Research & Monitoring

What the Science Shows

Population Dynamics & Trends
Standardized territory mapping tracks singing males across the breeding season, providing long-term trend data while minimizing double-counting. Combined with distance sampling methods, this approach gives robust population estimates with confidence intervals -- critical for detecting real changes in this small population.

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Habitat Requirements
Multi-year vegetation studies reveal that Grenada Doves select dry forests with specific characteristics: over 50% canopy cover and key plant species including Haematoxylum campechianum (logwood), Bursera simaruba (gumbo limbo), and Leucaena leucocephala. These thorny legume forests provide both food resources and the structural complexity doves need for nesting and cover.

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Genetic Insights

DNA analysis from feather and blood samples reveals critically low genetic diversity—a warning sign for long-term population viability. Recent findings also show evidence consistent with male-biased sex ratios, which would depress effective population size and breeding potential even further.

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Population Viability Analysis
The latest modeling work (2023-2026) shows that extinction risk is highest in the west coast population. Risk increases sharply under scenarios of continued habitat loss (especially Mt. Hartman development), sex-ratio bias, and disease outbreaks. The models identify three management priorities:

• Habitat protection -- especially Mt. Hartman, the population stronghold

• Invasive predator control --  reducing nest predation and adult mortality

• Carefully managed population supplementation -- under specific conditions, this offers the most consistent benefit

How We Monitor

The Grenada Dove monitoring program will use complementary approaches to track this elusive species:​

1. Territory Mapping: The long-term trend engine. Trained observers map singing males repeatedly across the breeding season, building spatial understanding of territories while minimizing double-counting. Given genetic evidence of potential male bias, population estimates use conservative multipliers with clearly stated assumptions.

2. Acoustic Monitoring: The coverage extender. Passive acoustic recorders (AudioMoths and similar devices) add temporal depth—capturing dawn choruses, nighttime activity, and periods when human observers aren't in the field. Audio archives also allow quality assurance and future reanalysis as methods improve.

3. Distance Sampling: For abundance estimation with confidence intervals. Observers record exact distances to detected birds, allowing statistical correction for detectability. This approach works best in more open habitat and provides calibration for territory mapping.

4. Habitat Assessment: Fixed-radius vegetation plots quantify canopy cover, tree species composition, and forest structure at dove locations versus available habitat. This reveals what makes "good" dove habitat and helps predict where restoration or protection efforts will be most effective.

5. Breeding Monitoring: Exceptionally challenging for this species—nests are difficult to find and easily abandoned. Remote trail cameras and strict non-invasive protocols help document nesting attempts and identify predators without disturbing birds.

6. Future Work -- Individual Tracking: Mist-netting and banding follow standardized protocols for critically endangered species: minimal handling times, priority processing, and genetic sampling (feather or blood) to inform demographic models and assess connectivity between populations.

All methods prioritize data quality and comparability over time -- the only way to detect real trends in a population this small.