Post provided by Christophe Laplanche, Tiago Marques and Len Thomas
1km Deep
Most marine mammal species spend the majority of their lifetime at sea… underwater. Some species (like sperm whales, beaked whales, and elephant seals) can go routinely as deep as 1000m below sea level. To mammals like us, these incredible depths seem uninhabitable. It’s cold, dark, under high pressure (100kg/cm²) and 1km fromair! Yet deep-diving marine mammals thrive there and have colonized every deep ocean on the planet. They have developed amazing capabilities for that purpose – including efficient swimming, an advanced auditory system, sonar (in some cases), thermal insulation, extreme breath holding abilities and resistance to high pressure.
How is that possible?
Spending most of their time at depth makes them quite difficult to study. And we have a lot of questions to ask them. How do they balance swimming cost versus food intake? Do they forage cooperatively, in groups? For those with sonar, how does it work? With increasing human activities (oil exploration, military sonar, sea transport, fishing etc.) an important new question arises: how do they cope with us?
Finding a call of a particular primate species within hours and hours of audio recordings of a forest is no easy task; like finding a ‘needle in a haystack’ so to speak. Automated acoustic monitoring relies on the ability of researchers to easily locate and isolate acoustic signals produced by species of interest from all other sources of noise in the forest, i.e. the background noise. This can be much harder than it sounds. Think about whenever you have to use any kind of voice recognition system: seeking out a quiet room will greatly improve the chances you are understood by the robot-like voice on the other end of the phone. If you ever set foot in a rainforest the first thing you’ll notice is that it is anything but quiet. In fact characterizing and quantifying soundscapes has become a marker for the complexity of the biodiversity present in a given environment.
Primate monitoring programmes can learn a great deal from cetacean research where Passive Acoustic Monitoring (PAM) is the norm (since individuals are rarely observable visually). Research on bats and birds can provide excellent examples to follow as well. Automated algorithm approaches including machine learning techniques, spectral cross-correlation, Gaussian mixture models, and random forests have been used in these fields to be able to detect and classify audio recordings using a trained automated system. Such automated approaches are often investigated for a single species but impressive across-taxa efforts have also been initiated within a framework of real-time acoustic monitoring. Implementing these in other research fields could lead to significant advances. Continue reading “Progress and Future Directions for Passive Acoustic Monitoring: Listening Out for New Conservation Opportunities”
Applied ecology can be defined as scientific knowledge that helps in making good management decisions. Scientists have a natural desire to collect information, managers want that information so that they know they are doing the right thing, and both generally act under the assumption that more information equals better decisions. This is generally correct, since information helps us make, well, informed decisions. Therefore, when our ecological knowledge is uncertain (which is practically always the case) we usually advocate further research.
On the other hand, however, information comes at a cost. It may cost money to collect it and take time to set up studies: both are usually in short supply. We can’t learn everything and often the information we can actually collect is still imperfect. So how do we determine if that additional piece of information we’d like to have is really valuable for our management?
In decision analysis, the value of information is the improvement in the outcomes of our actions that we would expect if we could reduce or eliminate uncertainty before making a decision. Previously applied in engineering, economics and healthcare planning, VOI is also intuitively appealing for environmental management, where decisions must be made in the face of ubiquitous uncertainty. Knowing the value of information can assist in designing monitoring and experimental programs, implementing adaptive management and prioritising sources of uncertainty. In other words, it can help applied ecologists and conservation managers find a focused, transparent way to address the inevitable need for “more data”.
An increasing number of studies are applying VOI to conservation management; however, in spite of its potential the technique is still underused in real-world applications, particularly beyond the small community of applied ecologists trained in decision-analytic methods.
Click Image to begin a Prezi Presentation on Value of Information
In summary, three things determine the value of information:
How much we already know (the more we know, the less beneficial it is to collect more information)
Whether and how we would react to that extra information by changing actions, and how much better would the updated action be
How good is the information we can actually get (think about sample sizes, imperfect detection, time lags, etc)
Lidar point cloud from a scanned Eucalyptus tree (left) with colours correlating to point density (blue to red moving from high to low density). On the right is the reconstructed tree volume from which mass can be estimated.
A terrestrial laser scanning technique that allows the structure of vegetation to be 3D-mapped to the millimetre is more accurate in determining the biomass of trees and carbon stocks in forests than current methods, according to new research involving UCL.
The research paper, an international collaboration led by Wageningen University, is published today in Methods in Ecology and Evolution and demonstrates the technique in Australian forests.
The study authors believe it could be an important development in the monitoring of carbon stocks for worldwide climate policy-making. Both above-ground biomass and carbon stocks are important details for UN-REDD, the United Nations initiative on Reducing Emissions from Deforestation and forest Degradation that is striving to keep the destruction of forests in check and thereby preserve the uptake of carbon by trees.
Paper co-author Dr Mat Disney (UCL Geography) said: “This new paper shows how effectively we can now turn highly-accurate laser measurements, comprising millions of 3D laser points, into estimates of tree mass. Weighing trees is really hard – time Continue reading “Laser scanning accurately ‘weighs’ trees”
A new Methods paper comparing SCUBA diving to bubble-free diving suggests that fish are deterred by the sound of SCUBA bubbles, particularly in heavily fished areas, which can result in potentially biased fish counts and research conclusions. Steven Lindfield and colleagues from the University of Western Australia studied coral reef fish populations in Guam using two diving systems: the commonly used SCUBA equipment that produces … Continue reading Noisy SCUBA bubbles scare fish(shh!)
Motion sensing technology, best known in computer games, is vastly improving Queensland scientists’ ability to quantify habitat complexity in mangroves.
The Kinect line of devices developed by Microsoft for Xbox consoles and Windows PCs is marrying gaming technology with ecological research to deliver precise three-dimensional data in greater efficiency and at a fraction of the cost of current imaging techniques.
By Pat Backwell Associate Editor, Methods in Ecology and Evolution Is it necessary to study animals in their natural environment? It is often hot, uncomfortable, tiring, and rainy. You come home with mosquito bites, sore feet and sunburn. Can’t you just collect the animals and study them in the laboratory? Those of us who spend long periods in the field, watching real animals doing real … Continue reading Is fieldwork essential?
In the 4th and final installment of Barb Anderson’s INTECOL 2013 podcasts, she asks a number of delegates: What method has transformed your field the most, during your career?
The answers in this podcast are given by the following people:
Steve Hubbell, University of California, Los Angeles, USA (00.21)
Georgina Mace, University College London, UK (00.44)
Carsten Dormann, University of Freiburg, Germany (01.07)
At INTECOL 2013, Methods’ Associate Editor, Barb Anderson, interviewed a number of delegates and asked them: What is the newest method that you currently use?
The answers in this podcast are given by the following people:
Bill Sutherland, University of Cambridge, UK (00.18)
Georgina Mace, University College London, UK (01.04)
The Tea Bag Index is an innovative, cost-effective, well-standardised method recently covered in MEE, used to gather data on decomposition rate and litter stabilisation using commercially available tea bags as standardised test kits. In this video, David Warton interviews 2 of the authors, Joost Keuskamp and Mariet Hefting from Utrecht University, who explain how it works and what they plan to do with it in … Continue reading An interview with the Tea Bag Index team
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