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151.
In some vertebrate species, parents create a large brood or litter then, in the event of unfavourable ecological conditions, apparently allow the number of offspring to be adaptively reduced through siblicide. But how is sibling aggression regulated so that deaths occur only in unfavourable conditions? One proposed mechanism is brood size-dependent aggression. Two experiments tested for this mechanism by reducing three-chick broods of blue-footed boobies either during or after the period of dominance hierarchy establishment. In neither experiment did aggression of the two eldest and highest ranking chicks decline after removal of the youngest broodmate, in comparison with controls. These results suggest that dominant booby chicks do not become less aggressive to each other after disappearance of their youngest broodmate and that this species does not show brood size dependent aggression. Elder blue-footed booby chicks increase their attacks on broodmates when they receive less food, and this mechanism may be sufficient to tailor brood size to food availability. 相似文献
152.
Marcel Clusa Carlos Carreras Marta Pascual Stephen J. Gaughran Susanna Piovano Cristina Giacoma Gloria Fernández Yaniv Levy Jesús Tomás Juan Antonio Raga Fulvio Maffucci Sandra Hochscheid Alex Aguilar Luis Cardona 《Marine Biology》2014,161(3):509-519
Loggerhead turtles nesting in the Mediterranean Sea exhibit remarkable genetic structuring. This paper tests the hypothesis that young loggerhead turtles from different rookeries do not distribute homogeneously among the major Mediterranean foraging grounds, due to a complex pattern of surface currents. We extracted long fragments of mitochondrial DNA from 275 stranded or bycaught juvenile turtles from six foraging grounds (Catalano-Balearic Sea, Algerian basin, Tyrrhenian Sea, Adriatic Sea, northern Ionian Sea and southern Levantine Sea). We used a Bayesian mixed-stock analysis to estimate the contributions from rookeries in the Mediterranean, the North-west Atlantic and Cape Verde to the studied foraging grounds. Differences were found in the relative contribution of juvenile turtles of Atlantic and Mediterranean origin to each foraging ground. A decreasing proportion of Atlantic juveniles was detected along the main surface current entering the Mediterranean, with a high prevalence of turtles from eastern Florida in the Algerian basin and lower numbers elsewhere. In regard to the turtles of Mediterranean origin, juveniles from Libya prevailed in central and western Mediterranean foraging grounds other than the Algerian basin. Conversely, the Adriatic Sea was characterised by a large presence of individuals from western Greece, while the southern Levantine Sea was inhabited by a heterogeneous mix of turtles from the eastern Mediterranean rookeries (Turkey, Lebanon and Israel). Overall, the distribution of juveniles may be related to surface circulation patterns in the Mediterranean and suggests that fisheries might have differential effects on each population depending on the overlap degree between foraging and fishing grounds. 相似文献
153.
Linares C Garrabou J Hereu B Diaz D Marschal C Sala E Zabala M 《Conservation biology》2012,26(1):88-96
Although the rapid recovery of fishes after establishment of a marine reserve is well known, much less is known about the response of long-lived, sessile, benthic organisms to establishment of such reserves. Since antiquity, Mediterranean red coral (Corallium rubrum) has been harvested intensively for use in jewelry, and its distribution is currently smaller than its historical size throughout the Mediterranean Sea. To assess whether establishment of marine reserves is associated with a change in the size and number of red coral colonies that historically were not harvested sustainably, we analyzed temporal changes in mean colony diameter and density from 1992 to 2005 within red coral populations at different study sites in the Medes Islands Marine Reserve (established in 1992) and in adjacent unprotected areas. Moreover, we compared colony size in the Medes Islands Marine Reserve, where recreational diving is allowed and poaching has been observed after reserve establishment, with colony size in three other marine protected areas (Banyuls, Carry-le-Rouet, and Scandola) with the enforced prohibition of fishing and diving. At the end of the study, the size of red coral colonies at all sampling sites in the Medes Islands was significantly smaller than predicted by growth models and smaller than those in marine protected areas without fishing and diving. The annual number of recreational dives and the percent change in the basal diameter of red coral colonies were negatively correlated, which suggests that abrasion by divers may increase the mortality rates of the largest red coral colonies within this reserve . Our study is the first quantitative assessment of a poaching event, which was detected during our monitoring in 2002, inside the marine reserve. Poaching was associated with a loss of approximately 60% of the biomass of red coral colonies. 相似文献
154.
