Brown thrasher molting in the USA

This video from the USA says about itself:

Brown Thrasher Molting – Bald Headed Songbird Season

26 August 2016

Late summer is bald bird or molting season. First time I’ve seen the normally aloof and well-groomed Thrasher in such a state. It will only last a few weeks.

A feather is a “dead” structure, analogous to hair or nails in humans and made of the same basic ingredient, the protein keratin. This means that when they get damaged, feathers can’t heal themselves—they have to be completely replaced. This replacement of all or some of the feathers is called molt. In addition to providing a new set of healthy feathers, molts often provide a new look to the bird’s plumage—new colors or patterns that can indicate the bird’s age, sex, or the season of the year.

Molt is extremely variable. Observed patterns can vary by species, by individual, from year to year, and by individual feathers on the same bird. Molts can be either complete, in which the bird replaces every one of its feathers over the same molt period; or partial, in which the bird replaces only some of its feathers (for example, flight feathers or body feathers).

Molt keeps birds in top flying condition by replacing feathers that have become worn or damaged with completely new feathers. However, if a bird loses an entire feather, that feather will begin growing back immediately rather than waiting for the next molt. (This is why people clip the flight feathers of captive birds rather than plucking them out).

Molting occurs in response to a mixture of hormonal changes brought about by seasonal changes. The entire process is complex and many questions remain regarding how the process is controlled. A basic understanding of molting patterns can be a useful aid in identifying many species and in determining their age.

Blue cohosh plants in the USA

This video from the USA says about itself:

25 August 2016

Blue Cohosh is a beautiful plant when the berries turn ripe in late summer. This was a large patch in the Great Smoky Mountains that covered a hillside. Noted for its medicinal properties its roots are used to make various mixtures. “Cohosh” is from the Algonquin Indian word meaning “rough,” and it refers to the appearance of the roots. The root is used to make medicine.

Northern cardinal fledgling video

This video from the USA says about itself:

28 August 2016

Newly fledged Northern Cardinal is still being fed by the parents while learning what food is good to eat by trial and error. This is the second brood for these Cardinals – by leaving the nest in late August the young will have plenty of time to be ready for winter. Blue Jays, Woodpeckers and Cardinals all have had two broods this year.