Shifts in Microbial Communities,Microbial Biomass and Organic Matter Mineralization for Three Mediterranean Soils Contaminated By Metals

Microbial communities (phospholipid fatty acid pattern, bacterial growing strategies, eco-physiological index (EPI) and total bacteria counts, as a number of heterotrophic cuhurable bacteria), substrate-induced respiration (SIR), and nitrogen mineralization were studied in three Mediterranean soils at three different depth levels (A, B and C). Soils were experimentally treated with a final concentration of 1000 ppm of trace metals (Cu²⁺, Zn²⁺, Al³⁺, Fe²⁺, Pb²⁺, Ni²⁺, Mn²⁺, Cr³⁺ and Cd²⁺). Soils were stored in 571 plastic containers for one year, and watered with 1001 during this period. Leachate was recovered through a bottom tap. Samples of the three depths were studied. Soil microbial communities showed different effects to other studies presented in the literature, but carried out on non-Mediterranean soils. Dramatic differences were found between treated soils and untreated ones, but not between soils or horizons. the treated soil displayed a decrease in CFUs, SIR N-mineralization and EPI together with a dominance of r-growing strategists. the relative moles percent of several PLFAs, especially 15:0, 16: 1ω7, cy17: 0, br18:0 and 18: 1ω7 decreased because of the pollution of soils, whereas 10Me16, 18:2ω6, cy19:0, i16:0 and br17:0 showed higher values than in untreated soils.     

Heavy Metals in Macroalgae of Havana's Northern Littoral,Cuba

Copper, iron, lead, manganese, and zinc contents were determined in various phyla of macroalgae typical of the rocky mesolittoral zone of Cuba and widely distributed in the Caribbean Region. the samples were collected in different zones along the shores of Havana City which are more or less influenced by anthropogenic activities. Differences in metal contents were observed due to seasonal variations and differences between sampling sites. of the analyzed species, only one brown alga, Padina vickersiae is considered as a suitable candidate for the monitoring of metal contamination.     

Spatial variogram estimation from temporally aggregated seabird count data

Seabird abundance is an important indicator for assessing impact of human activities on the marine environment. However, data collection at sea is time consuming and surveys are carried out over several consecutive days for efficiency reasons. This study investigates the validity of aggregating those data over time to estimate a spatial variogram that is representative for spatial correlation in species abundance. For this purpose we simulate four-day surveys of seabird count data that contain spatial and temporal correlation arising from temporal changes in the spatial pattern of environmental conditions. Estimates of the aggregated spatial variogram are compared to a variogram that would arise when data were collected over a single day. The study reveals that, under changing environmental conditions over surveys days, aggregating data over a four-day survey increases both the non-spatial variation in the data and the scale of spatial correlation in seabird data. Next, the effect of using an aggregated variogram on the statistical power to test the significance of an impact is investigated. The impact concerns a case of establishing an offshore wind farm resulting in seabird displacement. The study shows that both overestimation and underestimation of statistical power occurs, with power estimates differing up to a factor of two. We conclude that the spatial variation in seabird abundance can be misrepresented by using temporally aggregated data. In impact studies, such misrepresentation can lead to erroneous assessments of the ability to detect impact.     

Individual differences in sampling behaviour predict social information use in zebra finches

When animals have to decide where to forage, what to eat or with whom to mate, they can base their decisions on either socially or personally acquired information. In accordance with theoretical predictions, there is experimental evidence that animals adjust the weight they give to both sources of information depending on circumstances. Notably, several studies have demonstrated that individuals rely more on social information when personal information is difficult to acquire or unreliable, because these conditions leave them uncertain as how to behave. Yet, even when individuals are exposed to the same conditions, they generally differ widely in the value they attribute to social and personal information. These differences suggest that the tendency to rely on social information would also depend on intrinsic characteristics that affect, for instance, individual efficiency in collecting personal information. To address this issue, we conducted laboratory experiments using female zebra finches (Taeniopygia guttata) and we tested them under three consecutive conditions. First, we evaluated their reliance on social information in a mating context and in a foraging context. Then, we measured their efficiency in acquiring personal information by recording their sampling behaviour when searching for hidden food. We found that females that sampled their environment less actively consistently relied on social information to a greater extent compared with those that invested more in sampling. Contrary to what is generally assumed, then, our study demonstrates that social information use is not entirely flexible and context dependent.     

