An examination of factors influencing black fertility decline in the Mississippi Delta, 1880–1930

Abstract

Although the fertility decline in the black population in the Mississippi Delta between the late 1870's and early 1930's closely paralleled that of the national black population, it rose much more dramatically in the 1940's and 1950's to almost 1880 levels. Given the especially rural and oppressed conditions of blacks there, the initial decline seems puzzling. Low fertility rates in the 1930's reflected a large proportion of childless females. Investigations of changing contraceptive usage and mate exposure suggest both were minor components at most. Several physiological impairments were investigated including dietary deficiences, malaria, tuberculosis, and sexually transmitted diseases (STD). Evidence suggests STD played the major role, facilitated by nutritional and other health problems. Models relying heavily on those developed by McFalls and McFalls (1984) suggest 50–80 percent of the decline could have been due to the spread of STD. Age‐specific birth rates for different periods and post‐World‐War‐II fertility increases seem consistent with this finding.     

Those ubiquitous fertility trends: United States, 1945-1979

1970-79 US fertility trends among differnet racial, regional, age, educational, parity, and socioeconomic subgroups in the population were examined, using own children data from the 1976 Survey of Income and Education (SIE) and the March Current Population Surveys (CPS) from 1968-80. In addition, cross-sectional differences in fertility for the subgroups were compared for 1970 and 1976, using multiple regression analysis. 1st, the appropriateness of using fertility rates obtained from own children data was assessed by comparing fertility rates obtained from the SIE data with those derived from vital statistic and census data. The comparative analysis confirmed that the SIE data yielded an accurate estimate of period fertility rates for currently married women, provided the subgroup samples were sufficiently large. CPS fertility estimates were also judged to be accurate if data from 3 adjacent survey years was pooled to increase sample size. Fertility trends for 5 educational groups were assessed separately for 1967-73. During this periold, there was a marked decline in fertility for all 5 groups; for the group with 5-8 years of education the decline was only 14%, but for the other 4 groups, which included women with 9-16 or more years of education, the decline in fertility ranged from 26-29%. In assessing the 1970-76 trends, the sample was restricted to own children, aged 3 years or less, of currently married women, under 40 years of age. Among whites, there was an overall 20% decline in fertility between 1970-76 and an overall fertility increase of about 2% between 1976-79. These trends were observed in all 28 white subgroups. A similar pattern was observed for blacks. There was an overall fertility decline of 24% between 1970-76, and this decline was apparent for all subgroups except women with college degrees. Betwen 1976-79, black fertility rates, unlike white rates, continued to decline, but the rate of decline was only 3%. Furthermore, the decline in almost all the black subgroups was markedly less than in the 1970-76 periold, and for many of the subgroups the trend was reversed and fertility increased. In summary, the fertility trends noted for 1970-79 were pervasive for almost all the subgroups for both blacks and whites; i.e., there was a marked decline in fertility between 1970-76 and than a reversal or slowing down of the decline during the 1976-79 for all black and white subgroups. Cross-sectional fertility differences in the subgroups in 1970 and in 1979 were quite similar, and fertility rates differed markedly for the separate subgroups. These differences do not, of course, explain the pervasive trends observed in the analysis of the fertility rates over time. A similar study assessing fertility trends among subgroups for the early 1940's through the late 1960s also revealed the pervasive nature of period fertility trends. Demographers have not as yet been able to explain these shifts in fertility that cut across all subgroups in the US and which also characterize the period fertility rates in other developed countries. Tables provided information on 1) total fertility rates by educational level and by geographical region for 1945-1975; 2) % change in number of own children less than 3 years of age among women under age 40 by maternal age, maternal education, initial parity, geographical region, and husband's income; and 3) mean number of own children less than 3 years of age among women under age 40 by maternal age, education, parity, region, and husband's income.     

