rinse their mouths in the water. When provoked, certain populations of these turtles are capable of excreting a foul smelling fluid from pores on the anterior edge of their shells. Life cycle These turtles reach sexual maturity sometime between 4 and 6 years of age. They mate at the surface or under water. A male will hold the female's carapace with its forelimbs and may bite at her head, neck, and limbs. Females may retain sperm for almost a year after copulation. The females lay 8–30 eggs in a clutch and may lay from 2 to 5 clutches each year. The eggs are laid in a nest that is about across at the entrance. Eggs are spherical and average about in diameter. After an incubation period of about 60 days, which may be longer or shorter depending upon temperature, the eggs hatch. Average hatchling carapace length is about and width is also about . Sex of the hatchlings is not determined by incubation temperature. Diseases In the intensive aquacultural industry Chinese softshell turtle are increasingly vulnerable to multiple bacterial diseases. In 2012 Chinese soft-shell turtles were the first turtle species to undergo a large-scale outbreak of bacterial softshell disease, resulting in slower growth and increased fatality. This lead not only to a decline in P. sinensis, but caused severe economic losses to the turtle culture industry. Aeromonas spp., Citrobacter freundii, and Edwardsiella tarda have all been identified as the most significant causative bacterial organisms. Other bacterial pathogens identified have been Chryseobacterium spp., Morganella morganii and Bacillus cereus spp.. Conservation Wild populations are listed as vulnerable on the IUCN Red List. In contrast, the mass farming and release of P. sinensis has been known to lead to hybridization several other unique Pelodiscus lineages, some of which may be their own distinct species, which in turn threatens their gene pool. Relations with humans The Chinese softshell turtle is the most commonly raised species in China's turtle farms. According to the data obtained from 684 Chinese turtle farms, they sold over 91 million turtles of this species every year; considering that these farms represented less than half of the 1,499 registered turtle farms in China, the nationwide total could be over twice as high. These turtles are considered a delicacy in many parts of Asia. Turtle soup is made from this species. In Japan, they may be stewed with hōtō noodles and served