Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript.

# Breathing life into fisheries stock assessments with citizen science

## Abstract

Citizen science offers a potentially cost-effective way for researchers to obtain large data sets over large spatial scales. However, it is not used widely to support biological data collection for fisheries stock assessments. Overfishing of demersal fishes along 1,000 km of the west Australian coast led to restrictive management to recover stocks. This diminished opportunities for scientists to cost-effectively monitor stock recovery via fishery-dependent sampling, particularly of the recreational fishing sector. As fishery-independent methods would be too expensive and logistically-challenging to implement, a citizen science program, Send us your skeletons (SUYS), was developed. SUYS asks recreational fishers to voluntarily donate fish skeletons of important species from their catch to allow biological data extraction by scientists to produce age structures and conduct stock assessment analyses. During SUYS, recreational fisher involvement, sample sizes and spatial and temporal coverage of samples have dramatically increased, while the collection cost per skeleton has declined substantially. SUYS is ensuring sampling objectives for stock assessments are achieved via fishery-dependent collection and reliable and timely scientific advice can be provided to managers. The program is also encouraging public ownership through involvement in the monitoring process, which can lead to greater acceptance of management decisions.

## Introduction

Citizen science programs range in the level of responsibility that members of the public have, from those where scientists are contracted to conduct work on the public's behalf, to those where members of the public independently conduct all aspects of the program, including design, implementation, analysis and reporting1. However, programs that enlist members of the public as volunteer data collectors (contributory citizen science programs) are perhaps the most common1. Such programs have been increasingly employed in recent years for monitoring organisms and environments, both terrestrial and aquatic, e.g. for the collection of presence/absence data for plants or animals2,3,4,5,6. These projects are usually aimed at attracting a large voluntary workforce, which can allow the collection of considerable data sets with substantial spatial and/or temporal coverage that would not be feasible for a research organisation without significant cost7,8. A greater quantity of data may increase statistical precision and power in analyses, but there may also be sampling effects that may influence the quality of the data and require investigation, e.g. volunteer's species identification skills and unbalanced sampling effort5,6,9. There are also costs of implementation and maintenance of citizen science programs, e.g. volunteer training, provision of feedback and data analysis. However, they can have long-term cost-effectiveness and lead to benefits that include improved public ownership of a resource and greater acceptance of science and management decisions2,3,4,10.

Aquatic citizen science programs are becoming more numerous and include the monitoring of fish species presence/absence and coral health (e.g. www.reef.org; www.redmap.org.au)11,12. Recreational fishers have also contributed voluntarily to scientific data collection via catch and effort logbooks and surveys and both contributory and collegial fish-tagging studies, e.g. http://info-fish.net/westag13,14,15,16,17,18. In contrast, the collection of representative biological data necessary for age-based fisheries stock assessments is usually conducted by scientists, rather than citizens, via spatially- and temporally-stratified sampling of catches obtained by fishery-dependent means, e.g. participating commercial fishers' vessels, commercial fish markets and boat-ramp surveys of recreational fishers' catch, and/or by fishery-independent means, e.g. aboard research vessels19,20,21,22,23,24,25,26. Other than market sampling of commercial catches, the above approaches are usually expensive, particularly when sampling is required over several years and across a large geographical area. Ways to reduce field costs have included “self-sampling”, where a small number of commercial and/or recreational fishers are recruited to donate samples from their catch, usually with instructions on how to select samples, or by requesting recreational fishers to voluntarily donate samples from their catch to supplement active boat-ramp sampling27,28,29,30,31.

Fisheries-dependent and –independent methods for sampling fish populations can result in different characteristics in the collected data set, due to the way that each method selects samples from a population32,33,34. For example, sampling fish length or age data from the catch of recreational fishers, who often preferentially retain larger “trophy” fish, may result in a total sample that is not representative of the overall population. This could influence derived population parameters and requires evaluation13. While this does not prevent the use of such data, for scientists to not have control over the selection of samples may have contributed to the limited adoption of large-scale citizen science frameworks for recreational fishers to provide biological samples voluntarily. This is despite the potential advantage of reducing collection costs, while achieving required sample size and spatio-temporal representativeness goals. However, with limited budgets, resource management agencies and scientific organisations need to consider all options8.

#### Feedback

An annual newsletter about the progress of SUYS was sent to each recreational fisher who donated skeletons each year, along with a personal letter detailing the biological data (length, age and estimated weight) from the fish they donated and a reward (e.g. t-shirt or hat). The annual newsletter was also distributed to fisheries offices and participating shops and placed on the Department's webpage (www.fish.wa.gov.au/frames).

