Abstract

Euthanasia is indicated in many stranded large whale cases due to poor health at the time of stranding and/or the gravitational sequelae of respiratory and circulatory collapse.¹ However, there are rare occasions when a stranded whale may present in good apparent health and favorable environmental conditions may facilitate a rescue attempt. Here, we present the case of a live stranded subadult (6.6 m) minke whale (Balaenoptera acutorostrata) that was refloated, satellite tagged, and herded out of Wellfleet Harbor, Massachusetts, USA on 9 November 2017. The only significant abnormality on physical examination was bilateral slow, pendulous horizontal nystagmus. Point-of-care plasma chemistry abnormalities included markedly elevated creatinine and lactate with a mixed metabolic and respiratory acidosis. With insufficient conspecific reference ranges, unclear etiology and permanence of the nystagmus and otherwise good condition of the animal, the decision was made to attempt a rescue. A temporary single pin temperature-depth recording satellite tag was attached to the whale’s dorsal fin. On the incoming tide, the animal was refloated using a pontoon system. The satellite tag transmitted for 83 days following release and the whale traveled a minimum of 11,140 km along previously hypothesized migratory routes to acoustically-identified minke whale habitat in the Caribbean.^2,3 To the authors’ knowledge, this is the first documented survival of a refloated, satellite tagged, and released stranded large whale and the first non-acoustic documentation of a minke whale migratory route and southern habitat in the Western North Atlantic. This case validates the need for a thorough health assessment and telemetry attachment on any stranded whale prior to attempting rescue, but also brings into question the etiology and clinical significance of the observed abnormalities.

* Presenting author

Literature Cited

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