The effect of temperature upon the boring activity and survival of Limnoria (Isopoda).
The effect of temperature upon the boring activity and survival of a sample of Limnoria spp. taken from Southampton Water was investigated experimentally. Both methods used to assess the boring activity showed that the optimum temperature was 20°C., the summer water temperature at Southampton. The boring activity at 10° fell to about a third of its value at 20°. As the sea temperature in Southampton Water is below 10° for 5 months in winter, it is concluded that most of the damage to wooden structures is caused during the summer. The significance of artificial warming of harbours in winter by the effluents of industrial installations is stressed. The survival varied inversely with temperature, but although mortality was low at the coldest temperatures, the animals were immobilized and unable to bore. Comparisons with the death rate during the activity experiment and with a separate study suggest that the presence of wood has the effect of reducing the survival at low temperatures. A stimulation to activity resulting in the depletion of available food reserves is suggested as a possible explanation. L. lignorum was found to be less tolerant of high temperatures than was L. tripunctata. Author's summary. KEYWORDS: Forest products and their utilization \ marine borers \ aquatic organisms \ marine animals \ wood borers \ marine borers \ aquatic organisms \ marine animals \ wood borers \ temperature requirements