Dataset Information

Shifting headlines? Size trends of newsworthy fishes.

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. We found some evidence of a shifting baseline syndrome in news media over the last 140 years: overall, the relative length of the largest fish worthy of a headline has declined over time. This pattern held for charismatic fish species (e.g. basking sharks, whale sharks, giant mantas), which are now reported in the media at smaller relative lengths than they were near the turn of the 20th century, and for the largest species under high risk of extinction. In contrast, there was no similar trend for pelagic gamefish and oceanic sharks, or for species under lower risk of extinction. While landing any individual of the large-bodied 'megafish' 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.

SUBMITTER: Francis FT

PROVIDER: S-EPMC6378912 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Similar Datasets

Project description:Fish predation is important in shaping populations and community structure in aquatic systems. These predator-prey interactions can be influenced by environmental, behavioural and morphological factors. Morphological constraints influence the feeding performance of species, and interspecific differences can thus affect patterns of resource use. For piscivorous fishes that swallow prey whole, feeding performance has traditionally been linked to three key morphological constraints: oral gape, pharyngeal gape, and the cleithral gape. However, other constraints may be important. We therefore examine 18 potential morphological constraints related to prey capture and processing, on four predatory species (Cephalopholis urodeta, Paracirrhites forsteri, Pterois volitans, Lates calcarifer). Aquarium-based experiments were then carried out to determine capture and processing behaviour and maximum prey size in two focal species, C. urodeta and P. forsteri. All four species showed a progressive decrease in gape measurements from anterior to posterior with oral gape ≥ buccal ≥ pharyngeal ≥ pectoral girdle ≥ esophagus ≥ stomach. C. urodeta was able to process prey with a maximum depth of 27% of the predators' standard length; for P. forsteri it was 20%. C. urodeta captured prey head-first in 79% of successful strikes. In P. forsteri head-first was 16.6%, mid-body 44.4%, and tail-first 38.8%. Regardless of capture mode, prey were almost always swallowed head first and horizontally in both focal species. Most internal measurements appeared too small for prey to pass through. This may reflect the compressibility of prey, i.e. their ability to be dorsoventrally compressed during swallowing movements. Despite examining all known potential morphological constraints on prey size, horizontal maxillary oral gape in a mechanically stretched position appears to be the main morphological variable that is likely to affect maximum prey size and resource use by these predatory species.

Dataset Information

Shifting headlines? Size trends of newsworthy fishes.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets