Environmental enrichment for zoo bears

The high incidence of stereotypic behaviors in zoo bears (van Keulen-Kromhout: International Zoo Yearbook 18:177–186, 1978) suggests that the environment of these animals lacks essential stimuli for guiding normal behavior. Three experiments investigated ways in which bear husbandry procedures can be altered to promote normal behavior. In experiments 1 and 2, honey-filled logs were given to a sloth (Melursus ursinus), American black (Ursus americanus), and brown bear (Ursus arctos) to determine 1) the role of food in stimulating investigatory behavior, 2) the rate of habituation to manipulable objects introduced into the exhibit, and 3) effects on locomotory behaviors. Results show specific and general habituation to the introduced objects that can be counteracted by refilling the logs with honey and by providing multiple logs in the exhibit. Investigatory activity directed toward honey-logs replaces pacing and walking in the sloth bear and is most effective in doing so when the log is novel. Experiment 3 examined the behavioral effects of feeding an American black bear in three different ways: 1) once daily in the den, 2) once daily with supplemental food from a mechanical feeder, and 3) once daily with food hidden in the exhibit in manipulatable objects. The latter method reduced stereotypic pacing from a median of 150 min/day to 20 min/day; the mechanical feeder method had no such effect. The results of a survey of 67 zoos concerning the diet and manner of feeding these three species of bears, as well as Asian black bears (Ursus thibetanus) are presented. Results are discussed with respect to the ways in which husbandry procedures can be improved to stimulate functional foraging and feeding behavior in confined bears.     

Environmentally Conscious Product Design: A Collaborative Internet-based Modeling Approach

This paper proposes a computer-based method for providing product designers with real-time environmental impact assessment. In this concurrent modeling approach, environmental experts build life-cycle models, define their interfaces, and publish them as distributed objects on the Internet. Traditional designers integrating these objects into their design models have access to the impact assessment methods provided by the environmental expert. In this paradigm, the focus shifts from providing techniques that let non-expert designers perform life-cycle impact assessments to tools that facilitate timely communication and information transfer between designers and appropriate environmental experts. Establishing real-time communication between the product design models and the environmental life-cycle models is the primary focus of this paper. Methods for establishing and maintaining the interaction between life-cycle and product design models are described. A beverage container design example illustrates how this collaborative approach can use environmental and traditional design goals to determine effective tradeoffs between design alternatives.     

Embedding Science in Politics: "Complex Utilization" and Industrial Ecology as Models of Natural Resource Use

Throughout the short history of industrial ecology, issues of implementation have been heavily emphasized. Less attention has been given to the ways in which the technical models of industrial ecology interact with social processes. Yet the practitioners of industrial ecology frequently encounter challenges pertaining to contextualization when embedding a general model in different local contexts. In addition, there are reasons to believe that the models of industrial ecological systems become politically meaningful only when they are carefully contextualized and linked to localized needs. In this article, we aim at a better understanding of the political embedding of industrial ecology. In order to demonstrate some general mechanisms of embedding, we first conduct a frame analysis of complex utilization—a scientific policy instrument analogous to industrial ecology, developed in the Kola Peninsula, Russia. We identify five frames in which complex utilization has been promoted between 1935 and 2005. These frames are then compared to six frames identified in the industrial symbiosis in Kalundborg, Denmark. We find that effective political embedding relies on frames that function both on a general level and in specific contexts. General frames, such as efficiency, economy, and environment, need to be aligned with localized perceptions of particular issues. What is more, sensitivity to purely context-specific frames is necessary for effective political embedding. Finally, the political processes of framing also shape the scientific-technical models that are being promoted.     