Social,biological, and political considerations on fertility in Arab populations

In analyzing fertility in the Arab countries, crude birth rate, total fecundity rate, and age specific fertility rates were measured. The data was obtained from United Nations, UNICEF, and the World Bank. In the early 1980's 13 of the countries had birth rates 40/1000. The majority of countries showed a decline in their crude birth rate (CBR) between 1960-83, except Somalia, which increased. The United Arab Emirates (UAE), Tunisia, Lebanon, and Kuwait, had the largest CBR decreases, followed by Morocco, Egypt, and Saudi Arabia. The global fecundity rate (GFR) shows the number of expected births a woman lives through her reproductive period, having children at the prevailing rate for each age. The GFR in these countries is much higher than those of non Moslem countries in the area. Results show that the fertility of Arab countries are in a gradual decline, but remain high, and many have a CBR over 40/1000. In the last 20 years Saudi Arabia, with the largest population of oil producing countries, has had a decreasing CBR. It is not in agreement with its high GFR, but this can be attributed to the large number of immigration workers in the country. The UAE showed a decrease in CBR from 46/1000 to 27/1000, the largest decrease in these countries. This decline coincided with the economic development due to oil production. Kuwait had a 25.5% decrease in CBR but less than Tunisia and Lebanon. The fertility decline in Kuwait intensified in the middle 1970's; the decline in northern Africa began in the late 1960's. There were declines in birth rates in the North African countries in the early 1970's except for Tunisia. The rapid declines in fertility can be attributed to the countries' socioeconomic and political situations.     

Demographics of Black Vultures in North Carolina

Abstract: Understanding the contributions of vital rates to species population growth is critical to developing new management protocols. We constructed a model population for black vultures (Coragyps atratus) in North Carolina, USA, based on demographic data from a 14-year study. The model population was similar in stage structure to the reference population, and adult survival was the primary contributor to the annual rate of increase (10.6%). We suggest that the North Carolina black vulture population is experiencing high rates of survival and fertility, potentially breeding at an age younger than previously assumed, and growing rapidly.     

Bear historical ranges revisited: Documenting the increase of a once-extirpated population in Nevada

Black bears (Ursus americanus) were once abundant in Nevada and distributed throughout the state, yet recognition of the species' historical occurrence in the state is uncommon and has therefore been ignored in published distribution maps for North America. The lack of representation on distribution maps is likely due to the lack of any scientific data or research on bears in Nevada until 1987. Historical records dating back to the 1840s compiled by Nevada Department of Wildlife (NDOW) biologist Robert McQuivey indicate presence of black bears throughout the state in the 1800s through about 1930. The paucity of historical references after 1931 suggest extirpation of black bears from Nevada's interior mountain ranges by this time. We report on historical records of black bears in the state of Nevada and the results of a current population estimate of black bears derived from a sample of marked bears (n = 420) captured 707 times between 1997 and 2008. Using Pradel and Cormack–Jolly–Seber models in Program MARK, we estimated overall population size, finite rate of growth (λ = 1.16), quarterly and annual survival rates for males and females, seasonal capture probabilities, and recruitment rates. Our results indicate an overall population size of 262 ± 31 adult black bears in western Nevada. These results suggest that the once abundant, then extirpated population of black bears in Nevada is increasing at an annual average rate of 16%. Although the current distribution is limited to the western part of the state, our findings suggest possible expansion of the population into historical habitat within the interior and eastern portions of the state that have been absent of bears for >80 years. Finally, based on historical records, we present suggested revised historical distribution maps for black bears that include the Great Basin ranges in Nevada. © 2013 The Wildlife Society.     

Forecasting age-related changes in breast cancer mortality among white and black US women: a functional data approach

Background: The disparity in breast cancer mortality rates among white and black US women is widening, with higher mortality rates among black women. We apply functional time series models on age-specific breast cancer mortality rates for each group of women, and forecast their mortality curves using exponential smoothing state-space models with damping. Materials and Methods: The data were obtained from the Surveillance, Epidemiology and End Results (SEER) program of the US [1]. Mortality data were obtained from the National Centre for Health Statistics (NCHS) available on the SEER*Stat database. We use annual unadjusted breast cancer mortality rates from 1969 to 2004 in 5-year age groups (45–49, 50–54, 55–59, 60–64, 65–69, 70–74, 75–79, 80–84). Age-specific mortality curves were obtained using nonparametric smoothing methods. The curves are then decomposed using functional principal components and we fit functional time series models with four basis functions for each population separately. The curves from each population are forecast and prediction intervals are calculated. Results: Twenty-year forecasts indicate an overall decline in future breast cancer mortality rates for both groups of women. This decline appears to be steeper among white women aged 55–73 and black women aged 60–84. For black women under 55 years of age, the forecast rates are relatively stable indicating there is no significant change in future breast cancer mortality rates among young black women in the next 20 years. Conclusion: White women have smooth and consistent patterns in breast cancer mortality rates for all age-groups whereas the mortality rates for black women are much more variable. The projections suggest, for some age groups, black American women may not benefit equally from the overall decline in breast cancer mortality in the United States.     

