Tracking native small mammals to measure fine-scale space use in grazed and restored dry woodlands

Longer-range movements of anuran amphibians such as mass migrations and habitat invasion have received a lot of attention, but fine-scale spatial behavior remains largely understudied. This gap is especially striking for species that show long-term site fidelity and display their whole behavioral repertoire in a small area. Studying fine-scale movement with conventional capture-mark-recapture techniques is difficult in inconspicuous amphibians: individuals are hard to find, repeated captures might affect their behavior and the number of data points is too low to allow a detailed interpretation of individual space use and time budgeting. In this study, we overcame these limitations by equipping females of the Brilliant-Thighed Poison Frog (Allobates femoralis) with a tag allowing frequent monitoring of their location and behavior. Neotropical poison frogs are well known for their complex behavior and diverse reproductive and parental care strategies. Although the ecology and behavior of the polygamous leaf-litter frog Allobates femoralis is well studied, little is known about the fine-scale space use of the non-territorial females who do not engage in acoustic and visual displays. We tracked 17 females for 6 to 17 days using a harmonic direction finder to provide the first precise analysis of female space use in this species. Females moved on average 1 m per hour and the fastest movement, over 20 m per hour, was related to a subsequent mating event. Traveled distances and activity patterns on days of courtship and mating differed considerably from days without reproduction. Frogs moved more on days with lower temperature and more precipitation, but mating seemed to be the main trigger for female movement. We observed 21 courtships of 12 tagged females. For seven females, we observed two consecutive mating events. Estimated home ranges after 14 days varied considerably between individuals and courtship and mating associated space use made up for ∼30% of the home range. Allobates femoralis females spent large parts of their time in one to three small centers of use. Females did not adjust their time or space use to the density of males in their surroundings and did not show wide-ranging exploratory behavior. Our study demonstrates how tracking combined with detailed behavioral observations can reveal the patterns and drivers of fine-scale spatial behavior in sedentary species.

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Quantification and comparison of individual space-use strategies in foraging drift-feeding fish using fine-scale, multidimensional movement analysis

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/cjfas-2015-0006 ◽

2015 ◽

Vol 72 (11) ◽

pp. 1760-1768 ◽

Cited By ~ 6

Author(s):

Aurélien Vivancos ◽

Gerard P. Closs

Keyword(s):

Salmo Trutta ◽

Vertical Plane ◽

Movement Analysis ◽

Space Use ◽

Scale Space ◽

Visual Observation ◽

Two Dimensions ◽

Three Dimensions ◽

Fine Scale ◽

Drift Feeding

Fine-scale space-use of drift-feeding fish is underpinned by an energetic trade-off that makes spatial positioning paramount for fitness, especially in a group context. However, methodologies used to study the space-use of drift-feeding fish are mainly based on direct visual observation, and the accuracy of such an approach can be questionable. Furthermore, previous studies mainly focused on the space-use of territorial salmonids, as they are relatively easy to observe. Here, we use a digital imaging technique to manually extract the spatial position of fish and feeding events in three dimensions (3D), at a very fine spatiotemporal scale, from in situ stereo-video footages. We use a motion model to quantify individual space-use strategies in two dimensions (2D) through the horizontal plane (perpendicular to gravity) and through the vertical plane (parallel to the flow). We study territorial (brown trout, Salmo trutta) and nonterritorial (roundhead galaxiid, Galaxias anomalus) juvenile drift-feeding fish to test this methodology over a broad spectrum of drift-feeding fish space-use. Results show that the methodology used permits the reliable quantification of space-use by territorial and nonterritorial drift-feeding fish and could be used to reveal relevant insights on their respective behavioral ecologies.

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Fine-scale movement of juvenile Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus) during aggregations in the lower Saint John River Basin, New Brunswick, Canada

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/cjfas-2017-0430 ◽

2018 ◽

Vol 75 (12) ◽

pp. 2332-2342 ◽

Cited By ~ 3

Author(s):

Margaret M. Whitmore ◽

Matthew K. Litvak

Keyword(s):

