What's that Sound? Scientists Tune in to National Park Audio Research
Elk, owls, coyotes, and snowmobiles all have been heard on Colorado State University campus lately. The sounds are coming from a listening laboratory where a research project between CSU and the National Park Service (NPS) is analyzing acoustic data recordings to inform and improve management of national parks across the country.
“Sounds, or the lack of them, play a significant role in visitor experiences and wildlife behavior in parks,” said Cecilia White, a research associate for the project. “Acoustic research is a growing field in natural resources sciences and has a variety of important applications from conservation to tourism.”
CSU is collaborating with the NPS Natural Sounds and Night Skies Division (NSNSD) to study detailed park audio recordings that provide valuable clues to wildlife and human park activity and their interaction. The audio data is collected through recording systems that are installed by NSNSD in selected parks for about a month at a time. The systems record audio (as mp3 files) and sound pressure levels (in decibels) and are designed to replicate the experience of a person on the ground.
NSNSD is part of the Natural Resource Stewardship & Science Directorate of the NPS and uses science, engineering, and technology to understand, restore, maintain, and protect acoustical environments and naturally dark skies throughout the National Park System. CSU researchers currently involved with the program are Ken Wilson, George Wittemyer, and Kevin Crooks with the Department of Fish, Wildlife, and Conservation Biology, and Lisa Angeloni with the Department of Biology.
Engaging Students in Acoustic ScienceIn 2013, the CSU project team created a program to give students the opportunity to gain acoustic research experience. The students are trained to distinguish different sounds and recognize how they appear on a spectrogram. Once they have tuned their senses, the students listen to recordings from the parks and identify the sounds they hear, such as animals, people, planes, or cars. They use software designed by NPS to compile the percentage of time a sound was heard, the volume of the sound, and the frequency of the sound.
The listening lab just hired seven new student researchers and has employed a total of 18 students since its inception.
The Sound of SuccessAcoustic research findings have already been incorporated into management policies. In Yellowstone National Park, the NSNSD documented where, how often, and how loud noise would occur under different management scenarios. Incorporating these data into its winter-use plan allowed Yellowstone to provide recreation benefits to oversnow vehicle users while protecting other visitors and wildlife from noise.
NSNSD acoustical data are also being used by Grand Canyon National Park to help manage air tours and protect visitors and park resources from the effects of aircraft noise.
The Division also projected noise level increases from a proposed highway expansion near Vicksburg National Military Park in Mississippi. In Glacier National Park, the NSNSD is studying grassland birds and how they are impacted by traffic noise.
For more information about the NSNSD, click here.
Posted on Oct. 28, 2014 by Taylor Jaquez
New study verifies more than 100,000 elephants in Africa killed in three years
New research led by Colorado State University has revealed that an estimated 100,000 elephants in Africa were killed for their ivory between 2010 and 2012. The study shows these losses are driving population declines of the world's wild African elephants on the order of 2 percent to 3 percent a year.
Landmark Analysis of Continent-Wide Poaching TollThis study provides the first verifiable estimation of the impacts of the ongoing ivory crisis on Africa’s elephant populations to date, solidifying speculation about the scale of the ivory crisis. An average of 33,630 elephants per annum are calculated to have been lost over those three years, with preliminary data indicating unsustainable levels continued in 2013.
To quantify the poaching death toll, researchers drew on data and experience from a continent-wide intensive monitoring program. The most thoroughly studied site was Samburu in northern Kenya where every elephant birth and death over the past 16 years has been recorded. The intensive population study was conducted in a project founded by George Wittemyer of Colorado State University with Save the Elephants, and in association with the Kenya Wildlife Service.
Wittemyer is lead author of the new report and a professor in the Department of Fish, Wildlife and Conservation Biology at CSU’s Warner College of Natural Resources. He has dedicated his scientific career to understanding and conserving one of Earth’s most intelligent and charismatic species.
"Witnessing the killing of known elephants, some that we have followed since they were born, has been terrible," said Wittemyer. "Our data has become the most sensitive barometer of change during this poaching epidemic. We needed to quantify the scale of killing and figure out how to derive rigorous interpretation of poaching rates."
Quantifying the scale of killing
The team used the intensive study of the Samburu elephants as a Rosetta stone to translate less detailed information from 45 elephant populations across Africa to estimate natural mortality and illegal killing rates to model population trends for the species. The UN-mandated continental Monitoring of Illegal Killing of Elephants (MIKE) programme establishes cause of death for each elephant carcass found in these sites, and this has provided the best measure of poaching pressure.
Species DeclineOver the last decade, the proportion of illegally killed elephants has climbed from 25 percent to between 60 percent and 70 percent. Such figures cause conservationists alarm, as the study shows over 54 percent is a level of poaching that elephant birth rates are unable to overcome and will lead to population decline.
