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Annual patterns of cold hardiness, total soluble sugars (TSS) and proteins (TSP) were characterised during two consecutive years (May 2003-April 2005) in leaf and bark tissues of olive (Olea europaea L.) 'Gemlik' trees. One-year-old shoots from 13-year-old olive trees were collected each month and exposed to low temperature at 4 degrees C, -5 degrees C, -10 degrees C, or -20 degrees C for 12 h to determine their cold-hardiness (LT50; assessed by electrolyte leakage). A considerable increase in cold-hardiness was observed with decreasing temperature. Leaf and bark tissues exhibited an increase in cold-hardiness during the Autumn, which reached a maximum in mid-Winter, then gradually decreased during the Spring, and reached a minimum in mid-Summer. Results indicated that leaf and bark tissues in both experimental years responded similarly to cold, with a continuous increase in their TSS and TSP contents during field adaptation in Autumn and Winter, which paralleled their cold-hardiness. The annual cycle of TSP from leaf and bark tissue was characterised by one dimensional SDS-PAGE. A seasonal fluctuation was observed in leaf proteins of 66 kDa and 43 kDa, and in bark proteins of 70 kDa, 43 kDa and 16 kDa, which paralleled cold-acclimation. Evaluation of these leaf and bark TSP profiles showed that these polypeptides disappeared in the Summer, followed by their accumulation again during the Autumn and Winter. Moreover, all these polypeptides became less visible during the Spring. The relationships between these five proteins, TSS contents, and cold-hardiness in olive are discussed.

We studied the diet and foraging behaviour of the Great Knot Calidris tenuirostris and to lesser extent of the Red Knot Calidris canutus rogersi and other waders at Roebuck Bay, Broome, Western Australia, in March-May 1991, the period of northward migration. Visual feeding observations, benthic fauna sampling and faecal analysis showed that the diet of Great Knots consisted mainly of bivalves. The total zoobenthic biomass in Roebuck Bay averaged 13.9 g ash free dry mass (AFDM) m-2, of which 5.7 and 6.0 g AFDM m-2 were available (sensu Zwarts et al. 1992) to Red Knots and Great Knots, respectively. The profitabilities of several possible prey types are discussed and compared with the recorded diet. Intake rates of Great Knots were estimated on the basis of recorded prey intake (0.24 mg AFDM s-1) and defaecation rates (0.33 mg AFDM s-1), and used to calculate mass gains prior to northward migration. The repercussions of the large tidal range on foraging possibilities are discussed. Changes in tidal regime may mean that Great Knots do not always have access to their preferred feeding sites. We indicate that the array of prey types available to, and taken by, Great Knots is much greater in Roebuck Bay than in the Wadden Sea. We discuss the repercussions of diet diversity on wader distribution. When compared with other springboard areas such as the Banc d'Arguin in Mauritania and the Wadden Sea in western Europe, the available Roebuck Bay benthic food stocks are larger.