Submitted:
04 August 2025
Posted:
05 August 2025
Read the latest preprint version here
Abstract
Keywords:
1. Introduction
2. Materials and Methods
2.1. Study Area
2.2. Experimental Design
2.3. Wolf-Deterrent Collar
2.4. Retrospective and Progressive Data Comparison and Analysis
2.5. Camera Trapping
3. Results
3.1. Predation Events in the Three Trail Groups


3.2. Retrospective Analysis of Predation Losses (2020–2024)
3.3. Camera Trap Monitoring of Wolf Activity
4. Discussion
4.1. Environmental Influences on Acoustic Deterrent Performance
4.2. Efficacy of Combined Protective Strategies
4.3. Perspectives and Work in Progress
5. Conclusions
Supplementary Materials
Ethical Considerations
Acknowledgments
Conflicts of Interest
Abbreviations
| FP1 | Camera Traps 1 |
| FP2 | Camera Traps 2 |
| PC | Group Experienced Herder Only |
| PCG | Group Herder and Guardian Dogs |
| PCGC | Group Herder + Guardian Dogs + Anti-Wolf Collar |
Appendix A
Appendix A.1
| Parameter | Value / Range | Notes |
|---|---|---|
| Elevation | 200 m a.s.l. | According to Italian Geographic Military Institute (2023) |
| Coordinates | 37°57′01″ N, 15°56′37″ E | WGS84 system |
| Climate type | Mediterranean | Hot, dry summers; mild, wet winters |
| Annual mean temperature | 9 °C to 31 °C | Peaks ~34 °C in summer, rarely <6 °C in winter |
| Annual precipitation | ≈ 545 mm | Mostly concentrated in winter months |
| Warm season | mid-June to mid-September | Daily mean temperatures >28 °C |
| Cool season | late November to early April | Mean temperatures <18 °C |
| Peak solar radiation | July | Clear/partly cloudy skies ~96% of the time |
| Average wind speed | 13–21 km/h | Seasonal variability can affect sound propagation |
| Relative humidity | Variable | Seasonally dependent; relevant for acoustic systems |
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| Feature / Parameter |
Wolf (Canis lupus) | Dog (Canis lupus familiaris) |
Livestock (sheep, goats, cattle, horses) |
|---|---|---|---|
| Hearing range (Hz) | ~150–45,000 Hz (up to ~80,000 Hz in some sources) [36,40] | ~67–45,000 Hz [37] | ~23–40,000 Hz, depending on species [38,39] |
| Peak sensitivity (Hz) | ~2,000–8,000 Hz (behaviorally); ~40,000–80,000 Hz (physiologically) [40] | ~2,000–8,000 Hz (behaviorally); ~1,000–20,000 Hz [37] | ~8,000–10,000 Hz (sheep/goats: ~10 kHz; cattle: ~8 kHz); ~1,000–8,000 Hz [38] |
| Ultrasound detection | Excellent; highly sensitive to ultrasonic range (up to 80 kHz) [36] | High; upper limit ~60 kHz [37] | Poor above ~20 kHz; limited response near 30–40 kHz [39] |
| Sensitivity level | Very high; adapted for long-distance detection and hunting | High, but variable across breed, age, and training | Moderate; suited to mid-frequency group alertness |
| Communication frequencies | ~150–780 Hz (howls) with higher harmonics [41] | Wide repertoire: barking, whining, growling [37] | Mostly low-frequency vocalizations: bleats, moos, neighs [40] |
| Functional implication | Detection of prey, predators, and conspecific calls; social communication | Responsive to human cues and high-frequency commands | Adapted for herd alertness; limited reliance on high-frequency acoustic signals |
| Adaptation | Wild hunter: optimized for survival, navigation, and territorial vocalizations | Domestic adaptation: tuned to canine–human communication | Domesticated herd species: optimized for inter-individual contact and predator detection |
| Components | Technical and Functional Specifications |
|---|---|
| Collar Material | Technical plastic filaments (high thermal and mechanical resistance, low conductivity) |
| Manufacturing Technology | 3D printing |
| Speakers | 2 piezoelectric POFET, 30 Vp-p, range 2.5 Hz–60 kHz, 14.07 watts |
| Generator Module | Kemo M048N, adjustable 7–40 kHz, max intensity 110 dB |
| Operating Frequency | 2.5 Hz–40 kHz |
| Power Supply Module | 12 V solar panel (1.5 W) + 150 Ah rechargeable lithium-ion battery |
| Energy Autonomy | 12 hours per day, up to 4 days without solar irradiation |
| Effective Range | Approximate useful radius of 50–100 meters, corresponding to 7,850–31,400 m2 (variable based on topography, morphology, and climate) |
| Emission System | Modulated intervals of frequencies based on natural harmonic sounds |
| Group | Livestock Category |
Month | Attacks | Prey | FP1(photos) | FP2 (photos) | Total Photos | Observations |
|---|---|---|---|---|---|---|---|---|
| PC | Goats | June | 21 | 5 | 6 | 5 | 11 | Constant nocturnal presence |
| PC | Goats | July | 24 | – | 4 | 6 | 10 | Filmed episode |
| PC | Goats | August | 27 | – | 8 | 3 | 11 | Constant nocturnal presence |
| PCG | Goats | June | 11 | 1 | 5 | 4 | 9 | Wolf passages |
| PCG | Goats | July | 17 | – | 7 | 6 | 13 | Increased activity at dusk |
| PCG | Goats | August | 25 | – | 6 | 4 | 10 | Observed pair movement |
| PCGC | Goats | June | 0 | 0 | 7 | 4 | 11 | Constant nocturnal presence |
| PCGC | Goats | July | 1 | – | 6 | 5 | 11 | Presence confirmed by video |
| PCGC | Goats | August | 0 | – | 5 | 5 | 10 | Observed pair movement |
| Year | Goats on Farm | Goats Predated by Wolf | Percentage | Total Stock |
|---|---|---|---|---|
| 2020 | 97 | 16 | 16 % | 81 |
| 2021 | 101 | 11 | 10 % | 98 |
| 2022 | 137 | 27 | 19 % | 110 |
| 2023 | 236 | 39 | 16 % | 197 |
| 2024 | 205 | 55 | 26 % | 150 |
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