Biomechanically-Aware Behaviour Recognition using Accelerometers

Post provided by Pritish Chakravarty

 

Accelerometers, Ground Truthing, and Supervised Learning

Accelerometers are sensitive to movement and the lack of it. They are not sentient and must recognise animal behaviour based on a human observer’s cognition. Therefore, remote recognition of behaviour using accelerometers requires ground truth data which is based on human observation or knowledge. The need for validated behavioural information and for automating the analysis of the vast amounts of data collected today, have resulted in many studies opting for supervised machine learning approaches.

Ground-truthing. The acceleration data stream (recorded using the animal-borne data logger, bottom-left) is synchronised with simultaneously recorded video (near top right). Picture credit: Kamiar Aminian

In such approaches, the process of ground truthing involves time-synchronising acceleration signals with simultaneously recorded video, having an animal behaviour expert create an ethogram, and then annotate the video according to this ethogram. This links the recorded acceleration signal to the stream of observed animal behaviours that produced it. After this, acceleration signals are chopped up into finite sections of pre-set size (e.g. two seconds), called windows. From acceleration data within windows, quantities called ‘features’ are engineered with the aim of summarising characteristics of the acceleration signal. Typically, ~15-20 features are computed. Good features will have similar values for the same behaviour, and different values for different behaviours.

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Issue 11.4: Population Dynamics, Machine Learning, Morphometrics and More

The April issue of Methods is now online!

The latest issue of Methods in Ecology and Evolution is now online! This month’s issue is a little shorter than our last few. But, as they say, good things come in small packages!

Senior Editor Lee Hsiang Liow has selected six Featured Articles this month. You can find out about all of them below. We’ve also got five Applications articles and a Practical Tools article in the April issue that we’re going to cover. Those six papers are freely available to everyone – no subscription required!

On top of all that, the April issue includes articles on camera traps, land cover classification, presence-absence sampling and more.

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Hyperoverlap: Detecting Overlap in n-Dimensional Space

Post provided by Matilda Brown, Barbara Holland, and Greg Jordan

Overlap can help us to learn why Microcachrys
is now only found in the mountains of
Tasmania. ©Greg Jordan

There are many reasons that we might be interested in whether individuals, species or populations overlap in multidimensional space.  In ecology and evolution, we might be interested in climatic overlap, morphological overlap, phenological or biochemical overlap. We can use analyses of overlap to study resource partitioning, evolutionary histories and palaeoenvironmental conditions, or to inform conservation management and taxonomy. Even these represent only a subset of the possible cases in which we might want to investigate overlap between entities. Databases such as GBIF, TRY and WorldClim make vast amounts of data publicly available for these investigations. However, these studies require complex multivariate data and distilling such data into meaningful conclusions is no walk in the park.

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Teaching Computers to Think like Ecologists

Post provided by CHRIS TERRY

Artificial intelligence (or AI) is an enormously hot topic, regularly hitting the news with the latest milestone where computers matching or exceeding the capacity of humans at a particular task. For ecologists, one of the most exciting and promising uses of artificial intelligence is the automatic identification of species. If this could be reliably cracked, the streams of real-time species distribution data that could be unlocked worldwide would be phenomenal.

ladybird-stock_thumbDespite the hype and rapid improvements, we’re not quite there yet. Although AI naturalists have had some successes, they can also often make basic mistakes. But we shouldn’t be too harsh on the computers, since identifying the correct species just from a picture can be really hard. Ask an experienced naturalist and they’ll often need to know where and when the photo was taken. This information can be crucial for ruling out alternatives. There’s a reason why field guides include range maps!

Currently, most AI identification tools only use an image. So, we set out to see if a computer can be taught to think more like a human, and make use of this extra information. Continue reading

Issue 11.2: Stable Isotopes, in situ Monitoring, Image Analysis and more

The February issue of Methods is now online!

The latest issue of Methods in Ecology and Evolution is now online!

Executive Editor Rob Freckleton has selected six Featured Articles this month. You can find out about all of them below. We’ve also got six Applications articles and five Open Access articles in the February issue – we’ll talk about all of those here too.

