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| Yaquina Bay Crab Research |
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In 2003, the Oregon Legislature enacted a new sport shellfish license requirement with all resulting revenues dedicated to enhance enforcement of shellfish regulations (Oregon State Police), public health (Oregon Department of Agriculture) and management, monitoring, research and public education (Oregon Department of Fish and Wildlife (ODFW).
ODFW is using these revenues to re-establish a shellfish program that will, in part, monitor and assess the recreational crab fishery. In 2006, ODFW’s Marine Resources Program in Newport began catch and effort surveys for the recreational crab fisheries in Yaquina and Alsea Bays.
In addition to these efforts, Newport shellfish staff began a sampling project in Yaquina Bay in May, 2007 to collect more specific information about the bay crab resource. The goal of this research is to further our understanding of the recreational crab resource and factors affecting the sustainability of this resource.
The Yaquina Bay crab sampling project is a small part of a larger, multi-year bay crab monitoring and assessment project and was designed to assess and characterize the following factors: temporal and spatial distributions of species compositions, quantities of crab, size distributions, width/weight relationships, sex ratios, shell conditions, microsporidian infection rates, and estuarine environmental factors affecting bay crabs.
Bay Crab Sampling Proceedures
When Sampling takes place
Bay crab sampling began in May 2007. From May through September sampling took place 3 times per month. Each sampling day was a weekday to reduce interference with recreational crabbers. |
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| Bay Crab Sampling |
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The Process
Each sampling day three recreational sized crab pots are set in 4 pre-defined areas in strings parallel to the channel. In each area: salinity, dissolved oxygen and temperature at depth is recorded. Each pot is pulled three times, for a total of 36 retrievals/ sampling day. |
Once the pot is on deck, all crab are removed and placed in labeled buckets to be sampled. |
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| Species |
Identification
Each crab is identfied to species
Each crabs gender is determined |
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| Gender |
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| Weighing a Crab |
Weight and Measurments
All crabs are measured and weighed |
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| Measuring a Crab |
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Microsporidian prevalence sampling
Needle condition - Nadelspora canceri is a microsporidian that infects the muscles of a crab, changing the meat to a white ‘cooked’ color while the crab is still alive. Some people notice a bad taste when eating an infected crab but consuming infected crab meat is not known to be harmful to humans.
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Pink crab – A different type of microsporidian that infects the muscles of a crab can change the meat to a vibrant pink color while the crab is still alive. The pink crab infection rate is very low in Yaquina Bay (less than 1%) and again consuming pink infected crab meat is not known to be harmful to humans.
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At the End of the Day
Finally all crabs are returned, unharmed, back into the bay at the end of the sampling day.
Preliminary results |
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