Persistent bimodal activity patterns in wild and captive black-tailed godwit <Emphasis Type="Italic">Limosa limosa</Emphasis> under different environmental conditions

There is a large literature dealing with daily foraging routines of wild birds during the non-breeding season. While different laboratory studies have showed that some bird activity patterns are a persistent property of the circadian system, most of field studies preclude the potential role of an endogenous circadian rhythm in controlling bird’s foraging routines. In this study we compared the patterns of diurnal foraging activity and intake rates of migrating black-tailed godwits, Limosa limosa (radio-tagged and non-tagged individuals) at two stopover sites (habitats) with different environmental characteristics, aiming at identifying proximate factors of bird activity routines. To gain insights into the role of food availability in control of such foraging routines, we also estimated foraging activity patterns in captive godwits subjected to constant food availability. Captive and wild black-tailed godwits showed a persistent bimodal activity pattern through daylight period. Food availability had a significant effect on the intake rates, but had a subtler effect on foraging and intake rate rhythms. Temperature and wind speed (combined in a weather index) showed non-significant effects on both rhythms. Although we could not discard a role for natural diurnal changes in light intensity, an important timing cue, our findings support the idea that an endogenous circadian rhythm could be an important proximate factor regulating foraging activity and food items taken per unit time of wild black-tailed godwits during migration.     

A case for quantile regression in behavioral ecology: getting more out of flight initiation distance data

A central goal of behavioral ecology is to quantify and explain variation in behavior. While much previous work has focused on the differences in mean behavior across groups or treatments, we present a complementary approach studying changes in the distribution of the response variable. This is important because changes in the edges of a distribution may be more informative than changes in the mean if behavior at the edges of a distribution better reflects behavioral constraints. Quantile regression estimates the rate of change of conditional quantiles of a response variable and thus allows the study of changes in any part of its distribution. Although quantile regression is gaining popularity in the ecological literature, it is strikingly unused in behavioral ecology. Here, we demonstrate the usefulness of this method by analyzing the relationship between the starting distance (SD) at which an observer approach a focal animal and its flight initiation distance (FID, the distance between the observer and the animal when it decides to flee). In particular, we used a simple model of flight initiation distance to show that in most situations ordinary least-square regression cannot be used to analyse the SD–FID relationship. Quantile regression conducted on the lowest quantiles appears more robust and we applied this approach to data from four bird species. Overall, changes in the lowest FID values appeared to be the most informative to determine if a species displays a “flush early” strategy, a strategy which has been hypothesized to be a general rule. We hope this example will bring quantile regression to the attention of behavioral ecologists as a valuable tool to add to their statistical toolbox.     

Design solutions to coastal human-wildlife conflicts

Coastal areas can be a challenge for conservation due to multiple competing land uses including development, tourism, and extractive resource use. These multiple land uses often lead to human-wildlife conflicts. Here we propose that collaboration with industrial designers and architects has the potential to generate innovative and effective solutions to coastal human-wildlife conflicts. Many products for modifying animal behavior are already used by conservationists, such as barriers, corridors, and model predators. We propose that their effectiveness, quality, harmonization with local values, and integration with the designed human environment can be improved through collaboration with designers and architects. We illustrate this approach with a case study. We engaged in an industrial design- conservation collaboration focused on the design of multiple product proposals that would support a range of human-sea lion interactions in public parks and the fish market in Valdivia, Chile. The sea lions in Valdivia are a tourist attraction but also potentially dangerous. We produced images of seven proposed products of varying scales, facilitating a range of different sea lion- human interactions. Such collaborations can be useful for developing products that reduce human-wildlife conflicts and align conservation and management with local values. We urge researchers to publish conservation design proposals as well as tests of existing conservation products?? functionality, in order to improve conservation design practice around the world.     

