(Article copied from Mongabay.com)
Researchers have discovered a new species of river dolphin from the Amazon.
Writing in the journal Plos One, scientists led by Tomas Hrbek of Brazil's Federal University of Amazonas formally describe Inia araguaiaensis, a freshwater dolphin that inhabits the Araguaia River Basin. It is the first true river dolphin discovered since 1918.
The discovery came after Hrbek and colleagues noticed that a group of river dolphins in the Araguaia was isolated from other Amazon dolphins by a series of rapids. Conducting genetic analysis, the researchers found the Araguaian boto (Inia araguaiaensis) to be distinct enough from other Amazon dolphins to be classified as a different species. The scientists estimate that the dolphin species diverged some two million years ago, corresponding to the separation of the Araguaia-Tocantins basin from the Amazon basin.
The differences between the Araguaian boto and their closest relatives, Inia geoffrensis and Inia boliviensis, extend beyond genetics. The Araguaian boto is smaller, has a different number of teeth, and has a wider skull.
The new discovery has immediate implications for conservation. While river dolphins are generally not hunted directly in most of the Amazon due to local taboos, they do face risks from hydroelectric projects, pollution from urban areas and agriculture, boat traffic, and accidental bycatch. Moreover the Araguaian boto population is apparently quite low, according to the new research, which estimates the number of individuals at around 1,000.
"Populations of the middle and upper Tocantins River are fragmented by six hydroelectric dams, not including the Tucurui dam, and are likely to have very few individuals," the authors write. "Since the 1960’s the Araguaia River basin has been experiencing significant anthropogenic pressure via agricultural and ranching activities, and the construction of hydroelectric dams, all of which have had negative effects on many biotic and abiotic aspects of the functioning of the Araguaia River ecosystem which I. araguaiaensis inhabits. Similarly I. araguaiaensis in the Tocantins River is affected by agricultural and industrial development, and is fragmented into isolated populations by hydroelectric dams. Interpreting these data using IUCN criteria, Inia araguaiaensis should minimally be considered vulnerable (VU Red List category)."
A vulnerable listing may force policymakers in Brazil to consider the species' plight when planning new industrial developments in the basin. Brazil is currently in the midst of a dam-building spree throughout the Amazon Basin, which environmentalists warn could disrupt the ecological functioning of the world's largest river system.
CITATION: Hrbek T, da Silva VMF, Dutra N, Gravena W, Martin AR, et al. (2014) A New Species of River Dolphin from Brazil or: How Little Do We Know Our Biodiversity. PLoS ONE 9(1): e83623. doi:10.1371/journal.pone.0083623
Read more at http://news.mongabay.com/2014/0123-new-amazon-dolphin.html#XBZsJPqp2Ao0dHPd.99
I tend to be an Anthropocene optimist - believing we can find ways out of the current pathways of destruction of the biosphere and being able to balance the needs for development and conservation. But it is hard not to feel depressed when seeing magnificent forest (even logged forest) being bulldozered into oil palm plantations, to meet the world's demand for oil fats in foods, soaps, cosmetics and biofuel. In the last 20 years such plantations have sprawled across Indonesia and Malaysia, and now they are just beginning to make headway into Africa and Amazonia. Do rainforests really need to be destroyed so utterly for this? Pictues are from new plantation clearance in southern Sabah, Malaysian Borneo.
This month we had the first field visit of our new NERC-funded consortium project, BALI (Biodiversity and Land Use Interactions), together with its sister project (aptly names LOMBOK). This visit brought together a range of the principal investigators of the project. We first met up with local collaborators at the University of Malaysia in Sabah (UMS) in Kota Kinabalu, and the Forestry Research Centre (FRC) in Sepilok. Then we took flights out to Tawau and headed out to the field camp of the SAFE project, which will form the core of the proposed work.
Our aim is to explore our biodiversity, biogeochemical cycling and ecosystem function interact along a gradient of disturbance ranging from old-growth rainforest (at Maliau Basin and Lambir Hills), through forests that have been logged at various intensities (the SAFE project) through to oil palm plantations. We will explore the role of biodiversity in four groups: trees, termites, ants and myccorhizal fungi (plus soil microbes in general), and the work will be centred on the GEM intensive monitoring plots that my team have installed and been operating for several years.
The project is new, different from anything I have done before, and it will be exciting to learn so much more from colleagues in such a broad consortium.
A nice little education animation explaining the role that rainforests have in making rain
I am visiting Sabah for a week with colleagues for the start-up of our large NERC-funded consortium project, BALI. More on the science later, but here are some wonderful moments in Sepilok Forest, at the Rainforest Discovery Trail, and (the last few shots) from the adjoining Orangutan Rehabilitation Centre.
The impact of large animal extinctions on nutrient fluxes in early river valley civilizations
The extinction of megafauna worldwide preceded the establishment of many early agricultural civilizations, including those in Sumeria, the Indus Valley, the Nile and China. Was there any link between the megafaunal extinction and the nutrient dynamics of these early civilizations? In this new paper in Ecosphere, led by Chris Doughty, we use the mathematical framework we recently developed (see our papers in Nature Geoscience and PLOS One in 2013) to explore and speculate on how the loss of nutrient transfer through dung may have impacted these early civilizations. Without any direct data, this remains speculation, but may stimulate thinking on the interactions between Pleistocene megafaunal extinction and the rise of agricultural humanity.
Doughty C.E, Wolf A., and Y Malhi Y. 2013. The impact of large animal extinctions on nutrient fluxes in early river valley civilizations. Ecosphere 4:art148. http://dx.doi.org/10.1890/ES13-00221.1
Herbivory makes major contributions to ecosystem carbon and nutrient cycling in tropical forests
We have a new paper in Ecology Letters, led by Dan Metcalfe, examining the variation in leaf herbivory along our 3000 m elevation transect in the Peruvian Amazon-Andes. This involved scanning a subset of the leaves that our field teams have been regularly collecting along the transect, and painstakingly working out what fraction of the leaves had been consumed. We found that herbivory was strongly influenced by temperature (higher temperature = more herbivory) and secondarily by leaf phosphorus content. As we have a full description of the carbon cycle of these forests, we were able to calculate what contribution herbivory makes to the whole carbon cycle of the forest, the first time this has been done for tropical forests.
The paper can be downloaded here.
Metcalfe, D. B., Asner, G. P., Martin, R. E., Silva Espejo, J. E., Huasco, W. H., Farfán Amézquita, F. F., Carranza-Jimenez, L., Galiano Cabrera, D. F., Baca, L. D., Sinca, F., Huaraca Quispe, L. P., Taype, I. A., Mora, L. E., Dávila, A. R., Solórzano, M. M., Puma Vilca, B. L., Laupa Román, J. M., Guerra Bustios, P. C., Revilla, N. S., Tupayachi, R., Girardin, C. A. J., Doughty, C. E., Malhi, Y. (2013), Herbivory makes major contributions to ecosystem carbon and nutrient cycling in tropical forests. Ecology Letters. doi: 10.1111/ele.12233. Supporting Information.
Rainforest News for 2013
Happy New Year!
Here is an excellent roundup of tropical rainforest news for 2013, from Mongabay.
Yadvinder Malhi is an ecosytem ecologist and Professor of Ecosystem Science at Oxford University