#### Public online survey

An online survey of the public was conducted in 2011 to gain an understanding of (1) the awareness of recreational fishers of the SUYS program and their willingness to be involved, (2) why fishers did not donate skeletons if they were aware of the program and understood the need for it and (3) whether prizes were seen as an incentive to fishers to donate skeletons. The request to complete the survey was promoted through newspaper articles, on the Department's webpage and to all Recreational Boat Fishing Licence holders. Questions in the survey are detailed in the Results.

### Analysis of change in temporal and spatial coverage of samples prior to and after the commencement of Send us your skeletons

To provide an example of the change in temporal and spatial coverage of samples, prior to and after SUYS commenced and thus using two different approaches to sampling, data for West Australian dhufish from 2004/05 and 2012/13 were chosen. 2004/05 was chosen as a year representative of sampling prior to SUYS commencing as it comprised a year when (1) samples were obtained using traditional approaches of active sampling at fishing clubs and self-sampling largely by enlisted fishers, (2) there was no large-scale media promotion, (3) substantial sampling effort occurred in that year and thus a reasonable number of samples were collected via traditional approaches to be able to present a meaningful comparison and (4) suitable information was available in that year on recreational fisher names and dates of capture to facilitate the comparison. 2012/13 was chosen as an example year of sampling after SUYS commenced as (1) SUYS only commenced part way through 2010/11, thus it did not provide a full year of data, (2) it was based on the almost exclusively voluntary donation of samples (and met other requirements, i.e. sample information including fisher name and date of capture were available) and (3) using data from the most recent year available had allowed time for the program to become established and may have been more representative of such a program in the longer term. Good general location information for each sample has been obtained throughout the period from 2002/03 to 2012/13.

### Cost of fish skeleton collection

Quantification of activities employed in the monitoring and assessment program was conducted for each year between 2002/03 and 2012/13. This included determining the number and employment level of research staff, field trip expenses (e.g. number of staff and field days), laboratory and field equipment required, the number of vehicles leased and number and type of promotional activities. Costs were then applied to each of these activities based on current (2013/14) prices, except for actual costs of promotion of SUYS since 2010/11. This allowed comparison of what the cost at today's prices would be to use the sampling regime adopted in each year prior to SUYS (i.e. using more active sampling of recreational fishers) with that for SUYS (a contributory citizen science program plus limited active sampling). This avoids the effect that changes in costs over time would have, e.g. due to the Consumer Price Index or progression of individual staff members along salary scales.

A year of substantial sampling effort (2004/05), using predominantly active sampling (towards an assessment based on three years of data collection between 2002/03 and 2005/06), was also a year during which the most skeletons were obtained from the recreational sector for a single assessment. This was chosen as a base year against which to compare subsequent annual costs of collection per fish skeleton.

## References

1. Shirk, J. L. et al. Public participation in scientific research: a framework for deliberate design. Ecol. Soc. 17, Article 29 (2012).

2. Cohn, J. P. Citizen science: Can volunteers do real research? Bioscience 58, 192–197 (2008).

3. Bonney, R. et al. Citizen science: A developing tool for expanding science knowledge and scientific literacy. Bioscience 59, 977–984 (2009).

4. Silvertown, J. A new dawn for citizen science. Trends Ecol. Evol. 24, 467–71 (2009).

5. Devictor, V., Whittaker, R. J. & Beltrame, C. Beyond scarcity: citizen science programmes as useful tools for conservation biogeography. Divers. Distrib. 16, 354–362 (2010).

6. Dickinson, J. L., Zuckerberg, B. & Bonter, D. N. Citizen Science as an ecological research tool: Challenges and benefits. Annu. Rev. Ecol. Evol. Syst. 41, 149–172 (2010).

7. Ryan, R. L., Kaplan, R. & Grese, R. E. Predicting volunteer commitment in environmental stewardship programmes. J. Environ. Plan. Manag. 44, 629–648 (2001).

8. Leslie, L. L., Velez, C. E. & Bonar, S. A. Utilizing volunteers on fisheries projects. Fisheries 29, 10–14 (2004).

9. Smith, K. An army of observers. Nat. Clim. Chang. 1, 79–82 (2011).

10. Tulloch, A. I. T., Possingham, H. P., Joseph, L. N., Szabo, J. & Martin, T. G. Realising the full potential of citizen science monitoring programs. Biol. Conserv. 165, 128–138 (2013).

