Acute mortality in California tiger salamander (Ambystoma californiense) and Santa Cruz long-toed salamander (Ambystoma macrodactylum croceum) caused by Ribeiroia ondatrae (Class: Trematoda)

Saskia Keller; Constance Roderick; Christopher Caris; Daniel A. Grear; Rebecca A. Cole

doi:10.1016/j.ijppaw.2021.10.008

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Acute mortality in California tiger salamander (Ambystoma californiense) and Santa Cruz long-toed salamander (Ambystoma macrodactylum croceum) caused by Ribeiroia ondatrae (Class: Trematoda)

Saskia Keller·Constance Roderick·Christopher Caris·Daniel A. Grear·Rebecca A. Cole

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Abstract

In early September 2019, a morbidity and mortality event affecting California tiger salamanders ( Ambystoma californiense ) and Santa Cruz long-toed salamanders ( Ambystoma macrodactylum croceum ) in late stages of metamorphosis was reported at a National Wildlife Refuge in Santa Cruz County, California, U.S.A. During the postmortem disease investigation, severe integumentary metacercarial (Class: Trematoda) infection, associated with widespread skin lesions, was observed. Planorbid snails collected from the ponds of the refuge within seven days of the mortality event were infected with Ribeiroia ondatrae, a digenetic trematode that can cause malformation and death in some amphibians. We suggest sustained seasonal high-water levels due to active habitat management along with several years of increased rainfall led to increased bird visitation, increased over-wintering of snails, and prolonged salamander metamorphosis, resulting in a confluence of conditions and cascading of host-parasite dynamics to create a hyper-parasitized state.

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International Journal for Parasitology: Parasites and Wildlife Article

Source-reported bounding extent: 36.9106467256463° to 36.92423384099305° latitude; -121.80971145629881° to -121.80035591125488° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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Saskia Keller, Constance Roderick, Christopher Caris, Daniel A. Grear, Rebecca A. Cole. 2021. Acute mortality in California tiger salamander (Ambystoma californiense) and Santa Cruz long-toed salamander (Ambystoma macrodactylum croceum) caused by Ribeiroia ondatrae (Class: Trematoda). https://doi.org/10.1016/j.ijppaw.2021.10.008

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