# Identifying endangered species from footprints

> Can a photo of a footprint tell you which tiger made it? Inspired by expert trackers in Africa, the founders of WildTrack built the footprint identification technique (FIT), which measures more than 120 features of each footprint to identify species, individuals, sex and age-class, with accuracy above 90%. This short article explains how it works, from Amur tigers in China’s snow to rhinos, cheetahs and polar bears.

Summary by Kersey Lawrence, Original Wisdom. Updated 9 November 2026. Page: https://www.originalwisdom.com/tracking-literature/2013-jewell-alibhai-identifying-endangered-species-footprints/

## Citation and access

- **Authors:** Zoe Jewell and Sky Alibhai
- **Year published:** 2013
- **Journal or source:** SPIE Newsroom
- **Full citation:** Jewell, Z. and Alibhai, S. 2013. Identifying endangered species from footprints. SPIE Newsroom, 4 January 2013. doi:10.1117/2.1201212.004636.
- **DOI:** 10.1117/2.1201212.004636
- **Access status:** Hosted (freely available elsewhere)
- **PDF:** https://www.originalwisdom.com/wp-content/uploads/2026/11/2013_Jewell_and_Alibhai_identifying-endangered-species-from-footprints.pdf

## Tags

- **Species:** Mammals > Baird’s tapir; Mammals > Black rhinoceros; Mammals > Cheetah; Mammals > Lowland tapir; Mammals > Mountain lion; Mammals > Polar bear; Mammals > Tiger; Mammals > White rhinoceros
- **Region:** Asia > China
- **Tracking:** Individual identification; Snow tracks; Track measurements; Track photographs; Tracking; Tracks; Tracks and signs identification
- **Methods and technology:** Footprint Identification Technology (FIT); Global Positioning System (GPS)
- **Data type:** Review
- **Observer qualification:** Not needed
- **Discipline:** Wildlife tracking
- **Year published:** 2013

## Detailed keywords

- **Species:** Main example: Amur tiger (left hind footprints in snow and other substrates; captive and free-ranging animals tracked in northeast China). The footprint identification technique (FIT) has also been adapted for black rhino, white rhino, Bengal tiger, polar bear, cougar (mountain lion), cheetah, Baird’s tapir, lowland tapir and several small mammals at species level. No scientific names are given in the article text (black rhino, Diceros bicornis, and white rhino, Ceratotherium simum, appear only in the titles of cited references).
- **Location and habitat:** Amur tigers tracked in northeast China. The authors worked for many years with expert trackers in Africa (no country named). Authors based at WildTrack, Durham, North Carolina, United States; visiting scientists at JMP (SAS Institute, Cary, North Carolina) and Duke University. Footprints in different substrates, including snow.
- **Topics:** footprint identification technique (FIT); non-invasive monitoring of endangered species; identifying species, individuals, sex and age-class from footprints; standardized photo protocol; anatomical landmarks; training sets from captive animals applied to free-ranging populations; drawbacks of telemetry collars (stress, altered behaviour, reduced female fertility); comparison with camera traps, vocal and coat patterns, and DNA from faeces and hair; community involvement; automated feature extraction (structured lighting, polynomial texture mapping, invariant moments, Kinect depth camera); FIT v.1 software in JMP; learning from expert trackers.
- **Statistics or models:** More than 120 measurements (areas, lengths and angles) per footprint, taken by a JMP script; stepwise variable selection; cross-validated pairwise discriminant analysis with Ward’s clustering, shown as a cluster dendrogram (tree diagram) for individual identification; discriminant analysis for sex, age-class and species. Accuracy reported as greater than 90%.
- **Data type:** Review: a short, three-page overview of the authors’ own technique in a science news magazine (SPIE Newsroom). No new data or sample sizes are reported; details are in the cited white rhino paper (Alibhai, Jewell and Law 2008). The PDF carries a 2012 copyright and the DOI code 2.1201212 (December 2012 issue); Crossref gives online publication on 4 January 2013.

## Synopsis

### 1. What they did

The authors argue that conservation needs monitoring methods that are cheap, non-invasive and friendly to local communities. Fitting animals with telemetry devices can cause stress, change behaviour and reduce female fertility, and it is costly and rarely involves local people. Camera traps, vocal and coat patterns, and DNA from faeces and hair all help identify individuals, but each can be limited in range, accuracy or cost. Footprints, by contrast, are everywhere on suitable ground, cheap to collect and can be good biometric markers.

