The Eurasian collared-dove (Streptopelia decaocto) is considered an invasive species in many parts of the world outside its native range. This medium-sized dove originally comes from Asia and Europe, but has colonized new areas rapidly in recent decades. There are several reasons why the Eurasian collared-dove is so successful at establishing itself in new regions:
Rapid reproduction rate
Eurasian collared-doves can reproduce quickly and often. The females can lay clutches of 1-3 eggs up to 6 times per year. They reach sexual maturity early, at around 5-6 months old. This high reproductive rate allows their populations to grow rapidly once introduced to a new area.
Generalist feeders
These doves are opportunistic and flexible when it comes to food sources. Their diet consists mainly of seeds and grains, but they will also eat fruit, nuts, and some insects. By not relying on one specific food type, collared-doves are able to adapt and take advantage of many habitat types for foraging.
Ability to live near humans
Eurasian collared-doves thrive in human-altered environments like farmland, rural areas, suburbs, and urban parks. They nest on artificial structures and scavenge for food around seed sources provided intentionally or unintentionally by people. Their tolerance for human proximity gives them an advantage over native species that tend to avoid human disturbance.
Lack of natural predators
In their expanded non-native range, Eurasian collared-doves often escape pressures from predators, parasites, and diseases that would normally keep their populations in check. With fewer threats, their populations can grow unhindered in environments where they face less competition from other species.
Climate matching
The Eurasian collared-dove is well-adapted to a variety of temperate climates. Regions with similar climate conditions to the dove’s native range provide suitable habitat for establishment. Their wide temperature tolerance also allows them to thrive across diverse geographic areas.
Rapid dispersal abilities
These agile doves are strong flyers capable of dispersing long distances quickly. Their average dispersal rate is around 30 miles per year. But they have been documented dispersing over 620 miles in just a few months. This mobility allows them to colonize new areas rapidly as they expand their range.
Behavioral flexibility
Eurasian collared-doves exhibit flexible behaviors that aid their adaptation to new environments. For example, they are able to modify their foraging behaviors and habitat use in human-altered areas compared to more natural settings. They also readily nest on man-made structures, showing behavioral plasticity.
Impacts of invasion
The introduction and spread of the Eurasian collared-dove can cause negative impacts on ecosystems and native species in several ways:
Competition for resources
Collared-doves can compete with native birds for food sources, nesting sites, and other resources. Their aggressive foraging behavior often displaces other birds.
Pathogen transmission
These doves may facilitate the spread of diseases like parasites, viruses, and bacteria into new regions where native species lack immunity.
Crop damage
Large flocks can cause significant damage to agricultural crops and stored grains in some areas. Their high numbers exacerbate these effects.
Genetic dilution
Collared-doves may hybridize with closely related native dove species, leading to genetic mixing and loss of uniqueness.
Ecosystem instability
As an abundant invasive species without natural population controls, Eurasian collared-doves can potentially disrupt ecosystem balance, nutrient cycling, and other functions.
Control and management
Once established in new areas, Eurasian collared-doves can be very difficult to control or eradicate. Potential management approaches include:
- Population reduction through trapping or culling
- Discouraging foraging and nesting through habitat modification
- Exclusion methods and deterrents to protect valuable resources
- Prevention of further colonization by managing dispersal pathways
- Community education and enforcement of laws prohibiting feeding
However, these doves are highly adaptable and resilient to control efforts. Complete eradication is unlikely once populations are established. Therefore, prevention of invasion through early detection and rapid response is critical.
Conclusion
In summary, the Eurasian collared-dove’s rapid reproduction, flexible behavior, tolerance of humans, climate matching abilities, generalist feeding, lack of predators, and rapid dispersal all enable it to successfully invade and establish in new areas outside its native range. This leads to detrimental impacts on native ecosystems including competition, pathogen transmission, crop damage, and genetic dilution. Preventing introductions and managing spread are crucial to reducing collared-dove invasion and protecting native species.