Short- and long-term consistency in the foraging niche of wandering albatrosses

The wandering albatross (Diomedea exulans) is regarded as a generalist predator, but can it be consistent in its foraging niche at an individual level? This study tested short- and long-term consistency in the foraging niche in terms of habitat use, trophic level and, by inference, prey selection. Fieldwork was carried out at Bird Island, South Georgia, in May–October 2009, during the chick-rearing period. Blood (plasma and cells) and feathers for stable isotope analyses (δ¹³C and δ¹⁵N) were sampled from 35 adults on their return from a foraging trip during which they carried stomach temperature, activity and global positioning system loggers. Results suggest short-term consistency in foraging niche in relation to both oceanic water mass and trophic level, and long-term consistency in use of habitat. Consistent differences between individuals partly reflected sex-specific habitat preferences. The proportion of consistent individuals (i.e., with a narrow foraging niche) was estimated at c. 40?% for short-term habitat and trophic level (prey) preferences and 29?% for longer-term habitat preference, suggesting this is an important characteristic of this population and potentially of pelagic seabirds in general. Foraging consistency was not related to body condition or level of breeding experience; instead, it may reduce intraspecific competition.     

Using carbon and nitrogen isotopic values of body feathers to infer inter- and intra-individual variations of seabird feeding ecology during moult

To determine whether stable isotope measurements of body feathers can be used to investigate the isotopic niche of moulting (inter-nesting) adult seabirds, we examined the stable carbon (δ¹³C) and nitrogen (δ¹⁵N) isotopic composition of body feathers of breeding wandering albatrosses (Diomedea exulans) from Crozet Islands, southern Indian Ocean. First we showed that the isotopic composition of body feathers was not significantly different from that of wing feathers, being thus a safe alternative to flight feathers whose collection impairs the birds’ flying ability. Second, we looked at the variances in δ¹³C and δ¹⁵N values resulting from the isotopic measurement of a single feather, four different feathers, and a pool of four feathers per bird, to delineate the best isotopic analytical procedure. A two-step protocol is proposed that allows investigating both the intra- and inter-individual components of the niche width of the species. In a first step, isotopic measurements on a single feather per bird are used to define isotopic specialist from isotopic generalist populations. In a second step and for generalist populations only, measurements on additional (three) feathers per bird are used to delineate type A from type B isotopic generalists (Bearhop et al. in J Anim Ecol 73:1007–1012, 2004). Third, from a biological point of view, our data showed different moulting isotopic niches for adult males and females, and also within female wandering albatrosses. Since the isotopic composition of body feathers in this species reflects that of wing feathers, our results suggest that, after validation, body feathers have the potential for investigating the foraging ecology of other Procellariiforms and seabirds during the poorly known inter-nesting period.     

Differences in δ13C and δ15N values between feathers and blood of seabird chicks: implications for non-invasive isotopic investigations

Blood and feathers are the most targeted tissues for isotopic investigations in avian ecology, primarily because they can be easily and non-destructively sampled on live individuals. Comparing blood and feather isotopic ratios can provide valuable information on dietary shifts, trophic specialization and migration patterns, but it requires a good knowledge of the isotopic differences between the two tissues. Here, δ¹³C and δ¹⁵N values of whole blood (in blood cells of a few species) and simultaneously grown body feathers were measured in seabird chicks to quantify the tissue-related isotopic differences. Seabirds include 27 populations of 22 wild species that were sampled in 2000–2008, and a review of the literature added 8 groups (including adult birds) to the analysis. The use of a large data set that overall encompasses wide δ¹³C and δ¹⁵N ranges allowed us to depict for the first time accurate relationships between blood and feather isotopic ratios across avian taxa. Blood was impoverished in ¹³C and generally in ¹⁵N compared with feathers. Both mean δ¹³C and δ¹⁵N values of feathers and blood were highly positively and linearly related [feather δ¹³C = 0.972 (±0.020) blood δ¹³C + 0.962 (±0.414), and feather δ¹⁵N = 1.014 (±0.056) blood + 0.447 (±0.665), respectively; both P < 0.0001]. The regressions should be applied to mathematically correct feather or whole blood δ¹³C and δ¹⁵N values when comparing isotopic ratios within and between ecological studies on birds.     

