4,315 research outputs found
Code and data for "Within reach? Habitat availability as a function of individual mobility and spatial structuring"
No full textAn R project and associated code and data files covering the functions, illustrations, simulations and data analyses of the publication "Within reach? Habitat availability as a function of individual mobility and spatial structuring" by Matthiopoulos et al.</p
Code and data for "Within reach? Habitat availability as a function of individual mobility and spatial structuring"
No full text<p>An R project and associated code and data files covering the functions, illustrations, simulations and data analyses of the publication "Within reach? Habitat availability as a function of individual mobility and spatial structuring" by Matthiopoulos et al.</p>
Environmental constraints on the foraging behaviour, spatial usage and population sizes of albatrosses
No full textSatellite-tracking of wide-ranging, apex marine predators, combined with remote-sensing, can be used to test ecological hypotheses and to estimate spatial abundance. I
used this approach to quantify the habitat usage of central place foraging black-browed
albatrosses (BBA) from nine colonies, modelling population-level distribution as a
function of habitat accessibility, habitat preference and conspecific competition.
Throughout breeding, BBA preferred neritic waters, steeper bathymetry, and, during
incubation, warmer sea surface temperatures. BBA from South Georgia also preferred
highly dynamic oceanic waters. Foraging areas were partially spatially segregated with
respect to colony and region, presumably to reduce intraspecific competition. Although
such competition is often invoked to explain observed colony sizes, by accounting for
travel costs, I demonstrate a strong relationship between the sizes of regional
populations and the availability, accessibility and productivity of neritic waters,
supporting the hypothesis that seabird populations are constrained by breeding season
food availability. In response to this constraint, albatrosses have evolved to exploit
energetically efficient gliding flight, allowing them to access prey 100-1000s of km
from their colonies. Hence, I used satellite tracking and activity data to quantify the
effects of relative wind speed on the flight speed of four albatross species.
Groundspeed was linearly related to the wind speed in the direction of flight, its effect
being greatest on wandering albatrosses, followed by BBA, light-mantled and grey-
headed albatrosses, and airspeeds were higher in males than females. Commuting birds
tended to encounter headwinds during outward trips and tailwinds on their return, such
that return trips were faster. This supports the hypothesis that foraging upwind of the
colony is more efficient but could also result from wind climate and the relative
location of prey. The ability to use tracking data to estimate spatial usage is timely
given the acute threat currently posed to albatrosses by incidental fisheries mortality
Julia codes for "Communal and efficient movement routines can develop spontaneously through public information use", Behav Ecol.
No full textHere are provided all the Julia codes (v. 0.5.1) used to run the model presented
in: Riotte-Lambert, L. and J. Matthiopoulos. 2018. Communal and efficient movement routines can develop spontaneously through public information use. Behavioral Ecology.Use "exampleRun.jl" to run a simulation with default parameters.All details on the inputs and outputs of the functions are given as comments in the Julia scripts.</i
How to be a quantitative ecologist: the a to r of green mathematics and statistics/ Matthiopoulos
No full textxix, 467 hal.: ill.; tab.: 25 cm
Multi-species state-space modelling of the hen harrier (Circus cyaneus) and red grouse (Lagopus lagopus scoticus) in Scotland
No full textState-space modelling is a powerful tool to study ecological systems. The direct inclusion of uncertainty, unification of models and data, and ability to model unobserved, hidden states increases our knowledge about the environment and provides
new ecological insights. I extend the state-space framework to create multi-species
models, showing that the ability to model ecosystem interactions is limited only by data availability. State-space models are fit using both Bayesian and Frequentist methods, making them independent of a statistical school of thought. Bayesian approaches can have the advantage in their ability to account for missing data and fit hierarchical structures
and models with many parameters to limited data; often the case in ecological studies.
I have taken a Bayesian model fitting approach in this thesis.
The predator-prey interactions between the hen harrier (Circus cyaneus) and red grouse (Lagopus lagopus scoticus) are used to demonstrate state-space modelling’s
capabilities. The harrier data are believed to be known without error, while missing
data make the cyclic dynamics of the grouse harder to model. The grouse-harrier interactions are modelled in a multi-species state-space model, rather than including
one species as a covariate in the other’s model. Finally, models are included for the
harriers’ alternate prey.
