# Individual, Sexual, Seasonal, and Temporal Variation in the Amount of Sagebrush Lizard Scent Marks

> Shine a black light on a lizard’s favourite basking rock and its scent marks glow. Researchers collected the marks of 131 captive sagebrush lizards daily over 56 days and found that how much scent a lizard leaves says little about who it is, but a lot about its size, condition and breeding state. The lizards also seemed to top up their marks on a roughly weekly cycle.

Summary by Kersey Lawrence, Original Wisdom. Updated 9 November 2026. Page: https://www.originalwisdom.com/tracking-literature/2006-martins-ord-individual-sexual-seasonal-temporal/

## Citation and access

- **Authors:** E. P. Martins, T. J. Ord, J. Slaven, J. L. Wright and E. A. Housworth
- **Year published:** 2006
- **Journal or source:** Journal of Chemical Ecology
- **Full citation:** Martins, E. P., Ord, T. J., Slaven, J., Wright, J. L. and Housworth, E. A. 2006. Individual, sexual, seasonal, and temporal variation in the amount of sagebrush lizard scent marks. Journal of Chemical Ecology 32(4): 881–893.
- **DOI:** 10.1007/s10886-006-9029-8
- **Access status:** Hosted (freely available elsewhere)
- **PDF:** https://www.originalwisdom.com/wp-content/uploads/2026/11/2006_Martins_and_Ord_etal_individual-sexual-seasonal-and-temporal-variation-in-the-amount-of-sagebrush-lizard-scent-marks.pdf

## Tags

- **Species:** Reptiles > Sagebrush lizard
- **Region:** North America > United States
- **Behaviour and ecology:** Behaviour; Communication
- **Methods and technology:** Pearson correlation
- **Data type:** New field data
- **Observer qualification:** Not needed
- **Discipline:** Behaviour and ecology
- **Year published:** 2006

## Detailed keywords

- **Species:** Studied: sagebrush lizard (Sceloporus graciosus), 82 adult males and 49 adult females. Food given in captivity: mealworms and vitamin-enriched crickets. Other species mentioned from the literature only: green iguana (Iguana iguana), whiptail lizards (Cnemidophorus uniparens), tree lizard (Urosaurus ornatus), sleepy lizard, voles and other rodents.
- **Location and habitat:** Lizards caught near Wrightwood, southern California, United States (34°23’30”N, 117°42’W), in May 2002 and May 2003. The study itself was done in a laboratory colony at Indiana University, Bloomington, Indiana, in aquaria with sand and a split-level brick basking perch; some animals spent June to September in outdoor enclosures before the experiment.
- **Topics:** scent marking; chemical signals; femoral pores and femoral pore secretions; fecal spots (droppings) as possible chemical signals; ultraviolet (UV) reflective scent marks seen under black light; individual and sex identity; physiological condition and body size; reproductive state; territorial season versus mating season; hibernation; time in captivity; weekly cycle of scent-mark renewal; territorial defence; marking more sites rather than marking one site more heavily.
- **Statistics or models:** generalized linear mixed models (GLMMs, SAS GLIMMIX procedure) with a negative binomial distribution and log link for spot number and a lognormal distribution for spot area; type III sums of squares; Pearson product-moment correlations (within seasons and between seasons, as repeatability); time series analysis with autocorrelation functions; first-order autoregressive model chosen by the Bayesian Information Criterion (BIC). Inconsistencies in the paper: (1) the text says animals in captivity for more than a year made fewer but larger femoral pore spots, but Table 1 codes 17 months as 0 and 5 months as 1, so its predicted effects (23% fewer, larger spots) would apply to the 5-month animals; (2) the text refers to Table 2 for the type III GLMM results, which are in Table 1; (3) the methods give individual codes for 128 animals, while 131 lizards (82 males and 49 females) are listed; (4) Table 1’s caption says “general linear mixed models” while the text says generalized linear mixed models; (5) Figure 2B gives r = 0.4, P < 0.05 for fecal spot size across seasons, while Table 2 gives r = 0.39, P < 0.01.
- **Data type:** New experimental data from captive lizards (a laboratory study, not field data), collected daily from 13 October to 16 November 2003 (35 days before hibernation, the territorial season) and from 26 January to 15 February 2004 (21 days after hibernation, the early mating season).

