LE3 .A278 1976

1976

Smith, Peter

Acadia University

Master of Science

Masters

Biology

Biology

This thesis examines the relationships among substrates, invertebrates and five species of migrant shorebirds in spring, late summer and autumn, 1976 and 1977, in a macrotidal environment comprised of extensive mud- and sandflats in the Southern Bight, Minas Basin, Bay of Fundy. The most abundant potential prey species were the amphipod Corophiwn volutator (Pallas) and the polychaetes Heteromastus filiformis (Clarapede) and Spiophanes bombyx (Clarapede). Corophiwn was most abundant in well drained sandy substrates whereas Heteromastus was common in various substrate types. Spiophanes was restricted to areas composed of fine sands. The large errant polychaetes Nephtys caeca (Fabricius), Glycera spp. and Nereis spp. occurred in muddy substrates. Semipalmated Sandpiper Calidris pusilla (L.) was the most numerous shorebird. Also studies were Black-bellied Plover Pluvialis squatarola (L.), Semipalmated Plover Charadrius semipalmatus (Bonaparte), Short-billed Dowitcher Limnodromus griseus (Gmelin) and Least Sandpiper Calidris minutiUa (Vieillot). The latter species along with Semipalmated Sandpiper and Semipalmated Plover were collectively referred to as "peep". Numbers of foraging Black-bellied Plover were nearly significantly correlated with average densities of large errant polychaetes in the substrate. Dowitcher and peep were not significantly related to average densities of Corophiwn, even though it was the main prey species recovered from the digestive tracts, but numbers of dowitcher were closely associated with average densities of large polychaetes. The lack of linearity in the relationships between numbers of dowitcher and peep and Corophiwn densities may be due to the effect of "ceiling densities 11 of prey as described in European studies of overwintering shorebirds.

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https://scholar.acadiau.ca/islandora/object/theses:3856