To understand food webs functioning in intertidal soft-sediments, it is critical to assess the macrobenthic prey fraction accessible to waders. Here we describe a simple core sampler device allowing to directly relating the vertical distribution of macrozoobenthos to waders bill length. Bill length measurements were used as a proxy of probing depth to estimate the amount of food supply accessible. Several metal plates can be inserted in the core sampler at different heights according to the bill length data of the studied species. These data are provided in a literature survey. For each species, the bill length variability is then explicitly taken into account in the estimation of food accessibility. The core is transparent to check for the quality of the sample. It could also be used to estimate a Benthic Habitat Quality index (BHQ) based on characteristics of the vertical structure of the sediment. This multilevel core is easy to build and to adapt to any studied wader species of the intertidal zone, floodplains or other wetlands. The samples are obtained with the same effort as with usual circular cores leading to the possibility to survey large area. With one core sample, the ecological information that can be achieved at once is threefold: 1) benthic community structure (partitioned in several depths), 2) estimate of the accessible food fraction to waders (range of values) and 3) habitat quality index assessment.
Cite this paper
C. Luczak, D. Menu and C. Rolet, "A Multilevel Core Sampler Device to Directly Estimate Food Supply Accessible to Waders," Open Journal of Marine Science, Vol. 3 No. 2, 2013, pp. 52-65. doi: 10.4236/ojms.2013.32A006.
 D. S. McLusky and M. Elliott, “The Estuarine Ecosystem. Ecology, Threats and Management,” Oxford University Press, Oxford, 2004.
 J. Van de Kam, B. J. Ens, T. Piersma and L. Zwarts, “Shorebirds. An Illustrated Behavioural Ecology,” KNNV Publishers, Utrecht, 2004.
 L. Zwarts, “Waders and Their Estuarine Food Supplies,” RIZA Report Van Zee Tot Land 60, Lelystad, 1996.
 L. Zwarts L and J. H. Wanink, “The Macrobenthos Fraction Accessible to Waders May Represent Marginal Prey,” Oecologia, Vol. 87, No. 4, 1991, pp. 581-587.
 J. J. Beukema, “Expected Changes in the Benthic Fauna of Wadden Sea Tidal Flats as a Result of Sea-level Rise or Bottom Subsidence,” Journal of Sea Research, Vol. 47, No. 1, 2002, pp. 25-39.
 S. Degraer, A. Volckaert and M. Vincx, “Macrobenthic Zonation Patterns along a Morphodynamical Continuum of Macrotidal, Low Tide Bar/rip and Ultra-Dissipative Sandy Beaches,” Estuarine, Coastal and Shelf Science, Vol. 56, No. 3-4, 2003, pp. 459-468.
 T. Piersma, P. De Goeij and I. Tulp, “An Evaluation of Intertidal Feeding Habitats from Shorebird Perspective: Towards Relevant Comparisons between Temperate and Tropical Mudflats,” Netherland Journal of Sea research, Vol. 31, No. 4, 1993, pp. 503-512.
 A. Eleftheriou and N. A. Holme, “Chapter 6. Macrofauna Techniques,” In: N. A. Holme and A. D. McInctyre, Eds., Methods for the Study of Marine Benthos, Blackwell, Oxford, 1984, pp. 140-216.
 C. Kraan, J. A. Van Gils, B. Spaans, A. Dekinga, A. I. Bijleveld, M. Van Roomen, R. Kleefstra and T. Piersma, “Landscape-Scale Experiment Demonstrates That Wadden Sea Intertidal Flats Are Used to Capacity by Molluscivore Migrant Shorebirds,” Journal of Animal Ecology, Vol. 78, No. 6, 2009, pp. 1259-1268.
 C. Kraan, J. Van der Meer, A. Dekinga and T. Piersma, “Patchiness of Macrobenthic Invertebrates in Homogenized Intertidal Habitats: Hidden Spatial Structure at a Landscape Scale,” Marine Ecology Progress Series, Vol. 383, 2009, pp. 211-224. doi:10.3354/meps07994
 L. Zwarts and J. H. Wanink, “How the Food Supply Harvestable by Waders in the Wadden Sea Depends on the Variation in Energy Density, Body Weight, Biomass, Burying Depth and Behaviour of Tidal-Flat Invertebrates,” Netherland Journal of Sea Research, Vol. 31, No. 4, 1993, pp. 441-476. doi:10.1016/0077-7579(93)90059-2
 L. Zwarts, “Burying Depth of the Benthic Bivalve Scrobicularia plana (da Costa) in Relation to Siphon-Cropping,” Journal of experimental Biology and Ecology, Vol. 101, No. 1, 1986, pp. 25-39.
