April 16, 2025: Egg Development (Week 2)

– Rapid Embryonic Growth: The embryos begin developing visibly defined features such as limb buds, eyes, and a beating heart. By the end of this week, they start to resemble tiny birds.
– Increased Metabolic Activity: Nutrient absorption from the yolk intensifies, and the demand for oxygen grows as organs continue to form.
– Membrane Development: The inner shell membrane thickens, and the chorioallantoic membrane—critical for respiration and waste removal—expands across the inner shell.
– Egg Turning: Regular turning of the eggs by the adults helps prevent the embryo from sticking to the shell membrane and ensures even warmth and proper development.

Adult Peregrine Behavior Patterns (Week 2 of Incubation)

Division of Labor
– Incubation Roles:
– The female remains the primary incubator, staying on the nest the majority of the time.
– The male does brief incubating stints, often 5–20 minutes, while the female feeds or preens.

– Shifts and Communication:
– Nest exchanges are polite and purposeful, often involving soft chirps or trills between mates.
– The female may stretch or circle briefly before resettling on the eggs after a break.

Foraging and Food Delivery
– The male continues to supply most of the food:
– He may hunt multiple times a day depending on weather and prey availability (typical prey includes pigeons, starlings, flickers, and shorebirds).
– Food is sometimes partially plucked before being brought to the nest ledge or a nearby feeding perch.

Territory Defense
– Both adults maintain a strong presence near the nest site:
– The **male** often perches nearby to guard the nest and watch for threats.
– They may engage in noisy aerial displays or stoops if another raptor approaches.

Incubation Behavior
– Egg Turning: Both adults turn the eggs several times per hour using their beaks and talons—an instinctive behavior to promote healthy development.
– Temperature Regulation: The adult on the nest adjusts its posture in response to wind, rain, or direct sun, creating an ideal microclimate for the eggs.