Sterlet Sterlet The sterlet ("Acipenser ruthenus") is a relatively small species of sturgeon from Eurasia native to large rivers that flow into the Black Sea, Azov Sea, and Caspian Sea, as well as rivers in Siberia as far east as Yenisei. Populations migrating between fresh and salt water (anadromous) have been extirpated. Due to overfishing (for its flesh, caviar, and isinglass), pollution, and dams, the sterlet has declined throughout its native range and is considered vulnerable by the IUCN. Restocking projects are ongoing, and it has been introduced to some regions outside its native range, but the latter have generally not
Types of beacons Types of beacons Beacons are small devices that enable relatively accurate location within a narrow range. Beacons periodically transmit small amounts of data within a range of approximately 70 meters, and are often used for indoor location technology. Compared to devices based on Global Positioning System (GPS), beacons provide more accurate location information and can be used for indoor location. Various types of beacons exist, which can be classified based on their type of Beacon protocol, power solution and location technology. In December 2013, Apple announced iBeacon: the first beacon protocol in the market. iBeacon works with Apple's iOS and