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Jeffrey M Black - One of the best experts on this subject based on the ideXlab platform.
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black brant Branta bernicla nigricans forage at both tides on humboldt bay california usa
Wildfowl, 2013Co-Authors: Elizabeth Elkinton, Long Lo, Jeffrey M BlackAbstract:Black Brant Branta bernicla nigricans arrive at their breeding grounds in arctic and subarctic North America and eastern Russia in spring, a time when food resources are limited. They rely largely on energy stores, acquired at staging sites, for migration and to support egg laying and incubation. In California, Humboldt Bay is the most important staging site for Black Brant due to the abundance of Common Eelgrass Zostera marina along its shores. Access to Common Eelgrass has been assumed to be limited to low tides, when the plants are reachable, and that little feeding occurs at higher tides. We tested this assumption by quantifying Black Brant foraging behaviour throughout the tidal cycle, including in relation to factors that contribute to the occurrence of detached Common Eelgrass leaves, which float to the surface and thus become available to the birds at higher tides. Throughout the winter and spring periods (January–April 2011) Black Brant at Humboldt Bay foraged directly on Common Eelgrass beds during low tides and continued to feed on drifting leaves during higher tides. They switched from bed-feeding to drift-feeding at a mean tide height of 0.9 m. On average, 48% of flock members typically fed when Common Eelgrass beds were reachable during low tides, with 24% of birds feeding on drifting eelgrass during higher tides. The prevalence of drift-feeding declined as the tide level increased in the bay, ranging from 35% of birds at 1 m tides to 10% at 2.5 m tides. The amount of drifting Common Eelgrass available to Black Brant increased with higher maximum wind speeds and greater tidal range in the previous 24 h, and with greater numbers of Black Brant on the bay. By providing current information about foraging strategies and the use of high-tide feeding opportunities, this study can inform future projections of the carrying capacity of Humboldt Bay for staging Brant. This is particularly important in light of projected future impacts of sea level rises on food availability at staging habitats along the Pacific Flyway.
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Exuberant youth: the example of triumph ceremonies in Barnacle geese (Branta leucopsis)
Ethology Ecology & Evolution, 1995Co-Authors: E. Bigot, Martine Hausberger, Jeffrey M BlackAbstract:A study of a semi-captive Barnacle geese (Branta leucopsis) flock showed clearly that triumph ceremony frequency is related to the age of birds and is highest in young pairs. Females had an active role in that they could encourage or inhibit the male display. Younger females showed more encouraging behaviour than older ones. We argue that triumph ceremonies play a significant part during pair formation and maintenance. Older pairs may need less investment in such displays.
James S Sedinger - One of the best experts on this subject based on the ideXlab platform.
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carryover effects associated with winter location affect fitness social status and population dynamics in a long distance migrant
The American Naturalist, 2011Co-Authors: James S Sedinger, Jason L Schamber, David H Ward, Christopher A Nicolai, Bruce ConantAbstract:AbstractWe used observations of individually marked female black brant geese (Branta bernicla nigricans; brant) at three wintering lagoons on the Pacific coast of Baja California—Laguna San Ignacio (LSI), Laguna Ojo de Liebre (LOL), and Bahia San Quintin (BSQ)—and the Tutakoke River breeding colony in Alaska to assess hypotheses about carryover effects on breeding and distribution of individuals among wintering areas. We estimated transition probabilities from wintering locations to breeding and nonbreeding by using multistratum robust-design capture-mark-recapture models. We also examined the effect of breeding on migration to wintering areas to assess the hypothesis that individuals in family groups occupied higher-quality wintering locations. We used 4,538 unique female brant in our analysis of the relationship between winter location and breeding probability. All competitive models of breeding probability contained additive effects of wintering location and the 1997–1998 El Nino–Southern Oscillation (...
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survival and breeding advantages of larger black brant Branta bernicla nigricans goslings within and among cohort variation
The Auk, 2007Co-Authors: James S Sedinger, Nathan D ChelgrenAbstract:Abstract We examined the relationship between mass late in the first summer and survival and return to the natal breeding colony for 12 cohorts (1986-1997) of female Black Brant (Branta bernicla nigricans). We used Cormack-Jolly-Seber methods and the program MARK to analyze capture-recapture data. Models included two kinds of residuals from regressions of mass on days after peak of hatch when goslings were measured; one based on the entire sample (12 cohorts) and the other based only on individuals in the same cohort. Some models contained date of peak of hatch (a group covariate related to lateness of nesting in that year) and mean cohort residual mass. Finally, models allowed survival to vary among cohorts. The best model of encounter probability included an effect of residual mass on encounter probability and allowed encounter probability to vary among age classes and across years. All competitive models contained an effect of one of the estimates of residual mass; relatively larger goslings survived t...
