Rynchops

The skimmers, forming the genus Rynchops, are tern-like birds in the family Laridae. The genus comprises three species found in South Asia, Africa, and the Americas. They were formerly known as the scissorbills.<ref>Template:Cite OED.</ref>

Description

The three species are the only birds with distinctive uneven bills, where the lower mandible is longer than the upper.Template:Cn This remarkable adaptation allows them to fish in a unique way, flying low and fast over streams.<ref>Template:Cite journal</ref> Their lower mandible skims or slices over the water's surface, ready to snap shut any small fish unable to dart clear. The skimmers are sometimes included within the gull family Laridae but separated in other treatments which consider them as a sister group of the terns.<ref>Template:Cite journal</ref> The black skimmer has an additional adaptation and is the only species of bird known to have slit-shaped pupils.<ref>Template:Cite journal</ref> the forehead, ends of the secondaries, tail feathers and under parts are white, the rest of the plumage is black and the basal half of the bill is crimson.<ref>Template:Cite book</ref> Their bills fall within their field of binocular vision, which enables them to carefully position their bill and capture prey.<ref>Template:Cite journal</ref> They are agile in flight and gather in large flocks along rivers and coastal sand banks.<ref>Template:Cite magazine</ref>

They are tropical and subtropical species which lay 3–6 eggs on sandy beaches. The female incubates the eggs. Because of the species' restricted nesting habitat the three species are vulnerable to disturbance at their nesting sites. One species, the Indian skimmer, is considered endangered by the IUCN due to this as well as destruction and degradation of the lakes and rivers it uses for feeding.<ref>Template:Cite iucn</ref>

Taxonomy

The genus Rynchops was introduced in 1758 by the Swedish naturalist Carl Linnaeus in the tenth edition of his Systema Naturae.<ref>Template:Cite book</ref>Template:Efn The genus name Rynchops is from the Ancient Greek ῥυνχος/rhunkhos meaning "bill" and κοπτω/koptō meaning "to cut off".<ref>Template:Cite book</ref> The type species is the black skimmer (Rynchops niger).<ref>Template:Cite book</ref>

As in later editions of the works of Linnaeus, the correct spelling (from the Greek words {{#invoke:Lang|lang}} and {{#invoke:Lang|lang}}, together meaning "beak-face") should be rhynchops and this is often adopted. However, the misspelling rynchops was the one first published by Linnaeus and continues to be more commonly used.<ref>Template:Cite journal</ref> Similarly, the gender of the Greek and Roman words is feminine and the genus was originally treated as such (R. nigra) but Rynchops is now usually treated as a masculine noun (R. niger).

Species

The genus contains three species.<ref>{{#invoke:citation/CS1|citation |CitationClass=web }}</ref> Template:Species table

External links

• Skimmer videos on the Internet Bird Collection