11. Stallings, C. D. Fishery-independent data reveal negative effect of human population density on Caribbean predatory fish communities. PLoS One 4, e5333 (2009).

12. Marshall, N. J., Kleine, D. A. & Dean, A. J. CoralWatch: education, monitoring and sustainability through citizen science. Front. Ecol. Environ. 10, 332–334 (2012).

13. Pollock, K. H., Jones, C. M. & Brown, T. L. Angler Survey Methods and their Applications in Fisheries Management 371 (American Fisheries Society, 1994).

14. Willis, T. J., Millar, R. B. & Babcock, R. C. Detection of spatial variability in relative density of fishes: comparison of visual census, angling and baited underwater video. Mar. Ecol. Prog. Ser. 198, 249–260 (2000).

15. Smith, K. A., Hammond, M. & Brown, J. A Summary of Data Collected by the Angler's Daily Log Book and Fishing Tournament Monitoring Programs in 2004–2006. Fisheries Occasional Publication No. 40 59 (2007). http://www.fish.wa.gov.au/About-Us/Publications/Pages/default.aspx Date of access: 02/04/2014.

16. Kleiven, A. R., Olsen, E. M. & Vølstad, J. H. Total catch of a red-listed marine species is an order of magnitude higher than official data. PLoS One 7, e31216 (2012).

17. Smith, K. et al. Status of Nearshore Finfish Stocks in South-western Western Australia Part 2: Tailor. NRM Project 09003 Final Report. Fisheries Research Report No. 247 108 (2013). http://www.fish.wa.gov.au/Documents/research_reports/frr247.pdf Date of access: 02/04/2014.

18. Ryan, K. L. et al. An Integrated System to Survey Boat-based Recreational Fishing in Western Australia 2011/12, Fisheries Research Report No. 249 168 (2013). http://www.fish.wa.gov.au/Documents/research_reports/frr249.pdf Date of access: 02/04/2014.

19. Russ, G. R., Lou, D. C. & Ferreira, B. P. Temporal tracking of a strong cohort in the population of a coral reef fish, the coral trout, Plectropomus leopardus (Serranidae: Epinephelinae), in the central Great Barrier Reef, Australia. Can. J. Fish. Aquat. Sci. 53, 2745–2751 (1996).

20. Committee on fish stock assessment methods. Improving Fish Stock Assessments 188 (National Academy Press, 1998).

21. Newman, S. J. & Dunk, I. J. Age validation, growth, mortality and additional population parameters of the goldband snapper (Pristipomoides multidens) off the Kimberley coast of northwestern Australia. Fish. Bull. 101, 116–128 (2003).

22. Johnson, T. R. & Van Densen, W. L. T. Benefits and organization of cooperative research for fisheries management. ICES J. Mar. Sci. 64, 834–840 (2007).

23. Fisheries Queensland. Fisheries Long Term Monitoring Program Sampling Protocol - Rocky Reef Fish (2010 Onwards) Section 1 7 (2010). at http://www.daff.qld.gov.au/__data/assets/pdf_file/0010/52966/Rocky-Reef-Fish-SP1-2010-onwards.pdf Date of access: 02/04/2014.

24. Jacobsen, R. B., Wilson, D. C. K. & Ramirez-Monsalve, P. Empowerment and regulation - dilemmas in participatory fisheries science. Fish Fish. 13, 291–302 (2012).

25. Armstrong, M. J., Payne, A. I. L., Deas, B. & Catchpole, T. L. Involving stakeholders in the commissioning and implementation of fishery science projects: experiences from the U.K. Fisheries Science Partnership. J. Fish Biol. 83, 974–996 (2013).

26. Quinn, T. J. & Deriso, R. B. Quantitative Fish Dynamics 542 (Oxford University Press, 1999).

27. Lenanton, R. C., Ayvazian, S. G., Pearce, A. F., Steckis, R. A. & Young, G. C. Tailor (Pomatomus saltatrix) off Western Australia: where does it spawn and how are the larvae distributed? Mar. Freshw. Res. 47, 337–346 (1996).

28. Fairclough, D. V., Dimmlich, W. F. & Potter, I. C. Reproductive biology of the Australian herring Arripis georgiana. Mar. Freshw. Res. 51, 619–630 (2000).

29. Hesp, S. A., Potter, I. C. & Hall, N. G. Age and size composition, growth rate, reproductive biology and habitats of the West Australian dhufish (Glaucosoma hebraicum) and their relevance to the management of this species. Fish. Bull. 100, 214–227 (2002).