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early environment and recruitment of black brant Branta bernicla nigricans into the breeding population
The Auk, 2004Co-Authors: James S Sedinger, Mark P Herzog, David H WardAbstract:Abstract In geese, growth regulates survival in the first year. We examined whether early growth, which is primarily governed by environmental conditions, also affects the probability that individuals that survive their first year enter the breeding population. We used logistic regression on a sample of Black Brant (Branta bernicla nigricans) that were weighed at a known age in their first summer and observed during winter (indicating that they had survived the principal mortality period in their first year) to study whether early growth influenced the probability that those individuals would be recruited into the breeding population. We also examined the effects of cohort (1986–1996), sex, age when measured, and area where individuals were reared. The model with the lowest Akaike's Information Criterion score contained body mass, age (days) at measurement, cohort, sex, and brood-rearing area. Models that included variable mass had 85% of the cumulative model weight of the models we considered, indicating...
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natal and breeding philopatry in a black brant Branta bernicla nigricans metapopulation
Ecology, 1998Co-Authors: Mark S Lindberg, James S Sedinger, Dirk V Derksen, Robert F RockwellAbstract:We estimated natal and breeding philopatry and dispersal probabilities for a metapopulation of Black Brant (Branta bernicla nigricans) based on observations of marked birds at six breeding colonies in Alaska, 1986–1994. Both adult females and males exhibited high (>0.90) probability of philopatry to breeding colonies. Probability of natal philopatry was significantly higher for females than males. Natal dispersal of males was recorded between every pair of colonies, whereas natal dispersal of females was observed between only half of the colony pairs. We suggest that female-biased philopatry was the result of timing of pair formation and characteristics of the mating system of brant, rather than factors related to inbreeding avoidance or optimal discrepancy. Probability of natal philopatry of females increased with age but declined with year of banding. Age-related increase in natal philopatry was positively related to higher breeding probability of older females. Declines in natal philopatry with year of banding corresponded negatively to a period of increasing population density; therefore, local population density may influence the probability of nonbreeding and gene flow among colonies.
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environmental influence on life history traits growth survival and fecundity in black brant Branta bernicla
Ecology, 1995Co-Authors: James S Sedinger, Paul L Flint, Mark S LindbergAbstract:We studied relationships between body size of female Black Brant goslings (Branta bernicla nigricans) late in their growth period and first year survival, eventual adult body size, breeding propensity, and size and volume of clutches they eventually produced to examine the relationship between growth and fitness in this population. We indexed body size by calculating PC1 scores based on either culmen and tarsus, or culmen, tarsus, and mass. Gosling (PC scores based on culmen and tarsus) size was positively correlated with resighting rate (P = 0.005), indicating that larger goslings survived at a higher rate than did smaller goslings. Gosling size was correlated with adult size of the same individuals (P = 0.0004). Larger goslings were more likely to breed as 2- or 3-yr-olds than were medium or small goslings (P = 0.008). Larger adult brant laid more eggs (P = 0.03) and produced clutches with greater total volume (P = 0.03) than did smaller brant. Given the important role of foraging environment in growth of goslings, these data suggest an important role of early environment in determining life-history traits.
Lily Montarcih Limantara - One of the best experts on this subject based on the ideXlab platform.
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Optimization of Improvement and Management on Sumber Brantas Watershed, East Java, Indonesia
2020Co-Authors: Lily Montarcih LimantaraAbstract:This paper studied the optimization of improvement and management watershed. Location of study was at Sumber Brantas watershed, Malang-East Java Province Indonesia, with area number was 43,529.25 ha. The methodology consisted of erosion analysis and its conservation, and then to analyze run off and optimized erosion due to optimization of land using. Result was used as consideration to improve and manage Sumber Brantas watershed.
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Evaluation of synthetic rainfall application with respect to the flow volume at upstream Brantas watershed, East Java Province of Indonesia
Journal of Water and Land Development, 2017Co-Authors: Lily Montarcih Limantara, Donny Harisuseno, Rana Karinta HapsariAbstract:Indonesian Technical Implementation Unit (UPT) of Synthetic Rainfall has modified climate by generating synthetic rainfall from 9ᵗʰ May until 4ᵗʰ June 2013. This unit has cooperated with the Department of Technological Study and Application (BPPT) of Indonesia and Perum Jasa Tirta I and TNI AU Lanud Abdulrachman Saleh. This study intended to increase reservoirs water level in upstream Brantas watershed, one of them is Sutami reservoir. Successive grade evaluation of synthetic rainfall used the method of Double Ratio and Flow Discharge. The target area is upstream Brantas watershed that is represented by 12 rainfall stations and the control area is in the distance of ±30 km from the boundary of upstream Brantas watershed and is represented by 5 rainfall stations. Results show rainfall increasing by 152.05% according to the Double Ratio method and the increase of flow discharge from Sutami reservoir by 74.19% according to the Flow Discharge method.
