Floating reed islands of the Uros, Lake Titicaca

Under each island are big blocks of reed roots, tangled together.

Families tie the blocks together with grass ropes. Then they pile cut reeds on top, layer after layer. Poles and heavy stones keep the island from drifting away.

The base of most Uro islands is made of q'illi: blocks of totora roots and stems, tangled tightly together, which float. Each block is about 3 by 4 meters and 30 to 40 centimeters thick. Builders tie the blocks together at the corners with ropes made of ichu grass, making a floating platform of 300 to 400 square meters.

On top go layers of reeds: about 2 meters of fresh totora, then about 1 meter of dry totora. A wall built around the edge holds the filling in. Eucalyptus poles pushed into the lake bed and stone anchors on the bottom keep the island in place. Building one takes three to six months.

The resolution distinguishes two island types. Type B, the most numerous today, rests on blocks of q'illi, a mass of interlaced totora rhizomes. Blocks of about 3 x 4 m and 30-40 cm thick are lashed at the corners with ichu-grass ropes in a zigzag, giving surfaces of 300-400 m². Fresh totora is laid to about 2 m, then about 1 m of dry totora, held by a pircado (an edge wall). Eucalyptus poles driven into the lakebed beside the blocks, and stone anchors on the bottom tied to the platform, fix the island in place. Construction takes three to six months.

Type A islands were built on totora rafts joined side by side and covered with cut reeds; at first one or two families lived on each. The resolution says this type has practically disappeared because its structure is fragile.

Families add fresh reeds to their island again and again.

In the rainy season, they do it about twice a month. People who live there say an island can last for many years.

An island made of plants needs care. Peru's 2013 heritage document says families maintain their islands about twice a month in the rainy season, and two to three times a month in the dry season. The reed layer may be replaced up to three times in a year.

Islanders say that an island built on q'illi blocks can last up to 40 to 50 years. Peru calls this the Uros' ancestral knowledge of totora.

Maintenance figures in the resolution: twice a month in the rainy season and two to three times a month in the dry season, with the totora layer replaced up to three times a year. Residents say a Type B island can last up to 40 to 50 years.

The resolution protects this as knowledge and practice, the 'ancestral knowledge and practices of totora management', rather than as any single island. It also notes that boats of totora do not pollute the lake, in contrast with motor boats, and says islands of the older Type A decay as the totora rots and under the harsh climate, sometimes breaking apart.

On the islands, houses are made of reeds too.

Families also make reed boats. They use them to fish, to collect birds' eggs and to travel across the water.

Totora is not only for the islands. Houses on the islands are also built of totora. Today, the resolution says, they are often round with cone-shaped roofs, made of totora, metal sheets or both.

Uro families also build boats from bundles of dried reeds tied together, which Britannica calls balsas. They use them to fish, to hunt, to gather birds' eggs and to travel. A reed mat can serve as a sail, and a boat can even be a place to sleep for a night.

The resolution describes houses of totora, today often cylindrical with conical roofs of totora and/or corrugated metal (calamina). Totora boats serve for fishing, hunting, collecting lake birds' eggs and transport, and as a temporary place to sleep; a totora mat acts as the sail and shades food taken from the lake (fish, eggs and birds).

Britannica describes the balsas as boats of bundles of dried reeds lashed together, made by the Uru and other lake dwellers, and says the Uru live on floating mats of dried totora that grows in dense stands in the marshy shallows. It also lists the lake's native fish as two kinds of killifish (Orestias) and a catfish, with trout introduced from 1939, and a large frog (Telmatobius) in the shallows.

Today, visitors come to see the islands.

Island families make reed boats and sew cloth, some of it to sell. In 2018, Peru said it would help bring back the Uros' own language, Uru.

Life on the islands mixes old knowledge and new things. Houses may have metal roofs as well as reed ones, and visitors come to see the islands. A Britannica video shows island residents finishing a small reed boat and embroidering cloth to sell to visitors.

The Uros' own language, called Uru or Uruquilla, is endangered. In 2018, Peru's Minister of Culture said the ministry would work to recover it, with help from older community members and from Uros living in Bolivia, where the language is still kept.

The opened sources give glimpses rather than a census. Britannica's video caption shows residents of floating totora islands crushing grain with a saddle quern, embroidering cloth for sale to tourists and finishing a small reed boat. The heritage resolution records modern materials alongside traditional ones, such as corrugated metal on house roofs.

Language is a current concern. In February 2018 the state news agency Andina reported Minister of Culture Alejandro Neyra saying the ministry would work to revalue the Uros' cultural expressions, one of these tasks being the recovery of the endangered Uru (Uruquilla) language, working with elders and with Uros in Bolivia, who still keep the language. This topic does not give a population figure, because no official count was opened.