Download the latest report to farmers for aquaculture industry statistics and production data.The oyster industry management plan for Moreton Bay Marine Park supports the sustainable development of the commercial oyster industry in Moreton Bay.You will need to discuss technical and licensing aspects of any proposed aquaculture venture with staff from Fisheries Queensland and the Department of Environment and Science proceeding with site selection, design and, where applicable, land purchase.Spatfall occurs throughout the year, but peaks in Moreton Bay between November and March. Known spat-catching areas in southern Queensland are the Great Sandy Strait, Pumicestone Passage and the leeward sides of Moreton, North Stradbroke and South Stradbroke Islands. The batches are placed in the mid to lower part of the tidal range, where the spat settle on the sticks. In this method, 6–8 sticks are nailed to cross-beams to form frames that are then grouped to form batches. Stick placement is one of a variety of proven methods used for collecting spat. The artificial substrate must be attractive to the larvae to encourage them to settle and attach. The influences of tide, wind and currents must be considered before placing spat collection devices. developing a suitable substrate for the spat to settle on.Although many studies have tried to determine exactly what cues the larvae use to settle, it is still not clear. Larvae will die if they do not find a suitable settlement location after this two week period. deciding on an area in which to collect (this must be an area where spat are known to be present in the water) Oyster larvae are competent, or able to settle, for about two weeks.Collecting spatĬrucial considerations for spat collection include: This introduced species competes with rock oysters for food and space. Restrictions are in place to prevent importing the Pacific oyster ( Crassostrea gigas) into Queensland. Selection of spat has become an important issue for Queensland growers, as they need to source supplies of stock that are both economical and contaminant-free. Many growers ask to see a sample of the stock before they buy. Some spat is still collected, but the amount is small compared to the spat sourced from New South Wales.īecause an oyster is considered spat up to the age of 12 months, size can vary considerably. Queensland oyster farmers have, for some time, relied on importing spat from New South Wales for on-growing into Queensland waters. Once settled, they attach and transform into small oysters called spat. The successive steps of growing and maturing depend on the quantity and quality of the spat. they settle, in order to find a suitable spot. Settled oyster spat were counted after each recovery. Bags were replaced every 2 weeks from late June-October. The first step in oyster aquaculture is finding a good source of spat (oyster larvae). Spat Settlement Spatfall was observed using bags (370mm x 300mm / 25mm mesh size) suspended 0.5m off-bottom and containing 20 cleaned oyster shells deployed along 4 stations (Fig.
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