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Physical Sciences and Mathematics Commons™
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Articles 1 - 6 of 6
Full-Text Articles in Physical Sciences and Mathematics
Variability In Population Abundance Is Associated With Thresholds Between Scaling Regimes, Donald Wardwell, Craig R. Allen
Variability In Population Abundance Is Associated With Thresholds Between Scaling Regimes, Donald Wardwell, Craig R. Allen
Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications
Discontinuous structure in landscapes may result in discontinuous, aggregated species bodymass patterns, reflecting the scales of structure available to animal communities within a landscape. The edges of these body-mass aggregations reflect transitions between available scales of landscape structure. Such transitions, or scale breaks, are theoretically associated with increased biological variability. We hypothesized that variability in population abundance is greater in animal species near the edge of bodymass aggregations than it is in species that are situated in the interior of body-mass aggregations. We tested this hypothesis by examining both temporal and spatial variability in the abundance of species in the …
A Neotropical Migrant Bird’S Dilemma— Where To Stop For A Good Meal, Joseph J. Fontaine, Charles Van Riper Iii
A Neotropical Migrant Bird’S Dilemma— Where To Stop For A Good Meal, Joseph J. Fontaine, Charles Van Riper Iii
Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications
To learn how migrating birds determine where to stop and find food, scientists from the U.S. Geological Survey, Northern Arizona University, and The University of Arizona studied the behavior of 28 species of neotropical migrant songbirds—warblers, flycatchers, tanagers, and vireos—along the lower Colorado River from 2001 to 2004. They found that, like interstate travelers greeted by restaurant billboards, songbirds flying over Cibola National Wildlife Refuge, Arizona, relied on the flowering of honey mesquite (Prosopis glandulosa) to detect the availability of insects that they prey on. Understanding where and why migrant birds stop will help land managers better protect …
Stomach Capacities Of Six Freshwater Fishes, Nathan J.C. Gosch, Kevin L. Pope, Paul H. Michaletz
Stomach Capacities Of Six Freshwater Fishes, Nathan J.C. Gosch, Kevin L. Pope, Paul H. Michaletz
Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications
We investigated the relationship between stomach capacity and total body length in bluegill (Lepomis macrocirirus), spotted bass (Microplerus punctulatus), white crappie (Pomoxis annularis), black crappie (Pomoxis nigromoculatus), channel catfish (Ictalurus punctatus) , and white bass (Morone chrysops). The rate of change in stomach capacity for a given change in fish length was greatest for spoiled bass and channel catfish, which may indicate greater ontogenetic shifts in feeding strategies. Fish with larger stomach capacities should have more plastic diets because they are capable of consuming a wider range of …
Seasonal Patterns Of Song Structure Variation In A Suboscine Passerine, Bruce A. Robertson, Joseph J. Fontaine, Elizabeth Loomis
Seasonal Patterns Of Song Structure Variation In A Suboscine Passerine, Bruce A. Robertson, Joseph J. Fontaine, Elizabeth Loomis
Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications
Studies of song and its function in suboscine passerines are rare. We examined spatial and temporal variation in song structure in a wild population of Olive-sided Flycatchers (Contopus cooperi) and tested among hypotheses explaining this variation. Repeatable variation in song type was observed both within and among individuals. More than 10% of territorial males expressed atypical song types, i.e., permutations of sequential missing and repeated elements of the typical adult song. Atypical songs were predominantly expressed by unpaired males independent of habitat type. A small fraction of males sang atypical song through the middle of the breeding season, …
Exploring Predation And Animal Coloration Through Outdoor Activity, Joseph J. Fontaine, Karie L. Decker
Exploring Predation And Animal Coloration Through Outdoor Activity, Joseph J. Fontaine, Karie L. Decker
Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications
Although children often characterize animals by the animals' color or pattern. the children seldom understand the evolutionary and ecological factors that favor particular colors. In this ilrticle. we describe two activities that help students understand the distinct evolutionary stmtegies of warning coloration and camoutlage. Because both of these strategies effectively allow prey animals to avoid predation. they can help explain considerable variation in animal coloration.
Spatial And Temporal Variation In Climate Change: A Bird’S Eye View, Joseph J. Fontaine, K. L. Decker, S. K. Skagen, C. Van Riper Iii
Spatial And Temporal Variation In Climate Change: A Bird’S Eye View, Joseph J. Fontaine, K. L. Decker, S. K. Skagen, C. Van Riper Iii
Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications
Recent changes in global climate have dramatically altered worldwide temperatures and the corresponding timing of seasonal climate conditions. Recognizing the degree to which species respond to changing climates is therefore an area of increasing conservation concern as species that are unable to respond face increased risk of extinction. Here we examine spatial and temporal heterogeneity in the rate of climate change across western North America and discuss the potential for conditions to arise that may limit the ability of western migratory birds to adapt to changing climates. Based on 52 years of climate data, we show that changes in temperature …