Mourning doves are a common bird species found throughout North America. They are known for their soft, mournful cooing call which gives them their name. Mourning doves build flimsy nests out of twigs, grass, and sometimes pine needles, typically on the ground or in low bushes. The female lays two white eggs in each clutch and both parents take turns incubating them. But just how long do mourning doves actually sit on their eggs before they hatch? Let’s take a closer look.
Incubation Period
The incubation period for mourning dove eggs – the time from when the eggs are laid to when they hatch – is approximately 2 weeks. More specifically, it takes about 14-15 days for mourning dove eggs to hatch.
The incubation duties are shared by both the male and female parent doves. They take turns sitting on the nest and eggs, with each parent taking shifts of between 20 minutes to over an hour at a time. During the switch off, the off-duty parent will leave the nest to feed and drink. This constant incubation by both parents helps maintain the proper egg temperature and humidity levels needed for embryo development.
Hatching
Towards the end of the 14-15 day incubation period, the baby doves inside the eggs will begin cheeping and pipping – using their egg tooth to break through the shell. It takes 12-48 hours from the first pips for the baby birds to fully hatch out of their eggs.
Hatching can be an exhaustive process for the young doves as they push, twist, and nibble their way out. Their parents continue to diligently incubate and turn the eggs to help the hatchlings emerge. At the same time, the parent doves also poke holes in the pip marks to help the babies breathe easier until they are ready to come out fully.
Once all the baby doves in a nest have hatched, the parents will remove the broken eggshells and proceed to brood and care for their new offspring. The hatchlings are altricial, meaning they are helpless, featherless, and require extensive parental care for sustenance and warmth.
Why 14-15 Days?
So why does it take approximately 2 weeks for mourning dove eggs to hatch? There are several key reasons:
Embryo Development Rate
The duration of mourning dove egg incubation is tied to the rate of embryo development. The mourning dove embryo must grow from a single fertilized cell into a fully formed hatchling with all organs and body parts. It takes 14-15 days for the dove embryo to undergo enough cell divisions and organogenesis to be ready for hatching. Their development rate is slower than many other bird species like chickens or ducks.
Small Eggs
Mourning dove eggs are relatively small, averaging about 30 grams. With less egg mass and nutrients, the dove embryos take longer to fully develop compared to embryos of larger bird species. The small eggs do allow mourning doves to lay multiple clutches per breeding season.
Low Incubation Temperature
The average incubation temperature maintained by mourning dove parents is around 37.5°C. This is lower than the incubation temperature of chickens (37.8°C) and results in a slower overall growth rate. Without the higher external heat, mourning dove embryos require more time to fully form and mature.
Species Characteristics
Incubation periods are inherent characteristics adapted for each unique species. The 14-15 day incubation cycle of mourning doves reflects their physiology and allows time for proper growth. It ensures healthy, well-developed hatchlings suited to survive in their habitats.
Incubation Behavior
To keep the eggs at optimum temperature and humidity for 14-15 days straight, mourning doves need to demonstrate persistent nesting and incubation behaviors:
Flushed Body Feathers
The parent dove plumps up its body feathers while sitting on the eggs, allowing more body heat transfer. The feathers lie smooth and slightly separated.
Incubation Patches
Bare patches of skin develop on the dove’s lower belly from the constant contact with the eggs. More blood vessels are redirected towards the skin surface there to help transfer more warmth.
Egg Turning
The parent doves frequently shift position on the nest and gently turn the eggs using their beaks. This prevents the embryos from sticking and distributes heat evenly.
Constant Changeovers
The parent doves change over incubation duties every 20 minutes to over an hour. This gives each parent sufficient breaks to eat and drink while still maintaining continuous egg warmth.
Alertness
The incubating dove is very alert and watchful on the nest. At any signs of threats, they immediately return to brooding the eggs for protection.
Incubation Stage | Duration |
---|---|
Laying | 2 eggs per clutch, 1 day apart |
Incubation | 14-15 days |
Hatching | 12-48 hours from initial pipping |
Factors that Impact Incubation
While the normal incubation period for mourning doves is 14-15 days, there are circumstances that can lengthen or shorten the duration:
Temperature
Extreme cold or hot weather can impact incubation. Temperatures dropping well below 10°C may delay hatching while a heat wave can speed it up slightly. However, mourning doves incubate very persistently through temperature fluctuations.
Age of Parents
Younger, inexperienced parent doves may have lower incubation attentiveness and cause delayed hatching. Older parents tend to have better breeding habits.
Predation
Disturbance of the nest by predators can shorten incubation if the parents are forced to permanently abandon the eggs. However, mourning doves are dedicated to their nests despite threats.
Human Interference
Human activities like habitat loss and nest disturbances can impact mourning dove nesting success and incubation duration. Conservation of their nesting areas is important.
Egg Fertility
Unfertilized eggs or embryos that died very early during incubation will fail to hatch after 14-15 days. But the mourning dove parents often continue brooding the eggs diligently for some time.
Egg Rolls Out of Nest
The flimsy mourning dove nests may not hold the eggs securely. Any that roll out are abandoned and left unincubated, causing failed hatching.
Conclusion
In summary, mourning doves typically incubate their eggs for 14-15 days before they hatch. Both parent doves share the persistent incubation duties, with the male and female switching on and off the nest regularly. Throughout the 2-week period, the diligent parents maintain the proper egg temperature and humidity levels to allow for complete embryo growth and development. Barring any disruptions or temperature extremes, the baby doves hatch fully-formed and ready to be cared for by their attentive parents. The 14-15 day incubation period seems adapted specifically for mourning doves to ensure healthy hatches. Their small size, egg characteristics, and development rates all contribute to this species-specific incubation duration. With dedicated care by the parents, mourning dove nests will go from eggs to hatchlings right on schedule.