than once per year. Research from NSW has shown that estimates of marine debris accumulation rates are strongly affected by the frequency of sampling. Another complicating factor is related to the sources of the rubbish – it is impossible to know how much historical debris is reworked from the King River (and its delta, bed and banks) compared with how much is new material added to the Harbour by recreational and commercial activities. Therefore, we only have a general comparison of the data between years for most sites. At Meredith St Boat Ramp, for example, a similar clean-up effort and area was undertaken in 2017 and 2018. Table 1 shows the comparison in drink containers between the two years. Table 1. Drink containers found at Meredith St Boat Ramp
Meredith St Boat Ramp Plastic bottles Glass bottles Aluminium cans
2017 90 240 231
2018 37 139 76
At Ocean Beach, 2617 pieces of rubbish were collected last year, while in 2018, 2406 pieces of rubbish were found.
Figure 19. Students from Strahan Primary School participating in the 2018 clean-up. (Photo: A. Wind).
Macquarie Harbour Shoreline Clean-up | Outcomes and Discussion
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