Kurt Paschke Juan Pablo Cumillaf Sergio Loyola Paulina Gebauer Mauricio Urbina María Eugenia Chimal Cristina Pascual Carlos Rosas 《Marine Biology》2010,157(1):7-18
Episodes of hypoxia are common in the marine environment, and their ecological effects depend, in part, on their severity
and duration. Many species of decapod crustaceans reside in areas with fluctuating oxygen regimens. Physiological mechanisms
enhance the ability of these crustaceans to cope with acute episodes of hypoxia. Southern king crab, Lithodes santolla, fishery is important in the south of South America, and some data describe fishing zones with low dissolved oxygen (DO) levels
(3.5 mgO2 l−1, i.e., 8.3 kPa). Our main objective was to evaluate the effect of dissolved oxygen level on respiratory metabolism, nutritional
physiology, and immunological condition of L. santolla juveniles. Individual animals were exposed for 10 days to different oxygen tensions (2.1, 4.2, 8.5, 12.7, and 21.1 kPa) to
quantify the oxygen consumption rate; thereafter, blood oxyhemocyanin (Hc), protein concentration, as well as hemocytes, were
sampled. Freeze-dried animals were dissected, and digestive gland metabolites (glycogen, protein, glucose, cholesterol, acylglycerol,
and lactate) and digestive enzyme activity (general protease, trypsin, and chymotrypsin), as well as gill lactate dehydrogenase
(LDH) activity, were quantified. In the present study, Lithodes santolla showed a critical oxygen tension between 4 and 9 kPa, indicating that this crab species is more sensitive to DO than other
crustacean species. Protein and Hc concentrations followed a similar pattern to that of oxygen consumption. Digestive gland
glycogen and protein concentration did not change after 10 days at different oxygen exposures, but glucose, cholesterol, and
acylglycerol concentrations decreased linearly and proportionally to the available oxygen in the water. As in other decapods,
chymotrypsin showed over 90% of the total quantified proteases activity. Chymotrypsin activity together with total proteases
and trypsin was not affected by the environmental oxygen tension. Gill LDH and digestive gland lactate followed a similar
increase at lower environmental oxygen tension but dropped sharply at the lowest tension (2.1 kPa). Dissolved oxygen affected
also the immune system through reduction of hemocytes. This could provide a critical window for opportunistic pathogens to
become established when crabs are exposed to hypoxic conditions. L. santolla juveniles show a moderate tolerance to low oxygen availability by modifying the concentration of hemolymph proteins, mainly
OxyHc, some digestive gland metabolites, and by activating the anaerobic metabolism. This allows L. santolla juveniles to inhabit temporarily low oxygen zones in the deep ocean and suggests an advantage for culture conditions. 相似文献
155.
Hugh Drummond Roxana Torres Cristina Rodríguez Juarez Sin-Yeon Kim 《Behavioral ecology and sociobiology》2010,64(4):647-655
In multitudinous breeding colonies, kin interactions could go unnoticed because we are unaware of the kinship among adults
we observe. Evidence of cooperation and competition between close adult kin in a blue-footed booby colony was sought by analyzing
patterns of natal dispersal and proximity of nests. Male and female recruits nested closer to their own natal sites than to
their parents’ current sites. Males (only) dispersed less far when both parents were present than when no parent or one parent
was present, but not selectively close to fathers versus mothers when these were divorced. Neither parental presence nor parental
proximity affected breeding success of recruits of either sex. Although distances between the nests of simultaneously recruiting
broodmates were unrelated to their sex, males dispersed 13.1 m less when a sister was present than when a brother was present.
Neither sex was affected in its dispersal distance by the presence or hatching order/dominance of a broodmate. Neither sex
was affected in its breeding success by the presence versus absence of a broodmate, although female success increased with
proximity of their brothers. Parents and sisters may actively or passively help males establish their first territories near
their natal sites and nearby brothers may help females in their first breeding attempts; otherwise, boobies do not influence
each other’s natal dispersal and first breeding success. It appears that boobies do not nest selectively close to or far from
their parents, offspring, or broodmates. Why there is apparently so little cooperation and altruism between close adult relatives
in booby colonies is puzzling. 相似文献
156.
