We study the joint processes of job mobility and wage growth among young men drawn from the Longitudinal Employee-Employer Data. Following individuals at three month intervals from their entry into the labor market, we track career patterns of job changing and the evolution of wages for up to 15 years. Following an initial period of weak attachment to both the labor force and particular employers, careers tend to stabilize in the sense of strong labor force attachment and increasing durability of jobs. During the first 10 years in the labor market, a typical young worker will work for seven employers, which accounts for about two-thirds of the total number of jobs he will hold in his career. The evolution of wages plays a key role in this transition to stable employment: we estimate that wage gains at job changes account for at least a third of early-career wage growth, and that the wage is the key determinant of job changing decisions among young workers. We conclude that the process of job changing for young workers, while apparantly haphazard, is a critical component of workers' move toward the stable employment relations that characterize mature careers.

We study the joint processes of job mobility and wage growth among young men drawn from the Longitudinal Employee-Employer Data. Following individuals at three month intervals from their entry into the labor market, we track career patterns of job changing and the evolution of wages for up to 15 years. Following an initial period of weak attachment to both the labor force and particular employers, careers tend to stabilize in the sense of strong labor force attachment and increasing durability of jobs. During the first 10 years in the labor market, a typical young worker will work for seven employers, which accounts for about two-thirds of the total number of jobs he will hold in his career. The evolution of wages plays a key role in this transition to stable employment: we estimate that wage gains at job changes account for at least a third of early-career wage growth, and that the wage is the key determinant of job changing decisions among young workers. We conclude that the process of job changing for young workers, while apparantly haphazard, is a critical component of workers' move toward the stable employment relations that characterize mature careers.

other sciences, has recently been grasping (some would say "gasping") for relevance. For many sciences, a mere glance from the windows of their ivory towers brought an end to the search for relevancy. Their eyes burned and their vision was limited by the hazylike condition of the atmosphere; they were overwhelmed with the numbers of people, the noises they made, the material they consumed, their trappings and their trash. The landscape was changing rapidly, and the view from the tower was no longer pleasant and the tower itself no longer isolated. The issue of ecology demanded relevance. Indeed, it demanded preeminence. With the problem apparent, scientists began to look for a solution in their typical fashion. Technological solutions were sought for what were defined as technological problems. Thus, the rush is now on to develop new gasolines, new engines, nonpolluting detergents and energy sources, biodegradable products of all kinds, filtering systems and recycling systems, etc. Society appears to have made the assumption that such advances will, indeed, solve the problem.Technology has won battles in the past, in the arenas of medicine, transportation, and automation, but it may not provide the answer to the current ecological crisis. First, the mushrooming nature of 1 This article is based on a paper presented at the annual meeting of the Western Psychological Association, Portland, Oregon, April 1972.

Maloney and Ward (1973) attempted to reconceptualize the ecological crisis, not as a technological problem but as a crisis of maladaptive behavior: "Conceptualized in this manner, the solution to such a problem does not lie in traditional technological approaches but rather in the alteration of human behavior" (p. 583). Such alteration, however, is not feasible, perhaps not even possible, until critical population behaviors are assessed adequately. Consequently, the authors further stressed that we must "go to the people" to understand these behaviors. We must determine what the population knows, thinks, feels, and actually does regarding ecology and pollution. "These are necessary antecedent steps that must be made before an attempt can be made to modify critically relevant behaviors" (p. 584).In a preliminary attempt to provide such data, Maloney and Ward (1973) developed a 128-item1 ecological attitude-knowledge scale that was received with considerable interest and requests to use the scale in a variety of research projects. The present study sought to refine and shorten the original scale in an attempt to provide a more practical and efficient instrument and, second, to make the revised scale publicly available. MethodThe original scale was comprised of four subscalcs: verbal commitment (VC), which measures wbal a person states he is willing to do in reference to pollution-environment issues (31 items); actual commitment (AC), which measures what a person actually does in reference to pollutionenvironment issues (36 items); affect (A), which measures the degree of emotionality related to such issues {37 items);