Variation of natural reproduction parameters and Crow’s indices in different ethnic groups in the two largest megacities of Russia

Genetic-demographic parameters of natural reproduction in the most numerous ethnic groups of Moscow and St. Petersburg were assessed on the basis of the 2002 All-Russia Population Census data and other sources. The intensity of intragroup selection due to individual differences in fertility in the cohorts of women born in the 1930s–1950s decreased in all ethnic groups studied. It was concluded that, in both megacities, the relaxation of the selection component due to differential fertility almost stopped: the values of the Crow’s index I_f stabilized at 0.3 < I_f < 0.4, which was associated with relative stabilization of the interfamily variance of fertility. The temporal dynamics of the intensity of intergroup selection due to interethnic differences in fertility rates was more complex. It was only recently that this type of selection came into action, since even at the beginning of the 20th century fertility rates in various ethno-territorial and ethno-confessional groups of the population of the Russian Empire were similar (5–6 offspring per marriage). In the subsequent decades, interethnic differentiation in progeny size increased because the reproductive behavior of different population groups underwent “modernization” with uneven speed. In Moscow and St. Petersburg, the intensity of intergroup selection decreased in women birth cohorts of the 1930s–1950s, while it was an order of magnitude lower than the intragroup selection. Currently, the average number of offspring varies among ethnic groups in a narrow range from 1.3 to 1.6. It can be expected that interethnic differences in fertility rates in these megacities will increase again owing to growing numbers of migrants from regions with traditionally high birth rates, resulting in differential natural growth of ethnic groups and the corresponding dynamics of the gene pool of the population.     

The ecological history of a mediaeval man-made lake. Hickling Broad,Norfolk, United Kingdom

Changes in Hickling Broad, since its creation in the 14th or 15th centuries by the flooding of peat diggings, have been deduced from dating and analysis of a sediment core, historical information and current limnological studies. Until the 1930's there was little major change. Increased agricultural land fertilization led to markedly increased organic sedimentation from the 1930's onwards, due to increased growth of submerged macrophytes. Inorganic sedimentation increased concurrently as more powerful pumps were installed to help drain the adjacent fens and marshes.There was no evidence of increased plankton populations during this phase, but epiphytic diatom populations increased. In the mid 1960's the current period of hypereutrophication began. Epiphytic diatom numbers increased markedly and in the early 1970's the previous luxuriant macrophytes became sparse and the water became turbid with phytoplankton. These changes are attributable mainly to increases in the size of a roost of migratory black headed gulls (Larus ridibundus L.) on the lake in autumn and winter.     

Gonococcal infection and human fertility in sub-Saharan Africa.

An analysis is presented of the influence of Neisseria gonorrhoeae on human population growth in regions of sub-Saharan Africa where gonococcal infections are prevalent in sexually active adults. Combining epidemiological and demographic data within the framework of a mathematical model, we show that gonorrhoea has a major impact on fertility and, concomitantly, on net population growth in areas with a high prevalence of untreated infections. Specifically, a 20% prevalence in sexually active adults is predicted to induce a 50% reduction in net population growth. Model predictions are in good agreement with observed data from Uganda, and the sensitivity of the prediction to various complications, such as heterogeneity in sexual behaviour, is assessed. The analysis suggests that the predicted increase in fertility arising from expanded sexually transmitted disease (STD) control programmes in Africa to help combat the spread of human immunodeficiency viruses (HIV-1 and HIV-2) will help to offset the predicted demographic impact of AIDS in the worst afflicted areas. In other areas the rise in fertility associated with effective STD control will need to be countered by the linkage of STD control programmes with family planning initiatives.     

Causes of the eelgrass wasting disease: Van der Werff's changing theories

The 1930's wasting disease among the North Atlantic population of eelgrass,Zostera marina, is still an ecological and historical enigma, despite several attractive theories. Van der Werff investigated the die-back of eelgrass in the thirties in the Dutch Wadden Sea, and he considered the micro-organismLabyrinthula as the possible cause of the disease. In 1980, Grevelingen lagoon, harbouring an extensive population ofZostera marina, experienced a major decline of the area covered by the submerged macrophyte. Speculations about the cause of this dramatic decline induced us to think that the wasting disease had struck again. Van der Werff investigated the Grevelingen population and found bothLabyrinthula and a Chaetophoracean endophytic alga to be presumably responsible for the decline. During the quest for the ultimate cause of the wasting disease the question remains whether both micro-organisms are the cause of the disease or simply an effect of decomposition processes triggered by other factors.     