Different nest predator faunas and nest predation risk on ground and shrub nests at forest ecotones: an experiment and a review

This study examined predator faunas of artificial ground and shrub nests and whether nest predation risk was influenced by nest site, proximity to forest edge, and habitat structure in 38 grassland plots in south-central Sweden. There was a clear separation of predator faunas between shrub and ground nests as identified from marks in plasticine eggs. Corvids accounted for almost all predation on shrub nests whereas mammals mainly depredated ground nests. Nest predation risk was significantly greater for shrub than for ground nests at all distances (i.e. 0, 15 and 30 m) from the forest edge. However, nest predation risk was not significantly related to distance to forest edge, but significantly increased with decreasing distance to the nearest tree. Different corvid species robbed nests at different distances from the forest edge, with jays robbing nests closest to edges. We conclude that the relationship between the predation risk of grassland bird nests and distance to the forest edge mainly depends on the relative importance of different nest predator species and on the structure of the forest edge zone. A review of published articles on artificial shrub and ground nest predation in the temperate zone corroborated the results of our own study, namely that shrub nests experienced higher rates of depredation in open habitats close to the forest edge and that avian predators predominantly robbed shrub nests. Furthermore, the review results showed that predation rates on nests in general are highest <50 m inside the forest and lower in open as well as forest interior habitats (≥50 m from the edge). Received: 16 March 1998 / Accepted: 30 July 1998     

Visual Ecology and Perception of Coloration Patterns by Domestic Chicks

This article suggests how we might understand the way potential predators see coloration patterns used in aposematism and visual mimicry. We start by briefly reviewing work on evolutionary function of eyes and neural mechanisms of vision. Often mechanisms used for achromatic vision are accurately modeled as adaptations for detection and recognition of the generality of optical stimuli, rather than specific stimuli such as biological signals. Colour vision is less well understood, but for photoreceptor spectral sensitivities of birds and hymenopterans there is no evidence for adaptations to species-specific stimuli, such as those of food or mates. Turning to experimental work, we investigate how achromatic and chromatic stimuli are used for object recognition by foraging domestic chicks (Gallus gallus). Chicks use chromatic and achromatic signals in different ways: discrimination of large targets uses (chromatic) colour differences, and chicks remember chromatic signals accurately. However, detection of small targets, and discrimination of visual textures requires achromatic contrast. The different roles of chromatic and achromatic information probably reflect their utility for object recognition in nature. Achromatic (intensity) variation exceeds chromatic variation, and hence is more informative about change in reflectance – for example, object borders, while chromatic signals yield more information about surface reflectance (object colour) under variable illumination. This revised version was published online in July 2006 with corrections to the Cover Date.     

A Comparative Study on the Power of van Lieshout and Baddeley's J-Function

Summary functions such as the empty space function F and the nearest neighbour distance distribution function G are often used as test statistics for point patterns. Van Lieshout and Baddeley recently proposed an alternative statistic, the J-function, which is defined as J = (1 — G)/(1 — F). Theoretical advantages of the J-function over the F- and G-statistics are that it measures the type, strength and range of interaction, and that it can be evaluated explicitly for a larger class of models. In this simulation study we investigate empirically how the power of tests based on J compares to that of tests based on F and G.     

Cracking the nut: geographical adjacency of sister taxa supports vicariance in a polytomic salamander clade in the absence of node support

The urodelan genus Lyciasalamandra, which inhabits a relatively small area along the southern Turkish coast and some Aegean islands, provides an outstanding example of a diverse but phylogenetically unresolved taxon. Molecular trees contain a single basal polytomy that could be either soft or hard. We here use the information of nuclear (allozymes) and mitochondrial (fractions of the 16S rRNA and ATPase genes) datasets in combination with area relationships of lineages to resolve the phylogenetic relationships among Lyciasalamandra species in the absence of sufficient node support. We can show that neither random processes nor introgressive hybridization can be invoked to explain that the majority of pairs of sister taxa form geographically adjacent units and interpret that this pattern has been shaped by vicariant events. Topology discordance between mitochondrial and nuclear trees mainly refers to an affiliation of L. helverseni, a taxon restricted to the Karpathos archipelago, to the western-most and geographically proximate mainland taxon in the nuclear tree, while in the organelle tree it turns out to be the sister lineage to the geographically most distant eastern clade. As this discordance cannot be explained by long-branch attraction in either dataset we suppose that oversea dispersal may have accounted for a second colonization of the Karpathos archipelago. It may have initiated introgression and selection driven manifestation of alien eastern mitochondrial genomes on a western nuclear background. Our approach of testing for area relationships of sister taxa against the null hypothesis of random distribution of these taxa seems to be especially helpful in phylogenetic studies where traditional measures of phylogenetic branch support fail to reject the null hypothesis of a hard polytomy.