Vieques was founded in 1843 by Francisco Saínz. Vieques is known as "La Isla Nena" (little girl island) and "Isabel Segunda" (Isabel II). t's 21 miles (34 km) long and 3 miles (5 km) wide, and it is 52 square miles (135 square km) in area. It was annexed to Puerto Rico in 1854. Vieques derives its name from the Taino Indian word for small island (bieques). eauty and history merge on this 21 by 4 mile island. Arawak Indians once lived here and it was an infamous heaven for pirates during the 17th century. Various European powers fought for control of Vieques. The Punta Mulas Lighthouse also known as Morropó was built in 1893. This old lighthouse still protects the port, boasts a reflector imported from Paris in 1895, which extends a beam that can be seen from as far as 16 miles. The island is also home of one of Puerto Rico's three bioluminescent bays. The Mosquito Bay (bioluminescent bay) was officially declared the brightest recorded in the world by Guinness Book of World Records 2008, recognized as a National Natural Landmark since 1980, and considered the best example of a bioluminescent bay in the United States. This rare and remarkable phenomenon is caused by millions of luminescent dinoflagellates lighting up when disturbed by movement, leaving a trail of neon blue. The dinoflagellates, a tiny form of marine life, have characteristics of both plants and animals, their size range from about 5 to 2,000 micrometers (0.0002 to 0.08 inch). The water glows when the microorganisms in it are agitated.