ALBERT

Description: Ichthyoplankton was sampled in 9 exploratory cruises in the sea off Buenos Aires province (Argentina), Uruguay and Brazil, during the spawning peak of the anchovy in spring-early summer and mid-autumn. The most abundant speices in the ichthyoplankton was Engraulis anchoita, representing 88. of the eggs and 76. of the larvae collected in all the cruises. These percentages vary boath regionally and seasonally; as regards eggs, the lowest percentage (10. ) was found in January. The distribution of anchovy eggs and larvae, covered almost entirely the surveyed area, with the exception of hte region influenced by the River Plate estuary. Minimum salinity tolerance for the species eggs was 23.5o/oo. The eastern limit of the distribution of anchovy eggs, extends in spring-early summer to the 200 m isobath in the northern part of the study area, whereas in the south rarely extends beyond the 50 m isobath. Anchovy larvae showed a wider distribution, penetrating in November and December in the brackish waters of the Samborombón bay, extending over more off-shore waters in January. As the spawning season progressed a southwards movement of intensive reproduction nuclei was observed. The average daily egg production during spring-early summer was estimated at 260 anchovy eggs/m2/day; in autumn, a ten-fold reduction of this production was observed. On the basis of the seasonal egg production for spring-early summer, calculated at 3.5238 E15 eggs and the larvae census carried out in mid-January a 98.2. mortality during the imbryonic and larval stages of the anchovy could be assumed. The spawning biomass of the anchovy during this period was calculated at 2,514,970 t. Preliminary results on the vertical distribution of anchovy eggs and larvae show that their distribution is generally restricted to the upper 50 m water layer, with higher concentrations at 10 to 25 m depths.

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Description: Published

Description: Clupeiformes, Engraulidae, evaluación de efectivos, huevos de peces, distribución vertical, poblaciones desovantes

Description: A bongo sampler fifted with nets of two different mesh sizes, 330 and 505 u. was used to collected 137 ichthyoplankton samples in the coastal areas off Buenos Aires Province in October, 1981. The efficiency of the two meshes for catching anchovy eggs and larvae and total ichthyoplankton was examined. The statistical analysis of the samples shows that there are no significant differences between the numbers of anchovy and total eggs collected by the different meshes. As regards anchovy and total larvae the finer mesh showed as significantly higher catching efficiency. The results of this partial estimate do not suggest that a major revision of the total assessment of the complete stock is necessary.

Description: Publisher permission

Description: Published

Description: Clupeiformes, Engraulidae, Engraulis anchoita, evaluación de efectivos, huevos de peces

Description: Fecundity and spawning frequency were estimated in the northern(off Buenos Aires Province)and southern (patagonian)argentine anchovy Engraulis anchoita populations in 1993, during the peak of the spawning season. Relative fecundity, expressed as eggs per ovary-free weight was 574±21 (CI 95. ) and 605±49 (CI 95. ) in the northern and southern populations. The difference was not statistically significant between stocks (P0.13). Relative fecundity was higher in anchovies larger than 130 mm. The mean batch fecundity for the northern and southern populations was 13675±856 (CI 95. ) and21677±2.753 (CI 95. ) respectively. Batch fecundity (F)expressed as alinear function of ovary-free weight (W)was: F=-1310+649 * W(northern), F=-5935+786 * W (southern). The daily spawning incidence was estimated in 12,6. ±3.3 (CI 95. ) for the northern population and 15,5. ±8.5 (CI 95. ) for the southern. The females spawned about every 7.9 and 6.5 days respectively. A low incidence of alpha and bethastages atresia in ovaries was founded in both populations (less than 2. yolked oocytes affected). Relative egg production for anchovies ages 1-2 and ages 2-3 were estimated to contribute 74. and 64. to egg production in the northern and southern stocks during the peak of the spawning season. It was observed a direct relationship between collections with male-dominated schools and females with hidrated and recent post-ovulattory follicles.

