The Ilhas Cagarras (Cagarras Islands) are an uninhabited archipelago located off Ipanema, a major beach of the southern coast of the city of Rio de Janeiro, Brazil. They have been designated a federal natural monument since 2010. Location The archipelago is in the municipality of Rio de Janeiro, in the state of Rio de Janeiro. It has an area of . It is an important area for fisheries and tourism, and is subjected to upwelling of cold waters during summer. The water quality is relatively poor due to its close proximity with Rio's city waste water disposal. The islands are nonetheless frequented by day excursions of eco-tourists. The archipelago consists of the following islands ("ilha" in Portuguese means island, "ilhota" = islet): Ilha Cagarra Ilha de Palmas Ilha Comprida Ilha Filhote Ilhota Grande Laje de Cagarra The first three are the largest. Ilha Cagarra, the island group's namesake, is the tallest (79m/259 ft.) and most visible from land. Although the islands Ilha Redonda and Ilha Redondinha are located nearby, they are not part of the Cagarras archipelago. Origin of the name There is no consensus among authors about the origin of the name of this archipelago. The most commonly accepted version says that the toponymy would be due to the large amount of excrement (in Portuguese, "cagádas" ) of seabirds that live, nest and feed on these islands. After feeding mainly on fish, these birds excrete their feces, rich in calcium, on the rocky slopes of the islands, staining them white. This hue is clearly visible from the shore of Ipanema, one of the south beaches of Rio de Janeiro In 1730, its main island, appears on a nautical chart with a Frenchified name "Island Cagade." In another letter, dated 1767, the same appears with the island carrying its name in Portuguese: "Crappy Island." "Ilha Cagáda" Another possibility for its name, is that Portuguese sailors wrongly identified the frigatebirds (fragatas in Portuguese) that nest on these islands, with the Scopoli's shearwater (cagarras in Portuguese) seabirds that live in the archipelagos of Madeira and the Azores (Portuguese territories): the shearwater or cagarra (Calonectris diomedea) is not found on Brazilian islands. History of the Archipelago The islands are situated in proximity to the discharge in the sea of sewage from almost all the South Zone of Rio de Janeiro, through the Ipanema canal, an important work of sanitary engineering built in the