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

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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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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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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Sex and age dependent migration phenology of the Pied Flycatcher in a stopover site in the Carpathian Basin

Ornis Hungarica ◽

10.1515/orhu-2015-0010 ◽

2015 ◽

Vol 23 (2) ◽

pp. 10-19 ◽

Cited By ~ 6

Author(s):

Andrea Harnos ◽

Zsolt Lang ◽

Péter Fehérvári ◽

Tibor Csörgő

Keyword(s):

Wing Length ◽

Carpathian Basin ◽

Stopover Site ◽

The Past ◽

Age Related ◽

Phenological Changes ◽

Comprehensive Picture ◽

Migration Phenology ◽

And Gender ◽

Gender Groups

Abstract Very little is known about Pied Flycatchers crossing the Carpathian Basin. We give a comprehensive picture about its migration based on the data collected during the past 26 years (1989–2014) at a stopover site in Hungary: (1) sex and age related phenological changes over the years, (2) sex, age and size dependent migration patterns during and (3) between migration periods, (4) sex and age composition in spring and in autumn and their change over years. The timing of spring migration shifted to earlier dates in the case of males, while that of females did not change implying an increasing rate of protandry. In autumn the timing did not change, but juveniles leave the area earlier than adults. The average wing length increased during the past decades in spring in the case of both sexes. In autumn, wing length did not change significantly during the years, but it increased during the seasons in all age and gender groups. The proportion of males is about 60% in spring and among juveniles in autumn, and it is around 39% in the adult group in autumn. The male ratio diminishes during spring, but it does not change during the autumn season. The average wing of adults is shorter in spring than in autumn. Based on this fact and the different sex ratios in the two seasons we may hypothesize that Pied Flycatchers are loop migrants on this area, and even the sexes of the same population take different routes.

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Malaria infection status of European Robins seems to associate with timing of autumn migration but not with actual condition

Parasitology ◽

10.1017/s0031182018002184 ◽

2019 ◽

Vol 146 (6) ◽

pp. 814-820

Author(s):

Nóra Ágh ◽

Imre Sándor Piross ◽

Gábor Majoros ◽

Tibor Csörgő ◽

Eszter Szöllősi

Keyword(s):

Avian Malaria ◽

Arrival Time ◽

Parasite Prevalence ◽

Malaria Prevalence ◽

Blood Parasites ◽

Autumn Migration ◽

Actual Condition ◽

Infection Status ◽

Stopover Site ◽

Age Related

AbstractAvian malaria parasites can negatively affect many aspects of the life of the passerines. Though these parasites may strongly affect the health and thus migration patterns of the birds also during autumn, previous studies on avian malaria focused mainly on the spring migration and the breeding periods of the birds. We investigated whether the prevalence of blood parasites varies in relation to biometrical traits, body condition and arrival time in the European Robin (Erithacus rubecula) during autumn migration. We found no sex or age related differences in avian malaria prevalence and no relationship between infection status and body size or actual condition of the birds was found either. However, the timing of autumn migration differed marginally between infected and non-infected juveniles, so that parasitized individuals arrived later at the Hungarian stopover site. This is either because avian malaria infections adversely affect the migration timing or migration speed of the birds, or because later arriving individuals come from more distant populations with possibly higher blood parasite prevalence. The possible delay that parasites cause in the arrival time of the birds during autumn migration could affect the whole migratory strategy and the breeding success of the birds in the next season.