Current Demographics Suggest Future Energy Supplies Will Be Inadequate to Slow Human Population Growth

Influential demographic projections suggest that the global human population will stabilize at about 9–10 billion people by mid-century. These projections rest on two fundamental assumptions. The first is that the energy needed to fuel development and the associated decline in fertility will keep pace with energy demand far into the future. The second is that the demographic transition is irreversible such that once countries start down the path to lower fertility they cannot reverse to higher fertility. Both of these assumptions are problematic and may have an effect on population projections. Here we examine these assumptions explicitly. Specifically, given the theoretical and empirical relation between energy-use and population growth rates, we ask how the availability of energy is likely to affect population growth through 2050. Using a cross-country data set, we show that human population growth rates are negatively related to per-capita energy consumption, with zero growth occurring at ∼13 kW, suggesting that the global human population will stop growing only if individuals have access to this amount of power. Further, we find that current projected future energy supply rates are far below the supply needed to fuel a global demographic transition to zero growth, suggesting that the predicted leveling-off of the global population by mid-century is unlikely to occur, in the absence of a transition to an alternative energy source. Direct consideration of the energetic constraints underlying the demographic transition results in a qualitatively different population projection than produced when the energetic constraints are ignored. We suggest that energetic constraints be incorporated into future population projections.     

Period and cohort dynamics in fertility norms at the onset of the demographic transition in Kenya 1978-1998

A characteristic of African pre-transitional fertility regimes is large ideal family size. This has been used to support claims of cultural entrenchment of high fertility. Yet in Kenya fertility rates have fallen. In this paper this fall is explored in relation to trends in fertility norms and attitudes using four sequential cross-sectional surveys spanning the fertility transition in Kenya (1978, 1984, 1989 and 1998). The most rapid fall in the reported ideal family size occurred between 1984 and 1989, whilst the most rapid fall in the total fertility rate occurred 5 to 10 years later, between 1989 and 1998. Thus these data, spanning the fertility transition in Kenya, support the traditional demographic model that demand for fertility limitation drives fertility decline. These data also suggest that the decline in fertility norms over time was partly a period effect, as the reported ideal family size was seen to fall simultaneously in all age cohorts, and partly a cohort effect, as older age cohorts reporting higher ideal family sizes were replaced by younger cohorts reporting lower ideal family sizes. These data also suggest that a new fertility norm of four children may have developed by 1989 and continued until 1998. This is consistent with, and perhaps could have been used to predict, the stall in the Kenyan fertility decline after 1998.     

Inbreeding effects on fertility in humans: evidence for reproductive compensation.

The effects of inbreeding on prereproductive mortality have been demonstrated in many natural populations, including humans. However, little is known about the effects in inbred individuals who survive to adulthood. We have investigated the effects of inbreeding on fertility among inbred adult Hutterites and demonstrate significantly reduced fecundity among the most inbred Hutterite women, as evidenced by longer interbirth intervals (P=.024) and longer intervals to a recognized pregnancy (P=.010) but not by increased rates of fetal loss (P>.50). These data suggest the presence of recessive alleles that adversely affect fecundity among the population. In contrast, completed family sizes do not differ among the more and the less-inbred Hutterite women who were born after 1920, suggesting that reproductive compensation is occurring among the more-inbred and less-fecund women. This recent reproductive strategy would facilitate the maintenance of recessive alleles and contribute to an overall decline in fertility in the population.     

