The burrowing owl is a small, long-legged owl found throughout open landscapes of North and South America. These owls get their name from their habit of nesting underground in burrows dug out by mammals like prairie dogs, ground squirrels, and badgers. Burrowing owls are somewhat unique among owls in that they are often active during the day, especially in the breeding season.
Baby burrowing owls, called owlets, stay in the nest burrow for quite a long time compared to other owl species. Owlets are cared for by both parents and depend on them for food and protection while growing. The exact length of time burrowing owl babies remain in the nest can vary based on several factors.
Typical Nesting Timeline
The burrowing owl nesting season usually runs from March through August. Here is a general timeline for burrowing owl nesting and development:
– Egg laying: In March or April, the female burrowing owl lays a clutch of 6-12 white eggs over several days. She incubates them for 3-4 weeks.
– Hatching: The eggs hatch over a period of a few days in April or May. The owlets are covered in white down when they emerge.
– Early care: For the first 2 weeks, the owlets remain in the nest burrow full time, being fed and cared for by the parents. They grow additional down feathers during this time.
– Leaving the burrow: At around 2-3 weeks old, the owlets start emerging from the burrow entrance in the evening. The parents continue to feed and watch over them.
– Fledging: At 4-6 weeks old, the owlets fledge and leave the nest burrow. However, they cannot yet fly well at this stage.
– Gaining independence: Over the next several weeks, the fledglings improve their flying skills and start hunting on their own. But they continue to be fed and accompanied by the parents.
– Dispersal: At 8-10 weeks old, the young owls finally disperse from their parents’ territory and strike out on their own.
So in total, burrowing owl chicks remain centered around the nest for about 2 months as they grow and develop flying capabilities. Even after fledging, they are not fully independent for another 1-2 months.
Factors Affecting Nest Time
The exact amount of time baby burrowing owls spend in the nest can vary based on several factors:
– Number of owlets: Broods with more owlets may fledge earlier, as competition for food is higher. Single owlet broods may be slower to develop.
– Food availability: In years or regions with abundant food, owlets may grow faster and fledge sooner. Leaner conditions could delay them.
– Weather: Cold temperatures or heavy rain could keep owlets in the burrow longer for protection. Mild weather allows them to venture out earlier.
– Health/genetics: Weaker or smaller owlets in a brood may need more time before fledging compared to stronger siblings.
– Nest site: A remote, protected burrow may allow for longer nest time. More exposed or dangerous areas may hurry fledging.
– Predators: Higher pressure from predators could force earlier fledging. Low predation allows for longer nesting.
– Human disturbance: Noise, activity, and encroachment near nests can sometimes shorten nesting time. Undisturbed sites allow for longer stays.
– Geographic location: Burrowing owl subspecies or populations in harsher climates may have slightly different fledging patterns.
So while the typical nesting time is around 2 months, a range of 6-10 weeks is normal depending on various influences on that specific nesting site and season.
Importance of Extended Nest Time
The burrowing owl’s long nesting period compared to other owl species has to do with their habitat and lifestyle. Living underground in tunnels, the owlets are well-protected and have a secure place to grow. Their tunnel homes also mean the parents must actively deliver food to the burrow.
Spending more time in the nest allows the owlets to:
– Develop thermoregulation: The underground burrow provides insulation as they transition from down to juvenile plumage.
– Build flight muscles: Half-grown wings aren’t ready for flying or hunting at hatching. Longer time in the nest allows muscles to develop.
– Grow a full juvenile coat: Their adult-like plumage pattern doesn’t come in until just before fledging.
– Learn hunting skills: Parents demonstrate and train owlets in hunting before full independence.
– Avoid predation: The nest site keeps vulnerable chicks safely hidden from predators.
– Bond with parents: Longer care time ensures strong bonds between owlets and parents.
Overall, the extended nesting period seems to give burrowing owl chicks the best chance at surviving to adulthood. The extra time in a protected burrow with attentive parents allows them to hone the skills needed for independence.
Behavioral Milestones
As they spend 2 months in the nest, burrowing owl chicks progress through important growth stages:
Week 1:
– Hatch from eggs blind and mostly featherless.
– Make peeping calls and lift heads when begging for food.
– Sleep and stay in burrow full time.
Week 2:
– Open eyes around 5-8 days old.
– Grow white downy feathers on head and body.
– Move around in nest and interact with siblings.
– Parents provide food day and night.
Week 3:
– Become more active in burrow during day.
– Begin preening down feathers.
– Start hissing and snapping defensively when disturbed.
– May appears at burrow entrance briefly.
Weeks 4-5:
– Body feathers start transitioning from down to juvenal plumage.
– Increased time upright and moving around burrow entrance.
– Better coordination and wing exercising.
– Occasional short flights hopping around outside burrow.
Weeks 6-7:
– Nearly adult-like plumage attained by week 6.
– Frequent peering and perching at burrow entrance.
– Short practice flights improving control and distance.
– Venture short distances from burrow with parents.
Weeks 8-10:
– Capable of sustained flight to forage and escape danger.
– Completely independent in finding food by week 10.
– Disperse from parents’ territory by end of week 10.
Tracking these benchmarks can help observe whether owlets are developing on a healthy schedule during their 8-10 weeks in the nest area.
Comparisons With Other Owls
The burrowing owl has a much longer nestling phase than most other owl species. Here’s how it compares:
Barn Owl
| Fledge at 4 weeks |
| Dependent on parents 2-3 more weeks |
| Hunt on own by 8 weeks |
Eastern Screech Owl
| Fledge at 6 weeks |
| Parents feed 3-4 more weeks |
| Disperse around 12 weeks |
Great Horned Owl
| Fledge at 5-6 weeks |
| Independent hunters by 12 weeks |
The burrowing owl’s long nest time seems suited to their habitat, ensuring the chicks are well-prepared to leave the burrow and face competition and predators above ground. Other cavity and ground nesters like barn owls have a moderately extended period, while canopy owls like screech and horned owls fledge more quickly.
Conclusion
Baby burrowing owls remain in the nest burrow for an extended period of around 2 months as they grow and develop the skills needed for independence in their open, underground environment. Typical burrowing owl owlets hatch in spring, emerge from the burrow at 2-3 weeks, fledge at 4-6 weeks, become adept fliers by 8 weeks, and finally disperse from parental care at 8-10 weeks of age. This long juvenile phase in a protected burrow provides time to transition to adult plumage, build flight muscles and stamina, learn hunting from parents, and avoid early predation. The nesting duration of burrowing owls is longer than other owl species, befitting their habitat and helping ensure offspring survive into adulthood. Tracking growth milestones and watching for when owlets emerge, fledge, and depart the natal burrow can provide insight into the health and development of burrowing owl chicks.