Approximately two thirds of migratory songbirds in eastern North America negotiate the Gulf of Mexico (GOM), where inclement weather coupled with no refueling or resting opportunities can be lethal. However, decisions made when navigating such features and their consequences remain largely unknown due to technological limitations of tracking small animals over large areas. We used automated radio telemetry to track three songbird species (Red-eyed Vireo, Swainson's Thrush, Wood Thrush) from coastal Alabama to the northern Yucatan Peninsula (YP) during fall migration. Detecting songbirds after crossing ∼1,000 km of open water allowed us to examine intrinsic (age, wing length, fat) and extrinsic (weather, date) variables shaping departure decisions, arrival at the YP, and crossing times. Large fat reserves and low humidity, indicative of beneficial synoptic weather patterns, favored southward departure across the Gulf. Individuals detected in the YP departed with large fat reserves and later in the fall with profitable winds, and flight durations (mean = 22.4 h) were positively related to wind profit. Age was not related to departure behavior, arrival, or travel time. However, vireos negotiated the GOM differently than thrushes, including different departure decisions, lower probability of detection in the YP, and longer crossing times. Defense of winter territories by thrushes but not vireos and species-specific foraging habits may explain the divergent migratory behaviors. Fat reserves appear extremely important to departure decisions and arrival in the YP. As habitat along the GOM is degraded, birds may be limited in their ability to acquire fat to cross the Gulf. migration | ecological barrier | Gulf of Mexico | songbirds | weather D uring migration, animals encounter ecological barriers, inhospitable environmental features that prevent or impede movement due to increased risk of mortality from starvation, predation, collision, and severe environmental conditions (e.g., weather for aerial migrants, aquatic temperature or chemical gradients for aquatic migrants) (1-5). Because barriers can have important consequences on survival and future reproductive success (6), animals have evolved behavioral, morphological, and/or physiological means to safely negotiate them (7-9). Barriers can include large geographic features (e.g., large water bodies, deserts, mountains), inhospitable land cover types (e.g., agricultural "deserts"), anthropogenic structures (e.g., tall buildings, towers, dams, weirs), and unfavorable weather and aquatic conditions (e.g., droughts, storms, strong temperature gradients), although the extent to which any of these functions as a barrier to migration varies (4,5,(10)(11)(12).Approximately two thirds of all songbird species and millions of individuals breeding in eastern Canada and the United States encounter the Gulf of Mexico (GOM) while migrating to tropical or subtropical wintering grounds in the Caribbean, Mexico, and Central and South America (13). Unfavorable weather conditions combine...

