Reliability of non-expert observer estimates of the magnitude of marine reserve effects

Hassell, Nikki S., Williamson, David H., Evans, Richard D., and Russ, Garry R. (2013) Reliability of non-expert observer estimates of the magnitude of marine reserve effects. Coastal Management, 41 (4). pp. 361-380.

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No-take marine reserves (NTMRs) are being implemented for various conservation and fishery management objectives. Well-designed ecological monitoring programs should accompany the implementation of NTMRs to assess their performance against stated objectives. However, monitoring programs often have limited funding and limited access to experienced ("expert") underwater visual census (UVC) observers. Consequently, use of non-expert, volunteer observers to collect marine ecological data has increased. The need to assess the quality and utility of non-expert data has been acknowledged. Few studies have directly compared expert and non-expert assessments, and these are generally one-point-in-time comparisons. Here we assess the magnitude of NTMR:Non-reserve density ratios for target and non-target reef fish collected in five separate years over a decade (2000–2009) by expert and non-expert observers in the Palm Islands, Great Barrier Reef, Australia. Despite variations in methods and resultant differences in absolute fish density estimates, NTMR:Non-reserve density ratio estimates made by experts and non-experts usually differed by 10% or less. Furthermore, estimates of the statistical significance of reserve effects made by experts and non-experts had at least 80% agreement over the decade. The findings support the notion that UVC data collected by trained non-expert observers can provide reliable information on the magnitude of NTMR effects.

Item ID: 28916
Item Type: Article (Research - C1)
ISSN: 1521-0421
Keywords: fish surveys, Great Barrier Reef, long-term monitoring, non-expert observers, no-take marine reserves
Date Deposited: 21 Aug 2013 05:30
FoR Codes: 07 AGRICULTURAL AND VETERINARY SCIENCES > 0704 Fisheries Sciences > 070403 Fisheries Management @ 50%
06 BIOLOGICAL SCIENCES > 0602 Ecology > 060201 Behavioural Ecology @ 50%
SEO Codes: 96 ENVIRONMENT > 9605 Ecosystem Assessment and Management > 960507 Ecosystem Assessment and Management of Marine Environments @ 100%
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