A stable home: Autocorrelated Kernel Density Estimated home ranges of the critically endangered Elongated Tortoise

Home range is a fundamental concept in ecology used to describe animal space use over their lifetimes. Numerous studies use a variety of metrics to quantify home range; however, most of these treat spatial data inappropriately. Here we re-analyse a publicly available data-set, collected by the authors of this study, using a relatively novel and appropriate home range metric Autocorrelated Kernel Density Estimators (AKDE). Our data includes the movements of 17 Elongated Tortoises (Indotestudo elongata; 12 females, 5 males) located on average once every three days for an average duration of 353.76 ±33.10 days. We found 14 of 17 individuals appear to be occupying a stable home range (using variograms to determine range residency). We made use of AKDEs bias-mitigating measures to counteract the low effective sample sizes stemming from low temporal resolution radio-tracking data. The average AKDE home range for all 14 individuals with range residency was 44.81 ±10.44 ha. Bayesian Regression Models suggest considerable overlap between male and female home range estimates despite males being physically larger than females in both mass and carapace length. These home range estimates have the added utility of being comparable with other studies, less susceptible to errors from a suboptimal tracking regime, and are optimised with code and data for inclusion in future meta-analyses.

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Home range and activity of African goshawks Accipiter tachiro in relation to their predation on bats

Koedoe ◽

10.4102/koedoe.v33i2.437 ◽

1990 ◽

Vol 33 (2) ◽

Cited By ~ 4

Author(s):

I.L. Rautenbach ◽

M.B. Fenton ◽

A.C. Kemp ◽

S.J. Van Jaarsveld

Keyword(s):

Home Range ◽

Adult Female ◽

Sex Ratios ◽

Home Ranges ◽

Radio Tracking ◽

High Fecundity ◽

Previous Summer

Winter radio-tracking of three African goshawks Accipiter tachiro showed that they each occupied well-wooded home ranges of at least 28 hectares. They perched and roosted mainly within densely foliaged trees and an adult female changed perches on average 4,7 times per hour. No crepuscular predation of bats was recorded, in contrast to regular summer predation on colonies of little free-tailed bats, Tadarida pumila, but winter emergence rates of these bats at dusk had dropped to < 5 of the previous summer. We predict that many accipiters will be regular predators of bats and that skewed sex ratios and high fecundity may be two means by which bats counter this predation.

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Allometry of home range size in lake and river fishes

Canadian Journal of Fisheries and Aquatic Sciences ◽

10.1139/f95-144 ◽

1995 ◽

Vol 52 (7) ◽

pp. 1499-1508 ◽

Cited By ~ 159

Author(s):

Charles K. Minns

Keyword(s):

Body Size ◽

Home Range ◽

Freshwater Fish ◽

Fish Population ◽

Home Range Size ◽

Range Size ◽

Territory Size ◽

Home Ranges ◽

Data Set ◽

Terrestrial Mammals

A data set assembled from published literature supported the hypotheses that (i) home range size increases allometrically with body size in temperate freshwater fishes, and (ii) fish home ranges are larger in lakes than rivers. The allometric model fitted was home range = A∙(body size)B. Home ranges in lakes were 19–23 times larger than those in rivers. Additional analyses showed that membership in different taxonomic groupings of fish, the presence–absence of piscivory, the method of measuring home range, and the latitude position of the water bodies were not significant predictive factors. Home ranges of freshwater fish were smaller than those of terrestrial mammals, birds, and lizards. Home ranges were larger than area per fish values derived by inverting fish population and assemblage density–size relationships from lakes and rivers and territory–size relationships in stream salmonids. The weight exponent (B) of fish home range was lower than values reported for other vertebrates, 0.58 versus a range of 0.96–1.14. Lake–river home range differences were consistent with differences reported in allometric models of freshwater fish density and production.

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Population-level inference for home-range areas

10.1101/2021.07.05.451204 ◽

2021 ◽

Author(s):

Christen Herbert Fleming ◽

Iman Deznabi ◽

Shauhin Alavi ◽

Margaret C. Crofoot ◽

Ben T. Hirsch ◽

...

