gallons a day, and the conservative pundits don’t even bat an eye lid. Don’t worry, it’s ‘natural’.