Withering abalone syndrome is a disease of the abalone shellfish, primarily found in Haliotis cracherodii. It has been recorded from the coasts of California and Baja California.[1]
The diease is caused by the bacterium "Candidatus Xenohaliotis californiensis", which attacks the digestive tract and glands. It causes general lethargy and for the characteristic "foot" to atrophy.[2] This impairs the abalone's ability to adhere to rocks, making it far more vulnerable to predation.[1] The bacteria are believed to be transmitted along the fecal–oral route and through the water column.[1][2]