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J. Cordes

Publications and source records attributed to J. Cordes.

2 recordsLinked to original sources

Distribution of non-breeding great lakes piping plovers (Charadrius melodus) along Atlantic and Gulf of Mexico coastlines: Ten years of band sightings

In 1993, a mark-recapture effort was initiated to band annually all Great Lakes Piping Plover nesting adults and offspring. With voluntary reporting by observers, >430 sightings of 154 individually-marked Great Lakes banded birds were documented on the wintering grounds during 19952005. This paper reports non-breeding distribution and site-fidelity and identifies Critical Habitat units used by this population during the winter. Information obtained through banded bird sightings indicates that the winter range of Great Lakes Piping Plovers extends from North Carolina to Texas, and the Bahamas, with the majority (75%) of reported individuals wintering in Georgia and Florida. About 95% of sightings were near or within federally-designated winter Critical Habitat for Piping Plovers. Within season (52%) and between-year (62%) site fidelity was documented for resightings within 3.5 km of initial sighting. Although breeding pairs do not winter in close association, there is some evidence to suggest that offspring winter closer to the male rather than the female parent (P-value = 0.03), and adult males and females appear to exhibit latitudinal segregation (P-value < 0.001). Females reach the winter grounds before males, arriving in July and staying through April (???9 months) or 75% of the annual cycle. The study is the first to identify winter distribution for the Great Lakes Piping Plover population. The significant proportion of the annual cycle spent on the wintering grounds emphasizes the importance of habitat protection during the non-breeding season for this federally-listed population.

Waterbirds

A comparison of American Oystercatcher reproductive success on barrier beach and river island habitats in coastal North Carolina

American Oystercatcher ( Haematopus palliatus ) numbers along the east coast of the United States are declining in some areas and expanding in others. Researchers have suggested that movement from traditional barrier beach habitats to novel inland habitats and coastal marshes may explain some of these changes, but few studies have documented oystercatcher reproductive success in non-traditional habitats. This study compares the reproductive success of the American Oystercatcher on three river islands in the lower Cape Fear River of North Carolina with that of birds nesting on barrier island beach habitat of Cape Lookout National Seashore. There were 17.6 times more oystercatcher breeding pairs per kilometer on the river island habitat than barrier beach habitat. The Mayfield estimate of daily nest content survival was 0.97 (S.E. ± 0.0039) on river islands, significantly higher than 0.92 (S.E. ± 0.0059) on barrier islands. The primary identifiable cause of nest failure on the river islands was flooding while the main cause of nest failure on the barrier islands was mammalian predation. Fledging success was equally low at both study sites. Only 0.19 chicks fledged per pair in 2002, and 0.21 chicks fledged per pair in 2003 on the river islands and 0.14 chicks fledged per pair in 2002 and 0.20 chicks fledged per pair in 2003 on the barrier islands. Many questions are still unanswered and more research is needed to fully understand the causes of chick mortality and the functional significance of non-traditional nesting habitats for the American Oystercatcher in the eastern United States.

North Carolina