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Local Annual Survival and Seasonal Residency Rates of Semipalmated Sandpipers (Calidris Pusilla) in Puerto Rico

The Auk ◽

10.1093/auk/124.4.1397 ◽

2007 ◽

Vol 124 (4) ◽

pp. 1397-1406 ◽

Cited By ~ 2

Author(s):

Susan M. Rice ◽

Jaime A. Collazo ◽

Mathew W. Alldredge ◽

Brian A. Harrington ◽

Allen R. Lewis

Keyword(s):

Puerto Rico ◽

Length Of Stay ◽

Differential Mortality ◽

Caribbean Region ◽

Greater Antilles ◽

Annual Survival ◽

Salt Flats ◽

The Caribbean ◽

Calidris Pusilla ◽

Semipalmated Sandpipers

Abstract We report seasonal residency and local annual survival rates of migratory Semipalmated Sandpipers (Calidris pusilla) at the Cabo Rojo salt flats, Puerto Rico. Residency rate (daily probability of remaining on the flats) was 0.991 ± 0.001 (x̄ ± SE), yielding a mean length of stay of 110 days. This finding supports the inclusion of the Caribbean as part of the species' winter range. Average estimated percentage of fat was low but increased throughout the season, which suggests that birds replenish some spent fat reserves and strive for energetic maintenance. Local annual survival rate was 0.62 ± 0.04, within the range of values reported for breeding populations at Manitoba and Alaska (0.53–0.76). The similarity was not unexpected because estimates were obtained annually but at opposite sites of their annual migratory movements. Birds captured at the salt flats appeared to be a mix of birds from various parts of the breeding range, judging from morphology (culmen's coefficient of variation = 9.1, n = 106). This suggested that origin (breeding area) of birds and their proportion in the data should be ascertained and accounted for in analyses to glean the full conservation implications of winter-based annual survival estimates. Those data are needed to unravel the possibility that individuals of distinct populations are affected by differential mortality factors across different migratory routes. Mean length of stay strongly suggested that habitat quality at the salt flats was high. Rainfall and tidal flow combine to increase food availability during fall. The salt flats dry up gradually toward late January, at the onset of the dry season. Semipalmated Sandpipers may move west to other Greater Antilles or south to sites such as coastal Surinam until the onset of spring migration. They are not an oversummering species at the salt flats. Conservation efforts in the Caribbean region require understanding the dynamics of this species throughout winter to protect essential habitat. Tasas de Supervivencia Anual Local y de Residencia Estacional de Calidris pusilla en Puerto Rico

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Crawling behaviour of the amphipod Corophium volutator and foraging by Semipalmated Sandpipers, Calidris pusilla

Canadian Journal of Zoology ◽

10.1139/z89-066 ◽

1989 ◽

Vol 67 (2) ◽

pp. 457-462 ◽

Cited By ~ 34

Author(s):

J. Sherman Boates ◽

Peter C. Smith

Keyword(s):

Nova Scotia ◽

Food Intake ◽

Lunar Cycle ◽

Intertidal Mudflat ◽

Sharp Reduction ◽

Corophium Volutator ◽

Quantitative Evidence ◽

Qualitative And Quantitative ◽

Calidris Pusilla ◽

Semipalmated Sandpipers

During late spring and summer, the crawling behaviour of the amphipod Corophium volutator was studied on an intertidal mudflat in the Minas Basin, Nova Scotia. On average, less than 1% of the population crawled on any tide and these individuals tended to be large adults that were predominantly males. Animals emerged as the tide receded but most had crawled into burrows after 25 min. The crawling behaviour did not seem to be related to the lunar cycle as was expected; however, there was a sharp reduction in crawling activity (from 36.3 to 1.2 amphipods/m2) in July that coincided with the arrival of Semipalmated Sandpipers, Calidris pusilla, an abundant seasonal predator. The proportion of males in the amphipod population declined during the period when sandpipers were present. It appears that both a change in amphipod behaviour and depletion of the animals most prone to crawling may contribute to the observed reduction in crawling activity. Qualitative and quantitative evidence show that sandpipers were attracted to the tide edge where crawling amphipods were relatively abundant and that they increased their food intake by doing so.