The interaction between reproductive cost and individual quality is mediated by oceanic conditions in a long-lived bird

Environmental variability, costs of reproduction, and heterogeneity in individual quality are three important sources of the temporal and interindividual variations in vital rates of wild populations. Based on an 18-year monitoring of an endangered, recently described, long-lived seabird, Monteiro's Storm-Petrel (Oceanodroma monteiroi), we designed multistate survival models to separate the effects of the reproductive cost (breeders vs. nonbreeders) and individual quality (successful vs. unsuccessful breeders) in relation to temporally variable demographic and oceanographic properties. The analysis revealed a gradient of individual quality from nonbreeders, to unsuccessful breeders, to successful breeders. The survival rates of unsuccessful breeders (0.90 +/- 0.023, mean +/- SE) tended to decrease in years of high average breeding success and were more sensitive to oceanographic variation than those of both (high-quality) successful breeders (0.97 +/- 0.015) and (low-quality) nonbreeders (0.83 +/- 0.028). Overall, our results indicate that reproductive costs act on individuals of intermediate quality and are mediated by environmental harshness.     

Evolution, radiation and chemotaxonomy of Lamellodysidea, a demosponge genus with anti-plasmodial metabolites

Sponges of the family Dysideidae (Dictyoceratida) are renowned for their diversity of secondary metabolites, and its genus Lamellodysidea, particularly Lamellodysidea herbacea, is the most studied taxon biochemically. Despite its importance, the taxonomic status of L. herbacea—whether it is a distinct species or a species complex—has never been assessed. Recent biochemical profiling revealed anti-plasmodial activity of brominated compounds in Lamellodysidea of the Pacific. Here, we present a comparative chemotaxonomic and molecular analysis of selected Dysideidae from the Pacific and the Indian Ocean (New Caledonia, Great Barrier Reef, Fiji, Mayotte, Guam, Palau). We investigated the phylogenetic relationships between the populations and assessed their bioactive (PBDE) compounds in order to unravel the taxonomic status of this commercially important group of sponges and assessed patterns of dispersal and biochemical variation. The molecular phylogeny was based on the internal transcribed ribosomal spacer and compared against a PBDE phylogeny for several specimens. Molecular data revealed a diversity of Indo-Pacific L. herbacea populations, also reflected by different PBDE compound profiles. Molecular and biochemical data also revealed a Lamellodysidea species new to science. Several specimens misidentified as Lamellodysidea were detected based on their position on different clades in the molecular phylogeny and their production of different halogenated compounds (brominated vs. chlorinated). The direct comparison of molecular and biochemical data also provided evidence for the occurrence of a host switch event and support for the theory that abiotic factors, such as sedimentation, affect the chemical constituents produced in L. herbacea.     

Multi-scale foraging variability in Northern gannet (Morus bassanus) fuels potential foraging plasticity

The survival of marine predators depends on behavioural plasticity to cope with changes in prey distribution. Variability in behaviour might predict plasticity and is easier to assess than plasticity. Using miniaturized GPS loggers over several breeding seasons in two Norwegian Northern gannet (Morus bassanus) colonies, we investigated if and how the variability within and between individuals, but also between colonies and years, affected foraging strategies. Results revealed strong individual variability (foraging trip durations, foraging effort and different foraging areas). Individuals from both colonies showed preferred commuting routes, flight bearings and feeding hotspots. Individuals from the largest colony used larger and more foraging areas than individuals from the small colony. Feeding hotspots and foraging ranges varied amongst years in the largest colony only. Our study demonstrated that gannets show flexibility by changing prey fields that are driven by shifting oceanographic conditions.