Asynchrony and Provisioning: Three Days Inside the Finch Nest

Three days bracket a transition I have been waiting weeks to see resolve. On May 11 the cup still held both naked chicks and unhatched eggs; by the evening of May 13, the family had settled into the steady, mechanical cadence of a brooding-and-feeding operation with as many as five gaping mouths.

The hatching window did not close cleanly. Late on the eleventh, at 16:11, an interval frame caught three pale, speckled eggs lying among the chicks; forty minutes later only two remained visible. The next morning at 10:51 the count was again three eggs alongside two chicks — a reminder that asynchrony in House Finches can stretch hatching across several days, and that the female’s brooding posture obscures more than it reveals. By the thirteenth, only late-night IR clips at 21:27 and 23:01 hinted at one or two ovoid shapes still tucked at the cup’s rim; their NIR-albedo was bright enough to read as unhatched rather than as a pale chick flank, but I am holding that identification loosely.

The provisioning rhythm tightened across the three days. On the eleventh, male feeding visits were spaced through the afternoon at roughly hourly intervals — 12:38, 13:22, 14:12, 15:16, 16:07, 17:17, 18:18, 19:43 — with two coordinated arrivals where both adults perched at the cup together (07:51 and 09:50). The twelfth showed the same pattern but compressed: visits at 06:27, 07:04, 07:33, 08:07, 08:34, 09:29, 10:34, 11:05, 11:57, 13:04, 14:02, 14:52, 15:56, 17:17, 18:41, 19:27. By the thirteenth I had stopped counting individual arrivals and started counting gaps; the male’s interval between visits had shortened to thirty to ninety minutes through the working hours of the day.

Chick development tracked the increase in deliveries. On the eleventh, the descriptions still read “pinkish, naked” through the morning, drifting to “dark” and “fuzzy” by evening — a shift consistent with pin feathers breaking the skin. The twelfth opened with chicks described as small grey-downy shapes with yellow-orange beaks; the contrast between the bright gape and the duller body had grown striking enough to be picked up reliably even in shaded color frames. By the thirteenth, gapes were visible from across the cup, and the male’s afternoon visit at 11:58 produced the first single-frame count of five chicks — the full clutch resolved at last, four days after the first hatch I logged on May 7.

The female’s behaviour shifted in parallel. On the eleventh she brooded for long stretches with only minute-scale departures, and both adults converged at the cup more than once. By midday on the twelfth her absences had lengthened; an interval frame at 05:41 showed the cup unattended with naked chicks fully exposed, and similar gaps recurred through the morning. On the thirteenth, the unattended stretches were the rule rather than the exception during daylight, with the chicks huddled in a loose pile between visits. She still settled in each evening — confirmed continuously from around 20:07 on the eleventh, 20:29 on the twelfth, and 20:00 on the thirteenth — and the IR clips through each night showed her pressed low with pale chick shapes ringing her flanks.

A few smaller observations are worth keeping. A human head briefly entered the sunroom frames around 11:52 on the eleventh, accounting for a recording gap rather than any disturbance to the nest. Conflicting clips on the twelfth — one camera reading “empty,” another reading “chicks alone” within the same minute — are almost certainly an artefact of staggered motion triggers and slightly different framings rather than rapid adult turnover. And the apparent egg sighting at 07:01 on the twelfth, with chicks already well-documented either side of it, illustrates how easily a partially shadowed chick belly can read as a shell when the NIR-albedo is misjudged.

Three days, then, from a clutch in mid-hatch to a brood in active feather. The cadence of the male’s visits is the surest sign that things are going well; the female’s lengthening absences, the second.