Understanding the past to plan for the future

In order to plan for the future it is important to consider how things have changed from the past. This gives a historical perspective and can be done using fisher knowledge. As part of her PhD Clara looked at fishers’ perceptions of change in the stocks. Particularly, at potential changes that fishers might have observed in blue swimmer crab size and abundance, among other factors, and how these perceptions change with age and/or fishing experience (also called Shifting Baseline Syndrome).

To look at this Clara has been talking catches with long-time crab fishers to see how the abundance of crabs has changes over longer time periods and comparing these trends against articles in newspapers and other sources.

These historical changes and shifting baselines were the focus of the Applied Marine Environmental History in the Indo-Pacific: Problems, Sources and Opportunities workshop, held at very conveniently at Murdoch University. The workshop was held in December 2019 and is organised every few years. This year 27 scholars participated, from Australia, as well as overseas, including Dr Ruth H. Thurstan from the University of Queensland, and Dr Dirk Zeller from the Sea Around Us Project.

Clara presented a 15 minute talk on the perceptions of change in the blue swimmer crab fishery in the south-west coast of Western Australia. Specifically, she presented the data collected during three different field seasons in 2017, 2018 and 2019, during which she conducted over 180 face to face interviews, and collected over 500 responses through an online survey.

Results showed that i) blue swimmer crabs are generally perceived to be smaller and less abundant, particularly in the Peel-Harvey Estuary; ii) fishers believe that the worst decade for blue swimmer crab fishing has been from 2010 to 2019; iii) a massive increase in the number of recreational fishers was reported, particularly in the Peel-Harvey Estuary.

The next steps on Clara’s research will be to understand if these perceptions coincide with quantitative records on changes in size and abundance of blue swimmer crabs in this region. Watch this space for more news!