”This study helps make sense of the challenge faced by thousands of rangers working on the frontlines to protect elephants and other species across Africa,” said co-author Julian Blanc of the Convention on the International Trade in Endangered Species (CITES) secretariat. “It also highlights the importance of the accurate collection of data as part of their day-to-day patrol work, which is essential to understand and communicate the true proportions of the threat that elephants face.”
To establish figures rather than proportions, two types of model were used. One focused on the elephant populations with the best information and used them as an indicator for the conditions in their region of Africa. The other used proxy variables such as Chinese consumption rates and a corruption index to estimate illegal killing in 300 sites. Both came to similar conclusions.
While the timing and magnitude of declines differed by region in Africa, with central Africa experiencing the worst levels, all regions of Africa are facing unsustainable levels of ivory poaching with the killing peak in 2011 equating to more than 40,000 elephant deaths.
“It's a complex situation for elephants across Africa, with some populations – such as in Botswana – still increasing. History has taught us that numbers alone are no defense against attrition from the ivory trade, and this new work confirms that elephant numbers are decreasing in East, Central and Southern Africa,” said co-author Iain Douglas-Hamilton, founder of Save the Elephants.
The research paper, "Illegal killing for ivory drives global decline in African elephants," is published in the Proceedings of the National Academy of Sciences of the United States.
Traffic noise affects prairie dogs
Prairie dogs are a crucial component of the American prairie and necessary for a healthy ecosystem, but are commonly overlooked from a conservation perspective. They are considered highly tolerant of non-lethal human activities, but have suffered huge declines due to habitat loss, poisoning, shooting and disease outbreaks. The prairie dog is a keystone species whose survival is crucial for other prairie species, like the endangered black-footed ferret.
The team conducted research on rural prairie dog populations in Colorado, and utilized audio playback experiments to simulate colony exposure to highway traffic noise and isolate the impacts. The study was published in Animal Behaviour, and provides the first experimental evidence that noise from road traffic can degrade habitat and impact the behavior of this keystone species.
“Over the next 40 years, road travel is set to double worldwide. The effects on biodiversity from this expansion are likely to be substantial, and it is crucial that we are able to quantify the behavioral and fitness costs of different road-related disturbance factors, such as noise, in order to design and implement effective mitigation measures,” said Graeme Shannon, a Postdoctoral wildlife ecologist in CSU’s Warner College of Natural Resources and the paper’s lead author.
The study found that the exposure to noise causes behaviors similar to those that would be experienced with elevated risk of predation, for example, reduced foraging and increased alertness. However, there is also the possibility that vocal signals used to alert other prairie dogs to approaching threats may be masked by the traffic noise. “It’s very similar to when we try to conduct a conversation alongside a busy street - it can be difficult to hear what the other person is saying,” Shannon explained.
Prairie dogs make good subject animals because they live in high density colonies and are cognitively advanced. They are social creatures that use complex vocal communication, so the findings could lead to future discoveries with other social species.
“The fact that we found significant changes in their behavior has implications for this species and also more disturbance sensitive animals that may be ultimately lost from habitats that get too noisy,” Shannon said. “Our findings have global implications as road traffic and construction increases worldwide.”
Technology solutions for wildlife conservation: How GPS and cell phones are helping to monitor and protect African elephants
The viral spread of smartphones has jumped a species. African elephants are now also benefiting, thanks to new software algorithms developed by researchers and conservationists at the University of British Columbia, Vancouver, Colorado State University’s Warner College of Natural Resources, U.S. and Save the Elephants, Kenya.
New StudyA study co-authored by George Wittemyer, a leading elephant conservation biologist and professor in the Department of Fish, Wildlife, and Conservation Biology at CSU, was published in the journal Ecological Applications and reports on the use of advanced technology that will help monitor and protect African elephants.
The sophisticated tracking system collects, analyzes and reports on the movements and activities of nearly 100 African elephants in real-time in an effort to both understand the ecology of movement and also to protect these threatened animals.
“GPS, GSM and satellite phone technologies are rapidly becoming the pen and paper of animal field biologists,” says Jake Wall, the study’s lead author. “The GPS trail of an animal, combined with data from satellite imagery and other remote sensors, can give us a detailed picture of where the animal is, what it is doing and what it might be experiencing.”
The tracking system was developed using Geographical Information System (GIS) software components donated by the Environmental Systems Research Institute (Esri) in California, runs from the Amazon EC2 Cloud – the same cloud servers that power Netflix, and allows real time visualization of animal movements on Google Earth.
The technology provides near instantaneous observation of the GPS location of an animal within seconds of it being recorded by an animal's tracking collar. Data are transmitted via the Inmarsat satellite constellation or the local cell phone network.
The real-time locations reveal patterns of movement while high-resolution satellite imagery provides context for understanding observed behavior.
Behind the scenes, a set of sophisticated software algorithms monitor incoming elephant movement datastreams and summarize complex information. One algorithm looks specifically for elephants that become unnaturally immobile – a warning that can indicate that an elephant is in trouble.