RRS Challenger CH8/81

Cruise summary report

Cruise Info. 
Ship name (ship code)RRS Challenger (74CH)
Cruise identifierCH8/81
Cruise period1981-05-18 — 1981-06-01
Port of departureBarry, United Kingdom
Port of returnBarry, United Kingdom
Objectives1. To obtain a series of quantitative megabenthos samples using the IOS epibenthic sledge, fitted with a single coarse net, at 500m depth intervals from 500m to 4000m along the western flank of the Sea-Bight to investigate the relationship between megabenthic biomass and depth.
2. To obtain, at these same stations, a series of samples with the SMBA multiple corer to examine the distribution with depth of the meiofauna/macrofauna and chloroplastic pigments within the upper 5cm of the sediments.
3. To obtain a series of Reineck box cores at one depth to compare the meiofauna and chloroplastic pigments results with those obtained from the multiple corer.
4. To deploy Bathysnap and the amphipod trap system several times each.
5. To obtain a number of epibenthic sledge samples using the multiple net system (see Challenger cruise 9/79 report) for qualitative studies of the macro- and megabenthos, particuarly at depths below 2000m.
6. To obtain two metre gravity core samples at 1000, 2000, 3000 and 4000m to investigate the recent geological history of the Sea-Bight.
7. In addition to the photographs taken with the IOS camera during routine sampling with the epibenthic sledge, to obtain a series of overlapping frames using a "Benthos" mini-camera on the sledge to check the distance-run figures provided by the meter-wheel. Since the "Benthos" camera is rated only to 1000m this exercise was limited to the upper part of the transect.
8. To deploy two bottom transponders at once station to allow more accurate positioning of the ship for towed hauls and particuarly for vertical wire work.
Chief scientistAnthony L Rice (Institute of Oceanographic Sciences Wormley Laboratory)
Cruise reportRRS Challenger CH8/81 cruise report ch8_81.pdf (0.62 MB) 
Ocean/sea areas 
GeneralNorth East Atlantic Ocean (limit 40W)
SpecificPorcupine Sea Bight
Track chartsRRS Challenger CH8/81 cruise track — trk2609.html
Biology and fisheries 
Benthic bacteria/micro-organismsQuantity: number of stations = 10
Description: smba multiple cores samples
ZoobenthosQuantity: number of hauls = 16
Description: distribution,biomass determination
Gear research
Other biological/fisheries measurementQuantity: number of deployments = 3
Description: time lapse photography casts
Other biological/fisheries measurementQuantity: number of deployments = 4
Description: amphipod traps