This video from Britain is called An Introduction to the Barn Owl.
17 MARCH 2015
Secondary sexual characters often signal qualities such as physiological processes associated with resistance to various sources of stress. When the expression of an ornament is not sex-limited, we can identify the costs and benefits of displaying a trait that is typical of its own sex or of the other sex.
Indeed, the magnitude and sign of the covariation between physiology and the extent to which an ornament is expressed could differ between males and females if, for instance, the regulation of physiological processes is sensitive to sex hormones.
Using data collected over 14 years in the nocturnal barn owl Tyto alba, we investigated how nestling body mass covaries with a heritable melanin-based sex-trait, females displaying on average larger black feather spots than males. Independently of nestling sex, year and time of the day large-spotted nestlings were heavier than small-spotted nestlings.
In contrast, the magnitude and sign of the covariation between nestling body mass and the size of parental spots varied along the day in a way that depended on the year and parental gender. In poor years, offspring of smaller-spotted mothers were heavier throughout the resting period; in the morning, offspring sired by larger-spotted fathers were heavier than offspring of smaller-spotted fathers, while in the evening the opposite pattern was found.
Thus, maternal and paternal coloration is differentially associated with behaviour or physiology, processes that are sensitive to time of the day and environmental factors. Interestingly, the covariation between offspring body mass and paternal coloration is more sensitive to these environmental factors than the covariation with maternal coloration. This indicates that the benefit of pairing with differently spotted males may depend on environmental conditions, which could help maintain genetic variation in the face of intense directional (sexual) selection.
After the ringing of the waxwings, we were still in Oulu, northern Finland, on 11 March 2015. We went to the harbour: much ice, but not totally frozen. Then, in the distance, we saw an otter between the ice floes.
A Finnish naturalist said this was the first otter he had seen since two years ago.
Every now and then, the otter dived, and then re-appeared.
Gradually, it came closer.
Just before dusk, at 17:30 we had gone to a road with coniferous and birch trees on both sides.
Then, we saw this Eurasian pygmy owl. It flew from tree to tree, preferring tops.
Stay tuned, as 11 March was our first full day, not our last day, in Finland!
This video from the USA says about itself:
27 May 2009
Hawk Creek Wildlife Center’s breeding project. Time elapsed barn owl egg hatching.
From the Cornell Lab of Ornithology in the USA:
The Barn Owls that took up residence in a new nest box on a Texas ranch are showing promising signs for the upcoming breeding season. The male has been bringing prey animals to the nest in displays of courtship, and both birds have been cozily tucked in their nest box almost every day for the last few weeks.
We’ve seen them mate a few times, and we hope to see them lay their first eggs sometime before the middle of April. Watch cam.
This video is about a long-eared owl resting.
Brenda Boeve made this video in her garden in the Netherlands.