River Basin ◽

Space Use ◽

Scale Space ◽

Low Flow ◽

Atlantic Sturgeon ◽

Fine Scale ◽

Vemco Positioning System ◽

Directional Movement ◽

Saint John ◽

Acipenser Oxyrinchus

Juvenile Atlantic sturgeon (Acipenser oxyrinchus oxyrinchus) form seasonal aggregations near the salt wedge in their natal river systems. We used an array of Vemco positioning system acoustic receivers to track fine-scale movement within aggregation sites in two rivers in the Saint John River Basin. We used the t-LoCoH convex hull construction algorithm to map space use and aggregation behavior and nonmetric multidimensional scaling to test for differences among rivers, seasons, and photoperiods. Aggregation sites consisted of small core areas, where juvenile Atlantic sturgeon remained for long periods, that are adjacent to foraging grounds. This structure was largely consistent between rivers and seasons. Directional movement within aggregation sites differed between rivers. In areas of high flow velocity, directional movement was parallel to flow and largely restricted to littoral areas, whereas areas of low flow exhibited no distinct patterns in directional movement. This indicates flow may be an important driver of fine-scale distribution within aggregation sites. Studies of fine-scale space use can inform future investigations of rearing capacity, aid in the identification of critical habitat, and inform management decisions.

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Variable habitat selection and movement patterns among Bullsnake (Pituophis catenifer sayi) populations in Saskatchewan

The Canadian Field-Naturalist ◽

10.22621/cfn.v132i2.2041 ◽

2019 ◽

Vol 132 (2) ◽

pp. 126-139 ◽

Cited By ~ 1

Author(s):

Tera L. Edkins ◽

Christopher M. Somers ◽

Mark C. Vanderwel ◽

Miranda J. Sadar ◽

Ray G. Poulin

Keyword(s):

Habitat Selection ◽

Radio Telemetry ◽

Geographic Location ◽

Space Use ◽

Fine Scale ◽

Range Limit ◽

Northern Range Limit ◽

Range Overlap ◽

Conservation Concern ◽

River Valleys

Pituophis catenifer sayi (Bullsnake) is a sparsely studied subspecies of conservation concern in Canada. Basic ecological information is lacking for P. c. sayi, which reaches its northern range limit in western Canada. To address this gap, we used radio-telemetry to examine space use and habitat selection in three populations of Bullsnakes in disjunct river valley systems (Frenchman, Big Muddy, and South Saskatchewan River Valleys) across their Saskatchewan range. Bullsnakes in two valleys used up to three times more space, travelled 2.5-times farther from overwintering sites, and had lower home range overlap than the third population. Landscape-level habitat selection was flexible, with snakes in all populations using both natural and human-modified habitats most frequently. Fine-scale habitat selection was also similar among populations, with Bullsnakes selecting sites within 1 m of refuges, regardless of whether they were natural or anthropogenic. Based on these results, Bullsnakes are flexible in their broad scale habitat use, as long as they are provided with fine scale refuge sites. The distribution of key seasonal resources appears to ultimately determine space use and habitat selection by Bullsnakes, regardless of the geographic location of the population.

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Spatial Causality in Bilateral Symmetry Detection

Perception ◽

10.1068/v970179 ◽

1997 ◽

Vol 26 (1_suppl) ◽

pp. 181-181

Author(s):

J Hulleman ◽

A H J Oomes

Keyword(s):

Spatial Scale ◽

Multiple Scales ◽

Reaction Times ◽

Bilateral Symmetry ◽

Scale Space ◽

Causality Principle ◽

Circular Aperture ◽

Fine Scale ◽

Black And White ◽

Random Patterns

We studied the influence of spatial scale on the detection of vertical and horizontal bilateral symmetry. The causality principle in scale - space theory states that increasing the spatial scale in a representation can only result in a decrease of structure. Consequently, a pattern can be random on the fine scale and symmetric on the coarse scale, never the reverse. Stimuli were bilaterally symmetric or random patterns, black-and-white on a grey background, with a circular aperture. The minimal scale was systematically varied and stimuli ranged from conventional noise patterns, through Dalmatian texture, to cow-like patterns. Observers had to judge whether a briefly presented pattern was ‘symmetric’ or ‘random’. Symmetric patterns resulted in a high accuracy (95%) with no influence of scale, and reaction times with a small linear decrease for increasing scale. Random patterns yielded an accuracy increasing from 70% at the smallest scale to 95% at the middle scales. Reaction times showed a similar pattern: largest at the smallest scales and decreasing to values equal to the symmetric condition at the middle scales. Results were similar for vertical and horizontal bilateral symmetry, though the effect for small scales in the random condition was more pronounced in the horizontal case. We conclude that bilateral symmetry is processed at multiple scales with coarse structures available slightly earlier than fine ones. The dramatic decrease of performance for fine-scale patterns is due to the causality effect; random patterns are judged as symmetric when the smallest scale information is not (yet) available.

