Hulscher J.B. (1974) An experimental study of the food intake of the Oystercatcher Haematopus ostralegus L. in captivity during the summer. ARDEA 62 (3-4): 155-171

Feeding experiments in captivity were carried out in the summer of 1964 to 1967 with Oystercatchers caught on their nests on the island of Schiermonnikoog in the Dutch Waddensea. The birds were fed with Cockles and/or Mussels. When food was available 24 h/day (non-tidal schedule), the feeding rate (ml Mussel flesh/h) was not constant. Although there were large differences between individuals (Fig. 1A), the feeding rate during darkness was generally only slightly below the average daylight figure (0.86). When food was available 5 or 7+ hours around midday and again 5 or 7+ hours around midnight (tidal schedule), the mean feeding rate at night of the three birds tested was 1.45 times as high as that during the day. The daily food intake was independent of the size of the Mussels the birds were feeding upon, all of which were within the range normally taken (Table 3). The daily food intake showed no difference if the birds had 2 X 5, 2 X 7+ or 24 hours available for feeding per day (Table 4). The daily food intake of individuals varied between wide limits, but over longer periods the daily caloric consumption was about constant, while the birds roughly maintained constant body-weight irrespective of whether they were taking Mytilus or Cardium as food source. For a sample of nine birds food intake was measured over long periods. The mean intake of these nine birds varied from 23.5-36.3 (mean 28.8) g Mussel and/or Cockle flesh (ash-free dry weight) per day (Table 6), corresponding with 120-185 (mean 147) kcal/24 h/bird. For a sample of three birds (out of the nine mentioned above), for which a great number of weightings are available, the food intake (F, in kcalj24 h) and the mean body-weight in captivity (We, in grams) were correlated (F = 0.1363Wc28.1085). The gross energy consumption in captivity is 4.3 times as high as the calculated standard metabolic rate.