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These publications showcase the significant science conducted in our Science Centers.

Filter Total Items: 16731

Individual foraging strategies of kleptoparasitic Roseate Terns Individual foraging strategies of kleptoparasitic Roseate Terns

We describe the kleptoparasitic behavior of ten adult Roseate Terns (Sterna dougallii) breeding at a colony at Falkner Island, Connecticut, USA between 1995 and 1998. These birds were considered habitual kleptoparasites because they stole fish repeatedly from other terns in every year they were observed at the site. No other breeding individuals were observed attempting to steal fish...
Authors
D. A. Shealer, Jeffrey A. Spendelow

Schizochromism in a Peregrine Falcon from Arizona Schizochromism in a Peregrine Falcon from Arizona

Herein, we report the first record of schizochromism in the Peregrine Falcon (Falco peregrinus). Our example is a nestling from southern Arizona. The lack of dark brown pigment in this bird made it closely resemble the blue-gray plumage of an adult. Near fledging time, the bird was eaten by its nestmates, so this article also documents cannibalism.
Authors
D. H. Ellis, L.W. Oliphant, J.K. Fackler

Narrowing historical uncertainty: probabilistic classification of ambiguously identified tree species in historical forest survey data Narrowing historical uncertainty: probabilistic classification of ambiguously identified tree species in historical forest survey data

Historical data have increasingly become appreciated for insight into the past conditions of ecosystems. Uses of such data include assessing the extent of ecosystem change; deriving ecological baselines for management, restoration, and modeling; and assessing the importance of past conditions on the composition and function of current systems. One historical data set of this type is the...
Authors
D.J. Mladenoff, S.E. Dahir, E.V. Nordheim, L.A. Schulte, G.R. Guntenspergen

Management practices that concentrate visitor activities: Camping impact management at Isle Royale National Park, USA Management practices that concentrate visitor activities: Camping impact management at Isle Royale National Park, USA

This study assessed campsite conditions and the effectiveness of campsite impact management strategies at Isle Royale National Park, USA. Protocols for assessing indicators of vegetation and soil conditions were developed and applied to 156 campsites and 88 shelters within 36 backcountry campgrounds. The average site was 68 m2 and 83% of sites lost vegetation over areas less than 47 m2...
Authors
Jeffrey L. Marion, T. A. Farrell

Occam's shadow: levels of analysis in evolutionary ecology - where to next? Occam's shadow: levels of analysis in evolutionary ecology - where to next?

Evolutionary ecology is the study of evolutionary processes, and the ecological conditions that influence them. A fundamental paradigm underlying the study of evolution is natural selection. Although there are a variety of operational definitions for natural selection in the literature, perhaps the most general one is that which characterizes selection as the process whereby heritable...
Authors
E.G. Cooch, E. Cam, W.A. Link

Ecological and evolutionary traps Ecological and evolutionary traps

Organisms often rely on environmental cues to make behavioral and life-history decisions. However, in environments that have been altered suddenly by humans, formerly reliable cues might no longer be associated with adaptive outcomes. In such cases, organisms can become 'trapped' by their evolutionary responses to the cues and experience reduced survival or reproduction. Ecological traps...
Authors
Martin A. Schlaepfer, M.C. Runge, P. W. Sherman

Baseline hematology and clinical chemistry results from captive-raised trumpeter swans Baseline hematology and clinical chemistry results from captive-raised trumpeter swans

Results from hematology and clinical chemistry tests are presented for healthy captive-raised Trumpeter Swans (Cygnus buccinator) to help establish baseline data. Blood samples were obtained from 14 cygnets between the ages of three to four and seven to eight months that were the subjects of a study to teach migration routes to swans. Males and females differed significantly in...
Authors
Glenn H. Olsen, D.L. Rininger, M.K. Ets, William J.L. Sladen

Visitor impact assessment and monitoring systems: Evolution and current development Visitor impact assessment and monitoring systems: Evolution and current development

Managers of protected areas are increasingly concerned with recreation impacts to the resource and how they should be managed. Impact management programs must be based on information about the severity and extent of impacts and how they are changing over time. This information need has generated considerable interest in the development of visitor impact assessment and monitoring (VIAM)...
Authors
Y.-F. Leung, J. L. Marion, D.N. Cole

Statistical concepts: Estimating absolute densities of tigers using capture-recapture sampling Statistical concepts: Estimating absolute densities of tigers using capture-recapture sampling

Contents: -- Introduction -- Photo trapping tigers -- Capture-recapture models -- Survey design considerations -- Conclusion -- References
Authors
J.D. Nichols, K. U. Karanth
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