Tag Archives: eggs

Day 1: A New Beginning!

Gray Catbird incubation lasts about 12 days. During that time, this mom was brave and vigilant. As this was right outside our front door (and we don’t have the luxury of alternative exits) I knew she’d be dealing with our comings and goings throughout this whole breeding ordeal. Since the shrub had been recently trimmed, I was lucky that at one point while walking past you could see straight through a gap to see her quietly watching you.

Embryos require a fairly stable and narrow temperature range, so her vigilance is important. Carryover effects of suboptimal temperatures during incubation range from slower nestling growth (Ospina et al. 2018, Ecol Evol) to more fearful behaviors in the offspring (Bertin et al. 2018, Scientific Reports). In catbirds, the female does all the incubating and will typically sneak off to eat around sunrise. I never directly saw the male coming to feed the female on the nest during the day, but that behavior is also typical for these songbirds.

On July 20, we had our first nestling! (It was only 8 days after I first noticed the eggs, so the first must have been laid a few days earlier as it usually takes about 12 days to hatch.) It doesn’t immediately start begging for food, so if you listen in the video you can hear the adult give several “quirt” calls that eventually trigger the open-mouthed begging response.

Baby birds have very little strength at first, so it takes a lot of effort to receive food!

Gray Catbird nest!

In early July I noticed a Gray Catbird eyeing an existing nest right outside my front door. This was unexpected because the nest was left over from last year, and it was only uncovered with some shrub-trimming last fall. Interestingly, the Cornell Lab of Ornithology Birds of the World species account for the Gray Catbird mentions that a “new nest is usually built for each brood and for renests, but there is one observation of reuse of a Gray Catbird nest between years (Marshall et al. 2001).”

Catbird eggs are typically a nice shade of blue.

Because of this, I thought maybe she was just checking out the existing nest, especially since it was relatively late in the season and it would likely be a renest or second brood. But by July 12 she was incubating two beautiful blue eggs! I wasn’t sure how many eggs she’d lay, since clutch sizes vary from 1 – 6 eggs, but I wanted to keep an eye on her without disturbing the nest. I mounted a GoPro camera above the nest to remotely take videos and monitored her progress, but she stuck with just the two eggs. Stay tuned to see what happened!

A GoPro camera mounted above the nest will let me monitor their progress without disturbing the birds!