Canadian fertility trends in perspective

This paper examines the broad movements of Canadian period and cohort fertility over the past 100 years, and compares them with corresponding trends in the US and other industrialized countries. The main movement in Canada was a decline in fertility extending from the 19th century to the present, interrupted in the 1940s and 1950s by a baby boom. Between 1871 and 1937 the total fertility rate (TFR) fell at about an average of 1.4% annually. The rate of fall in the US was similar, with the result that in the late 1930s the Canadian TFR was about 20% that of the US. The fertility boom that followed was steeper in the US than in Canada, and in the downswing that later followed, the rate of decline was similar in the 2 countries (3.4-4% annual average). But, the decline continued longer-- indeed still continues--in Canada, whereas the TFR in the US reached its lowest point in 1976. Moreover, the recent decline in fertility has been more severe in Canada than in almost any other industrialized country. The TFR relates to fertility in a single year and is highly sensitive to short-term changes in the timing of births. For the purposes of understanding and explaining long-term trends in fertility, the completed fertility rate (CFR) is a better index because it measures the ultimate family size of cohorts. Cohort fertility can be seen to fluctuate much less than does period fertility. In both the US and Canada, the peak cohorts, born in the early 1930s, had roughly the same completed fertility, and later cohorts continued to remain closely in step as the CFR fell sharply. In Canada the fall continues, though at a reduced rate, in the latest cohorts for which there is information. Apart from differences in amplitude, the dates of turning points and the shapes of the TFR and CFR curves of Canadian fertility are fairly similar. The long decline in cohort fertility is largely explained by the decrease in the proportions of families of 6 or more children. During the baby boom, for Catholics and non-Catholics alike, the proportion of ever-married women remaining childless fell by about 40%, the proportion having 2 children changed little, and the proportions having 3,4 and 5 children tended to increase substantially. The crucial difference between the 2 groups was in the proportions of women having 6 or more children. For non-Catholics, the proportion fell by over 4% from a high level. For non-Catholics, on the other hand, the proportion rose somewhat, though even after the rise, it was barely more than 1/2 the level to which the Catholic proportion had declined. Among Catholics, the effect of the massive decline in the proportion of women having 6 or more children was to swamp the effects of the increase in the proportions of women having 3, 4 and 5 children. The net effect was that fertility declined. Among non-Catholics, however, the comparable increases in the proportions of families of 3, 4 and 5 children, were not offset by any fall in the proportion of larger families, with the result that a baby boom occurred.     

Bevölkerungswachstum: Bildung ist die Lösung

Population growth – education is the answer Over the last decades world population has been constantly growing by some 80 million per year. Whereas the growth rate as well as the fertility rate have been cut by half since the 1970th, population growth will continue well over mid‐century. As the developed countries have completed the demographic transition from high mortality and fertility rates to low ones, population growth is fading out there or has already been reversed into decline. In the least developed countries mortality has fallen as well, whereas fertility decline has stalled. Therefor population growth is very high making the solution of the widespread problems in this part of the world more and more difficult. One obvious way out of this trap would be a better education that could open new development perspectives. A positive side effect is that educated women have much less offspring than their counterparts who never went to school.     

Recent trends and components of change in fertility in Nepal

The objectives of this article are, first, to provide improved estimates of recent fertility levels and trends in Nepal and, second, to analyse the components of fertility change. The analysis is based on data from Nepal's 1996 and 2001 Demographic and Health Surveys. Total fertility rates (TFR) are derived by the own-children method. They incorporate additional adjustments to compensate for displacement of births, and they are compared with estimates derived by the birth-history method. Fertility is estimated not only for the whole country but also by urban/rural residence and by woman's education. The own-children estimates for the whole country indicate that the TFR declined from 4.96 to 4.69 births per woman between the 3-year period preceding the 1996 survey and the 3-year period preceding the 2001 survey. About three-quarters of the decline stems from reductions in age-specific marital fertility rates and about one-quarter from changes in age-specific proportions currently married. Further decomposition of the decline in marital fertility, as measured by births per currently married woman during the 5-year period before each survey, indicates that almost half of the decline in marital fertility is accounted for by changes in population composition by ecological region, development region, urban/rural residence, education, age at first cohabitation with husband, time elapsed since first cohabitation, number of living children at the start of the 5-year period and media exposure. With these variables controlled, another one-third of the decline is accounted for by increase in the proportion sterilized at the start of the 5-year period before each survey.     

Changes in sibling configurations for American preschool children.

This paper uses data drawn from the 1940 through 1980 Public Use Microdata Samples of the U.S. Census of Population to document sibling configurations from the child's perspective. Changes in four aspects of siblings are examined for five cohorts of white and black preschool-aged children: number, birth order distributions, spacing intervals, and sex composition. Changes in fertility behavior of adults in the post-war era had a profound effect on the structure of sibling systems experienced by children. Successive cohorts of preschool children show a rise in number of siblings through the early post-war years before showing sharp declines in number of siblings through the 1960's and 1970's. These shifts in size of sibling sets are reflected in changes in the proportion of each cohorts who are first born and only children, both of which have increased substantially by the 1980 cohort. The 1940 and 1980 cohorts have similar proportions of children with short intervals. However, the middle cohorts show the effects of the quickened pace of fertility with substantial proportions of children with comparatively short birth intervals. Finally, substantial shifts across cohorts in several measures of sex composition of children are observed. Most significantly, there is a marked decline in the proportion of children experiencing an opposite-sex older sibling.     

