VARIABILITY AND STABILITY IN BENTHOS - 22 YEARS OF MONITORING OFF NORTHUMBERLAND

The macrobenthic fauna at a station 5.5 nautical miles off the Northum berland coast has been monitored since 1972. During the period 1972 to 1981 the fauna exhibited regular cycles of low abundance in spring fo llowed by high abundance the following autumn. suggesting a system reg ulated by density-dependent processes. In 1982, this pattern broke dow n and the system continued to show instabilities lip to at least 1991. The considerable fluctuations in macrofauna abundance in March during this period were positively correlated with phytoplankton abundance t wo years previously (r(2) = 0.55). There is some indication that a sta ble cycle may be re-appearing in the data from 1992. (C) 1996 Internat ional Council for the Exploration of the Sea