On top of all that, the February issue includes articles on population genetics, ecological assemblages, and reconstruction of protein sequences.

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Using Artificial Intelligence to Track Birds’ Dark-of-Night Migrations

Below is a press release about the Methods in Ecology and Evolution article ‘MistNet: Measuring historical bird migration in the US using archived weather radar data and convolutional neural networks‘ taken from the University of Massachusetts Amherst.

Wood thrush. ©CheepShot

On many evenings during spring and fall migration, tens of millions of birds take flight at sunset and pass over our heads, unseen in the night sky. Though these flights have been recorded for decades by the National Weather Services’ network of constantly-scanning weather radars, until recently these data have been mostly out of reach for bird researchers.

“That’s because the sheer magnitude of information and lack of tools to analyse it made only limited studies possible,” says artificial intelligence (AI) researcher Dan Sheldon at the University of Massachusetts Amherst. Continue reading

Assessing Sea Turtle Populations: Can We Get a Hand From Drones and Deep Learning?

Post provided by PATRICK GRAY

An olive ridley sea turtle in Ostional, Costa Rica. ©Vanessa Bézy.

Understanding animal movement and population size is a challenge for researchers studying any megafauna species. Sea turtles though, add a whole additional level of complexity. These wide-ranging, swift, charismatic animals spend much of their time underwater and in remote places. When trying to track down and count turtles, this obstacle to understanding population size becomes a full-on barricade.

Censusing these animals doesn’t just satisfy our scientific curiosity. It’s critical for understanding the consequences of unsound fishing practices, the benefits of conservation policy, and overall trends in population health for sea turtles, of which, six out of seven species range from vulnerable to critically endangered. Continue reading

Issue 10.4: Bayesian Models, Isoscapes, Camera Traps and More

The April issue of Methods is now online!

This month we’re thinking about hierarchical Bayesian models and Approximate Bayesian Computation, improving ecological niche models, and learning how to make our own Environmental Microcontroller Units (more on that below). We’ve got articles on Phylogenetics, Space (not outer space), Camera Traps and much more. Plus, there are six papers that are completely free to everybody, no subscription required!

Find out a little more about the new issue of Methods in Ecology and Evolution (including details about the bobcat on this month’s cover) below. Continue reading

New Technologies Could Help Conservationists Keep Better Track of Serengeti Wildebeest Herds

Below is a press release about the Methods in Ecology and Evolution article ‘A comparison of deep learning and citizen science techniques for counting wildlife in aerial survey images‘ taken from the University of Glasgow.

A wildebeest herd in the Serengeti. ©Daniel Rosengren

A wildebeest herd in the Serengeti. ©Daniel Rosengren

Mathematicians and conservationists from the UK, Africa and the United States have used machine-learning and citizen science techniques to accurately count wildebeest in the Serengeti National Park in Tanzania more rapidly than is possible using traditional methods.

Evaluating wildebeest abundance is currently extremely costly and time-intensive, requiring manual counts of animals in thousands of aerial photographs of their habitats. From those counts, which can take months to complete, wildlife researchers use statistical estimates to determine the size of the population. Detecting changes in the population helps wildlife managers make more informed decisions about how best to keep herds healthy and sustainable. Continue reading

Citizen Science Projects Have a Surprising New Partner – The Computer

Below is a press release about the Methods in Ecology and Evolution article ‘Identifying animal species in camera trap images using deep learning and citizen science‘ taken from the University of Minnesota-Twin Cities.

The computer’s accuracy rates for identifying specific species, like this warthog, are between 88.7 percent and 92.7 percent. Image credit: ©Panthera

The computer’s accuracy rates for identifying specific species, like this warthog, are between 88.7 percent and 92.7 percent. ©Panthera

For more than a decade, citizen science projects have helped researchers use the power of thousands of volunteers who help sort through datasets that are too large for a small research team. Previously, this data generally couldn’t be processed by computers because the work required skills that only humans could accomplish.

Now, computer machine learning techniques that teach the computer specific image recognition skills can be used in crowdsourcing projects to deal with massively increasing amounts of data—making computers a surprising new partner in citizen science projects.

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