Peer Review #3 of "Shifting headlines? Size trends of newsworthy fishes (v0.1)"

Abstract

The shifting baseline syndrome describes a gradual lowering of human cognitive baselines, as each generation accepts a lower standard of resource abundance or size as the new norm. There is strong empirical evidence of declining trends of abundance and body sizes of marine fish species reported from docks and markets. We asked whether these widespread trends in shrinking marine fish are detectable in popular English-language media, or whether news writers, like many marine stakeholders, are captive to shifting baselines. We collected 266 English-language news articles, printed between 1869 and 2015, which featured headlines that used a superlative adjective, such as "giant", "huge" or "monster", to describe an individual fish caught. We combined the reported sizes of the captured fish with information on maximum species-specific recorded sizes to reconstruct trends of relative size (reported size divided by maximum size) of newsworthy fishes over time. There was no evidence that relative length or relative weight declined over time either for the overall dataset, or for most subgroups of ecologically similar species (e.g., pelagic gamefish, oceanic sharks), or was linked to risk of extinction, which would have been consistent with a shifting baseline syndrome. However, 'charismatic megafish' (e.g., basking sharks, whale sharks, manta rays) did show a significant decline in the relative size of newsworthy fish over time, reflecting real biological shifts. While landing any individual of the large-bodied 'megafish' in this group may be newsworthy in part because of their large size relative to other fish species, the 'megafish' covered in our dataset were small relative to their own species -on average only 56% of the species-specific maximum length. The continued use in the English-language media of superlatives to describe fish that are now a fraction of the maximum size they could reach, or a fraction of the size they used to be, does reflect a shifting baseline for some species. Given that media outlets are a powerful tool for shaping public perception and awareness of environmental issues, there is a real concern that such stories might be interpreted as meaning that superlatively large fish still abound.PeerJ reviewing PDF | Manuscript to be reviewed 33 Abstract 34 35 The shifting baseline syndrome describes a gradual lowering of human cognitive baselines, as each 36 generation accepts a lower standard of resource abundance or size as the new norm. There is strong 37 empirical evidence of declining trends of abundance and body sizes of marine fish species reported from 38 docks and markets. We asked whether these widespread trends in shrinking marine fish are detectable in 39 popular English-language media, or whether news writers, like many marine stakeholders, are captive to 40 shifting baselines. We collected 266 English-language news articles, printed between 1869 and 2015, 41 which featured headlines that used a superlative adjective, such as "giant", "huge" or "monster", to 42 describe an individual fis...