Effect of forager density on feeding rates in spring-staging Semipalmated Sandpipers (Calidris pusilla) using different foraging modes

We examined the influence of the density of foragers on feeding rates of Semipalmated Sandpipers (Calidris pusilla (Linnaeus, 1766)) while using different foraging modes at a spring stopover site in Delaware Bay, USA. Using dynamic estimates of interindividual distances obtained at short intervals of time, we explored how forager density affected feeding rates when Semipalmated Sandpipers used visual pecking or tactile probing. Pecking rate significantly increased with interindividual distances, whereas probe rate was not affected by density. Our study also showed that in fast-moving foragers, such as Semipalmated Sandpipers, in which the number of nearby foragers and distance to the nearest neighbour continuously change throughout the foraging bout, pecking rates are more affected by nearest neighbour distance than by the number of foragers in their immediate vicinity. In addition, our study implies that foragers using different foraging modes might be differently affected by nearby competitors perhaps in response to prey disturbance by neighbours.

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Metals in tissues of migrant semipalmated sandpipers (Calidris pusilla) from Delaware Bay, New Jersey

Environmental Research ◽

10.1016/j.envres.2014.05.020 ◽

2014 ◽

Vol 133 ◽

pp. 362-370 ◽

Cited By ~ 11

Author(s):

Joanna Burger ◽

Michael Gochfeld ◽

Lawrence Niles ◽

Amanda Dey ◽

Christian Jeitner ◽

...

Keyword(s):

New Jersey ◽

Delaware Bay ◽

Calidris Pusilla ◽

Semipalmated Sandpipers

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Patterns of Corticosterone Secretion in Migrating Semipalmated Sandpipers at a Major Spring Stopover Site

The Auk ◽

10.2307/4089759 ◽

2001 ◽

Vol 118 (1) ◽

pp. 79-91

Author(s):

Rebecca L. Holberton ◽

Sidney A. Gauthreaux,

Keyword(s):

Stopover Site ◽

Corticosterone Secretion ◽

Spring Stopover ◽

Semipalmated Sandpipers

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Variation in diet of Semipalmated Sandpipers (Calidris pusilla) during stopover in the upper Bay of Fundy, Canada

Canadian Journal of Zoology ◽

10.1139/z2012-086 ◽

2012 ◽

Vol 90 (9) ◽

pp. 1181-1190 ◽

Cited By ~ 24

Author(s):

J.T. Quinn ◽

D.J. Hamilton

Keyword(s):

Diet Composition ◽

Prey Availability ◽

Prey Selection ◽

Bay Of Fundy ◽

Corophium Volutator ◽

Stopover Site ◽

Semipalmated Sandpiper ◽

Calidris Pusilla ◽

Isotope Analyses ◽

Semipalmated Sandpipers

Semipalmated Sandpipers ( Calidris pusilla (L., 1766)) use the upper Bay of Fundy, Canada, as a critical stopover site during their annual fall migration to wintering grounds in South America. While in the area, they feed extensively on mudflat invertebrates. Historically the amphipod Corophium volutator (Pallas, 1766) has been thought to make up the majority of their diet. However, we have recently observed flexibility in foraging behaviour and prey selection by sandpipers. The extent of this flexibility and the current diet composition is unknown. To address these knowledge gaps, we assessed Semipalmated Sandpiper diets using stable isotope analyses of blood plasma and available prey items. Data were collected in two arms of the Bay of Fundy during summer 2009 and 2010. Diets fluctuated between years and sites, but in all cases the diet was much more diverse than previously thought. Polychaetes and biofilm made substantial contributions, and C. volutator was still present in the diet, but at much reduced levels than previously noted. This previously unrecognized inclusion of biofilm in the diet is consistent with recent observations of other calidrid shorebirds. Based on measures of prey availability, there is little evidence of preference for C. volutator.

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Metal and metalloid levels in blood of semipalmated sandpipers (Calidris pusilla) from Brazil, Suriname, and Delaware Bay: Sentinels of exposure to themselves, their prey, and predators that eat them

Environmental Research ◽

10.1016/j.envres.2019.02.048 ◽

2019 ◽

Vol 173 ◽

pp. 77-86 ◽

Cited By ~ 1

Author(s):

Joanna Burger ◽

David Mizrahi ◽

Christian Jeitner ◽

Nellie Tsipoura ◽

Jason Mobley ◽

...

