scholarly journals Effects of intrinsic and time-specific factors on daily nest survival of birds in a semiarid area of South America (Caatinga)

2016 ◽  
Vol 24 (3) ◽  
pp. 228-234 ◽  
Author(s):  
Leonardo Fernandes França ◽  
Camila Melo da Silva ◽  
Luciana Vieira de Paiva
2018 ◽  
Vol 59 (2) ◽  
pp. 415-445
Author(s):  
Kathrin Pindl

Abstract This paper is concerned with the storage policy of the citizens’ hospital of Regensburg in the Early Modern period (focus: 18th century). The main purpose consists of (1) a source-based micro-study that helps to derive insights into the mechanisms of how experiences and expectations have influenced decisions by a pre-modern institution, (2) an analytical scheme for describing and evaluating the process of decision-making based on narrative evidence, and (3) the suggestion of analytical categories. These should allow a differentiation between time-invariant human behaviour that determines economic decisions, and time-specific factors which can be used to separate possibly “pre-modern” patterns from seemingly modern-day capitalist economic performance.


The Auk ◽  
2005 ◽  
Vol 122 (2) ◽  
pp. 661 ◽  
Author(s):  
Todd A. Grant ◽  
Terry L. Shaffer ◽  
Elizabeth M. Madden ◽  
Pamela J. Pietz

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Jihen Boukhriss ◽  
Slaheddine Selmi

Abstract Background Investigating the ecological factors and processes shaping nest survival is of great importance for assessing the breeding success of bird populations and understanding their spatio-temporal dynamics. Here, this question is addressed for the Laughing Dove (Spilopelia senegalensis), an expanding Afro-tropical bird in the Tunisian oasis habitat. Methods This study took place in Kettana oasis, in south-eastern Tunisia. Natural Laughing Dove nests were searched for and monitored by means of regular visits, from the discovery date until the end of the breeding attempt (i.e. fledging or failure). Data were then used to investigate the relevance of laying date, nest age (days after clutch initiation), nest height and vegetation structure in the close nest tree environment as predictors of daily nest survival rate, using logistic-exposure models that accounted for heterogeneity in monitoring period among the studied nests. Models including different combinations of covariates were ranked according to their AICc scores, and the model-averaging technique was used for the assessment of the effects of covariates on daily nest survival rate. Results Vegetation structure in the close nest tree environment and nest age provided important predictors of daily nest survival rate, whereas neither nest height nor laying date showed significant effects. Daily nest survival rate was negatively associated with the presence of date palm trees in the close nest tree environment, but it was positively related to nest age. Daily nest survival rate was higher during the post-hatching stage than during the pre-hatching stage. Conclusions Nests placed on fruit trees close to clumps of palm trees suffered higher predation risks compared to those placed on fruit trees situated far from palm trees. This is probably because palm tree clumps provided refuges for nest predators, notably the Black Rat (Rattus rattus) which has been reported to be the main nest predator in the oasis habitat. The predatory activity of this rodent seemed more directed against eggs than nestlings, which may explain the observed increase in daily survival rate with nest age.


The Condor ◽  
2007 ◽  
Vol 109 (2) ◽  
pp. 377-388 ◽  
Author(s):  
Scott Wilson ◽  
Kathy Martin ◽  
Susan J. Hannon

Abstract Nest predation is the most important factor limiting reproductive success of Willow Ptarmigan (Lagopus lagopus), as it is for many bird species. Using program MARK, we examined patterns of daily nest survival in two widely separated populations of Willow Ptarmigan in Manitoba and British Columbia, Canada, by examining variation among years, over the course of the breeding season or in relation to the age of the nest, or age and condition of the female. At La Pérouse Bay, Manitoba, daily nest survival increased linearly throughout the season, with moderate annual variation. Nests also had higher daily survival during laying and late in incubation, and lower survival early in incubation. At Chilkat Pass, British Columbia, daily nest survival varied strongly by year and nests had higher survival early and late in the season, but survival was not affected by the age of the nest. At both sites, but especially at Chilkat Pass, periods of lower nest survival tended to coincide with peak breeding periods, suggesting predators may adjust their search effort based on the likelihood of locating nests. Neither female age nor condition were included in the best models. Thus, in both ptarmigan populations, nest survival patterns appeared to be influenced more by ecological factors than by individual characteristics of breeding females. The extent of annual variation and seasonal patterns may have differed between sites due to the different predator and alternative prey communities.


2005 ◽  
Vol 62 (11) ◽  
pp. 2649-2660 ◽  
Author(s):  
Geoffrey B Steinhart ◽  
Nancy J Leonard ◽  
Roy A Stein ◽  
Elizabeth A Marschall

We studied how storms, angling, and nest predation during angling affected smallmouth bass (Micropterus dolomieu) nest survival in the Bass Islands, Lake Erie, Ohio, USA. Increasing angler effort and introduction of an exotic nest predator, round goby (Neogobious melanostomus), have raised concerns about smallmouth bass recruitment in Lake Erie. We surveyed smallmouth bass nests and calculated daily survival rates for nests assigned to different angling treatments: control, angling without predation, or angling with predation treatments. Only 30% of control nests were successful compared with 11% of angling without predation and 14% of angling with predation treatments. We used the Mayfield method and maximum likelihood models in the program MARK to estimate the survival rates for nests of different treatments and exposed to different numbers of storms. Although nest predators consumed about 35% of broods during angling, daily nest survival rates of both angling treatments were similar. Angling reduced nest survival compared with controls by approximately 5%. Storms reduced both nest success and daily survival. The best model predicting daily nest survival included the added effects of angling treatment and number of storms. Thus, whereas storms and angling affected smallmouth bass nest survival, nest predation during angling did not.