Cristina A.R. De Carvalho Walter Leal Filho William H.G. Hale 《The Environmentalist》1999,18(4):223-229
This paper describes the problems encountered in developing environmental education in Federal protected areas in Brazil. Results of a survey on the current status of environmental education in four categories of Federal protected areas; namely national parks, biological reserves, ecological stations and environmental protection areas, are described and discussed. The study suggests that the development of environmental education in protected areas in the country has several limitations: financial resources, lack of training, material resources and a lack of policy on environmental education. It also identifies that some of these problems seem to be inter-related with those of the National System of Conservation Units of the country which may result in a retarding of the development of environmental education in such areas. 相似文献
157.
This work proposes a semi-quantitative risk assessment methodology, which was applied and tested in the Ship Building Industry. It covers a wide range of risks related to occupational accidents in a shipbuilding yard environment, more specifically at Arsenal do Alfeite, a large shipyard in Portugal. The initial qualitative analysis focuses on the bow-tie diagram technique but it also integrates concepts and classifications schemes defined by the Eurostat within the European Statistics on Accidents at Work (ESAW) Project. The structure of the diagram enables the identification of the relevant accident’s causal pathways and their consequences at the same time as it identifies the existing or needed safety barriers. In what concerns the semi-quantitative assessment, the accident risk level and acceptance criteria were established through a scoring system, using national data on accident statistics for the sub-sector: Ship Building & Repairing (code NACE 35.1). The statistical data was supplied by GEP (the Office of Strategy & Planning of the Portuguese Ministry of Labour & Social Solidarity). The authors present and discuss a specific case study, in the shipyard’s technological area of surface treatment and protection, to demonstrate the method’s applicability and usefulness. 相似文献
158.
Rogier E. Hintzen Marina Papadopoulou Ross Mounce Cristina Banks-Leite Robert D. Holt Morena Mills Andrew T. Knight Armand M. Leroi James Rosindell 《Conservation biology》2020,34(3):721-732
Conservation biology was founded on the idea that efforts to save nature depend on a scientific understanding of how it works. It sought to apply ecological principles to conservation problems. We investigated whether the relationship between these fields has changed over time through machine reading the full texts of 32,000 research articles published in 16 ecology and conservation biology journals. We examined changes in research topics in both fields and how the fields have evolved from 2000 to 2014. As conservation biology matured, its focus shifted from ecology to social and political aspects of conservation. The 2 fields diverged and now occupy distinct niches in modern science. We hypothesize this pattern resulted from increasing recognition that social, economic, and political factors are critical for successful conservation and possibly from rising skepticism about the relevance of contemporary ecological theory to practical conservation. 相似文献
159.
Capozzi Fiore Sorrentino Maria Cristina Caporale Antonio Giandonato Fiorentino Nunzio Giordano Simonetta Spagnuolo Valeria 《Environmental science and pollution research international》2020,27(9):9075-9084
Environmental Science and Pollution Research - Metal uptake capacity and growth patterns of three cardoon cultivars (Sardo, Siciliano, and Spagnolo) were investigated for phytoremediation in a... 相似文献
160.
Amanda Lys dos Santos Silva Elane Cristina Loureno dos Santos Ana Maria Queijeiro Lpez 《Environmental science and pollution research international》2020,27(10):10275-10285
All processes in agro-industries consume water and generate large volumes of nutrient-rich effluents. To recycle effluents from a sugar–alcohol industry in the Northeastern Brazil (Coruripe, Alagoas), the effect of a daily application of a microbial formulation (containing five indigenous bacteria and two fungi), at the entrance of the two first facultative ponds (D, E) of its treatment plant formed by seven ponds (A–G), was evaluated in the sugarcane harvests of 2014/2015 and 2015/2016. Fortnightly, the values of 11 physicochemical parameters were checked and statistically compared (one and two-way ANOVA) in untreated (sedimentation pond A) and post-treated effluent (last facultative pond G), during both harvests. The treated effluent presented statistically significant improvements (p > 0.05), even between harvests, with averages of removal of organic matter of ca. 79.21% and 90.62%, and increases of the dissolved oxygen (DO) of ca. 72% and 74%, as well as the average increase of pH was ca. 42% and 50%. This better quality residue generally satisfied the class III level of the Brazilian Resolution 357/2005 (National Council for the Environment (CONAMA)), for water reuse in sugarcane irrigation on the yellow clay latosol soil, since it still is a light source of organic matter, nitrites and phosphorus, reducing the need of fertilizers for maintaining the productivity with low risk of salinization. According to Pearson’s bivariate correlation coefficient, while the DO and pH have positive correlation, they both have general inverse relation with the other physicochemical parameters evaluated and vice versa. 相似文献