Keyword(s):

Home Range ◽

Density Estimation ◽

Kernel Density Estimation ◽

Kernel Density ◽

Population Level ◽

Home Ranges ◽

Tracking Data ◽

Temporal Autocorrelation ◽

Time Space ◽

Minimal Convex

· Home-range estimates are a common product of animal tracking data, as each range informs on the area needed by a given individual. Population-level inference on home-range areas—where multiple individual home-ranges are considered to be sampled from a population—is also important to evaluate changes over time, space, or covariates, such as habitat quality or fragmentation, and for comparative analyses of species averages. Population-level home-range parameters have traditionally been estimated by first assuming that the input tracking data were sampled independently when calculating home ranges via conventional kernel density estimation (KDE) or minimal convex polygon (MCP) methods, and then assuming that those individual home ranges were measured exactly when calculating the population-level estimates. This conventional approach does not account for the temporal autocorrelation that is inherent in modern tracking data, nor for the uncertainties of each individual home-range estimate, which are often large and heterogeneous. · Here, we introduce a statistically and computationally efficient framework for the population-level analysis of home-range areas, based on autocorrelated kernel density estimation (AKDE), that can account for variable temporal autocorrelation and estimation uncertainty. · We apply our method to empirical examples on lowland tapir (Tapirus terrestris), kinkajou (Potos flavus), white‐nosed coati (Nasua narica), white-faced capuchin monkey (Cebus capucinus), and spider monkey (Ateles geoffroyi), and quantify differences between species, environments, and sexes. · Our approach allows researchers to more accurately compare different populations with different movement behaviors or sampling schedules, while retaining statistical precision and power when individual home-range uncertainties vary. Finally, we emphasize the estimation of effect sizes when comparing populations, rather than mere significance tests.

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ctmmweb: A graphical user interface for autocorrelation-informed home range estimation

10.1101/2020.05.11.087932 ◽

2020 ◽

Cited By ~ 2

Author(s):

Justin M. Calabrese ◽

Christen H. Fleming ◽

Michael J. Noonan ◽

Xianghui Dong

Keyword(s):

Home Range ◽

Kernel Density ◽

R Package ◽

Home Ranges ◽

Tracking Data ◽

Sampled Data ◽

Convex Polygons ◽

Range Estimation ◽

Empirical Reality ◽

Range Overlap

ABSTRACTEstimating animal home ranges is a primary purpose of collecting tracking data. All conventional home range estimators in widespread usage, including minimum convex polygons and kernel density estimators, assume independently sampled data. In stark contrast, modern GPS animal tracking datasets are almost always strongly autocorrelated. This incongruence between estimator assumptions and empirical reality leads to systematically underestimated home ranges. Autocorrelated kernel density estimation (AKDE) resolves this conflict by modeling the observed autocorrelation structure of tracking data during home range estimation, and has been shown to perform accurately across a broad range of tracking datasets. However, compared to conventional estimators, AKDE requires additional modeling steps and has heretofore only been accessible via the command-line ctmm R package. Here, we introduce ctmmweb, which provides a point-and-click graphical interface to ctmm, and streamlines AKDE, its prerequisite autocorrelation modeling steps, and a number of additional movement analyses. We demonstrate ctmmweb’s capabilities, including AKDE home range estimation and subsequent home range overlap analysis, on a dataset of four jaguars from the Brazilian Pantanal. We intend ctmmweb to open AKDE and related autocorrelation-explicit analyses to a wider audience of wildlife and conservation professionals.

