Figure 1
Total marine citizen science (MCS) literature encountered from 2014 to 2018. MCS literature has been experiencing a steady growth in publication since its beginnings in the early 1990s, which is a trend that continues today (9.7 new papers per year, based on a linear model).
Figure 2
Bar plot showing marine citizen science (MCS) literature contributions for the top five contributing researcher countries, ordered from 2014 to 2018. Despite occasional decreases in contributions from major countries, MCS continued to grow through 2018 as a result of the increased diversity of contributing researcher countries.
Figure 3
World map displaying country locations of marine citizen science research published from 2014 to 2018, with European inset. Data points are scaled and colored to indicate total contributions from each country for these years. Although a total of 44 locations are represented, the majority of publications come from only three countries—Australia, the United Sates, and the United Kingdom.
Figure 4
Scatter plot showing the percentage of published marine citizen science (MCS) studies undertaken in temperate/polar, subtropical, and tropical environments respectively. Contrary to common belief, from 2014 to 2018 there has been an overall decreasing trend in tropical MCS studies and increasing trends in subtropical and temperate/polar studies. The decreasing trend in tropical studies from 2014 to 2018 is not significant (p = 0.09, R^2 = 0.67) unless the outlier point from 2017 is removed (p = 0.02, R^2 = 0.96).
Table 1
Table showing marine citizen science study subjects encountered in published literature from 2014 to 2018. The large quantity of un-emblematic subjects may indicate that the charismatic appeal of study subjects is not as critical as previously thought in recruiting volunteers for marine projects.
| MCS species list | |||
|---|---|---|---|
| Study subject | # of studies | Study subject | # of studies |
| Fauna: | 113 | Flora: | 2 |
| Marine mammals | 17 | Mangroves | 1 |
| Cetacea | 16 | Seaweed | 1 |
| Sirenia | 1 | ||
| Saltwater fish | 50 | Other: | 70 |
| Elasmobranchii | 12 | General faunal species | 11 |
| Osteicthyes | 38 | General faunal and floral species | 2 |
| Marine reptiles | 7 | Plankton | 3 |
| Chelonioidea | 6 | Reef ecosystem | 1 |
| Elapinae | 1 | Debris | 31 |
| Sea birds | 10 | Oil | 1 |
| Crustaceans | 6 | Environment | 21 |
| Mollusks | 12 | ||
| Bivalvia | 8 | Emblematic species? | |
| Cephalopoda | 2 | Yes | 59 |
| Gastropoda | 2 | No | 126 |
| Cnidarians | 9 | ||
| Anthozoa | 5 | ||
| Scyphozoa | 4 | ||
| Echinoderms | 2 | ||
Figure 5
Bar plots showing various aspects of marine citizen science (MCS) studies surveyed from 2014 to 2018. Studies that focused on single or multiple faunal species, on coastal water habitats, or on population monitoring were most common. The “other” category listed in study habitats consists of a variety of less-represented categories, including wetlands, estuaries, rocky reefs, and intertidal regions.