Reinterpreting nineteenth-century accounts of whales battling 'sea serpents' as an illation of early entanglement in pre-plastic fishing gear or maritime debris

Entanglement of whales in active fishing gear and abandoned maritime debris is recognized to be a serious problem in contemporary marine conservation biology, one that is commonly believed to have its origin with the introduction of non-degrading plastic in the mid-twentieth century. As many sightings of purported sea serpents are now acknowledged to have been due to misidentified cetaceans, this anecdotal literature can provide a valuable resource for extending inferences about whale biology backward in time. This article examines this corpus of evidence to suggest that what have been mistakenly believed to have been sea serpents, sighted in both pre- and post-plastic time periods, were in fact sometimes entangled whales. Furthermore, and in particular, what were once a popular staple of nineteenth-century maritime lore - recountings of whales locked in mortal combat with sea serpents - are posited to be the earliest recorded observations existing of large cetaceans entangled in anthropogenic equipment or litter.