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Birnbaum-Saunders Quantile Regression Models with Application to Spatial Data

Mathematics ◽

10.3390/math8061000 ◽

2020 ◽

Vol 8 (6) ◽

pp. 1000 ◽

Cited By ~ 5

Author(s):

Luis Sánchez ◽

Víctor Leiva ◽

Manuel Galea ◽

Helton Saulo

Keyword(s):

Quantile Regression ◽

Spatial Data ◽

Spatial Model ◽

Regression Models ◽

Maximum Likelihood Method ◽

Marginal Distribution ◽

Likelihood Method ◽

Model Parameters ◽

Data Set ◽

Quantile Regression Model

In the present paper, a novel spatial quantile regression model based on the Birnbaum–Saunders distribution is formulated. This distribution has been widely studied and applied in many fields. To formulate such a spatial model, a parameterization of the multivariate Birnbaum–Saunders distribution, where one of its parameters is associated with the quantile of the respective marginal distribution, is established. The model parameters are estimated by the maximum likelihood method. Finally, a data set is applied for illustrating the formulated model.

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Importance of canopy connectivity for home range and movements of the rainforest arboreal ringtail possum (Hemibelideus lemuroides)

Wildlife Research ◽

10.1071/wr06114 ◽

2007 ◽

Vol 34 (3) ◽

pp. 177 ◽

Cited By ~ 35

Author(s):

Robyn F. Wilson ◽

Helene Marsh ◽

John Winter

Keyword(s):

Home Range ◽

Negative Impact ◽

Ground Level ◽

Home Ranges ◽

Radio Tracking ◽

Minimum Convex Polygon ◽

The Road ◽

North East ◽

Wide Road ◽

Ringtail Possum

Roads and powerline corridors destroy canopy connectivity in the rainforest of north-east Australia. We tested the hypotheses that linear barriers affect (a) the alignment of home ranges, (b) use of habitat either side of linear barriers, and (c) the crossing of them by the strictly arboreal lemuroid ringtail possum (Hemibelideus lemuroides), which is known to be vulnerable to habitat fragmentation. Radio-tracking and a translocation experiment were conducted at a narrow 7-m-wide road and an 80-m-wide powerline. Homes ranges of lemuroid ringtails ranged from 0.15 to 1.67 ha (minimum convex polygon) and were aligned with the road but not powerline corridors. When lemuroid ringtails were experimentally translocated, wider canopy clearings over roads reduced their capacity to return to their original home range, and the powerline corridor was a nearly insurmountable barrier. No possums were observed crossing roads or the powerline corridor at ground level or residing in the intervening matrix, indicating that loss of canopy connectivity has a negative impact on their movements.

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The movement, roaming behaviour and home range of free-roaming domestic dogs, Canis lupus familiaris, in coastal New South Wales

Wildlife Research ◽

10.1071/wr97101 ◽

1999 ◽

Vol 26 (6) ◽

pp. 847 ◽

Cited By ~ 43

Author(s):

Paul D. Meek

Keyword(s):

Home Range ◽

Average Duration ◽

New South ◽

Home Range Size ◽

Domestic Dogs ◽

Home Ranges ◽

Canis Lupus Familiaris ◽

Aboriginal Community ◽

South Wales ◽

The Mean

In this study 10 free-roaming domestic dogs from an Aboriginal community were radio-collared to determine the sizes of their home ranges and to observe their wandering behaviour. Half of the radio-tagged dogs went on wandering forays, while the other five roamed only within the vicinity of the community. Home-range size was highly variable within the study group: the mean for the wandering dogs was 927 ha whereas that of the sedentary dogs was 2.6 ha. Dogs travelled 8–30 km on forays. All forays were initiated at night and those that were recorded had an average duration of 26 h. Foray destinations were usually riparian habitats where macropod quarry were abundant.

