44 SEPTEMBER 2016 • WORLD AQUACULTURE • WWW.WAS.ORG competition was organized where entries from farmers are judged by their peers and the outcomes considered for ongoing oyster breeding programs. Competition Methods Beginning in 2006 a “Most Beautiful Oyster Competition” has been held in conjunction with annual NSW oyster industry field days. Generally, two gatherings are held within days of each other on the mid-north and south coasts of NSW. Each gathering routinely attracts in excess of 100 industry participants from an industry with some 330 permit holders. Interested farmers are invited to submit six unopened oysters for display in any given class. Classes initially included Sydney rock oyster stick-cultivated, Sydney rock oyster single seed (cultchless cultivation), Pacific oysters and flat oysters. The inclusion of some classes for judging at each field day was constrained by species cultivation range. Prizes were awarded for Sydney rock oysters at all field days, but submission of Pacific oysters was initially limited to northern gatherings because cultivation of this species was prohibited until 2008 in all southern estuaries (O’Connor and Dove 2009). In contrast, flat oyster submissions were largely limited to south coast field days because there is currently little cultivation of the species in central or northern regions of NSW. No restrictions were placed on size or age of oysters submitted within any given class. Application of cosmetics was strictly banned and no special presentation tools, such as soft lighting, silver platters or garnishes were permitted. Oysters were delivered to officials on the morning of the competition, who numbered submissions and displayed oysters, unopened, within classes for the duration of the field day. On each field day participants were allowed one vote in each class. Participants were given no information on the source (origin or producer) of the oysters but were permitted to handle oysters before votes were recorded on official ballots and placed in a sealed voting box. At the end of each field day, votes were tallied and awards presented to those entries judged by oyster industry participants to be the “most beautiful.” Before display, each oyster in each entry was photographed, weighed (±0.1 g) and measured (APM, DVM and width ± 0.5 mm) and the results recorded for later analysis. Competition Results and Discussion Over a four-year period, 64 Sydney rock oysters, 32 Pacific oysters and 8 flat oysters were submitted and a total of 472, 226 event participants and 81 oyster industry participants voted in each class. A synopsis of the results is presented in Table 1. It is evident that NSW oyster farmers showed marked preferences in both the oysters they submitted as being representative of their best and in their choice of overall champions within each class. The measured characteristics (weight, size and shape) of the winning oysters differed among species. Sydney rock oysters The overwhelming majority of Sydney rock oyster entries were from cultchless production systems, either hatchery produced spat, or wild-caught seed scraped from collectors at a small size (<10 mm). Only three “stick” grown entries were submitted and, as a result, data for these oysters were not analysed and this category was ultimately excluded from the two 2009 field days. All but 11 of the 64 Sydney rock oyster entries were heavier “plate grade” oysters (>60 g) in preference to the smaller, more commonly produced “bottle” (50 g) and “bistro” (55 g) grade oysters that constitute over 75 percent of NSW oyster production. None of the lighter entries received a prize. Indeed, the lowest mean weight of a prize winning entry was 78 g per oyster and the average weight for prize winning oysters was over 90 g, approximately 17 g heavier than the mean weight of all the Sydney rock oyster entries submitted. Although heavier, the mean size of the winning entries differed little from the overall mean size of all entries. The uniformity of the six oysters submitted as an entry was thought to be a factor that might contribute to their perceived “beauty”. However this was not clearly evident because the mean CV for oyster weight and height for winning entries was very similar to the mean for all entries. The mean coefficient of variation (CV) for oyster weight (11 percent) and height (4 percent) among the winning entries differed little from that of the mean for all entries (11 and 5 percent, respectively) and no significant correlation was observed between the CVs for individual entry weights and votes received (r = 0.44) or sample heights and votes received (r = -0.29). To date, there has been no attempt to describe the ideal TABLE 5. A synopsis of data collected for Sydney rock, Pacific and flat oysters submitted for “The Most Beautiful Oyster” competition, 2006 - 2009. N Mean Mean Mean Mean Ratio (H:L:W) weight height length width (g) (mm) (mm) (mm) (APM) (DVM) Sydney rock oysters (all) 64 73.2 88.3 65.4 23.5 3:2.22:0.80 Sydney rock oysters (winners) 8 90.9 85.1 64.9 26.3 3:2.29:0.93 Pacific oysters (all)* 32 123.4 101.1 63.3 35.9 3:1.87:1.06 Pacific oysters (winners) 6 97.2 89.9 55.1 32.4 3:1.84:1.03 Flat (all) 8 97.9 92.0 87.5 25.8 3:2.85:0.83 * Excludes weight and measurement data from three entries in which individual oyster weights exceeded 250 g. These submissions were not among the winners.
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