Demography of a ground nesting bird in an urban system: are populations self-sustaining?

Urbanization poses threats to earth’s biota, and retention of remnant native habitat in protected areas within expanding urban boundaries may help alleviate threats to wildlife. However, it is unclear for nearly all nonsynanthropic (i.e., not benefiting from an association with humans) species whether vital rates in urban habitats can sustain populations or if populations persist only through immigration from outside the urban boundary. We conducted a three-year study of spotted towhees (Aves: Pipilo maculatus) breeding in four undeveloped parks in Portland, OR, USA, to measure park-specific seasonal reproductive output (F) and annual adult survival (S_A). We developed a stochastic model that combined F and S_A with an estimate of first-year survival to measure population growth rate (λ) in all parks assumed to be closed to immigration. F differed among parks but S_A did not. Relatively high F was possible because many pairs raised >1 brood/season. When combined with empirical estimates of survival through the 30-day period of post-fledging parental care (S_D = 0.645), only 2 of 4 parks were self-sustaining (i.e., λ > 1.0). However, S_D reflected substantial loss of fledglings to domestic cats (Felis catus). Assuming no loss to cats and either partial compensatory or additive mortality of fledglings substantially improved prospects of population persistence for declining (sink) populations. Moreover, allowing low levels of immigration to sinks reversed population declines in most parks even when vital rates were insufficient to maintain populations. Our results suggest that nonsynanthropic bird species can persist in urban landscapes, but also that offspring mortality in the post-fledging period may be a critical determinant of population viability.     

Assessing the diversity of the benthic oligochaete communities in urban and woodland ponds in an industrial landscape (Upper Silesia,southern Poland)

Studies were carried out in two mining pond complexes in an industrial landscape. The first complex (consisting of six ponds) was located in an urban area and the second one (consisting of six ponds) in a woodland area. The aims of the study were to assess the diversity of benthic oligochaetes and to evaluate which environmental variables are most important in determining variations in the community structure in ponds of varying location. In total, 21 oligochaete species were recorded (7–11 in the urban ponds, 11–15 in the woodland ponds). Aulodrilus pluriseta, Aulodrilus japonicus and Ophidonais serpentina were only found in the woodland ponds, while Potamothrix bavaricus only occurred in the urban ponds. Limnodrilus hoffmeisteri, Limnodrilus claparedeanus, Chaetogaster diaphanus and Ophidonais serpentina dominated in the woodland ponds, whereas Limnodrilus hoffmeisteri, Limnodrilus claparedeanus, Potamothrix bavaricus and Tubifex tubifex prevailed in the urban ponds. The total density of oligochaetes was higher in the urban ponds thought the values of the diversity indices were higher in the woodland ponds. The local diversity of the ponds was high, while the among-site diversity made only a small contribution to the regional diversity. Nonetheless, a cluster analysis divided all of the ponds into two distinct groups depending on their location. CCA analysis showed that conductivity, pH, total hardness, alkalinity, the concentration of chlorides and the content of organic matter in the bottom sediments were most associated with the distribution of some oligochaete species among the ponds studied.     

Does urbanization affect the seasonal dynamics of bird communities in urban parks?

The environmental factors affecting the spatial dynamics of bird communities in urban parks are well understood, but much less attention has been paid to the seasonal dynamics of bird communities. Since migrant and resident human commensal birds might have contrasting responses to environmental factors of urban parks, we expected different seasonal dynamics among parks. On the other hand, because bird species can have different habitat relationships throughout the year, we also expected different responses of bird richness to environmental variables between breeding and non-breeding seasons. Bird surveys were conducted in 14 small urban parks (1–4 Ha) of Mar del Plata city (Argentina) for one full annual cycle. Bird richness changed between seasons, but bird abundance remained constant. Bird community composition did not vary between seasons, but urban parks near the urban center, with the highest pedestrian traffic and isolation to other green areas had the least seasonal change of composition. During the breeding season, bird richness was negatively affected by the percentage cover of high buildings surrounding the immediate limits of parks, whereas during the non-breeding season bird richness was not related with any environmental variable. Bird composition variation among parks was affected by the distance to the urban center during both seasons. Results showed that urbanization promotes a seasonal homogenization of bird communities in urban parks, probably by affecting the presence of migrant species and promoting the temporal stability of human commensal species.     

Assessing the contribution of fallen autumn leaves to airborne fungi in an urban environment

Urban Ecosystems - Many street trees in urban areas are deciduous and drop leaves during autumn. These leaves are a potential growing substrate for fungi, which when aerosolized and inhaled, can...     

Social Skills in Children Adopted From Socially-Emotionally Depriving Institutions

This study assessed social skills in post-institutionalized (PI) children with respect to age at adoption, age at assessment, and gender. Parent ratings of social skills (Social Skills Rating System) and behavior problems (Child Behavior Checklist) were obtained for 214 children and 127 adolescents who were adopted from socially-emotionally depriving Russian institutions. Results showed that children adopted before 18 months of age have better social skills than those adopted after this age; those assessed in childhood demonstrate better social skills than those assessed in adolescence. PI females, especially later-adopted adolescents, have particularly poor social skills. Children with poor social skills tend to have higher rates of behavior problems.     

