# Hind Foot Length: An Indicator for Monitoring Roe Deer Populations at a Landscape Scale

> Can a deer’s foot tell you how crowded the forest is? Over 13 years, hunters in southwestern France sent in the hind feet of nearly 29,000 roe deer. Fawns grew shorter feet in years when deer were more plentiful, offering managers a cheap way to follow how a population is faring across a whole landscape.

Summary by Kersey Lawrence, Original Wisdom. Updated 9 November 2026. Page: https://www.originalwisdom.com/tracking-literature/2006-zannese-baisse-hind-foot-length-indicator/

## Citation and access

- **Authors:** Audrey Zannèse, Alain Baïsse, Jean-Michel Gaillard, A. J. Mark Hewison, Karine Saint-Hilaire, Carole Toïgo, Guy Van Laere and Nicolas Morellet
- **Year published:** 2006
- **Journal or source:** Wildlife Society Bulletin
- **Full citation:** Zannèse, A., Baïsse, A., Gaillard, J.-M., Hewison, A. J. M., Saint-Hilaire, K., Toïgo, C., Van Laere, G. and Morellet, N. 2006. Hind foot length: an indicator for monitoring roe deer populations at a landscape scale. Wildlife Society Bulletin 34(2): 351-358.
- **DOI:** 10.2193/0091-7648(2006)34[351:HFLAIF]2.0.CO;2
- **Access status:** Publisher link only
- **Where to find it:** https://doi.org/10.2193/0091-7648(2006)34%5B351:HFLAIF%5D2.0.CO;2

## Tags

- **Species:** Mammals > Roe deer
- **Region:** Europe > France
- **Methods and technology:** Analysis of covariance (ANCOVA); Linear regression; Population trends
- **Data type:** New field data
- **Observer qualification:** Not needed
- **Discipline:** Behaviour and ecology; Just interesting; Population trends
- **Year published:** 2006

## Detailed keywords

- **Species:** Studied: roe deer (Capreolus capreolus), fawns under one year old shot by hunters. In the study area but not studied: wild boar (Sus scrofa) across the whole province, and red deer (Cervus elaphus) in region 1 only. Mentioned from other studies: reindeer and caribou (Rangifer tarandus), white-tailed deer (Odocoileus virginianus borealis), alpine ibex.
- **Location and habitat:** Tarn province (département), southwestern France, 5,796 km², mostly hills and valleys with mountains up to 1,300 m in the southeast. Oceanic climate with some Mediterranean influence. Region 1 (576 km², north and northwest): deciduous forest of oak, chestnut and beech. Region 2 (3,408 km², centre): farmed and urbanised land with little woodland. Region 3 (1,812 km², southeast): mountainous mixed forest of oak, chestnut, Norway spruce, Douglas-fir and true fir; the wettest and coolest region. Background data from the enclosed Chizé Reserve, western France.
- **Topics:** ecological indicators; density dependence; body size and skeletal growth of fawns; hind foot length; population monitoring at a landscape scale; hunting bag records as a density index; hunting quotas; spring and summer climate (hydric index); habitat quality; sex differences in body size; ageing fawns by the cartilage on the metatarsus; regional differences between forest, farmland and mountain deer; wildlife management.
- **Statistics or models:** Analysis of covariance (ANCOVA) for each region; linear regressions of hind foot length on date of shooting, used to adjust every measurement to 15 November; a hydric index (average precipitation minus twice the mean temperature) for spring (April and May) and summer (June and July); index of density = roe deer shot per km² per year; comparison of a low-density period (1993 to 1997) with a high-density period (1998 to 2002). Software: SPSS 11.5 and R 2.0.1. Significance at P < 0.05. Inconsistencies: (1) the yearly means in the text (for example region 1, 317.6 mm in 1993 to 310.2 mm in 2002) are about 5 mm lower than the values plotted in Figure 3, which may show unadjusted values; (2) Figure 4 shows far higher shot-deer densities for regions 2 and 3 (about 1.2 and 2.7 shot roe deer per km² in 1998 to 2002) than the period means given in the text (0.31 and 1.53) and the axes of Figure 5; (3) the Discussion says hind foot length was lower after cool, wet springs in regions 2 and 3 for males, but in region 3 the Results report only a non-significant trend (P = 0.055).
- **Data type:** New field data: left hind feet and report cards of all roe deer legally shot in the Tarn, collected by the Tarn Hunter Federation from 1990 to 2002 (28,761 deer, 10,160 classed as fawns; 9,770 fawns from 1993 to 2002 used in the main analysis). Monthly weather data from three Météo France stations. Unpublished capture-mark-recapture data from Chizé (1987 to 2003) cited as background.

## Synopsis

### 1. What they did

Roe deer live in forest and are hard to count, and counts are often wrong. Wildlife managers in France therefore use indicators that show how well a deer population is matched to its food and habitat. Many of these were designed for small areas of a few thousand hectares. The authors asked whether a simple body measurement, the hind foot length of fawns, could track the balance between deer numbers and their environment across a whole province.

