The Curious Case of Iris and the Three Eggs

On 19 May, Iris left her nest at 12:24:59. It started raining during the afternoon. She did not return until the late evening when she arrived at her nest with a fish in her right talons and a full crop at 19:52:47. She had been away for close to seven and a half hours. I want to call this the curious case of Iris and the three eggs.

For thirty-nine minutes, Iris looked down at the eggs several times while also looking around her close environment. Several times it appeared that she was leaning down and talking to the eggs. She never rolled the eggs once. She flew off the nest with her fish at 20:31:37.

Iris arrives at her nest with the fish skin.

She immediately begins looking down and chattering at the eggs after she horks the last of her meal. She does not ever attempt to incubate the eggs.

Besides looking down at her eggs, Iris will continually check her environment.

Iris would look up and then down, look around and then down again. Each time she might lower her head closer to the eggs appearing to talk to them each time.

Iris looked and leaned down to the eggs many times during that short visit.

Iris is getting ready to leave, backing up carefully not to break the eggs she gets a little unsteady and raises her wing to balance herself.

Iris had started to take off but she stopped. She looked down at her eggs again before flying out. There was something very ‘sad’ about Iris continually looking at the eggs the way she did last evening.

Iris flies off the nest with the fish. She appears to be headed to the pole.

As the lights come on, we hope that Iris is at her roost keeping as dry and warm as she can. She will certainly be full of fish!

The rain is really pitching down during the night.

Iris arrives back at the nest at 6:15 am with what is left of her morning meal at the nest. It has been raining steadily during the night.

Iris wastes no time getting on the nest and incubating the eggs after she horks the fish skin.

Iris rolls the eggs and aerates the nest.

Iris does some nest maintenance – moving some sticks and working on the wall.

Iris rolls the eggs and aerates the nest again. She will do this several times.

At 7:30:02, Iris gets off the eggs and goes to the perch leaving the eggs exposed to the rain. Iris was at her nest incubating the eggs for an hour and fifteen minutes.

Iris looks like she is shivering but she is flapping those feathers to try and get the rain off!

The rain is wet and cold in Missoula, Montana. Iris has her feathers floofed. It is 4 degrees C (or 39 degrees F) and will rise to 6 degrees with continual drizzle or rain. One forecast is for snow.

Rather than commenting as I went along, I thought I would just simply post a summary of Iris’s behaviours during late last evening and early this morning. We are all familiar with the fact that the females can hear the chicks when they are almost ready to hatch and they talk to them, encouraging the little ones to get out of the shells. Many females (and males) talk to the eggs during the entire incubation period.

As a human I can only record what Iris does making assumptions based on past experiences. Iris is, however, an anomaly. She is the oldest female Osprey in the world – at either 25 or 28 years old. There are some close to her like Mrs G at Glaslyn who is either 20 or 21 and still fledging chicks. Mrs G has a fantastic mate in Aran. So there is no comparison. Iris has not really had a devoted mate since Stanley. Iris’s last fledgling was 2018 – only one survived. Louis was not a good provider. One died. That was three years ago. Louis has been completely absent from Iris’s life except to show up to mate or steal a fish since 2019. Ravens have stolen the eggs in past years. We do not know if these eggs of Iris would be viable because she does not have a mate to help her.

I was surprised Iris was back incubating them for a bit in the morning. Tiger Mozone told me that he has seen eggs last in the cold for an extended period provided they had not been incubated and it had not been too cold. Is 39 F too cold? Oh, I would love to get into this female Osprey’s head!

Thanks for joining me. I will be nest hopping later today. Hatches and fish fights!

Thank you to Cornell Bird Lab and the Montana Osprey Project for their streaming cam where I grabbed my screen shots and to Tiger Mozone for the great conversation.

Leave a Reply