After many years working with expert trackers in Africa and seeing how accurately they identified individual animals from footprints along trails, the authors set out to turn those skills into a modern tool. In this short article they describe their footprint identification technique (FIT):

- Photographing. A series of digital images is taken along several trails, following a standardized photo protocol. A metric ruler is placed along the bottom and left side of the footprint, with a slip recording the Global Positioning System (GPS) position, date, photographer and track number.

- Measuring. Each image is imported into JMP software (SAS Institute) and landmarks are placed by hand at specific anatomical points. A script then takes more than 120 measurements of areas, lengths and angles.

- Analysing. The measurements that classify best are picked out by stepwise selection. Trails are compared with a cross-validated pairwise discriminant analysis and Ward’s clustering, which shows individuals as a tree diagram.

- Training and applying. For each species, an algorithm is first built from a training set of footprints from captive animals, then applied to a free-ranging population.

### 2. What they found

- Every species has its own footprint anatomy, and every individual of a species has its own footprint. Each footprint an individual makes also differs, with the substrate, gait, weather and terrain, so a model has to keep variation within one animal small and variation between animals large.

- FIT gives accuracy rates of greater than 90% in telling species, sex and age-class apart. The article gives no sample sizes; it refers to the authors’ earlier white rhino paper for details.

- Large, well-checked training sets, tested on subsets of known free-ranging individuals, show the technique can identify wild as well as captive animals.

- FIT has been adapted for black and white rhino, Amur and Bengal tiger, polar bear, cougar, cheetah, Baird’s and lowland tapir, and several small mammals at species level. A short video shows footprints being collected from captive and free-ranging Amur tigers in northeast China.

- Placing landmarks by hand, by an expert, is still the most accurate way to classify individuals, as in medical imaging. Automated methods (structured lighting, polynomial texture mapping and invariant moments) have yet to match it.

### 3. What they concluded

- The authors were writing the first general release of FIT software in JMP (FIT v.1), with variable extraction, data analysis and mapping, as a complete tool for biologists monitoring endangered species.

- They are still looking for automated feature extraction that is accurate, cost-effective and works in the field. With North Carolina State University and Tom Malzbender, they are testing a Kinect motion sensor camera, possibly with structured lighting, to make a depth map of footprints.

- Their aim is a fast, cheap, reliable and user-friendly tool for conservationists to monitor endangered species from footprints.

- They close by saying they remain humbled by the extraordinary tracking skills that evolved with our ancestors thousands of years ago.

### 4. How tracking was or was not used

FIT is built on footprints: photographing footprints along trails, often in snow, and measuring them to identify species, individuals, sex and age-class. The authors say the method was inspired by expert trackers in Africa whom they watched identify individuals from footprints along trails in the bush. No trailing (following tracks to find an animal) is described.

### 5. Tracker or observer certification

Not reported. The article does not say who found and photographed the footprints or who placed the landmarks, although it stresses that the accuracy of the method depends on expert landmark placement. The African trackers who inspired the work are called expert, but they are not named and their skill was not tested here.

### 6. Other technologies, skills or innovations

- Standardized footprint photo protocol with a metric ruler and an information slip (GPS position, date, photographer, track number).

- JMP software (SAS Institute) with a script that takes more than 120 measurements per footprint; FIT v.1 software in development.

- Possible automated methods: structured lighting, polynomial texture mapping, invariant moments, and a Kinect motion sensor camera making depth maps.

### 7. Implications for conservation (from the paper)

- Conservation needs low-cost, non-invasive, community-friendly monitoring, without the harm that collars and capture can cause.

- Footprints are everywhere, cheap to collect and can identify individuals, so they can give reliable data on endangered populations and individuals.

- Local communities’ commitment is essential to conservation, and invasive methods rarely involve them.

### 8. Implications for tracking (Original Wisdom's observations)

_These are Original Wisdom's observations, not the authors'._

- The technique openly starts from trackers’ skill: the authors set out to translate what expert trackers already do, identify individuals from their footprints, into a measurable, repeatable method.

- The authors note that each footprint changes with substrate, gait, weather and terrain. Trackers deal with this variation every day, and it is the main challenge any footprint-based identification has to solve.

## Cite this summary

Lawrence, K. 2026. Summary of: Identifying endangered species from footprints (Jewell and Alibhai, 2013). Original Wisdom, Tracking Literature. https://www.originalwisdom.com/tracking-literature/2013-jewell-alibhai-identifying-endangered-species-footprints/