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AMPHIBIAN CHYTRIDIOMYCOSISGEOGRAPHIC DISTRIBUTIONHerpetological Review, 2008, 39(2), 192–193.© 2008 by Society for the Study of Amphibians and ReptilesAmphibian Chytridiomycosis in CaptiveAcris crepitans blanchardi (Blanchard’s CricketFrog) Collected from Ohio, Missouri, andMichigan, USAKEVIN C. ZIPPELDetroit Zoo, Royal Oak, Michigan 48068, USACurrent address: Amphibian Ark, 12101 Johnny Cake Ridge RoadApple Valley, Minnesota 55124, USAe-mail: KevinZ@AmphibianArk.organdCHRIS TABAKADetroit Zoo, Royal Oak, Michigan 48068, USACurrent address: Binder Park Zoo, 7400 Division DriveBattle Creek, Michigan 49014, USAe-mail: tortvet@gmail.comAmphibian chytridiomycosis, a disease caused by the fungusBatrachochytrium dendrobatidis (Bd), has been documented innumerous wild populations in North America (Ouellet et al. 2005),including an Illinois population of Blanchard’s Cricket Frog (Acriscrepitans blanchardi) (Pessier et al. 1999). Herein we documentthe possible occurrence of Bd in this species in Ohio in 1999 andthe likely occurrence of Bd in populations from Missouri in 2001and Michigan in 2004.On 16 September 1999, 10 Blanchard’s Cricket Frogs were collectedat St. Mary’s Fish Hatchery in Auglaize County, Ohio, andtransferred to the Toledo Zoo where they spent 10 days in isolationbefore being sent to the Detroit Zoo, Michigan. By 20 September2000, eight frogs had been moved from their quarantineenclosure to a native-Michigan, mixed-species amphibian exhibit.The other two frogs were missing from their quarantine enclosureand presumed dead; it is not unusual for small amphibians to decomposecompletely before their death has been detected, particularlyin naturalistic enclosures. The first two confirmed deathswere over a year after their arrival in Detroit and within months oftheir addition to the mixed exhibit (10 December 2000, 7 February2001); these two frogs tested positive histologically for Bd. Asthe Bd treatment protocol had only recently been published(Nichols and Lamirande 2000) and was not yet known by zoostaff, nothing was done for the animals remaining in the exhibit.Three more frogs died between 27 February 2001 and 10 July2003: histopathology results were inconclusive for two, and Bdwas not detected histologically in the third. Two additional frogswere missing and presumed dead at that time also. On 30 March2003, an American Toad (Anaxyrus americanus) in that exhibitdied; this animal tested positive histologically for Bd. Medicationwith the established protocol (Nichols and Lamirande 2000) wasbegun for the other amphibians in that enclosure in late July 2003.The last cricket frog died on 22 July 2003 while under treatmentfor Bd; there was no histologic evidence of active Bd infection,but there was mild multifocal epidermal hyperplasia likely fromprevious Bd infection. There are two scenarios that could explainthe presence of Bd in this group of cricket frogs from Ohio. Thewild population could be infected and these frogs could have enteredthe collection asymptomatically carrying Bd and graduallysuccumbed over nearly four years. Although some species susceptibleto Bd tend to die within a few weeks of infection, otherscan carry light infections of the disease with no clinical symptomsand only succumb under duress. In this case, the last cricket frogsurvived over two and half years after the first Bd-positive deathin the enclosure. The other possibility is that, since the two positivecases were not detected until after the group was moved intothe mixed-species exhibit, the cricket frogs could have been infectedby the other amphibians in that exhibit, which could havebeen asymptomatic. Two of the three other taxa (Anaxyrusamericanus, Notophthalmus viridescens, but not Lithobatespipiens) eventually tested positive.On 22 October 2001, 10 Blanchard’s Cricket Frogs were collectedfrom Franklin County, Missouri, and transferred to the DetroitZoo. All were dead within four months. Four frogs died inquarantine throughout December 2001; histopathology results wereinconclusive. The remaining six frogs were moved on 2 January2002 into a general holding room with other species but weremaintained in isolation in their own enclosure. Two more frogswere dead by 10 January 2002; histopathology results on thesefrogs were also inconclusive. The seventh frog died on 29 January2002; this frog tested positive histologically for Bd. The remainingthree frogs were dead by 18 February 2002 before we learnedthe results from the seventh frog and had a chance to medicatethem using the established protocol; histopathology results wereinconclusive. The Bd in these animals could have come from poorhusbandry (transmission from other isolated asymptomatic animals),but because these frogs were in an isolated enclosure withdedicated tools during their entire time in captivity, more likelythey came infected from the wild.From 4 August through 7 October 2004, 835 Blanchard’s CricketFrog adults and 176 tadpoles were collected from a wetland inYpsilanti, Washtenaw County, Michigan, where their native habitatwas slated for development. These frogs were held temporarilyin isolated quarantine at the Detroit Zoo, then released into threenewly constructed local wetland sites from 24 August to 7 October2004 (Rickard et al. 2004). Histopathology results from threefrogs and four tadpoles collected and sacrificed a month prior totranslocation revealed no Bd or other diseases. While they were incaptivity, 181 frogs died. Of those, eight were submitted for histopathologyand the last two tested positive for Bd. Because theseanimals were kept in isolated quarantine in a new building withno other amphibians, it is likely that they came infected from thewild.In all three cases, there is a possibility that the Bd in the captivecricket frogs originated from other animals in the captive collection.However, we feel that this is rather unlikely, at least in thetwo cases where the animals were kept isolated from others in thecollection. In the future, we recommend testing for Bd in all amphibiansarriving into captive collections. Not only will this benefitthe health of the captive collection, it can also provide valuabledata on the distribution of Bd in the wild. Bd is not somethingmost zoos test for in quarantine, although a simple PCR test isnow available (Annis et al. 2004) and might someday be afford-192 Herpetological Review 39(2), 2008