Male gamblers – suicide victims and living controls: comparison of adversity over the life course

The objective of this research is to investigate the possible difference in accumulation of adversity over the life course among decedent gamblers and living control gamblers in the province of Quebec, Canada. A sample of 90 adult men, 41 living participants and 49 suicide decedents, met the criteria for at-risk and problem gambling over the last five years. Data were obtained from informants in the case of suicide and directly from living controls during semi-structured face-to-face interviews using SCID I and II, SOGS, Module K and a recount of life trajectories methodology. The results showed a high level of adversity throughout the life trajectories of both groups. However, the living gamblers faced more difficulties during their lifespan than the suicide victims. In the last six months before their death, suicide victims had a significantly higher number of mental health disorders, especially co-morbid mental health disorders and anxiety, compared to the living controls. We also observed a rapid escalation of difficulties, more life events and more psychological distress in the last six months of their lives among the suicide decedents. Suicidal behaviour needs to be carefully investigated by medical staff and mental health practitioners, especially when gamblers demonstrate evidence of mental health disorders or financial difficulties.     

Infant–Mother and Infant–Caregiver Emotional Relationships: Process Analyses of Interactions in Three Contemporary Childcare Arrangements

Emotional relationships in infant–mother dyads in families where mothers provided full‐time childcare were compared with those of families where mothers used in‐home childcare providers and family childcare providers (N = 245). Infant relationships with childcare providers were also studied. Emotional relationships were adequate in all three childcare arrangements, but infant–mother dyads in in‐home childcare arrangements displayed healthier emotional relationships than infant–mother dyads in mother care arrangements; no differences in the health of emotional relationships with infants emerged among the three types of childcare providers (mother care, in‐home childcare, family childcare). Infant–mother dyads in in‐home childcare arrangements also displayed healthier emotional relationships than infant–in‐home childcare caregiver dyads, but infant–mother and infant–caregiver dyads were comparable in family childcare families. Emotional relationships in infant–mother and infant–caregiver dyads were not correlated, regardless of the type of childcare.     

Within inequality characteristics and adaptation of immigrants in the United States

Until recently, in works of literature, the assimilation of immigrants had been viewed as an individualistic rather than a community-based process. However, Hatton and Leigh (2011) showed that immigrants integrate to their host country as communities, not as individuals; hence, group characteristics play as much of a role as individual characteristics in terms of adaptation. This paper introduces another dimension to the immigrant adaptation proxies that reflect community-based characteristics. The fundamental assertion of this paper is that inequality can be used as a proxy of adaptation within immigrant groups. Immigrant groups that exhibit income and education distributions similar to those of the natives can be regarded as well-adapted groups, while those who exhibit vastly different distributions should be considered to be groups with limited adaptation. Using the American Community Survey (ACS) 2010 cohort, this paper presents the initial findings of the within-group inequality of immigrants. Then, a cross-sectional regression analysis is employed to analyze the determinants of inequality across these immigrant groups. The results suggest that immigrant community-based characteristics, such as average income, education, and number of years that the immigrants have spent in the US, can indeed explain most of the variation in inequality.     

Dynamic modelling of long-term care decisions

This paper describes and analyzes research on the dynamics of long-term care and the policy relevance of identifying the sources of persistence in caregiving arrangements (including the effect of dynamics on parameter estimates, implications for family welfare, parent welfare, child welfare, and cost of government programs). We discuss sources and causes of observed persistence in caregiving arrangements including inertia/state dependence (confounded by unobserved heterogeneity) and costs of changing caregivers. We comment on causes of dynamics including learning/human capital accumulation; burnout; and game-playing. We suggest how to deal with endogenous geography; dynamics in discrete and continuous choices; and equilibrium issues (multiple equilibria, dynamic equilibria). We also present an overview of commonly used longitudinal data sets and evaluate their relative advantages/disadvantages. We also discuss other data issues related to noisy measures of wealth and family structure. Finally, we suggest some methods to handle econometric problems such as endogeneous geography.     

Assimilation effects beyond the labor market: time allocations of Mexican immigrants to the US

I use the American Time Use Survey from 2003 to 2012 to analyze, from a gender and marital status perspective, how the time Mexican immigrants devote to market work, household production, personal care, and leisure activities compare to the corresponding time allocations of US natives. Furthermore, I estimate the effect of duration of residence in the US on the immigrants overall patterns of time use. Time diary evidence indicates that, upon arrival to the US, Mexican immigrant men devote more time to market work and commuting than comparable non-Hispanic natives, regardless of their marital status. On the other hand, Mexican immigrant women devote the same amount of time to these activities as the non-Hispanic reference groups, irrespective of the marital status. In addition, the trend data show that immigrant men decrease their paid work with years since migration while immigrant women increase it. Estimates indicate that, for married immigrant men there is a tradeoff between market work and household work, whereas for single immigrant men the tradeoff is between market work and leisure. Finally, Mexican immigrant women relinquish mostly passive leisure and sleep time to meet demands of family and market work.