Moulting patterns drive within-individual variations of stable isotopes and mercury in seabird body feathers: implications for monitoring of the marine environment

One major limitation in the use of body feathers of seabirds as a monitoring tool of the trophic structure and contamination levels of marine ecosystems is the degree of heterogeneity in feather chemical composition within individuals. Here, we tested the hypothesis that moulting patterns drive body feather heterogeneity, with synchronous moult minimizing within-individual variations, in contrast to asynchronous feather growth. Chicks of white-chinned petrels Procellaria aequinoctialis (representative of bird chicks) and adults of king penguins Aptenodytes patagonicus (representative of adult penguins) that moult their body feathers synchronously showed very low within-individual variations in their feather δ¹³C and δ¹⁵N values and mercury (Hg) concentrations. By contrast, body feathers of adults of Antarctic prions Pachyptila desolata (representative of adult seabirds with asynchronous feather growth during a protracted moult) presented much higher within-individual variances for the three parameters. These findings have three important implications for birds presenting a synchronous body moult. (1) They suggest that all body feathers from the same individual have identical δ¹³C and δ¹⁵N values and Hg content. (2) They predict negligible within-individual variations in the body feather values of other useful stable isotopes, such as δ²H and δ³⁴S, as well as in the concentrations of other compounds that are deposited in the keratin structure. (3) Analysis of one or any number of pooled body feathers is equally representative of the individual. In conclusion, we recommend that long-term routine monitoring investigations focus on birds presenting synchronous rather than asynchronous moult of body feathers both in marine and terrestrial environments. This means targeting chicks rather than adults and, for seabirds, penguins rather than adults of flying species.     

Facilitating biodiversity conservation through partnerships to achieve transformative outcomes

Conservation biology is a mission-driven discipline that must navigate a new relationship between conservation and science. Because conservation is a social and political as well as an ecological project, conservation biologists must practice interdisciplinarity and collaboration. In a comparative study of 7 cases (Jaguars in the Chaco, Grevy's zebra in Kenya, Beekeeping in Tanzania, Andean cats in Argentina, Jaguars in Mexico, Lobster fishing, and Black bears in Mexico), we examined motivations for collaboration in conservation, who can collaborate in conservation, and how conservation professionals can work well together. In 5 case studies, successful conservation outcomes were prioritized over livelihood benefits. In the other 2 cases, livelihoods were prioritized. All case studies employed participatory approaches. There were multiple external actors, including local and Indigenous communities, nongovernmental organizations, agencies, regional and national governments, and international organizations, which enhanced conservation and wider sustainability outcomes. Key collaboration aspects considered across the case studies were time (mismatch between relationship building and project schedules), trust required for meaningful partnerships, tools employed, and transformative potential for people, nature, and the discipline of conservation biology. We developed guidelines for successful collaboration, including long-term commitment, knowledge integration, multiscalar and plural approaches, cultivation of trust, appropriate engagement, evaluation, supporting students, and efforts for transformation.     

兰州市西固区土壤中PAHs污染特征及来源解析

为了解石油工业区土壤中PAHs(多环芳烃)的污染特征、来源及潜在危害,选择兰州市西固区为研究区域,系统采集表层土壤样品及部分剖面样品,采用GC-MS检测方法,分析了土壤中PAHs的污染水平与分布、来源及潜在致癌风险. 结果表明:研究区表层(0~20 cm)土壤中w(∑PAHs)(22种PAHs的总质量分数)在535～32 300 μg/kg之间;PAHs在土壤剖面的纵向分布上主要集中在5～10 cm,在0～25 cm范围内变化不明显;表层土壤中PAHs主要以2～3环为主. 相关性分析显示,土壤中w(∑PAHs)与w(TOC)无显著的相关性,表明TOC并非影响土壤中PAHs持留的重要因素. 研究区土壤中PAHs主要来源于石油、生物质和煤炭的燃烧,∑TEQ_BaP (22种PAHs的毒性当量浓度,以苯并芘等效浓度计)平均值为190 μg/kg,表明土壤中PAHs的潜在致癌性较低.      

Effects of a major municipal effluent on the St. Lawrence River: A case study

The St. Lawrence River (SLR) is the second largest waterway in North America. The discharge of the City of Montreal wastewater treatment plant (WWTP) represents the largest volume of treated wastewaters being released into the river. It also ranks as the largest sewage treatment plant of its kind in North America. Over the last decade, intensive multidisciplinary research has focused on assessing the impacts of Montreal wastewater effluents on the SLR. We describe the major findings of these investigations, including the determination of the fate of contaminants, bioaccumulation in fish and invertebrates, ecotoxicological measurements of aquatic animal health, evaluation of endocrine disruption, parasitism in fish, and combined effects of multiple stressors on the SLR. Impacts of the effluents from the WWTP on aquatic organisms from the SLR are both toxicological and ecological, demonstrating the need for an integrated view of the impacts of municipal effluents on aquatic ecosystems.     

Prenatal diagnosis of mucolipidosis type II on first-trimester amniotic fluid

We investigated the possibility of prenatal diagnosis of mucolipidosis type II (ML II) by lysosomal enzyme determination on amniotic fluid obtained at 11 weeks of gestation in three pregnancies at risk. Diagnosis of ML II was made in one case on the basis of increased levels of five lysosomal enzymes tested. The diagnosis was confirmed on cultured chorionic cells, their cultured medium, 17–week amniotic fluid, and fetal plasma obtained for confirmation prior to the termination of pregnancy.