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Space use by resident and transient coyotes in an urban–rural landscape mosaic

Wildlife Research ◽

10.1071/wr15020 ◽

2015 ◽

Vol 42 (6) ◽

pp. 461 ◽

Cited By ~ 14

Author(s):

Numi Mitchell ◽

Michael W. Strohbach ◽

Ralph Pratt ◽

Wendy C. Finn ◽

Eric G. Strauss

Keyword(s):

Land Cover ◽

Rhode Island ◽

Human Activity ◽

Urban Areas ◽

Agricultural Land ◽

Space Use ◽

Scale Space ◽

Rural Landscape ◽

Urban Land Use ◽

Mixed Effect

Context Coyotes (Canis latrans) have adapted successfully to human landscape alteration in the past 150 years and in recent decades have successfully moved into urban areas. While this causes concern about human–wildlife conflicts, research also suggests that coyotes tend to avoid humans and human activity in urban areas. For improving management, a better understanding of space use by coyotes is needed. Aims To study how coyote social behaviour influences fine-scale space use in urban areas we present results from an extensive, multi-year GPS telemetry study (2005–13). The study area in coastal Rhode Island is a mosaic of rural, suburban and urban land use and coyotes have only recently arrived. Methods We differentiated between two social classes: residents (individuals that have established a territory; n = 24) and transients (individuals that have no territory; n = 7). Space use was analysed using mixed effect models and detailed land-cover data. Key results Coyotes tended to select for agricultural and densely vegetated land cover and against land used for housing and commerce. Pasture and cropland were preferred by residents and avoided by transients, especially at night, indicating the role of agricultural land as prime foraging habitat. Both groups selected densely vegetated land cover for daytime shelter sites. Transients selected for densely vegetated land cover both day and night, indicating use for both shelter and foraging. Resident coyotes avoided high- and medium-density housing more than transients. Conclusions We interpret land-cover selection by resident coyotes as indicative of coyote habitat preference, while transients more often occupied marginal habitats that probably do not reflect their preferences. Differences in land cover selection between residents and transients suggest that transients have a corollary strategy to avoid residents. Implications With cover and food appearing to be important drivers of space use, coexistence strategies can build on controlling food resources as well as on the tendency of coyotes to avoid humans. Nevertheless, transients, having the need to avoid territorial resident coyotes as well, show a reduced aversion to land cover with high human activity, creating a higher potential for human–wildlife conflicts.

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Circles within spirals, wheels within wheels; Body rotation facilitates critical insights into animal behavioural ecology

10.23889/suthesis.58403 ◽

2021 ◽

Author(s):

◽

Richard M. Gunner

Keyword(s):

Resource Selection ◽

Animal Movement ◽

Movement Ecology ◽

Dead Reckoning ◽

Space Use ◽

Behavioural Ecology ◽

Motion Sensors ◽

Fine Scale ◽

Body Rotation ◽

Model Species

How animals behave is fundamental to enhancing their lifetime fitness, so defining how animals move in space and time relates to many ecological questions, including resource selection, activity budgets and animal movement networks. Historically, animal behaviour and movement has been defined by direct observation, however recent advancements in biotelemetry have revolutionised how we now assess behaviour, particularly allowing animals to be monitored when they cannot be seen. Studies now pair ‘convectional’ radio telemetries with motion sensors to facilitate more detailed investigations of animal space-use. Motion sensitive tags (containing e.g., accelerometers and magnetometers) provide precise data on body movements which characterise behaviour, and this has been exemplified in extensive studies using accelerometery data, which has been linked to space-use defined by GPS. Conversely, consideration of body rotation (particularly change in yaw) is virtually absent within the biologging literature, even though various scales of yaw rotation can reveal important patterns in behaviour and movement, with animal heading being a fundamental component characterising space-use. This thesis explores animal body angles, particularly about the yaw axis, for elucidating animal movement ecology. I used five model species (a reptile, a mammal and three birds) to demonstrate the value of assessing body rotation for investigating fine-scale movement-specific behaviours. As part of this, I advanced the ‘dead-reckoning’ method, where fine-scale animal movement between temporally poorly resolved GPS fixes can be deduced using heading vectors and speed. I addressed many issues with this protocol, highlighting errors and potential solutions but was able to show how this approach leads to insights into many difficult-to-study animal behaviours. These ranged from elucidating how and where lions cross supposedly impermeable man-made barriers to examining how penguins react to tidal currents and then navigate their way to their nests far from the sea in colonies enclosed within thick vegetation.

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