The Use of Open Vegetation by Red Deer (Cervus elaphus) and Fallow Deer (Dama dama) Determined by Object Detection Models
Abstract
:1. Introduction
- The distribution of populations of red and fallow deer within Hanstholm Nature Reserve;
- Their preference for different natural vegetation types and habitat-related behaviour;
- The daily migration patterns of populations of red deer and fallow deer within Hanstholm Nature Reserve.
2. Materials and Methods
2.1. Study Area
2.2. Collection of Material and Data
2.3. Species Identification
2.4. Behaviour Classification
2.5. Data Analysis and Definition of Variables
2.5.1. Vegetation Type and State
2.5.2. Statistical Analysis
3. Results
3.1. Model Performance Metrics
3.2. Distribution of Red and Fallow Deer Within Study Area
3.3. Behaviour Proportions in Vegetation Types and Within Species
3.4. Behavioural Instability
3.5. Correlations of Vegetative State Data with Behaviour Proportions
4. Discussion
4.1. Methodological Considerations
4.2. Distribution of Red and Fallow Deer Within Hanstholm Nature Reserve and Their Use of Natural Vegetation
5. Conclusions
Author Contributions
Funding
Data Availability Statement
Conflicts of Interest
References
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Behaviour | Description |
---|---|
Foraging | Head of animal placed lower than shoulders |
Interacting | Head of one animal touching the body of another animal |
Locomoting | Animals moving |
Lying | Animals lying and limbs are not visible |
Standing | Animals standing upright and not moving |
Other | Other behaviours, transitioning from one behaviour to another or behaviour determination inconclusive |
Class | Images | Instances | mAP50 | mAP50−95 |
---|---|---|---|---|
All | 730 | 1430 | 0.664 | 0.516 |
Foraging | 225 | 489 | 0.841 | 0.686 |
Interacting | 6 | 6 | 0.259 | 0.183 |
Locomoting | 134 | 273 | 0.747 | 0.616 |
Lying | 72 | 132 | 0.821 | 0.624 |
Other | 77 | 118 | 0.528 | 0.340 |
Standing | 227 | 412 | 0.787 | 0.649 |
Vegetation Type | Red Deer (n) | Fallow Deer (n) | Total Area (km2) | Density of Red Deer (Individuals/km2) | Fallow Deer Density (Individuals/km2) |
---|---|---|---|---|---|
Grey dune | 11 | 3 | 0.7 | 55.5 | 5.4 |
Decalcified fixed dune | 46 | 12 | 3.2 | 85.2 | 6.6 |
Humid dune slacks | 30 | 15 | 3.6 | 92.7 | 8.2 |
Dunes with creeping willow | 16 | 7 | 1.7 | 22.4 | 5.6 |
Dunes with sea-buckthorn | 0 | 0 | 0.1 | 0 | 0 |
Semi-natural dry grasslands on calcareous substrates | 0 | 0 | 0.2 | 0 | 0 |
N/A | 51 | 1 | 2.0 | 271.0 | 1.0 |
Total | 154 | 39 | 11.4 |
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Jensen, L.L.; Pertoldi, C.; Pagh, S. The Use of Open Vegetation by Red Deer (Cervus elaphus) and Fallow Deer (Dama dama) Determined by Object Detection Models. Drones 2025, 9, 240. https://doi.org/10.3390/drones9040240
Jensen LL, Pertoldi C, Pagh S. The Use of Open Vegetation by Red Deer (Cervus elaphus) and Fallow Deer (Dama dama) Determined by Object Detection Models. Drones. 2025; 9(4):240. https://doi.org/10.3390/drones9040240
Chicago/Turabian StyleJensen, Lasse Lange, Cino Pertoldi, and Sussie Pagh. 2025. "The Use of Open Vegetation by Red Deer (Cervus elaphus) and Fallow Deer (Dama dama) Determined by Object Detection Models" Drones 9, no. 4: 240. https://doi.org/10.3390/drones9040240
APA StyleJensen, L. L., Pertoldi, C., & Pagh, S. (2025). The Use of Open Vegetation by Red Deer (Cervus elaphus) and Fallow Deer (Dama dama) Determined by Object Detection Models. Drones, 9(4), 240. https://doi.org/10.3390/drones9040240