Nesting success of yearling and older breeders in the Semipalmated Sandpiper, Calidris pusilla

1983 ◽  
Vol 61 (5) ◽  
pp. 1133-1137 ◽  
Author(s):  
C. L. Gratto ◽  
F. Cooke ◽  
R. I. G. Morrison

Approximately 100 pairs of Semipalmated Sandpipers (Calidris pusilla) nested in a 2-km2 area at La Pérouse Bay, Manitoba, each year from 1980 to 1982. The proportion of nesting yearlings in the population varied from 3 to 10% in different years. Some aspects of the breeding biology of pairs containing at least one yearling were compared with those without yearlings. In 1980, a significantly lower proportion of nests of yearlings were successful (hatched at least one chick) compared with older pairs. In 1981 and 1982 no difference was observed. Nest failure was primarily caused by egg predation. No differences in clutch size or nest distribution were found between the two age groups, but eggs were significantly smaller in nests of yearling females and mean hatch date at yearling nests was later.

2004 ◽  
Vol 21 (2) ◽  
pp. 249-252 ◽  
Author(s):  
Carmem E. Fedrizzi ◽  
Severino M. de Azevedo Júnior ◽  
Maria E. Lacerda de Larrazábal

Annually, large flocks of semipalmated sandpiper Calidris pusilla (Linnaeus, 1766) winter along South America coast, between September-April. They store fats in order to moult and return to their breeding grounds. Here, was examined body masses and plumage of adults Semipalmated Sandpipers during the departure month to evaluate the relationship between body mass and plumage. Fieldwork was conducted at Coroa do Avião (7º40'S, 34º50'W), Pernambuco. Birds were trapped in mist-nets between April 1990 and 1997. They were weighed, and aged according to plumage. Adult plumage may be (1) non-breeding, (2) pre-breeding, and (3) breeding. A total of 213 birds were weighed and examined, so that 8.0% (17) presented non-breeding plumage, 54.0% (115) pre-breeding, and 38.0% (81) breeding plumage. As in Semipalmated Sandpiper, 25g is the minimum body mass required to migrate, birds with breeding plumage and most with pre-breeding, were potentially apt to migrate. Non-breeding plumage birds presented smaller body mass. Apparently physiological problems and infestation may be important factors to explain over-summering, i.e., individuals remaining in the wintering grounds during the boreal summer.


2021 ◽  
Author(s):  
Martin Bulla ◽  
Christina Muck ◽  
Daniela Tritscher ◽  
Bart Kempenaers

Biparental care requires coordination between parents. Such coordination might prove difficult if opportunities to communicate are scarce, which might have led to the evolution of elaborate and noisy nest relief rituals in species facing a low risk of predation. However, whether such conspicuous rituals also evolved in species that avoid predation by relying on crypsis remains unclear. Here, we used a continuous monitoring system to describe nest relief behavior during incubation in an Arctic-breeding shorebird with passive nest defense, the semipalmated sandpiper (Calidris pusilla). We then explored whether nest relief behavior provides information about parental cooperation and predicts incubation effort. We found that incubating parents vocalized twice as much before the arrival of their partner than during other times of incubation. In 75% of nest reliefs, the incubating parent left the nest only after its partner had returned and initiated the nest relief. In these cases, exchanges were quick (25s, median) and shortened over the incubation period by 0.1 – 1.4s per day (95%CI), suggesting that parents became more synchronized. However, nest reliefs were not cryptic. In 90% of nest reliefs, at least one parent vocalized, and in 20% of nest reliefs, the incubating parent left the nest only after its returning partner called instantaneously. In 30% of cases, the returning parent initiated the nest relief with a call; in 39% of these cases, the incubating partner replied. If the partner replied, the next off-nest bout was 1 – 4hr (95%CI) longer than when the partner did not reply, which corresponds to an 8 – 45% increase. Our results indicate that incubating semipalmated sandpipers, which rely on crypsis to avoid nest predation, have quick but acoustically conspicuous nest reliefs. Our results also suggest that vocalizations during nest reliefs may be important for the division of parental duties.


2012 ◽  
Vol 90 (9) ◽  
pp. 1181-1190 ◽  
Author(s):  
J.T. Quinn ◽  
D.J. Hamilton

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.


2019 ◽  
Author(s):  
David D. Hope ◽  
David B. Lank ◽  
Paul A. Smith ◽  
Julie Paquet ◽  
Ronald C. Ydenberg

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.


Diabetes ◽  
2018 ◽  
Vol 67 (Supplement 1) ◽  
pp. 1522-P
Author(s):  
CHRISTOPH H. SAELY ◽  
ALEXANDER VONBANK ◽  
CHRISTINE HEINZLE ◽  
DANIELA ZANOLIN ◽  
BARBARA LARCHER ◽  
...  