Description: Publisher permission

Description: Published

Description: Engraulidae, Engraulis anchoita, anchoíta, ovarios, fecundidad, estaciones de desove, huevos de peces, poblaciones desovantes

Description: Ichthyoplankton samples were collected during an exploratory cruise carried out by the RV Dr.Holmberg during the spring spawning peak of 1981 in the sea-shelf off Buenos Aires province (Argentina). The cruise was designed to carry out population studies in a restricted area of intense reproduction activity, in order to gather information on the time-space patterns of distribution of the eggs and larvae of the species.

Description: Publisher permission

Description: Published

Description: Clupeiformes, Engraulidae, larvas de peces, huevos de peces, curvas de crecimiento, condiciones controladas, mortalidad

Description: Lagrangian changes in distribution and survival within an anchovy egg and larvae patch were studied by means of multiple opening/closing sampling following a free drifting buoy. The buoy was equipped with a radar reflector and flashing light, and it was connected to a current cross drogue floating at 15 m depth, which corresponded to the main egg and larvae concentration within the patch. The drifter was launched on the Buenos Aires continental shelf, off Necochea during the spring spawning peak of 1983. Three discrete depths (within, below and above the thermocline)were repeatedly sampled close to the drogue with a Motoda sampler. Egg and larval abundances in the vicinity of the drogue were monitored at 3/4 hour intervals for a period of three days. Each plankton station included a set of hydrographic and climatological data registered simultaneously. The efficiency of the drogue as a Lagrangian marker was examined by means of the application of multifactorial ANOVA to test the significance of variability between days, light regime, sampling depths, population structure and their interactions. Wind drag on the surface unit did not significantly affect the trajectory of the drogue. Patterns of embryonic and larval vertical distribution are discussed by means of the variations in the centre of mass, in the vertical dispersion and patchiness indexes for each developmental stage analyzed. There is evidence of diel vertical migration in larvae larger than 8 mm SL. Although the incidence of feeding based on observations of the presence of undigested food in the gut content of larvae was low, a daily feeding pattern over a 14-hour period starting after sunrise, was evident. Evening ascent of larger larvae was not related to feeding activity. A single equation two-stage model, assuming age dependent mortality in the embryonic and post-larval period is derived and compared to standard models based on constant exponential decay during each developmental phase.

Description: Publisher permission

Description: Published

Description: Engraulidae, Engraulis anchoita, anchoíta, relevamientos ictioplanctónicos, relevamientos pesqueros, larvas de peces, huevos de peces, distribución vertical, abundancia, boyas a la deriva, efectos ambientales, alimentación, supervivencia, migraciones verticales

Description: This dissertation is focused on the study of implications of spatial patterns on survival of eggs and larvae and subsequent recruitment of the SW Atlantic anchovy, Engraulis anchoita. The study of distribution patterns is encompassed within the conceptual framework of the analysis of reproductive strategies of marine bony fish, as adaptations that enable them to cope with and actively exploit environmental variability, regulating their abundance and avoiding extinction. The SW Atlantic anchovy, is ideally suitable for studies on reproductive biology and recruitment on a comparative basis. Its spawning and nursery grounds are located in very diverse ecosystems. This variety refers to their physico-chemical properties, carrying capacity, the influence of several water masses, and the contribution of fresh water runoffs from different origins. Important physical features are seasonal thermocline formation, and the presence of transitional regions such as oceanic, shelf-break and tidal shelf fronts, and upwelling areas. The aim of this dissertation was to study the biological response to that environmental heterogeneity. The central issue of the discussion was the implication of that apparent lack of association between reproductive activity and environmental conditions, on the rates of growth and mortality during the early developmental stages, and subsequent recruitment. As a working hypothesis the existence of some degree of dependence between those population attributes and the evolution of the distributional patterns during the early ontogeny was postulated. To prove this assumption distributions were studied not only in their usual connotation (i.e. spatial arrangement, geographic location), but also in their ecological and statistical sense, in a variety of time-space scales, from the Eulerian and Lagrangian perspectives. The final outcome, based on the identification of factors influencing the survival of the early developmental stages of the species, was the derivation of models that could describe mechanisms of demographic regulation.

Description: Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales.

Description: Tesis (Doctorado). Copia en PDF: portada, índice, resumen, referencias bibliográficas.

Description: Engraulis anchoita, Engraulidae, huevos, larvas de peces, ictioplancton, biomasa, reproducción, distribución, desarrollo de estadíos, desarrollo larval, desarrollo embrionario, mortalidad, evaluación de efectivos, condiciones ambientales

Description: This paper reviews the information on pelagic and demersal fish eggs and larvae, describing the distribution and seasonality of different species and their arrangement in icthyoplankton assemblages in the Southern patagonian waters. It also reports on 11 surveys conducted by INIDEP during 1992-1995. A total of 488 ichthyoplankton samples were analyzed. Fish eggs have been recognized in 47. of all ichthyoplankton samples. They belong to three species: Coelorhynchus fasciatus, Macrourus whitsoni and Micromesistius australis. Fish larvae of 23 species and 17 families have been identified in 96. of all samples analyzed. Spawning of most species begins in autumn, and progresses through winter, when the southern blue whiting and grenadier fish contribute to more than half of all eggs present in our samples. Nototheniid and myctophiid larvae were caught during all year long. Four larval groups were detected using cluster analysis: the first group, formed exclusively by nototheniids, which occupied a vast area on the continental shelf between 100 and 200 m depth, the second formed by Agonopsis chiloensis, Eleginops maclovinus, Macruronus magellanicus and Sprattus fuegensis in coastal waters, the third formed by myctophiids, Gymnoscopelus spp. and Micromesistius australis, inhabit the outer continental shelf and slope, and the fourth included Protomyctophum spp., Krefftichthys anderssoni and Bathylagus antarcticus, species typically found in Subantarctic waters of the Malvinas Current. Comparing the distribution of eggs and larvae of blue whiting from collections obtained during the 70's and 80's, with those of recent surveys, it is evident, that a significant contraction of the spawning grounds of the species has take place, particularly to the west of the archipelago.

Description: Sánchez, R.P.; ed. 1999. Reproductive habitat, biology and acoustic biomass estiomates of the southern blue whiting (Micromesistius australis) in the sea off southern patagonia. INIDEP Documento Científico, 5: 93 p.

Description: Published

Description: larvas de peces, huevos de peces, distribución estacional, abundancia de asociaciones, ictioplancton

Description: Genome-wide patterns of variation across individuals provide a powerful source of data for uncovering the history of migration, range expansion, and adaptation of the human species. However, high-resolution surveys of variation in genotype, haplotype and copy number have generally focused on a small number of population groups. Here we report the analysis of high-quality genotypes at 525,910 single-nucleotide polymorphisms (SNPs) and 396 copy-number-variable loci in a worldwide sample of 29 populations. Analysis of SNP genotypes yields strongly supported fine-scale inferences about population structure. Increasing linkage disequilibrium is observed with increasing geographic distance from Africa, as expected under a serial founder effect for the out-of-Africa spread of human populations. New approaches for haplotype analysis produce inferences about population structure that complement results based on unphased SNPs. Despite a difference from SNPs in the frequency spectrum of the copy-number variants (CNVs) detected--including a comparatively large number of CNVs in previously unexamined populations from Oceania and the Americas--the global distribution of CNVs largely accords with population structure analyses for SNP data sets of similar size. Our results produce new inferences about inter-population variation, support the utility of CNVs in human population-genetic research, and serve as a genomic resource for human-genetic studies in diverse worldwide populations.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Jakobsson, Mattias -- Scholz, Sonja W -- Scheet, Paul -- Gibbs, J Raphael -- VanLiere, Jenna M -- Fung, Hon-Chung -- Szpiech, Zachary A -- Degnan, James H -- Wang, Kai -- Guerreiro, Rita -- Bras, Jose M -- Schymick, Jennifer C -- Hernandez, Dena G -- Traynor, Bryan J -- Simon-Sanchez, Javier -- Matarin, Mar -- Britton, Angela -- van de Leemput, Joyce -- Rafferty, Ian -- Bucan, Maja -- Cann, Howard M -- Hardy, John A -- Rosenberg, Noah A -- Singleton, Andrew B -- G0701075/Medical Research Council/United Kingdom -- MR/K01417X/1/Medical Research Council/United Kingdom -- Intramural NIH HHS/ -- England -- Nature. 2008 Feb 21;451(7181):998-1003. doi: 10.1038/nature06742.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Center for Computational Medicine and Biology, University of Michigan, Ann Arbor, Michigan 48109, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/18288195" target="_blank"〉PubMed〈/a〉

Description: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Grant, Robert M -- Buchbinder, Susan -- Cates, Willard Jr -- Clarke, Edith -- Coates, Thomas -- Cohen, Myron S -- Delaney, Martin -- Flores, Guiselly -- Goicochea, Pedro -- Gonsalves, Gregg -- Harrington, Mark -- Lama, Javier R -- MacQueen, Kathleen M -- Moore, John P -- Peterson, Leigh -- Sanchez, Jorge -- Thompson, Melanie -- Wainberg, Mark A -- New York, N.Y. -- Science. 2005 Sep 30;309(5744):2170-1.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Gladstone Institute of Virology and Immunology, San Francisco, CA, USA. rgrant@itsa.ucsf.edu〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/16195446" target="_blank"〉PubMed〈/a〉

Description: Land-use change occurs nowhere more rapidly than in the tropics, where the imbalance between deforestation and forest regrowth has large consequences for the global carbon cycle. However, considerable uncertainty remains about the rate of biomass recovery in secondary forests, and how these rates are influenced by climate, landscape, and prior land use. Here we analyse aboveground biomass recovery during secondary succession in 45 forest sites and about 1,500 forest plots covering the major environmental gradients in the Neotropics. The studied secondary forests are highly productive and resilient. Aboveground biomass recovery after 20 years was on average 122 megagrams per hectare (Mg ha(-1)), corresponding to a net carbon uptake of 3.05 Mg C ha(-1) yr(-1), 11 times the uptake rate of old-growth forests. Aboveground biomass stocks took a median time of 66 years to recover to 90% of old-growth values. Aboveground biomass recovery after 20 years varied 11.3-fold (from 20 to 225 Mg ha(-1)) across sites, and this recovery increased with water availability (higher local rainfall and lower climatic water deficit). We present a biomass recovery map of Latin America, which illustrates geographical and climatic variation in carbon sequestration potential during forest regrowth. The map will support policies to minimize forest loss in areas where biomass resilience is naturally low (such as seasonally dry forest regions) and promote forest regeneration and restoration in humid tropical lowland areas with high biomass resilience.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Poorter, Lourens -- Bongers, Frans -- Aide, T Mitchell -- Almeyda Zambrano, Angelica M -- Balvanera, Patricia -- Becknell, Justin M -- Boukili, Vanessa -- Brancalion, Pedro H S -- Broadbent, Eben N -- Chazdon, Robin L -- Craven, Dylan -- de Almeida-Cortez, Jarcilene S -- Cabral, George A L -- de Jong, Ben H J -- Denslow, Julie S -- Dent, Daisy H -- DeWalt, Saara J -- Dupuy, Juan M -- Duran, Sandra M -- Espirito-Santo, Mario M -- Fandino, Maria C -- Cesar, Ricardo G -- Hall, Jefferson S -- Hernandez-Stefanoni, Jose Luis -- Jakovac, Catarina C -- Junqueira, Andre B -- Kennard, Deborah -- Letcher, Susan G -- Licona, Juan-Carlos -- Lohbeck, Madelon -- Marin-Spiotta, Erika -- Martinez-Ramos, Miguel -- Massoca, Paulo -- Meave, Jorge A -- Mesquita, Rita -- Mora, Francisco -- Munoz, Rodrigo -- Muscarella, Robert -- Nunes, Yule R F -- Ochoa-Gaona, Susana -- de Oliveira, Alexandre A -- Orihuela-Belmonte, Edith -- Pena-Claros, Marielos -- Perez-Garcia, Eduardo A -- Piotto, Daniel -- Powers, Jennifer S -- Rodriguez-Velazquez, Jorge -- Romero-Perez, I Eunice -- Ruiz, Jorge -- Saldarriaga, Juan G -- Sanchez-Azofeifa, Arturo -- Schwartz, Naomi B -- Steininger, Marc K -- Swenson, Nathan G -- Toledo, Marisol -- Uriarte, Maria -- van Breugel, Michiel -- van der Wal, Hans -- Veloso, Maria D M -- Vester, Hans F M -- Vicentini, Alberto -- Vieira, Ima C G -- Bentos, Tony Vizcarra -- Williamson, G Bruce -- Rozendaal, Danae M A -- England -- Nature. 2016 Feb 11;530(7589):211-4. doi: 10.1038/nature16512. Epub 2016 Feb 3.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Forest Ecology and Forest Management Group, Wageningen University, PO Box 47, 6700 AA Wageningen, The Netherlands. ; PO Box 23360, Department of Biology, University of Puerto Rico, San Juan, PR 00931-3360, Puerto Rico. ; Spatial Ecology and Conservation Lab, Department of Geography, University of Alabama, Tuscaloosa, Alabama 35487, USA. ; Instituto de Investigaciones en Ecosistemas y Sustentabilidad, Universidad Nacional Autonoma de Mexico, CP58190, Morelia, Michoacan, Mexico. ; Department of Ecology and Evolutionary Biology, Brown University, Providence, Rhode Island 02912, USA. ; Department of Ecology and Evolutionary Biology, University of Connecticut, Storrs, Connecticut 06269, USA. ; Department of Forest Sciences, Luiz de Queiroz College of Agriculture, University of Sao Paulo, Avenida Padua Dias 11, 13418-900, Piracicaba, Sao Paulo, Brazil. ; SI ForestGEO, Smithsonian Tropical Research Institute, Roosevelt Avenue, Tupper Building - 401, Balboa, Ancon, Panama, Panama ; German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Deutscher Platz 5e, 04103 Leipzig, Germany. ; Institute for Biology, Leipzig University, Johannisallee 21, 04103 Leipzig, Germany. ; Departamento de Botanica, Universidade Federal de Pernambuco, Pernambuco, CEP 50670-901, Brazil. ; Department of Sustainability Science, El Colegio de la Frontera Sur, Unidad Campeche, Av. Rancho Poligono 2A, Parque Industrial Lerma, Campeche, Campeche, CP 24500, Mexico. ; Department of Ecology and Evolutionary Biology, Tulane University, New Orleans, Louisiana 70130, USA. ; Smithsonian Tropical Research Institute, Roosevelt Avenue, Tupper Building - 401, Balboa, Ancon, Panama, Panama ; Biological and Environmental Sciences, University of Stirling, Stirling FK9 4LA, UK. ; Department of Biological Sciences, Clemson University, 132 Long Hall, Clemson, South Carolina 29634, USA. ; Centro de Investigacion Cientifica de Yucatan, AC, Unidad de Recursos Naturales, Calle 43 No. 130, Colonia Chuburna de Hidalgo, CP 97200, Merida, Yucatan, Mexico. ; Earth and Atmospheric Sciences Department, University of Alberta, Edmonton, Alberta T6G 2E3, Canada. ; Departamento de Biologia Geral, Universidade Estadual de Montes Claros, Montes Claros, Minas Gerais, CEP 39401-089, Brazil. ; Fondo Patrimonio Natural para la Biodiversidad y Areas Protegidas, Calle 72 No. 12-65 piso 6, Bogota, Colombia. ; Biological Dynamics of Forest Fragments Project, Environmental Dynamics Research Coordination, Instituto Nacional de Pesquisas da Amazonia, Manaus, Amazonas, CEP 69067-375, Brazil. ; Centre for Crop Systems Analysis, Wageningen University, PO Box 430, 6700 AK Wageningen, The Netherlands. ; Knowledge, Technology and Innovation Group, Wageningen University, PO Box 8130, 6700 EW Wageningen, The Netherlands. ; Coordenacao de Tecnologia e Inovacao, Instituto Nacional de Pesquisas da Amazonia, Avenida Andre Araujo, 2936 - Aleixo, 69060-001 Manaus, Brazil. ; Department of Physical and Environmental Sciences, Colorado Mesa University, 1100 North Avenue, Grand Junction, Colorado 81501, USA. ; Department of Environmental Studies, Purchase College (State University of New York), Purchase, New York 10577, USA. ; Instituto Boliviano de Investigacion Forestal (IBIF), FCA-UAGRM, Casilla 6204, Santa Cruz de la Sierra, Bolivia. ; World Agroforestry Centre (ICRAF), PO Box 30677 - 00100, Nairobi, Kenya. ; Department of Geography, University of Wisconsin-Madison, 550 North Park Street, Madison, Wisconsin 53706, USA. ; Departamento de Ecologia y Recursos Naturales, Facultad de Ciencias, Universidad Nacional Autonoma de Mexico, Mexico 04510 DF, Mexico. ; Department of Ecology, Evolution and Environmental Biology, Columbia University, New York, New York 10027, USA. ; Section of Ecoinformatics and Biodiversity, Department of Bioscience, Aarhus University, Aarhus 8000, Denmark. ; Departamento de Ecologia, Instituto de Biociencias, Universidade de Sao Paulo, Rua do Matao, travessa 14, No. 321, Sao Paulo, CEP 05508-090, Brazil. ; Universidade Federal do Sul da Bahia, Centro de Formacao em Ciencias Agroflorestais, Itabuna-BA, 45613-204, Brazil. ; Department of Ecology, Evolution, &Behavior, University of Minnesota, Saint Paul, Minnesota 55108, USA. ; Department of Plant Biology, University of Minnesota, Saint Paul, Minnesota 55108, USA. ; School of Social Sciences, Geography Area, Universidad Pedagogica y Tecnologica de Colombia (UPTC), Tunja, Colombia. ; Department of Geography, 4841 Ellison Hall, University of California, Santa Barbara, California 93106, USA. ; Department of Biology, University of Maryland, College Park, Maryland 20742, USA. ; Yale-NUS College, 12 College Avenue West, Singapore 138610. ; Department of Biological Sciences, National University of Singapore, 14 Science Drive 4, Singapore 11754. ; Departamento de Agricultura, Sociedad y Ambiente, El Colegio de la Frontera Sur - Unidad Villahermosa, 86280 Centro, Tabasco, Mexico. ; Institute for Biodiversity and Ecosystem Dynamics (IBED), University of Amsterdam, PO Box 94248, 1090 GE Amsterdam, The Netherlands. ; Bonhoeffer College, Bruggertstraat 60, 7545 AX Enschede, The Netherlands. ; Museu Paraense Emilio Goeldi, CP 399, CEP 66040-170, Belem, Brazil. ; Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana 70803-1705, USA. ; Department of Biology, University of Regina, 3737 Wascana Parkway, Regina, Saskatchewan S4S 0A2, Canada.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/26840632" target="_blank"〉PubMed〈/a〉