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Conformity evaluation of synthetic unit hydrograph (case study at upstream Brantas sub watershed, East Java Province of Indonesia)
Journal of Water and Land Development, 2017Co-Authors: Dwi Priyantoro, Lily Montarcih LimantaraAbstract:AbstractThis study intends to analyse the suitable hydrograph in upstream Brantas sub watershed. The methodology consists of comparing the result of hydrograph due to the methods of Nakayasu synthetic unit hydrograph (SUH), Limantara synthetic unit hydrograph, and the observed unit hydrograph. In detail, this study intends to know the difference of hydrograph parameters: α and Tg as recommended by Nakayasu and in the study location; to know the influence of main river length which is used in the methods of Nakayasu and Limantara to the time of concentration; to know the hydrograph ordinate deviation between Nakayasu and Limantara due to the observed hydrograph. Result is hoped for recommending the suitable hydrograph in upstream Brantas subwatershed so that it can be used accurately for the further design of water resources structure.
Mark S Lindberg - One of the best experts on this subject based on the ideXlab platform.
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natal and breeding philopatry in a black brant Branta bernicla nigricans metapopulation
Ecology, 1998Co-Authors: Mark S Lindberg, James S Sedinger, Dirk V Derksen, Robert F RockwellAbstract:We estimated natal and breeding philopatry and dispersal probabilities for a metapopulation of Black Brant (Branta bernicla nigricans) based on observations of marked birds at six breeding colonies in Alaska, 1986–1994. Both adult females and males exhibited high (>0.90) probability of philopatry to breeding colonies. Probability of natal philopatry was significantly higher for females than males. Natal dispersal of males was recorded between every pair of colonies, whereas natal dispersal of females was observed between only half of the colony pairs. We suggest that female-biased philopatry was the result of timing of pair formation and characteristics of the mating system of brant, rather than factors related to inbreeding avoidance or optimal discrepancy. Probability of natal philopatry of females increased with age but declined with year of banding. Age-related increase in natal philopatry was positively related to higher breeding probability of older females. Declines in natal philopatry with year of banding corresponded negatively to a period of increasing population density; therefore, local population density may influence the probability of nonbreeding and gene flow among colonies.
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environmental influence on life history traits growth survival and fecundity in black brant Branta bernicla
Ecology, 1995Co-Authors: James S Sedinger, Paul L Flint, Mark S LindbergAbstract:We studied relationships between body size of female Black Brant goslings (Branta bernicla nigricans) late in their growth period and first year survival, eventual adult body size, breeding propensity, and size and volume of clutches they eventually produced to examine the relationship between growth and fitness in this population. We indexed body size by calculating PC1 scores based on either culmen and tarsus, or culmen, tarsus, and mass. Gosling (PC scores based on culmen and tarsus) size was positively correlated with resighting rate (P = 0.005), indicating that larger goslings survived at a higher rate than did smaller goslings. Gosling size was correlated with adult size of the same individuals (P = 0.0004). Larger goslings were more likely to breed as 2- or 3-yr-olds than were medium or small goslings (P = 0.008). Larger adult brant laid more eggs (P = 0.03) and produced clutches with greater total volume (P = 0.03) than did smaller brant. Given the important role of foraging environment in growth of goslings, these data suggest an important role of early environment in determining life-history traits.
Christophe Minier - One of the best experts on this subject based on the ideXlab platform.
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Genotoxicity in the rivers from the Brantas catchment (East Java, Indonesia): occurrence in sediments and effects in Oreochromis niloticus (Linnæus 1758)
Environmental Science and Pollution Research, 2020Co-Authors: Yenny Risjani, Géraldine Loppion, Jérôme Couteau, Yunianta Yunianta, Ita Widowati, Alfi Hermawati, Christophe MinierAbstract:This paper reports the first data from an integrated study investigating genotoxicity in the Brantas River, Java, Indonesia. Results showed that organic sediment extracts from the sites in the Brantas Delta retained genotoxic compounds identified using the SOS Chromotest and that the Aloo River and, to a lesser extent, the Surabaya River were the most contaminated studied sites. This genotoxicity was attributable to compounds that did not require any bioactivation under the test conditions. Occurrence of genotoxic effects was further investigated in erythrocytes from Nile tilapia, Oreochromis niloticus . High numbers of micronuclei were counted, especially in fish sampled in the rivers of the Brantas Delta. Moreover, cytoplasmic alterations which could be indicative of the presence of lipofuscin were found in the cytoplasm of the fish blood cells, especially in fish from the Aloo, Surabaya and Kalimas rivers. Altogether, our data showed that genotoxicity is occurring in fish living in rivers of the delta of the Brantas River and suggest that sediments from these sites may constitute a major source of pollution and hazard for species living or feeding in the area.