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Home ranges and movement schedules of sympatric bridled nailtail and black-striped wallabies

Wildlife Research ◽

10.1071/wr9960547 ◽

1996 ◽

Vol 23 (5) ◽

pp. 547 ◽

Cited By ~ 17

Author(s):

M Evans

Keyword(s):

Home Range ◽

Home Range Size ◽

Range Size ◽

Home Ranges ◽

Radio Tracking ◽

Wet Season ◽

Seasonal Differences ◽

Dry Seasons ◽

Species Movement ◽

Wet And Dry Seasons

Home ranges and movement schedules of sympatric bridled nailtail wallabies, Onychogalea fraenata, and black-striped wallabies, Macropus dorsalis, were studied during wet and dry seasons by radio-tracking. Home ranges of black-striped wallabies (91 ha) were much larger than those of bridled nailtail wallabies (40 ha). Home-range size differed between sexes for bridled nailtail wallabies (males, 59 ha; females, 26 ha), but not for black-striped wallabies. Intraspecific seasonal differences in home-range size were not significant. All home ranges included diurnal shelter habitat, although the preferred type of shelter habitat was different for each species. Movement schedules differed significantly between wet and dry seasons for black-striped wallabies (which made a higher frequency of longer-distance movements during the dry season than during the wet season), but not for bridled nailtail wallabies.

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Ain’t Nothing like Family—Female Brown Bears Share Their Home Range with Relatives

Diversity ◽

10.3390/d14010041 ◽

2022 ◽

Vol 14 (1) ◽

pp. 41

Author(s):

Astrid Olejarz ◽

Jouni Aspi ◽

Ilpo Kojola ◽

Vesa Nivala ◽

Alina K. Niskanen ◽

...

Keyword(s):

Home Range ◽

Spatial Data ◽

Ursus Arctos ◽

Home Ranges ◽

Brown Bears ◽

Home Range Overlap ◽

Animal Populations ◽

Centroid Distance ◽

Range Overlap ◽

Eastern Finland

Sociality in animal populations is a continuum, and interactions between conspecifics are meaningful for all vertebrates. Ignorance of social structures can lead to misunderstanding their ecology and, consequently, to unsuccessful species management. Here, we combined genetic and spatial data on radio-collared brown bears (Ursus arctos) to investigate kin-related home range overlap and kin-related centroid distance within central and eastern Finland. We found that the extent of home range overlap was positively correlated with relatedness among adult females. In addition, home range centroid distance decreased as relatedness increased. Moreover, there were significant differences between the two studied regions: female brown bears in central Finland were more closely related to each other, and the sizes of their home ranges were larger than those in eastern Finland. The smaller home ranges and lower degree of relatedness among bears in eastern Finland might be a result of the substantially higher hunting pressure in the area, combined with immigration of new unrelated individuals from Russia.

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Home range, nest use and activity of the Tasmanian bettong, Bettongia gaimardi

Wildlife Research ◽

10.1071/wr9930087 ◽

1993 ◽

Vol 20 (1) ◽

pp. 87 ◽

Cited By ~ 19

Author(s):

RJ Taylor

Keyword(s):

Home Range ◽

Plant Material ◽

Home Range Size ◽

Range Size ◽

Ground Vegetation ◽

Home Ranges ◽

Regular Pattern ◽

Radio Tracking ◽

Tracking Period

Home range, nest use and activity of the Tasmanian bettong, Bettongia gaimardi, was investigated in northern Tasmania. During 3-week periods in August and November 1986 and February and May 1987 radio-tracking of six females and three males was undertaken, five of these being tracked in more than one period. Home ranges of males were larger than those of females. There was no indication of any major differences in home-range size or shifts in location of home ranges between seasons. Nightly patterns of movement were essentially random with distances of 500-600 m between half-hourly locations being not uncommon. Males occasionally showed a more regular pattern of movement possibly related to searching for oestrous females. Bettongs became active soon after dark. The number of hours spent active was greatest during May (79% of length of night) and lowest during November (93% of night). Bettongs occasionally rested at night between two bouts of activity. Nests are formed from a hollowed-out bundle of plant material and located under fallen trees, shrubs or logs, or under low shrubs or clumps of ground vegetation such as Lomandra. Individuals used 3-6 nests per 3-week tracking period. Nests were usually only used consecutively for one or two nights, and different nests were used to different extents. A different set of nests tended to be used in different months. Nests showed some tendency to be located at one end of the home range. Nesting areas used by different individuals overlapped.

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