BY JOSEPH BUMP
Photos courtesy of Voyageurs Wolf Project
More than 100 years ago, George Shiras III pioneered remote wildlife photography to capture night scenes of wildlife in Michigan’s Upper Peninsula. His innovative, ethereal images brought national recognition, and 74 of his photos were featured in the July 1906 issue of National Geographic–the first-ever wildlife photographs in the magazine. These days, wildlife photos are a staple between the covers of National Geographic, and remote cameras are a common, essential tool for wildlife professionals.
Shiras was the first to deploy trip wires to trigger cameras and flashes. When a passing animal triggered one of Shiras’ wires an explosion of magnesium powder flashed, and the shutter clicked on a camera set up on a nearby tripod. He was also one of the first to operate cameras at a distance via a string running from a blind or hide. Shiras, an attorney, patented his inventions in the United States and other countries and then dedicated their free use to the public to avoid commercial exploitation. Now at least 18 companies make remote cameras for a range of uses, from recreation to research.
Remote camera technology has moved well beyond the use of trip wires. Various sensors can trigger modern cameras using motion or heat, and researchers can choose nearly any setting: black and white, full color, high-definition video; multiple, rapid-fire pictures or timed delays between photos. Cameras with cellular network connections can transmit images immediately to researchers. Onboard memory cards can store thousands of images and hours of video, and artificial intelligence is increasingly used to evaluate images.
While the basic aim for these uses is the same as that of Shiras—to photograph or ‘camera trap’ wildlife to observe species—the capacity to record immense numbers of photographic observations is changing important aspects of biological research. Deploying dozens of cameras to record the presence of rare and endangered species is more efficient and effective than direct detection efforts like trapping. But wildlife researchers are using remote cameras in increasingly varied and creative ways.
For example, the world’s largest and most comprehensive camera-trap wildlife survey occurred in 2018-2019 when India’s National Tiger Conservation Authority and the Wildlife Institute of India placed remote cameras in 26,838 locations across 141 sites in India and surveyed an effective area of almost 47 thousand square miles. The cameras recorded nearly 35 million photographs of wildlife (76,651 of which were tigers and 51,777 were leopards; the remainder were other native fauna). From these photographs, 2,461 individual adult tigers were identified using tiger stripe-pattern-recognition software. As a result of the survey, it was concluded that India’s tiger population had increased by roughly one-third, from approximately 2,226 in 2014 to 2,927 in 2018. The increase may in part reflect more comprehensive surveying as opposed to purely population increase. Conclusions aside, the effort and data assessment would not have been possible without advances in remote camera technology and access.
Other notable examples of widescale camera surveys include Snapshot Safari, which aims to identify millions of wildlife caught on camera annually across sub-Saharan Africa. Closer to home, Snapshot Wisconsin uses more than 2000 cameras to monitor wildlife year-round using a statewide network of remote cameras. Both of these examples are projects that provide data needed for wildlife management decision making. They also offer opportunities for the public to participate in science through guided, online image classification and analysis. In this way, remote cameras are a tool that has significantly expanded opportunities for a diverse array of non-scientists to participate in wildlife monitoring.
In addition to increasing the extent of wildlife surveys and public participation in wildlife science, images from remote cameras are also leading to novel insights into animal behavior and species interactions. The peer-reviewed journal Food Webs recently launched a special collection of articles focused on the detection of novel species interactions directly from remote cameras. The reason for this special issue is that such natural history observations are helpful for generating new ideas and strengthening our understanding of food web ecology. Novel observations brought to light via remote cameras include scavenger interactions at elephant and marine mammal carcasses, acorn eating by owls, disease transmission risk across species at mineral licks, and how wolves hunt deer along linear features such as trails and paths. The insights presented in each of these papers would have been much harder to gain, if not impossible, without the use of remote cameras.
Voyageurs Wolf Project researchers use remote cameras to address a number of research and broader impact objectives. Remote cameras are critical to our goal of understanding changes in wolf population dynamics. The project currently maintains a year-round array of about 200 remote cameras in the Voyageurs region of northern Minnesota. Through painstaking viewing and sorting of high-definition video, we can estimate key parameters including pack size, pack composition and “recruitment” of wolf pups—the point in their development at which pups are deemed ready to run with the pack. Our goal during each annual survey is to record repeated independent observations of the same wolf pack. (We consider observations to be independent if they occur on different days.) Multiple independent observations of the same size for each pack provides reliable minimum pack-size estimates. A trained eye can also often distinguish between wolf age classes and track the number of pups present with packs across seasons. In doing so, analyses of pack composition, pup survival and recruitment are possible.
Audio visual footage captured with our remote camera array is also the primary content for our broader impacts campaign, generating critical content for our various social media platforms, with millions of viewers worldwide. Not everyone can experience Minnesota’s Northwoods, much less learn wolves’ natural history even if they do visit. The forests of northern Minnesota rarely allow for long sight lines, and wildlife viewing is a challenge, especially for most mammals. Remote cameras allow us to go “mammaling” in a way akin to the way binoculars enhance one’s ability to go birding. Indeed, camera trapping as a recreational pastime has grown exponentially over the past decade, increasing both individual connection to nature and insights valuable to wildlife science.
Even with the incredible gains that remote camera technology has made, fundamental and significant challenges remain and have emerged. Camera operation is still limited by battery life in most scenarios. Remote cameras are not yet efficient when it comes to energy consumption. We still need to spend thousands of dollars on increasingly expensive lithium batteries that operate well in frigid temperatures. In some environments solar power is an option, but such options remain peripheral to the camera unit and rarely employed.
Remote cameras can lead to too much of a good thing—massive amounts of imagery that requires special data storage and processing. Researchers working with camera-derived data quickly encountered data management and analysis challenges. Crowd-sourcing some image classification efforts has been hugely successful and is supported by outstanding platforms such as Zooniverse and CitSci. Still, tremendous progress is needed, and the cutting-edge work is exploring algorithms and artificial intelligence methods to identify and count animals recorded in remote camera images. These methods are also needed as they apply to video images.
On the Voyageurs Wolf Project we use remote cameras almost exclusively to record video. The data storage and video quality specifications of cameras continually improve; many can record in 4K high resolution now, and the need to efficiently process and analyze such data is tremendous.
Remote cameras create an exciting opportunity for researchers, community members, artists, computer scientists and others to work together—and we need creative teams to tackle and maximize the value of remote camera data.
Acknowledgment: The Voyageurs Wolf Project is especially grateful for the substantial funding and support provided by Minnesota Environment and Natural Resources Trust Fund as recommended by the Legislative-Citizen Commission on Minnesota Resources (LCCMR).
This article was originally published in the Winter 2023 edition of International Wolf magazine, which is published quarterly by the International Wolf Center. The magazine is mailed exclusively to members of the Center.
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Joseph Bump is a professor and the director of graduate studies in conservation and wildlife sciences at the University of Minnesota. He also teaches courses including Principles of Wildlife Management, Conservation Biology, Stable Isotope Ecology and Field Mammalogy.