Demography and evolution of an urban ethnic community: Polish Hill, Pittsburgh.

Polish Hill is an urban, ethnic enclave of approximately 3000 residents residing in a 25-block area of Pittsburgh. This paper documents changes in the fertility, morbidity, and mortality patterns in the community from the turn of the century to the present. The demographic reconstruction is based upon baptismal and marriage records, the administration of demographic proformae and population censuses. The high mortality, morbidity, and fertility variance suggest that the immigrant population has experienced a period of high opportunity for selection in the early 1900's and that Crow's index was gradually reduced to its present level.     

Effect of famine on fertility in a rural area of Bangladesh

Data on household socioeconomic status collected in the 1974 census and registration data on births, deaths, and migrations for the 1974-77 period from the Demographic Surveillance System of the International Centre for Diarrheal Disease Research, Bangladesh, were used to investigate the effects of the 1974-75 famine on differential fertility in a rural population of Bangladesh. Occupation of household head was used as a measure of socioeconomic status. Overall, fertility declined by 34% over the 1975-76 period and increased by 17% in 1976-77 from the 1974-75 figure. Significantly lower fertility was observed in 1975-76, irrespective of socioeconomic status, but the lower socioeconomic groups were affected more than the higher groups. Post-famine fertility was significantly higher only in the 2 middle occupation categories. The age-specific fertility rates suggest that the famine affected all age groups. The post-famine fertility was higher than that of 1974-75 in all but those aged below 20. At age 40 and over the recovery was slight. Husband-wife separation showed an increase during the famine and particularly among the lower socioeconomic groups. The males of the lower socioeconomic households migrated to other regions to obtain food for the family, thus affecting frequency of coitus. The decline in fertility may be due to several factors: deferred marriage; increase in divorces and husband-wife separations; high fetal wastage; voluntary fertility control through contraception, abstention, or induced abortion; and infecundability. An indirect measure of marriage rate indicated that fewer couples entered into marriage in 1974-75, particularly in the lower socioeconomic groups. Both the higher and lower socioeconomic groups were affected by the famine but the precise mechanisms were not the same. At this stage, it is not feasible to estimate the contribution of each factor to the fertility decline. The lower socioeconomic groups were more affected by husband-wife separations and deferred marriages; the higher socioeconomic groups were affected by mental stress and anxiety.     

Predation on an upper trophic marine predator, the Steller sea lion: evaluating high juvenile mortality in a density dependent conceptual framework

The endangered western stock of the Steller sea lion (Eumetopias jubatus)--the largest of the eared seals--has declined by 80% from population levels encountered four decades ago. Current overall trends from the Gulf of Alaska to the Aleutian Islands appear neutral with strong regional heterogeneities. A published inferential model has been used to hypothesize a continuous decline in natality and depressed juvenile survival during the height of the decline in the mid-late 1980's, followed by the recent recovery of juvenile survival to pre-decline rates. However, these hypotheses have not been tested by direct means, and causes underlying past and present population trajectories remain unresolved and controversial. We determined post-weaning juvenile survival and causes of mortality using data received post-mortem via satellite from telemetry transmitters implanted into 36 juvenile Steller sea lions from 2005 through 2011. Data show high post-weaning mortality by predation in the eastern Gulf of Alaska region. To evaluate the impact of such high levels of predation, we developed a conceptual framework to integrate density dependent with density independent effects on vital rates and population trajectories. Our data and model do not support the hypothesized recent recovery of juvenile survival rates and reduced natality. Instead, our data demonstrate continued low juvenile survival in the Prince William Sound and Kenai Fjords region of the Gulf of Alaska. Our results on contemporary predation rates combined with the density dependent conceptual framework suggest predation on juvenile sea lions as the largest impediment to recovery of the species in the eastern Gulf of Alaska region. The framework also highlights the necessity for demographic models based on age-structured census data to incorporate the differential impact of predation on multiple vital rates.