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

The Auk ◽

10.1093/auk/118.1.79 ◽

2001 ◽

Vol 118 (1) ◽

pp. 79-91 ◽

Cited By ~ 3

Author(s):

David S. Mizrahi ◽

Rebecca L. Holberton ◽

Sidney A. Gauthreaux, Jr

Keyword(s):

Fat Mass ◽

Stress Responses ◽

Energy Demand ◽

Corticosterone Concentration ◽

Stopover Site ◽

Handling Stress ◽

Corticosterone Secretion ◽

Julian Date ◽

Energetic Condition ◽

Semipalmated Sandpipers

AbstractSeasonal changes in corticosterone metabolism may be in part responsible for mediating the changes in nutrient reserves before and during migration. To investigate the role of glucocorticoids in the migratory physiology of Semipalmated Sandpipers (Calidris pusilla), we compared plasma levels of corticosterone in response to capture and handling stress during prolonged stopovers in Delaware Bay during spring 1996 and 1997. Although Semipalmated Sandpipers showed significant stress responses to handling in both years, the magnitude of the response was significantly lower in 1997. We found no correlation between energetic condition and initial corticosterone concentration in either year, or between energetic condition and corticosterone concentration in samples collected 30 min after capture in 1996. However, energetic condition was positively correlated with corticosterone concentration in 30 min sample collected in 1997. Between-year differences in regression functions of energetic condition by Julian date suggested that birds were accumulating fat mass more rapidly, or arriving in better energetic condition during 1996 compared to 1997. Those differences were especially evident during the “early” stages (before 26 May) of stopover periods. In 1997, we found that birds sampled early in the season did not show a significant increase in corticosterone 30 min after capture, while birds sampled in early 1996 did. In both years, birds sampled during the “late” stages of stopover periods (after and including 26 May) showed significant stress response. Birds in relatively poor energetic condition, or with low rates of fat-mass gain, were less likely to secrete additional corticosterone in response to acute stress, possibly to protect skeletal muscle needed for migratory flight. Those results suggest that patterns of corticosterone secretion in sandpipers can be modified in response to changes in energy demand during the migratory period.

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Migratory status determines resource selection by American Woodcock at an important fall stopover, Cape May, New Jersey

The Condor ◽

10.1093/condor/duaa046 ◽

2020 ◽

Author(s):

Brian B Allen ◽

Daniel G McAuley ◽

Erik J Blomberg

Keyword(s):

New Jersey ◽

Land Cover ◽

Classification Accuracy ◽

Resource Selection ◽

Radio Telemetry ◽

Stopover Site ◽

Land Cover Types ◽

American Woodcock ◽

Landscape Characteristics ◽

Wetland Forest

Abstract Migration is a period of high activity and exposure during which risks and energetic demand on individuals may be greater than during nonmigratory periods. Stopover locations can help mitigate these threats by providing supplemental energy en route to the animal’s end destination. Effective conservation of migratory species therefore requires an understanding of use of space that provides resources to migratory animals at stopover sites. We conducted a radio-telemetry study of a short-distance migrant, the American Woodcock (Scolopax minor), at an important stopover site, the Cape May Peninsula, New Jersey. Our objectives were to describe land-cover types used by American Woodcock and evaluate home range habitat selection for individuals that stopover during fall migration and those that choose to overwinter. We radio-marked 271 individuals and collected 1,949 locations from these birds (0–21 points individual–1) over 4 yr (2010 to 2013) to inform resource selection functions of land-cover types and other landscape characteristics by this species. We evaluated these relationships at multiple spatial extents for (1) birds known to have ultimately left the peninsula (presumed migrants), and (2) birds known to have remained on the peninsula into the winter (presumed winter residents). We found that migrants selected deciduous wetland forest, agriculture, mixed shrub, coniferous wetland forest, and coniferous shrub, while wintering residents selected deciduous wetland forest, coniferous shrub, and deciduous shrub. We used these results to develop predictive models of potential habitat: 7.80% of the peninsula was predicted to be potential stopover habitat for American Woodcock (95% classification accuracy) and 4.96% of the peninsula was predicted to be potential wintering habitat (85% classification accuracy). Our study is the first to report habitat relationships for migratory American Woodcock in the coastal U.S. and provides important spatial tools for local and regional managers to support migratory and winter resident woodcock populations into the future.

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