The single- and multi-species state-space models for the predator-prey interactions
provide insight into the species’ management. The models investigate aspects of the species’ behaviour, from the mechanisms behind grouse cycles to what motivates harrier immigration. The inferences drawn from these models are applicable to management, suggesting actions to halt grouse cycles or mitigate the grouse-harrier conflict. Overall, the multi-species models suggest that two popular ideas for grouse-harrier management, diversionary feeding and habitat manipulation to reduce alternate prey densities, will not have the desired effect, and in the case of reducing prey densities, may even increase the harriers’ impact on grouse chicks
Jason Bond Family History
No full textJason Bond authored this family history as part of the course requirements for HIST 550/700 Your Family in History offered online in Fall 2017 and was submitted to the Pittsburg State University Digital Commons. Please contact the author directly with any questions or comments: [email protected]
Jason vs GIJOE
No full textThesis (Master's)--University of Washington, 2019Jason vs GI JOE is partly an exercise in autobiography, an experiment in relational aesthetics, and an interdisciplinary artist project at the intersection of comic books, creative writing and performance art. This comic book, Jason vs. GIJOE, is a postmodern double erasure, based on the comic book GIJOE: Cobra II (Issue 1). The original pictures from the comic book have been removed, and replaced by a series of short narratives, describing autobiographical events from the life of the author: me, Jason. Speech bubbles from the original have been left to comment back over top of the stories, obscuring meaning but creating moments of unplanned dialogue. The comic is a readymade, twice erased: once to replace the drawings of the initial comic, and again when using the original dialogue bubbles to speak back to the narrative
Oral history interview with Jason Poudrier
No full textJason Poudrier, author, discusses growing up in a military family and living in Alaska, North Dakota, Oregon, and finally Oklahoma. He describes what it was like enlisting in the Army after high school in 2001 and how his military service affected him. A recipient of the Purple Heart, he shares his experiences getting injured by shrapnel in Iraq. He later talks about how he uses poetry and writing to cope with his memories of war, and how he hopes to help others do the same.The Deep Roots: Oklahoma Authors Collection is a series of interviews with authors who discuss their lives, work, and creative processes
R Code and Output Supporting: Used-habitat calibration plots: A new procedure for validating species distribution, resource selection, and step-selection models
No full textEach example.html file (“example_”) uses various uhcplot functions (html files with description “code for function”). The example with the MN moose data (example_4_moose.html) also uses data for one Minnesota moose from 2013 and 2014 (in moose12687.csv). The tables (tables.html) are created with regression output files created and saved with the codes provided in the example.html files. The zipped folder (UHCPlotsPaper_R.zip) contains all of the Program R files (.R extension) for each of the html files. MNmoose_Arrowhead.pdf details the location of the moose from dataset. See the readme.txt for more information.Species distribution models (SDMs) are one of a variety of statistical methods that link individuals, populations, and species to the habitats they occupy. In Fieberg et al. "Used-habitat calibration plots: A new procedure for validating species distribution, resource selection, and step-selection models", we introduce a new method for model calibration, which we call Used-Habitat Calibration plots (UHC plots) that can be applied across the entire spectrum of SDMs. Here, we share the Program R code and data necessary to replicate all three of the examples from the manuscript that together demonstrate how UHC plots can help with three fundamental challenges of habitat modeling: identifying missing covariates, non-linearity, and multicollinearity.This work was funded in part by the University of Minnesota-Twin Cities and the Minnesota Environment and Natural Resources Trust Fund. The Minnesota Department of Natural Resources assisted with collaring and monitoring of the moose.Fieberg, John R; Forester, James D; Street, Garrett M; Johnson, Douglas H; ArchMiller, Althea A; Matthiopoulos, Jason. (2016). R Code and Output Supporting: Used-habitat calibration plots: A new procedure for validating species distribution, resource selection, and step-selection models. Retrieved from the University Digital Conservancy, http://doi.org/10.13020/D6T590
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