2016 ◽  
Vol 20 (8) ◽  
pp. 1987-2009 ◽  
Author(s):  
Georges Bresson ◽  
Jean-Michel Etienne ◽  
Pierre Mohnen

This paper proposes a Bayesian approach to estimating a factor-augmented GDP per capita equation. We exploit the panel dimension of our data and distinguish between individual-specific and time-specific factors. On the basis of 21 technology, infrastructure, and institutional indicators from 82 countries over a 19-year period (1990 to 2008), we construct summary indicators of each of these three components in the cross-sectional dimension and an overall indicator of all 21 indicators in the time-series dimension and estimate their effects on growth and international differences in GDP per capita. For most countries, more than 50% of GDP per capita is explained by the four common factors we have introduced. Infrastructure is the greatest contributor to total factor productivity, followed by technology and institutions.


The Auk ◽  
2001 ◽  
Vol 118 (4) ◽  
pp. 1018-1028 ◽  
Author(s):  
Amanda D. Rodewald ◽  
Richard H. Yahner ◽  
J. Brawn

AbstractAlthough area and isolation effects on avian communities in highly fragmented landscapes are well known, importance of landscape composition in more forested landscapes remains poorly understood. We determined if the type (agriculture and silviculture) and extent (percentage within 1 km radius) of disturbance within forested landscapes influenced avian nesting success, and then examined if differences in stand-level habitat structure, nest-patch microhabitat, distance of nests to habitat edges, brood parasitism rates, and nest-predator abundance were potential underlying mechanisms of observed associations between landscape composition and nesting success. We monitored active songbird nests (n = 341), surveyed Brown-headed Cowbirds (Molothrus ater) and nest predators, and measured stand-level and nest-patch microhabitat from May–July 1998 and 1999. Each of 10 study sites was located within contiguous mature forest in central Pennsylvania and contained either agricultural or silvicultural disturbances (n = 5 each). Sites of the two landscape types had similar ranges of disturbance within 1 km (21–55% for agriculture, 18–51% for silviculture). Daily nest survival for all species combined (94.0 ± 0.55 in agriculture and 96.9 ± 0.87 in silviculture) and midstory-canopy nesters (93.8 ± 0.97 in agriculture and 97.4 ± 0.75 in silviculture) were greater within forested landscapes disturbed by silviculture than by agriculture, but rates did not significantly differ between landscapes for ground nesters (92.2 ± 1.32 in agriculture and 94.6 ± 1.63 in silviculture) or understory nesters (95.4 ± 1.60 in agriculture and 95.0 ± 1.47 in silviculture). Nest survival was not significantly associated with disturbance extent. Rates of brood parasitism were low, with only 11% of nests containing cowbird eggs or young. Neither nest fate nor differences in daily nest survival between the two landscape types were explained by variation in brood parasitism rates, stand-level or nest-patch habitat characteristics, or distance of nests to edges. Instead, the lower nest success within forested landscapes disturbed by agriculture was best explained by greater abundances of some avian and small mammalian predators (American Crow [Corvus brachyrhynchos] and squirrels) in those landscapes in one or both years. Results suggest that landscape composition within forested landscapes significantly influences avian nesting success by altering interactions between nest predators and nesting birds.


The Condor ◽  
2020 ◽  
Vol 122 (2) ◽  
Author(s):  
Rose J Swift ◽  
Michael J Anteau ◽  
Megan M Ring ◽  
Dustin L Toy ◽  
Mark H Sherfy

Abstract Upon reproductive failure, many bird species make a secondary attempt at nesting (hereafter, “renesting”). Renesting may be an effective strategy to maximize current and lifetime reproductive success, but individuals face uncertainty in the probability of success because reproductive attempts initiated later in the breeding season often have reduced nest, pre-fledging, and post-fledging brood survival. We evaluated renesting propensity, renesting intervals, and renest reproductive success of Piping Plovers (Charadrius melodus) by following 1,922 nests and 1,785 unique breeding adults from 2014 to 2016 in the Northern Great Plains of the United States. The apparent renesting rate for individuals was 25% for reproductive attempts that failed in the nest stage (egg laying and incubation) and only 1.2% for reproductive attempts when broods were lost. Renesting propensity declined if reproductive attempts failed during the brood-rearing stage, nests were depredated, reproductive failure occurred later in the breeding season, or individuals had previously renested that year. Additionally, plovers that nested on reservoirs were less likely to renest compared to other habitats. Renesting intervals declined when individuals had not already renested, were after-second-year adults without known prior breeding experience, and moved short distances between nest attempts. Renesting intervals also decreased if the attempt failed later in the season. Overall, reproductive success and daily nest survival were lower for renests than first nests throughout the breeding season. Furthermore, renests on reservoirs had reduced apparent reproductive success and daily nest survival unless the predicted amount of habitat on reservoirs increased within the breeding season. Our results provide important demographic measures for this threatened species and suggest that predation- and water-management strategies that maximize success of early nests would be more likely to increase productivity. Altogether, renesting appears to be an unproductive reproductive strategy to replace lost reproductive attempts for Piping Plovers breeding in the Northern Great Plains.


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