2020 ◽  
Vol 3 (6) ◽  
pp. 8-11
Author(s):  
Bakaev Zh. N.

According to the authors, the prevalence of SOPR diseases is from 3 to 20%.In a study of 1573 residents of southern China in two age groups who use tobacco and alcohol, the incidence of SOPR was higher among men living in rural areas compared to urban residents. Among women aged 35-44 years, the incidence was higher in urban women, and in the 65-77-year-old group in rural women. In the course of studies in Brazil, among 335 patients older than 60 years, 646 diseases of the SOPR were identified. Similar results were obtained in the analysis of SOPR diseases in the Volgograd region of the Russian Federation


2020 ◽  
Author(s):  
Peter Hicklin ◽  
Cheri L. Gratto-Trevor

2018 ◽  
Author(s):  
Anat Gesser-Edelsburg ◽  
Munawar Abed Elhadi

BACKGROUND Due to the religious proscription, it was found that Arab youths acquire information and view pornography secretly. The internet exposes them to contents that contradict religious and cultural taboos. There are few studies about viewing habits of sexual contents among Arab adolescents and about the way they discuss sexuality. OBJECTIVE to characterize the barriers and difficulties that prevent sexual discourse in Arab society and enable pornography viewing, according to the perceptions of adolescents and mothers. METHODS phenomological qualitative research methods, in-depth interviews with 40 participants. 20 Arab adolescents, sampled by two age groups: 14-16 and 16-18. In addition, 20 mothers of adolescents from both sexes were interviewed. RESULTS The findings indicate that mothers “turn a blind eye” to porn viewing and sexual activity by boys, versus a sweeping prohibition and denial of such behavior by girls. The boys reported viewing porn routinely, whereas girls denied doing so, but admitted that their girlfriends watched porn. The study also found that the boys have guilt feelings during and after the viewing as a result of the clash between modernity and traditional values. CONCLUSIONS It is necessary to find a way to encourage a significant sexual discourse to prevent the violent consequences of its absence in Arab society. A controlled, transparent and critical sexual discourse could help youth make more informed decisions concerning the search for sexual contents, porn viewing and sexual behavior.


Viruses ◽  
2021 ◽  
Vol 13 (3) ◽  
pp. 500
Author(s):  
Zoltan Vajo ◽  
Gergely Balaton ◽  
Peter Vajo ◽  
Peter Torzsa

Background: Data suggest that pediatric patients might react differently to influenza vaccination, both in terms of immunity and side effects. We have recently shown that using a whole virion vaccine with aluminum phosphate adjuvants, reduced dose vaccines containing 6 µg of viral hemagglutinin (HA) per strain are immunogenic, and well tolerated in adult and elderly patients. Here we show the results of a multicenter clinical trial of pediatric patients, using reduced doses of a new, whole virion, aluminum phosphate adjuvanted vaccine (FluArt, Budapest, Hungary). Methods: A total of 120 healthy volunteers were included in two age groups (3–11 years, receiving 3 µg of HA per strain, and 12–18 years, receiving 6 µg of HA per strain). We used hemagglutination inhibition testing to assess immunogenicity, based on EMA and FDA licensing criteria, including post/pre-vaccination geometric mean titer ratios, seroconversion and seropositivity rates. Safety and tolerability were assessed using CHMP guidelines. Results: All subjects entered the study and were vaccinated (ITT population). All 120 subjects attended the control visit on Day 21 (PP population). All immunogenicity licensing criteria were met in both age groups for all three vaccine virus strains. No serious adverse events were detected and the vaccine was well tolerated by both age groups. Discussion: Using a whole virion vaccine and aluminum phosphate adjuvants, a reduction in the amount of the viral hemmaglutinin is possible while maintaining immunogenicity, safety and tolerability in pediatric and adolescent patients.


Author(s):  
Helen Engemann

Abstract Simultaneous bilingual children sometimes display crosslinguistic influence (CLI), widely attested in the domain of morphosyntax. It remains less clear whether CLI affects bilinguals’ event construal, what motivates its occurrence and directionality, and how developmentally persistent it is. The present study tested predictions generated by the structural overlap hypothesis and the co-activation account in the motion event domain. 96 English–French bilingual children of two age groups and 96 age-matched monolingual English and French controls were asked to describe animated videos displaying voluntary motion events. Semantic encoding in main verbs showed bidirectional CLI. Unidirectional CLI affected French path encoding in the verbal periphery and was predicted by the presence of boundary-crossing, despite the absence of structural overlap. Furthermore, CLI increased developmentally in the French data. It is argued that these findings reflect highly dynamic co-activation patterns sensitive to the requirements of the task and to language-specific challenges in the online production process.


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