§ Ann WintertonTo ask the Secretary of State for Environment, Food and Rural Affairs what records she maintains of sea temperature around the various sectors of the British Isles; and what movements in temperature have taken place over the last 20 years. [130366]
§ Mr. BradshawSea temperature data collected for the waters around the British Isles are collated by such national and international bodies as the British Oceanographic Data Centre and the Hydrographic Service of the International Council for the Exploration of the Sea (ICES).
The ICES Working Group on Oceanic Hydrography produces an Annual Ocean Climate Status Summary of the North Atlantic Region, and include long time series from the seas around the British Isles.
Other relevant publications include:
Alcock, G. and Rickards, L. (2001) Climate of UK waters at the millennium: Status and trends. Inter-Agency Committee on Marine Science and Technology, IACMST Information Document, 9, 48 pp.Clark, R. A., Fox, C. J., Ben-Hamadou, R. and Planque, B. (2001) A directory of hydrographic and atmospheric datasets for the north east Atlantic and UK shelf seas. CEFAS, Science Series Technical Report, 113, 43 pp.Round Britain most surface temperature series show a warming trend at a rate of between 0.5°C and 1°C per decade since the 1960s. This warming has largely been driven by a strongly positive phase of the fluctuating atmospheric pattern called the North Atlantic Oscillation (NAO).
§ Ann WintertonTo ask the Secretary of State for Environment, Food and Rural Affairs if she will list the sea temperature bands required by each main species of fish in waters surrounding the British Isles. [130367]
§ Mr. BradshawThe table shows the estimated temperature range associated with several important commercial species:
Common name Scientific name Temperature (°C) Range Cod Gadus morhua 0–20 Haddock Melanogrammus aeglefinus 4–10 Saithe Pollachius virens Temperate Ling Molva molva Temperate Whiting Merlangius merlangus Temperate Monkfish Lophius piscatorius Temperate Salmon Salmo salar 2–9 Bass Dicentrarchus labrax 8–24 Dogfish Scyliorhinus Canicula Sub-tropical Plaice Pleuronectes platessa 2–15 Lemon sole Microstomus kitt Temperate Sole Solea solea 8–24 Herring Clupea harengus 1–18 Mackerel Scomber scombrus 4–14 Sprat Sprattus sprattus Temperate Pilchard Sardina pilchardus Sub-tropical Sandeel Ammodytidae Temperate Note:
References to temperate and sub-tropical in the table indicate that a specified range is not available in the scientific literature.
While a change in sea temperature could affect stock distribution, spawning, migratory patterns and survival of very young fish, the effect of long term temperature trends on fish stocks is not easy to predict. Increased sea temperature has been linked to reduced recruitment (the 1194W numbers of young fish entering the population) in cold-water species such as cod, and improved recruitment in other species such as bass, but the factors influencing the survival of fish are complex and in many cases still poorly understood. For heavily fished species, fishing pressure remains the primary control on stock size but recruitment success also has a significant impact.