## Synopsis

### 1. What they did

Many animals leave scent marks, but most studies of how much scent animals leave, and when, have been done on rodents. The authors studied the sagebrush lizard, a small, territorial lizard of the western United States. Like many lizards, they have femoral pores, glands that release a chemical secretion. The authors asked whether the amount of secretion a lizard leaves on its favourite perch tells others who it is (which individual, which sex), or rather how it is doing (body size, condition and breeding state).

- The lizards. 82 males and 49 females caught near Wrightwood in southern California in May 2002 and May 2003 were kept in a laboratory colony at Indiana University. Each lived alone in an aquarium with a brick basking perch under a heat lamp. One group had been in captivity for 17 months, the other for 5 months, at the time of the study.

- Collecting the marks. A white paper towel was taped to the top of each brick and changed every day. Under a black light, femoral pore spots glow (they reflect ultraviolet light) while fecal spots do not, so the two could be told apart. Every spot was counted and its diameter measured to the nearest 0.5 mm, and the total area per lizard per day was calculated.

- Two seasons. Data were collected daily for 35 days before hibernation (October to November 2003, a season when both sexes defend territories) and for 21 days after hibernation (January to February 2004, the early mating season).

- Analysis. They tested which factors explained the number and size of femoral pore spots: individual, sex, season, body size, weight and time in captivity. They checked whether the same lizards marked heavily in both seasons, and looked for a rhythm in marking over the 56 days.

### 2. What they found

How much they marked

- Every lizard left femoral pore spots on at least one day before hibernation, but 10 males and 5 females left none after hibernation.

- Lizards left 0 to 11 femoral pore spots a day, and most marked the brick on fewer than 30% of days. Most spots were under 3 mm² in area, a few up to 18 mm². Fecal spots were sometimes larger, up to 40 mm².

What explained the amount

- Condition mattered more than identity or sex. In the mating season, lizards left about 20% fewer femoral pore spots than in the territorial season, though the spots were slightly larger.

- Longer lizards (snout-to-vent length) left fewer, but not smaller, spots. Weight did not predict marking.

- Time in captivity had a strong effect. The text reports that lizards held for more than a year left fewer but larger spots than those held for 5 months; the table’s coding suggests the opposite direction (see keywords).

- Surprisingly, males and females did not differ, even though males have visibly larger femoral pores, especially in the mating season.

- Lizards that left more fecal spots also left more femoral pore spots.

Not a signature of the individual

- Lizards that marked a lot in the territorial season were not the same ones that marked a lot in the mating season. Only fecal spot size was linked across seasons, and that seemed to be driven by an outlier.

A weekly rhythm

- Averaged over all lizards, the number of spots rose and fell on a roughly weekly cycle, for both femoral pore and fecal spots, with the fecal pattern weaker.

- Lizards seemed more in step with each other after hibernation, when the number of femoral pore spots and fecal spots on each day were also more closely linked.

### 3. What they concluded

- The amount of scent a lizard leaves on one perch carries little information about which individual or which sex it is. That information is more likely carried by the chemical make-up of the secretion, which other studies show differs between individuals, sexes, populations and species.

- Instead, the amount reflects body size, condition and breeding state, and so may help other lizards make decisions about mates and territory.

- The roughly weekly cycle suggests marks are topped up regularly, so how fresh a mark is may tell others how active the resident is. The authors note that lizards might even see the marks from a distance, as well as smell them.

- Breeding males are known to produce more secretion, yet here they left less on one perch. The authors suggest that in the wild, extra secretion in the mating season is used to mark more places (males defend several perches then), rather than marking one place more heavily.

- Playback experiments and studies of how fast marks fade are needed to test whether lizards actually read this information.

### 6. Other technologies, skills or innovations

- Paper towels changed daily on a single preferred perch, giving a simple, repeatable daily record of scent marks and droppings.

- Black (ultraviolet) light to make femoral pore secretions visible and separate them from fecal spots.

- Time series analysis to find a rhythm in marking behaviour.

## Cite this summary

Lawrence, K. 2026. Summary of: Individual, Sexual, Seasonal, and Temporal Variation in the Amount of Sagebrush Lizard Scent Marks (Martins and Ord et al., 2006). Original Wisdom, Tracking Literature. https://www.originalwisdom.com/tracking-literature/2006-martins-ord-individual-sexual-seasonal-temporal/