30. Marriott, R. J. et al. Age-based demographic assessment of fished stocks of Lethrinus nebulosus in the Gascoyne Bioregion of Western Australia. Fish. Manag. Ecol. 18, 89–103 (2011).

31. Starr, P. Fisher-collected sampling data: Lessons from the New Zealand experience. Mar. Coast. Fish. Dyn. Manag. Ecosyst. Sci. 2, 47–59 (2010).

32. Hilborn, R. & Walters, C. J. Quantitative Fisheries Stock Assessment: Choice, Dynamics and Uncertainty 570 (Chapman and Hall, 1992).

33. Rotherham, D., Underwood, A. J., Chapman, M. G. & Gray, C. A. A strategy for developing scientific sampling tools for fishery-independent surveys of estuarine fish in New South Wales, Australia. ICES J. Mar. Sci. 64, 1512–1516 (2007).

34. Ono, K. et al. The importance of length and age composition data in statistical age-structured models for marine species. ICES J. Mar. Sci. Adv. Access (2014). http://icesjms.oxfordjournals.org/content/early/2014/02/20/icesjms.fsu007.full.pdf+html Feb 20, 2014.

35. Fairclough, D., Lai, E., Holtz, M., Nicholas, T. & Jones, R. West Coast Demersal Scalefish Resource Status Report. In: Status Reports of the Fisheries and Aquatic Resources of Western Australia 2012/13. State of the Fisheries (eds. Fletcher W. J., & Santoro K.) 91–101 (Department of Fisheries Western Australia, 2013). www.fish.wa.gov.au Date of access: 25/08/2014.

36. Department of Fisheries Western Australia. A Strategy for Managing the Recreational Catch of Demersal Scalefish in the West Coast Bioregion Fisheries Management Paper No. 228. 26 (2008). http://www.fish.wa.gov.au/Documents/management_papers/fmp228.pdf Date of access: 25/08/2014.

37. Wise, B. S., StJohn, J. & Lenanton, R. C. Spatial Scales of Exploitation Among Populations of Demersal Scalefish: Implications for Management. Part 1: Stock Status of the Key Indicator Species for the Demersal Scalefish Fishery in the West Coast Bioregion. Fisheries Research Report no. 163 130 (2007). http://www.fish.wa.gov.au/Documents/research_reports/frr163.pdf Date of access: 02/04/2014.

38. Caddy, J. F. & Mahon, R. Reference Points for Fisheries Management. FAO Fisheries Technical Paper No. 347 83 (1995). http://www.fao.org/docrep/003/V8400E/V8400E00.HTM Date of access: 25/08/2014.

39. Caddy, J. F. & Agnew, D. J. An overview of recent global experience with recovery plans for depleted marine resources and suggested guidelines for recovery planning. Rev. Fish Biol. Fish. 14, 43–112 (2004).

40. Crowe, F. M., Longson, I. G. & Joll, L. M. Development and implementation of allocation arrangements for recreational and commercial fishing sectors in Western Australia. Fish. Manag. Ecol. 20, 201–210 (2013).

41. Fairclough, D. V. et al. Status of Demersal Finfish Stocks on the West Coast of Australia. Fisheries Research Report No. 253 92 (2014). http://www.fish.wa.gov.au/Documents/research_reports/frr253.pdf Date of access: 25/08/2014.

42. Integrated Fisheries Allocation Advisory Committee. West Coast Demersal Scalefish Allocation Report. Fisheries Management Paper No. 249 60 (2013). http://www.fish.wa.gov.au/Documents/management_papers/fmp249.pdf Date of access: 02/04/2014.

43. Craine, M. et al. Determination of a Cost Effective Methodology for Ongoing Age Monitoring Needed for the Management of Scalefish Fisheries in Western Australia. Final FRDC Report – Project 2004/042. Fisheries Research Report No. 192 98 (2009). http://www.fish.wa.gov.au/Documents/research_reports/frr192.pdf Date of access: 02/04/2014.

44. Campana, S. Accuracy, precision and quality control in age determination, including a review of the use and abuse of age validation methods. J. Fish Biol. 59, 197–242 (2001).

45. Fisher, E. A., Hesp, S. A. & Hall, N. G. Exploration of the Effectiveness of Alternative Management Responses to Variable Recruitment. Final Report to the Fisheries Research and Development Corporation Project No. 2008/006 167 (2011). http://frdc.com.au/research/final-reports/Pages/2008-006-DLD.aspx Date of access: 25/08/2014.

