RV Corystes CORY 5/06
Cruise plan
| Cruise Info. | |
| Ship name (ship code) | RV Corystes (74RY) |
| Cruise identifier | CORY 5/06 |
| Cruise period | 2006-04-15 — 2006-04-21 |
| Status | Completed |
| Port of departure | Belfast, United Kingdom |
| Port of return | Belfast, United Kingdom |
| Purpose | Fisheries |
| Objectives | Final in a series of 5 surveys in 2006 to assess the Irish Sea cod stock using the egg production method.
Main Objectives: 1. To conduct a plankton survey using a Gulf VII plankton sampler to determine the distribution and abundance of fish eggs and larvae in the Irish Sea, with particular emphasis on cod (Gadus morhua), haddock (Melanogrammus aeglifinus) and plaice (Pleuronectes platessa) eggs. 2. To remove cod-like eggs from fresh plankton samples at sea. To measure, stage and preserve these eggs in ethanol prior to species identification using a DNA technique on return to the laboratory. 3. To collect supplementary sub-surface environmental data using a self-logging package carried on the Gulf VII plankton samplers. 4. To collect surface water samples for analysis of nutrients, chlorophyll and phytoplankton species identification. Narrative: A full grid of 112 stations was completed. |
| Chief scientist | Steven Beggs (Agri-Food and Biosciences Institute) |
| Project | MH003, Irish Sea cod assessments by egg production |
| Coordinating body | CEFAS |
| Ocean/sea areas | |
| General | Irish Sea and St. George's Channel |
| Specific | Irish Sea |
| Track charts |  (0.02 MB) |
| Measurements | |
| Physical oceanography | |
| Surface measurements underway (T,S) | Description: Continuous recording of surface salinity and temperature via Seabird CTD |
| Water bottle stations | Quantity: number of stations = 30 Description: Samples of surface sea water collected during selected tows. Analysed ashore for conductivity to compare with Valeport CTD measurements. |
| CTD stations | Quantity: number of stations = 112 Description: CTD profiles recorded during plankton hauls by a Valeport CTD unit mounted on top of the sampler. |
| Chemical oceanography | |
| Phosphate | Quantity: number of stations = 112 Description: Surface water samples collected at each station for later analysis ashore |
| Nitrate | Quantity: number of stations = 112 Description: Surface water samples collected at each station for later analysis ashore |
| Nitrite | Quantity: number of stations = 112 Description: Surface water samples collected at each station for later analysis ashore |
| Ammonia | Quantity: number of stations = 112 Description: Surface water samples collected at each station for later analysis ashore |
| Silicate | Quantity: number of stations = 112 Description: Surface water samples collected at each station for later analysis ashore |
| Biology and fisheries | |
| Phytoplankton pigs (eg chlorophyll, fluorescence) | Quantity: number of stations = 112 Description: Samples of surface sea water filtered at every station, then preserved by freezing, for subsequent analysis ashore of chlorophyll pigments |
| Phytoplankton | Quantity: number of stations = 38 Description: Samples of surface sea water collected at selected stations (every third), fixed using Lugols iodine, for subsequent analysis of phytoplankton species ashore |
| Zooplankton | Quantity: number of stations = 112 Description: Samples collected using a fine-mesh (80 micro meter) ancillary net attached to the Gulf VII plankton sampler and towed from surface to near bottom in 'V' shaped profile. Zooplankton preserved in formalin for future analysis. |
| Eggs and larvae | Quantity: number of stations = 112 Description: Samples collected using Gulf VII plankton sampler, towed from surface to near bottom in 'V' shaped profile. Eggs and larvae collected in 270 micro metre mesh net. Cod-like eggs picked out and preserved in ethanol for species identification using genetic analysis. Remainder of sample preserved in formalin for identification and enumeration ashore. |