Conspecific attraction, the tendency for individuals of a species to settle near one another, is well described in colonial species, especially birds. Although this behavior may occur in territorial birds, evidence has been lacking. If territorial birds do exhibit this behavior, it would have major conservation implications. Birds could potentially be attracted to specific sites with artificial stimuli, making conservation of those species more efficient. In 2001 and 2002, we tested whether conspecific attraction occurs in an endangered, territorial songbird, the Black-capped Vireo (Vireo atricapilla) by playing vireo vocalizations in unoccupied habitats at Fort Hood, Texas. We were successful in attracting 73 birds to five experimental sites in 2001 and 75 birds to seven experimental sites in 2002. No birds settled on comparable control sites. Many birds attracted to the vocalizations paired and bred. At most research sites the primary threat to the species, the brood-parasitic Brown-headed Cowbird (Molothrus ater), was controlled, allowing vireos to achieve high nesting success relative to a nearby, unmanipulated population. Second-year birds were more responsive to conspecific vocalizations than older birds, as they were more common on experimental sites than in the established population. In 2002 birds recolonized experimental sites from 2001 where vocalizations were not played in 2002, indicating that 1 year of playbacks may be sufficient to establish a population. Our results provide the first experimental evidence that territorial songbirds use the presence of conspecifics when deciding where to settle and suggest that conspecific attraction may provide a valuable conservation tool. Resumen: La atracción conespecífica, tendencia de los individuos de una especie a establecerse cerca de otro de la misma especie, está bien descrita en especies coloniales, especialmente aves. Aunque este comportamiento puede ocurrir en aves territoriales, se carece de evidencia. Si aves territoriales muestran este comportamiento, tendría implicaciones mayores en la conservación. Las aves potencialmente serían atraídas a sitios específicos mediante estímulos artificiales, haciendo más eficiente la conservación de esas especies. En 2001 y 2002, probamos si ocurre la atracción conespecífica en una especie de ave canora territorial, en peligro, Vireo atricapilla, con la reproducción de vocalizaciones de vireo en hábitats desocupados en Fort Hood, Texas. Tuvimoś exito al atraer a 73 aves a cinco sitios experimentales en 2001 y 75 aves a siete sitios experimentales en 2002. No se establecieron aves en sitios controles comparables. Muchas de las aves atraídas a las vocalizaciones formaron pareja y se reprodujeron. En la mayoría de los sitios, la principal amenaza para la especie, el parásito Molothrus ater, fue controlada, lo que permitió un elevadoéxito de anidación a los vireos en comparación con una población no manipulada cercana. Las aves de dos años tuvieron mayor respuesta a las vocalizaciones conespecíficas que las aves más v...

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Numerous studies have confirmed that when selecting habitat birds can use social information acquired from observing other individuals, and many aspects of this social information can be capitalized upon to manage bird populations. The conservation implications of attraction to conspecifics are especially promising for management, and as research progresses it is important to consider how this behavior can be applied to conservation practice. The biological underpinnings of conspecific attraction and the repercussions of manipulating species' distributions with attraction methods are not well understood, but conservation decisions often cannot wait for scientific research. Here we synthesize the current research on manipulation of songbirds by conspecific-attraction methods and review our knowledge gaps critically. We reviewed the published literature on conspecific-attraction experiments in songbirds and found that of 24 studies in which they were attempted, 20 were successful in attracting birds. Although many experiments have been successful in attracting conspecifics with various cues, we outline issues to be considered before songbirds are manipulated by attraction methods, and we highlight areas of research necessary to enhance the understanding of conspecific attraction and its use in conservation.Resumen. Se ha confirmado mediante numerosos estudios que las aves pueden utilizar información social adquirida mediante la observación de otros individuos al seleccionar el hábitat y muchos aspectos de esta información social pueden emplearse para manejar las poblaciones de aves. Las implicaciones de la atracción entre individuos coespecíficos para la conservación son especialmente promisorias para el manejo y a medida que la investigación progresa es importante considerar cómo se puede aplicar este comportamiento a la conservación en la práctica. Las bases biológicas de la atracción entre individuos coespecíficos y las repercusiones de manipular la distribución de las especies mediante métodos de atracción no se entienden adecuadamente, pero las decisiones de conservación a menudo no pueden esperar al desarrollo de investigaciones científicas. En este trabajo, sintetizamos la investigación actual sobre la manipulación de aves canoras mediante métodos de atracción de individuos coespecíficos y revisamos nuestros baches en el conocimiento de forma crítica. Revisamos la literatura publicada sobre experimentos de atracción de individuos coespecíficos en aves canoras y encontramos que, de 24 estudios en los que éstos fueron emprendidos, 20 tuvieron éxito atrayendo a las aves. Aunque muchos experimentos han tenido éxito atrayendo individuos coespecíficos usando varias señales, esbozamos algunos asuntos que deben considerarse antes de manipular a las aves canoras mediante métodos de atracción. Además, resaltamos áreas en las que es necesario realizar investigaciones para mejorar el entendimiento de la atracción de individuos coespecíficos y su uso en conservación.