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Mortality Decline (mortality + decline)
Selected AbstractsVehicles versus conservation of invertebrates on sandy beaches: mortalities inflicted by off-road vehicles on ghost crabsMARINE ECOLOGY, Issue 3 2007Thomas A. Schlacher Abstract Sandy beaches face increasing anthropogenic pressures, with vehicle traffic being ecologically highly harmful. Ghost crabs (Fam. Ocypodidae) are conspicuous on many beaches, and they have been used as a bio-monitoring tool to measure the ecological responses to human disturbance. However, the mechanisms causing declines in crab numbers are unknown, yet conservation must target the actual impact mechanisms. Therefore, we quantified the magnitude and mechanisms of off-road vehicle (ORV) impacts on ghost crabs, addressing three key questions: (i) Does abundance of ghost crabs respond to traffic intensity?; (ii) Can burrows protect crabs from vehicles? and (iii) Can mortalities caused by vehicles contribute to population declines? ORV-impacts were measured on North Stradbroke Island (Australia) for Ocypode cordimanus and Ocypode ceratophthalma. Crab densities were significantly lower in areas subjected to heavy beach traffic, suggesting direct crushing by vehicles. Burrows only partially protect crabs against cars: all individuals buried shallow (5 cm) are killed by 10 vehicle passes. Mortality declines with depth of burrows, but remains considerable (10,30% killed) at 20 cm and only those crabs buried at least 30 cm are not killed by ORVs: these ,deep-living' crabs represent about half of the population. After crabs emerge at dusk they are killed in large numbers on the beach surface. A single vehicle can crush up to 0.75% of the intertidal population. While conservation measures should primarily regulate night traffic, our results also emphasise that the fossorial life habits of sandy beach animals cannot off-set the impacts caused by ORVs. [source] Safe motherhood in Jamaica: from slavery to self-determinationPAEDIATRIC & PERINATAL EPIDEMIOLOGY, Issue 4 2005Affette McCaw-Binns Summary The development of maternal health care in Jamaica is reviewed by examining government documents and publications to identify social and political factors associated with maternal mortality decline. Modern maternity services began with the 1887 establishment of the Victoria Jubilee Hospital and Midwifery School. Community midwives were deployed widely by the 1930s and community antenatal care expanded in the 1950s. Social policies in the 1970s increased women's access to primary health care, education and social support; improved transportation in the 1990s facilitated hospital delivery. Maternal mortality declined rapidly from ,600/100 000 in the 1930s to 200/100 000 in 1960, led by a 69% decline in sepsis by 1950, and a 72% decline from all causes thereafter, settling at ,100/100 000 in the 1980s. Skilled birth attendant deliveries moved from 39% in 1950 to 95% in 2001 and hospital births from 31% in 1960 to 91% in 2001. Maternal mortality plateaued at 70,80% prevalence of skilled delivery care. Deployment of midwives into rural communities and social development focused on women and children were associated with the observed improvements. Further reductions will require greater attention to the quality of emergency obstetric care. [source] Rethinking Historical Reproductive Change: Insights from Longitudinal Data for a Spanish TownPOPULATION AND DEVELOPMENT REVIEW, Issue 4 2007David Sven Reher A set of linked reproductive histories taken from the Spanish town of Aranjuez between 1871 and 1950 is used to address key issues regarding reproductive change during the demographic transition. These include the role of child survival as a stimulus for reproductive change, the use of stopping and/or spacing strategies to achieve reproductive goals, and the timing of change. Straightforward demographic measures are used and robust results are achieved. Initial strategies of fertility limitation are shown to exist but are inefficient, are mostly visible during the latter part of the reproductive period, are designed mostly to protect families from the effects of increases in child survival, and are based almost entirely on stopping behavior. As mortality decline accelerates, strategies become much more efficient, are visible at the outset of married life, include spacing behavior, and eventually lead to important declines in completed family size. The results of this study have implications for our understanding of the demographic transition both in historical Europe and in other regions of the world. [source] Reassessing the Insurance Effect: A Qualitative Analysis of Fertility Behavior in Senegal and ZimbabwePOPULATION AND DEVELOPMENT REVIEW, Issue 3 2003Thomas LeGrand A number of prominent demographers have recently reiterated the argument that a lasting mortality decline is a key determinant of the fertility transition. Of the main hypothesized pathways linking fertility to mortality, the one least studied is the insurance hypothesis: the notion that, in high-mortality contexts, people decide to have more children in order to anticipate possible future child deaths and lessen the risks of having too few surviving offspring. In-depth interviews and focus groups from Zimbabwe and Senegal are used to examine this hypothesis and to extend it into a broader theory of reproductive decision making under uncertainty. Whereas insurance strategies are frequent in Zimbabwe and occur in urban Senegal, in the higher-mortality settings,the rural Senegalese site and the recent past described by respondents in Zimbabwe and urban Senegal,deliberate fertility-limitation strategies are rare. The data depict fundamental changes in attitudes, strategies, and behaviors concerning family size over time and, in Senegal, over space. Important reproductive goals and risks extend far beyond numbers of children and mortality. Parents seek to have healthy, successful children for many reasons including companionship, descendants, and old-age support. Diverse investments in child quality (their education, health, etc.) and quantity (numbers of births) are the main means to attain these goals and, less recognized by demographers, are also important ways for parents to manage uncertainty in family-building outcomes; the "classic" insurance mechanism is only one, often minor, aspect of the quantity option. [source] The demographic transition revisited as a global processPOPULATION, SPACE AND PLACE (PREVIOUSLY:-INT JOURNAL OF POPULATION GEOGRAPHY), Issue 1 2004David S. Reher Abstract With dramatic declines in fertility taking place throughout the world, it is increasingly important to understand the demographic transition as a global process. While this universality was a cornerstone of classic transition theories, for many decades it was largely neglected by experts because fertility in the developing world did not seem to follow the expected pattern. When comparing earlier and more recent transition experiences, important similarities and disparities can be seen. Everywhere mortality decline appears to have played a central role for fertility decline. The differences in the timing of the response of fertility to mortality decline, with very small gaps historically and prolonged ones in more recent transitions, plus the much more rapid decline in vital rates in many developing countries, constitute an important challenge to any general explanation of the process. The specific characteristics of recent transitions have led to decades of higher population growth rates, and promise to give way to much more rapid dynamics of population ageing in many countries. This may limit the ability of newcomers to take full advantage of the demographic transition for the social and economic modernisation of their societies. Copyright © 2004 John Wiley & Sons, Ltd. [source] | ||||||||||