46. Aanes, S. & Pennington, M. On estimating the age composition of the commercial catch of Northeast Arctic cod from a sample of clusters. ICES J. Mar. Sci. 60, 297–303 (2003).

47. Chen, Y., Chen, L. & Stergiou, K. I. Impacts of data quantity on fisheries stock assessment. Aquat. Sci. 65, 92–98 (2003).

48. Otway, N. & Craig, J. R. Effects of hook size on the catches of undersized snapper Pagrus auratus. Mar. Ecol. Prog. Ser. 93, 9–15 (1993).

49. Alós, J., Palmer, M., Grau, A. M. & Deudero, S. Effects of hook size and barbless hooks on hooking injury, catch per unit effort and fish size in a mixed-species recreational fishery in the western Mediterranean Sea. ICES J. Mar. Sci. 65, 899–905 (2008).

50. Johnson, T. R. Cooperative research and knowledge flow in the marine commons: Lessons from the Northeast United States. Int. J. Commons 4, 251–272 (2010).

51. Duda, M. D. & Nobile, J. L. The fallacy of online surveys: No data are better than bad data. Hum. Dimens. Wildl. 15, 55–64 (2010).

52. Granek, E. F. et al. Engaging recreational fishers in management and conservation: global case studies. Conserv. Biol. 22, 1125–34 (2008).

53. Cooke, S. J. & Cowx, I. G. The role of recreational fishing in global fish crises. Bioscience 54, 857–859 (2004).

54. Smith, K. et al. Status of Nearshore Finfish Stocks in South-western Western Australia Part 1: Australian Herring. Fisheries Research Report No. 246 194 (2013). http://www.fish.wa.gov.au/Documents/research_reports/frr246.pdf Date of access: 02/04/2014.

55. Brown, J., Dowling, C., Hesp, A., Smith, K. & Molony, B. Status of Nearshore Finfish Stocks in South-western Western Australia. Part 3. Whiting (Sillaginidae). Fisheries research Report No. 248 128 (2013). http://www.fish.wa.gov.au/Documents/research_reports/frr248.pdf Date of access: 02/04/2014.

56. Wakefield, C. B., Newman, S. J. & Molony, B. W. Age-based demography and reproduction of hapuku, Polyprion oxygeneios, from the south coast of Western Australia: implications for management. ICES J. Mar. Sci. 67, 1164–1174 (2010).

57. Wakefield, C. B., Newman, S. J., Marriott, R. J., Boddington, D. K. & Fairclough, D. V. Contrasting life history characteristics of the eightbar grouper Hyporthodus octofasciatus (Pisces: Epinephelidae) over a large latitudinal range reveals spawning omission at higher latitudes. ICES J. Mar. Sci. 70, 485–497 (2013).

58. Dedual, M. et al. Communication between scientists, fishery managers and recreational fishers: lessons learned from a comparative analysis of international case studies. Fish. Manag. Ecol. 20, 234–246 (2013).

59. Fairclough, D. The Biology of Four Tuskfish Species (Choerodon: Labridae) in Western Australia (204 (2005). http://researchrepository.murdoch.edu.au/47/ Date of access: 02/04/2014.

60. Wakefield, C. B. Latitudinal and Temporal Comparisons of the Reproductive Biology and Growth of Snapper, Pagrus auratus (Sparidae), in Western Australia. 162 (2006). http://researchrepository.murdoch.edu.au/382/ Date of access: 02/04/2014.

## Acknowledgements

The authors express their gratitude to the many recreational fishers (and the commercial sector) who contributed to the monitoring and assessment of demersal fishes by donating fish skeletons and to the businesses who donated prizes and provided drop-off locations. We are grateful to the many departmental staff who assisted with field and laboratory work, organised media, promotion and production and conducted education programs. ‘Send us your skeletons’ is funded by the Government of Western Australia.

## Author information

Authors

### Contributions

D.F. conceived the study and led the analysis and writing of the paper. J.B. and B.J.C. were major partners in the development of the Send us your skeletons program. B.M.C. and I.K. contributed to the analysis of data. All authors contributed to the construction of the paper.

## Ethics declarations

### Competing interests

The authors declare no competing financial interests.

## Electronic supplementary material

### Supplementary Information

Supplementary Table 1

## Rights and permissions

Reprints and Permissions

Fairclough, D., Brown, J., Carlish, B. et al. Breathing life into fisheries stock assessments with citizen science. Sci Rep 4, 7249 (2014). https://doi.org/10.1038/srep07249

• Accepted:

• Published: