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1.
Ecol Appl ; 30(3): e02058, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31838775

RESUMO

Most spatial conservation planning for wide-ranging or migratory species is constrained by poor knowledge of species' spatiotemporal dynamics and is only based on static species' ranges. However, species have substantial variation in abundance across their range and migratory species have important spatiotemporal population dynamics. With growing ecological data and advancing analytics, both of these can be estimated and incorporated into spatial conservation planning. However, there is limited information on the degree to which including this information affects conservation planning. We compared the performance of systematic conservation prioritizations for different scenarios based on varying the input species' distributions by ecological metric (abundance distributions versus range maps) and temporal sampling resolution (weekly, monthly, or quarterly). We used the example of a community of 41 species of migratory shorebirds that breed in North America, and we used eBird data to produce weekly estimates of species' abundances and ranges. Abundance distributions at a monthly or weekly resolution led to prioritizations that most efficiently protected species throughout the full annual cycle. Conversely, spatial prioritizations based on species' ranges required more sites and left most species insufficiently protected for at least part of their annual cycle. Prioritizations with only quarterly species ranges were very inefficient as they needed to target 40% of species' ranges to include 10% of populations. We highlight the high value of abundance information for spatial conservation planning, which leads to more efficient and effective spatial prioritization for conservation. Overall, we provide evidence that spatial conservation planning for wide-ranging migratory species is most robust and efficient when informed by species' abundance information from the full annual cycle.


Assuntos
Cruzamento , Conservação dos Recursos Naturais , América do Norte , Dinâmica Populacional
2.
Mar Pollut Bull ; 48(5-6): 504-13, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14980466

RESUMO

In 2000, we collected blood from long-tailed ducks (Clangula hyemalis) and blood and eggs from common eiders (Somateria mollissima) at near-shore islands in the vicinity of Prudhoe Bay, Alaska, and at a reference area east of Prudhoe Bay. Blood was analyzed for trace elements and egg contents were analyzed for trace elements, organochlorine pesticides, polychlorinated biphenyls, and polycyclic aromatic hydrocarbons. Except for Se (mean=36.1 microg/g dry weight (dw) in common eiders and 48.8 microg/g dw in long-tailed ducks), concentrations of trace elements in blood were low and, although several trace elements differed between areas, they were not consistently higher at one location. In long-tailed ducks, Se in blood was positively correlated with activities of two serum enzymes, suggestive of an adverse effect of increasing Se levels on the liver. Although common eiders had high Se concentrations in their blood, Se residues in eggs were low (mean=2.28 microg/g dw). Strontium and Ni were higher in eggs near Prudhoe Bay than at the reference area, but none of the other trace elements or organic contaminants in eggs differed between locations. Concentrations of Ca, Sr, Mg, and Ni differed among eggs having no visible development, early-stage embryos, or late-stage embryos. Residues of 4,4'-DDE, cis-nonachlor, dieldrin, hexachlorobenzene, oxychlordane, and trans-nonachlor were found in 100% of the common eider eggs, but at low concentrations (means of 2.35-7.45 microg/kg wet weight (ww)). The mean total PCB concentration in eggs was 15.12 microg/kg ww. Of PAHs tested for, residues of 1- and 2-methylnaphthalene and naphthalene were found in 100% of the eggs, at mean concentrations of 0.36-0.89 microg/kg ww.


Assuntos
Patos , Poluentes Ambientais/sangue , Inseticidas/sangue , Muda , Bifenilos Policlorados/sangue , Selênio/sangue , Poluentes da Água/sangue , Alaska , Animais , Monitoramento Ambiental , Poluentes Ambientais/análise , Feminino , Inseticidas/análise , Óvulo/química , Bifenilos Policlorados/análise , Selênio/análise , Distribuição Tecidual , Poluentes da Água/análise
3.
Am Nat ; 149(6): 1051-70, 1997 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18811263

RESUMO

Females in lek-breeding species appear to copulate with a small subset of the available males. Such strong directional selection is predicted to decrease additive genetic variance in the preferred male traits, yet females continue to mate selectively, thus generating the lek paradox. In a study of buff-breasted sandpipers (Tryngites subruficollis), we combine detailed behavioral observations with paternity analyses using single-locus minisatellite DNA probes to provide the first evidence from a lek-breeding species that the variance in male reproductive success is much lower than expected. In 17 and 30 broods sampled in two consecutive years, a minimum of 20 and 39 males, respectively, sired offspring. This low variance in male reproductive success resulted from effective use of alternative reproductive tactics by males, females mating with solitary males off leks, and multiple mating by females. Thus, the results of this study suggests that sexual selection through female choice is weak in buff-breasted sandpipers. The behavior of other lek-breeding birds is sufficiently similar to that of buff-breasted sandpipers that paternity studies of those species should be conducted to determine whether leks generally are less paradoxical than they appear.

4.
Am J Obstet Gynecol ; 115(3): 291-7, 1973 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-4682821

RESUMO

PIP: 518 patients were inserted with T-Cu120sq. mm(168), T-Cu200sq. mm(250), and Lippes Loop (60) for a 20-month comparative study of the devices. Events of spotting, dysmenorrhea, metrorrhagia, and secondary side effects were less in the T-Cu devices. The expulsion rate was higher for the T-Cu200sq. mm than T-Cu120sq. mm, but for all other types of termination the T-Cu120sq. mm was highest. Termination rate for Lippes Loops was 19.66; T-Cu120sq. mm 32.03; and T-Cu200sq. mm, 24.17. Insertion was easier with T devices.^ieng


Assuntos
Cobre , Dispositivos Intrauterinos , Feminino , Humanos , Dispositivos Intrauterinos/efeitos adversos , Métodos , Gravidez
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