There is a growing number of known water filled caves in the Dominican Republic, spread all over the island. Santo Domingo, Pedernales, Cabrera, and Bayahibe are some of the regions with underwater caves. Active exploration is being conducted by the Dominican Republic Speleological Society (DRSS) which is working together with local institutions as well as international scientists to further explore all the cave systems possibilities, while focusing on its preservation. El Toro, which is about 6,000 ft (1,800 m) in length, is the longest known cave. Cueva Taina, el Tildo, el Chicho, and el Dudu, the best known caves in the island, have easy access to the water and are considerably safe outside the water as they are in private properties or national parks. Over the past 3 years, the DRSS team together with international scientists have found a new species of bacteria, a number of new and extinct bat species, evidence of extinct crocodiles, and fossils and remains of ancient cave life, such as long extinct monkeys. Furthermore over 120 new springs all over the island, many with caverns and cave systems attached, have been discovered by the DRSS. Safety concerns in Dominican Republic An important safety issue on the island is untrained cave diving, principally lead by unprofessional dive stores and guides risking their customers lives. Unprofessional and unsafe practices of dive guides may be reported to the relevant dive agency and to DRSS.