 P. Esselink and L. Zwarts, “Seasonal Trend in Burrow Depth and Tidal Variation in Feeding Activity of Nereis diversicolor,” Marine Ecology Progress Series, Vol. 56, No. 3, 1989, pp. 243-254. doi:10.3354/meps056243
 L. Zwarts and A.-M. Blomert, “Why Knot Calidris canutus Take Medium-Sized Macoma balthica When Six Prey Species Are Available,” Marine Ecology Progress Series, Vol. 83, No. 2-3, 1992, pp. 113-128.
 A. F. G. Gerritsen and A. Meiboom, “The Role of Touch in Prey Density Estimation by Calidris alba,” Netherland Journal of Zoology, Vol. 36, No. 4, 1986, pp. 530-562.
 J. H. Wanink and L. Zwarts, “Does an Optimally Foraging Oystercatcher Obey the Functional Response?” Oecologia, Vol. 67, No. 1, 1985, pp. 581-587.
 S. Cramp and K. E. L. Simmons, “Handbook of the Birds of Europe, the Middle East and North Africa. The Birds of the Western Palearctic. Vol III. Waders to Gulls,” Oxford University Press, Oxford, 1983.
 M. Engelmoer and C. S. Roselaar, “Geographical Variation in Waders,” Kluwer Academic Press, Dordrecht, 1998. doi:10.1007/978-94-011-5016-3
 L. Zwarts, J. T. Cayford, J. B. Hulscher, M. Kersten, P. M. Meire and P. Triplet, “Prey Size Selection and Intake Rate,” In: J. D. Goss-Custard, Ed., The Oystercatcher: From Individuals to Populations, Oxford University Press, Oxford, 1996, pp. 30-55.
 A. J. Prater, J. H. Marchant and J. Vuorinen, “Guide to the Identification and Ageing of Holarctic Waders,” BTO, Trings, 1977.
 P. Géroudet, “Limicoles, Gangas et Pigeons d’Europe. Vol I,” Delachaux & Niestlé, Neuchatel, 1982.
 P. Géroudet, “Limicoles, Gangas et Pigeons d’Europe. Vol II,” Delachaux & Niestlé, Neuchatel, 1983.
 P. Hayman, J. H. Marchant and A. J. Prater, “Shorebirds. An identification Guide to the Waders of the World,” Croom Helm, London and Sydney, 1986.
 J. Del Hoyo, A. Elliott and J. Sargatal, “Handbook of the Birds of the World. Vol. 3 Hoatzin to Auks,” Lynx Editions, Barcelona, 1996.
 E. Wymenga, M. Engelmoer, C. J. Smit and T. M. Van Spanje, “Geographical Breeding Origin and Migration of Waders Wintering in West Africa,” Ardea, Vol. 78, 1990, pp. 83-112.
 N. Desroy and L. Denis, “Influence of Spring Phytodetritus Sedimentation on Intertidal Macrozoobenthos in the Eastern English Channel,” Marine Ecology Progress Series, Vol. 270, No. 1, 2004, pp. 41-53.
 R. G. Johnson, “The Vertical Distribution of the Infauna of a Sand Flat,” Ecology, Vol. 48, No. 4, 1967, pp. 571-578. doi:10.2307/1936501
 L. Zwarts and J. H. Wanink, “Siphon Size and Burying Depth in Depositand Suspension-Feeding Benthic Bivalves,” Marine Biology, Vol. 100, No. 2, 1989, pp. 227240. doi:10.1007/BF00391963
 C. J. Reading and S. McGrorty, “Seasonal Variations in the Burying Depth of Macoma balthica (L.) and Its Accessibility to Wading Birds,” Estuarine, Coastal and Marine Science, Vol. 6, No. 2, 1978, pp. 135-144.
 L. Zwarts and J. H. Wanink, “How Oystercatchers and Curlews Successively Deplete Clams,” In: P. R. Evans, J. D. Goss-Custard and W. G. Hale, Eds., Coastal Waders and Wildfowl in Winter, Cambridge University Press, Cambridge, 1984, pp. 69-83.
 R. R. Sokal and F. J. Rohlf, “Biometry,” 3rd Edition, Freeman, New York, 1995.
 H. C. Nilsson and R. Rosenberg, “Benthic Quality Assessment of an Oxygen Stressed Fjord by Surface and Sediment Profile Images,” Journal of Marine Systems, Vol. 11, No. 3-4, 1997, pp. 249-264.
 N. Spilmont, L. Denis, F. Artigas, F. Caloin, L. Courcot, A. Creach, N. Desroy, F. Gevaert, P. Hacquebart, C. Hubas, M.-A. Janquin, Y. Lemoine, C. Luczak, A. Migné, M. Rauch and D. Davoult, “Impact of Phaeocystis globosa Spring Bloom on the Intertidal Benthic Compartment in the Eastern English Channel: A Synthesis,” Marine Pollution Bulletin, Vol. 58, No. 1, 2009, pp. 55-63.