Keyword(s):

Delaware Bay ◽

Calidris Pusilla ◽

Semipalmated Sandpipers

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Mercury, Lead, Cadmium, Cobalt, Arsenic and Selenium in the Blood of Semipalmated Sandpipers (Calidris pusilla) from Suriname, South America: Age-related Differences in Wintering Site and Comparisons with a Stopover Site in New Jersey, USA

Toxics ◽

10.3390/toxics6020027 ◽

2018 ◽

Vol 6 (2) ◽

pp. 27 ◽

Cited By ~ 10

Author(s):

Joanna Burger ◽

David Mizrahi ◽

Nellie Tsipoura ◽

Christian Jeitner ◽

Michael Gochfeld

Keyword(s):

New Jersey ◽

South America ◽

Stopover Site ◽

Age Related ◽

Calidris Pusilla ◽

Semipalmated Sandpipers

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Migrant semipalmated sandpipers (Calidris pusilla) have over four decades steadily shifted towards safer stopover locations

10.1101/741413 ◽

2019 ◽

Cited By ~ 2

Author(s):

David D. Hope ◽

David B. Lank ◽

Paul A. Smith ◽

Julie Paquet ◽

Ronald C. Ydenberg

Keyword(s):

Intertidal Area ◽

Data Set ◽

Stopover Site ◽

Semipalmated Sandpiper ◽

Peregrine Falcons ◽

Distribution Index ◽

Migrant Birds ◽

Calidris Pusilla ◽

Index Value ◽

Semipalmated Sandpipers

ABSTRACTPeregrine falcons (Falco peregrinus) have undergone a steady hemisphere-wide recovery since the ban on DDT in 1973, resulting in an ongoing increase in the level of danger posed for migrant birds, such as Arctic-breeding sandpipers. We anticipate that in response migrant semipalmated sandpipers (Calidris pusilla) have adjusted migratory behaviour, including a shift in stopover site usage towards locations offering greater safety from falcon predation.We assessed semipalmated sandpiper stopover usage within the Atlantic Canada Shorebird Survey dataset. Based on 3,030 surveys (totalling ∼32M birds) made during southward migration, 1974 - 2017, at 198 stopover locations, we assessed the spatial distribution of site usage in each year (with a ‘priority matching distribution’ index, PMD) in relation to the size (intertidal area) and safety (proportion of a site’s intertidal area further than 150m of the shoreline) of each location. The PMD index value is > 1 when usage is concentrated at dangerous locations, 1.0 when usage matches location size, and < 1 when usage is concentrated at safer locations.A large majority of migrants were found at the safest sites in all years, however our analysis of the PMD demonstrated that the fraction using safer sites increased over time. In 1974, 80% of birds were found at the safest 20% of the sites, while in 2017, this had increased to 97%. A sensitivity analysis shows that the shift was made specifically towards safer (and not just larger) sites. The shift as measured by a PMD index decline cannot be accounted for by possible biases inherent in the data set. We conclude that the data support the prediction that increasing predator danger has induced a shift by southbound migrant semipalmated sandpipers to safer sites.

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Habitat risk: Use of intertidal flats by foraging red knots (Calidris canutus rufa), ruddy turnstones, (Arenaria interpres), semipalmated sandpipers (Calidris pusilla), and sanderling (Calidris alba) on Delaware Bay beaches

Environmental Research ◽

10.1016/j.envres.2018.04.028 ◽

2018 ◽

Vol 165 ◽

pp. 237-246 ◽

Cited By ~ 3

Author(s):

Joanna Burger ◽

Lawrence Niles ◽

Christian Jeitner ◽

Michael Gochfeld

Keyword(s):

Delaware Bay ◽

Calidris Canutus ◽

Intertidal Flats ◽

Calidris Pusilla ◽

Semipalmated Sandpipers

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ELASTIC PROPERTIES OF STRAINED FCC AND HCP IRON

International Journal of Modern Physics B ◽

10.1142/s0217979293000469 ◽

1993 ◽

Vol 07 (01n03) ◽

pp. 207-211

Author(s):

T. KRAFT ◽

M. METHFESSEL ◽

M. VAN SCHILFGAARDE ◽

M. SCHEFFLER

Keyword(s):

Energy Cost ◽

Interplanar Distance ◽

Orbital Method ◽

Full Potential ◽

Local Spin Density Approximation ◽

Nearest Neighbour ◽

Density Approximation ◽

Neighbour Distance ◽

Large Lattice ◽

Fcc Phase

Using the full-potential linear muffin-tin orbital method within the local spin-density approximation we analyse the influence of the nearest neighbour distance on fcc(111) or hcp(0001) iron layers. The LDA-LSDA error in describing ferromagnetic phases is determined to be at least 15 mRy/atom. As a consequence of this error, our calculations favour paramagnetic ground states. In this sense, the reported results have some model character. However, our analysis of the elastic energy cost under distortions should hold for transition metals in general. Allowing relaxations of the interplanar distance the fcc phase can become energetically favourable over the hcp phase at large lattice mismatches. The main reason for this behaviour is the enhanced stiffness of the hcp interplanar bonds due to the shortening of the axial c/a ratio.

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