The idea is that a deer’s hind foot grows fast after birth and stops growing early, so the length of a fawn’s foot should reflect the conditions the fawn grew up in. In the fenced Chizé Reserve, where deer numbers are well known, fawn hind foot length had already been found to fall as density rose.

- Collecting the feet. From 1990 to 2002, hunters in the Tarn province of southwestern France sent in the left hind foot of every roe deer legally shot (28,761 deer), with a card giving sex, estimated age (fawn or adult), and place and date of death. From 1996 onwards, age was checked by looking for a layer of cartilage at the end of the foot bone that only fawns have.

- Measuring. One experienced wildlife manager measured every foot with a wooden gauge, to the nearest millimetre, from the top of the heel bone (calcaneum) to the tip of the hoof.

- Dividing the province. They split the province into three regions by forest cover and altitude: deciduous forest in the north, farmland in the centre, and mountain mixed forest in the southeast.

- Density and climate. As a density index they used the number of roe deer shot per km² each year in each region, because no other reliable count existed. For climate they built a “hydric index” for spring and for summer, which rises when the season is wet and cool.

- Analysis. They analysed 9,770 fawns shot from 1993 to 2002, region by region. They corrected each foot length for the date it was shot, then tested whether yearly mean foot length was linked to density and to spring and summer climate. As a check, they also compared a low-density period (1993 to 1997) with a high-density period (1998 to 2002).

### 2. What they found

Basic patterns

- Fawns’ feet kept growing through the hunting season, by about 0.11 to 0.14 mm a day.

- Male fawns had slightly longer hind feet than females in all three regions, by about 3 to 4.5 mm.

- Foot length generally fell over the years in all three regions, with some ups and downs.

- The number of roe deer shot in the province rose from 373 to 4,999 a year. Shot-deer density rose from 1993 to 1999, then levelled off in region 2 and fell slightly in regions 1 and 3.

Density

- In the northern forest (region 1) and the mountain forest (region 3), fawns had shorter feet in years of higher density. In region 3, foot length fell by about 2.8 mm for each extra roe deer shot per km².

- In the farmland (region 2), where density was lowest, there was no clear link with density.

- Comparing the two periods gave the same picture: feet were 3.2 mm shorter in the high-density period in region 1 and 2.35 mm shorter in region 3, with no difference in region 2.

Climate

- Summer weather had no effect on foot length in any region.

- Cool, wet springs went with shorter feet in some cases: in region 2 for males only, with a weaker trend for males in region 3. In region 1, spring weather changed how strongly foot length responded to density; feet were most sensitive to density after dry, warm springs.

Regions

- The smallest fawns were in region 3, the mountainous, wettest and coolest region, which also had the highest density. The largest were in the farmland of region 2, which had the lowest density.

### 3. What they concluded

- Hind foot length of fawns is a useful indicator of density dependence in roe deer: it reflects how deer numbers relate to the food and habitat available, and can be used to follow population trends.

- The density index from hunting bags is only an approximation, but the authors are confident it reflects real trends, because the yearly figures and the two-period comparison gave the same results.

- The lack of a density effect in the farmland region may be because density there had not yet reached the level at which food becomes limiting.

- Indicators need to be followed over many years to show trends, and values should be compared over time within one area, not between areas, because each population responds to its own environment.

- Because males and females differ slightly, sex must be taken into account when comparing body measurements.

- A decline in foot length does not tell managers whether the cause is poorer habitat or more deer. The authors argue this matters less to a manager than having a reliable signal of density dependence.

### 6. Other technologies, skills or innovations

- Ageing by bone: the cartilage at the end of the metatarsus (the long foot bone) is present only in fawns and disappears at about 14 to 16 months, giving a reliable way to tell fawns from adults during the hunting season.

- A simple, cheap measurement: an experienced wildlife manager could measure about 150 hind feet in an hour with a wooden gauge.

- A forest cover index from a satellite image, smoothed over 1 km, used to map the regions.

- A hydric index (precipitation minus twice the temperature) as a stand-in for how much green food plants produce in spring and summer.

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

- Hunters across a whole province can collect hind feet easily, so the method gives information at a landscape scale, larger than the usual management units.

- Index methods like this are less time-consuming and costly than counting deer, and more useful for management decisions.

- Hind foot length should be monitored together with other indicators, such as the browsing index and the kilometric index (deer seen per kilometre walked), to give a full picture of a roe deer population and its environment.

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

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

- The study measured the bony hind foot of shot deer, not footprints, but it shows that foot size within one population changes with sex, age within the first year, local density, spring weather and region. Trackers who use track size to judge the sex, age or identity of deer may find it useful to keep this natural variation in mind.

## Cite this summary

Lawrence, K. 2026. Summary of: Hind Foot Length: An Indicator for Monitoring Roe Deer Populations at a Landscape Scale (Zannèse and Baïsse et al., 2006). Original Wisdom, Tracking Literature. https://www.originalwisdom.com/tracking-literature/2006-zannese-baisse-hind-foot-length-indicator/