The eclipse plumage is a term used to describe the non-breeding plumage of a few groups of species. It is only used to describe the non-breeding plumage of males when their breeding plumage is iridescent or glossy. The iridescent breeding plumage is replaced by a drab non-breeding plumage.
In southern Africa, the only group of species for which the term “eclipse plumage” can really be used are the sunbirds. Male Malachite Sunbirds, for example, have an eclipse plumage during the non-breeding season. The males of several southern African sunbirds do not have an iridescent breeding plumage (e.g. Olive Sunbird) and therefore no eclipse plumage. Male Orange-breasted Sunbirds stay in their iridescent breeding plumage all year, and so they also do not have an eclipse plumage!
Many wader species, for example Ruddy Turnstones, have a bright and colourful breeding plumage and a relatively dull non-breeding plumage, but no one describes the non-breeding plumage of a wader as “eclipse plumage”, because the breeding plumage is not glossy. For waders we talk about a non-breeding plumage. And the same applies to the bishops and whydahs, with brightly coloured breeding plumages and dull non-breeding plumages. We don’t talk about the eclipse plumage of a Southern Red Bishop, we talk about its non-breeding plumage.
Some species of swallows have a glossy blue plumage when breeding, and lose the gloss outside the breeding season. The gloss wears off. They don’t replace the feathers.
And the “glossy starlings” are glossy throughout the year.
In Europe and North America there are ducks which have a glossy breeding plumage, which is replaced by a dull plumage. So, like the sunbirds, these species can be described as having an “eclipse plumage”!