Generalizing the first-difference correlated random walk for marine animal movement data

Data prediction and imputation are important parts of marine animal movement trajectory analysis as they can help researchers understand animal movement patterns and address missing data issues. Compared with traditional methods, deep learning methods can usually provide enhanced pattern extraction capabilities, but their applications in marine data analysis are still limited. In this research, we propose a composite deep learning model to improve the accuracy of marine animal trajectory prediction and imputation. The model extracts patterns from the trajectories with an encoder network and reconstructs the trajectories using these patterns with a decoder network. We use attention mechanisms to highlight certain extracted patterns as well for the decoder. We also feed these patterns into a second decoder for prediction and imputation. Therefore, our approach is a coupling of unsupervised learning with the encoder and the first decoder and supervised learning with the encoder and the second decoder. Experimental results demonstrate that our approach can reduce errors by at least 10% on average comparing with other methods.

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Evidence for intermittency and a truncated power law from highly resolved aphid movement data

Journal of The Royal Society Interface ◽

10.1098/rsif.2009.0121 ◽

2009 ◽

Vol 7 (42) ◽

pp. 199-208 ◽

Cited By ~ 42

Author(s):

Alla Mashanova ◽

Tom H. Oliver ◽

Vincent A. A. Jansen

Keyword(s):

Random Walk ◽

Power Law ◽

Animal Movement ◽

Power Laws ◽

Frequent Change ◽

Directed Movement ◽

Movement Data ◽

Data Points ◽

Aphid Movement ◽

Two Phases

Power laws are increasingly used to describe animal movement. Despite this, the use of power laws has been criticized on both empirical and theoretical grounds, and alternative models based on extensions of conventional random walk theory (Brownian motion) have been suggested. In this paper, we analyse a large volume of data of aphid walking behaviour (65 068 data points), which provides a highly resolved dataset to investigate the pattern of movement. We show that aphid movement is intermittent—with alternations of a slow movement with frequent change of direction and a fast, relatively directed movement—and that the fast movement consists of two phases—a strongly directed phase that gradually changes into an uncorrelated random walk. By measuring the mean-squared displacement and the duration of non-stop movement episodes we found that both spatial and temporal aspects of aphid movement are best described using a truncated power law approach. We suggest that the observed spatial pattern arises from the duration of non-stop movement phases rather than from correlations in turning angles. We discuss the implications of these findings for interpreting movement data, such as distinguishing between movement and non-movement, and the effect of the range of data used in the analysis on the conclusions.

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Movement syndromes of a Neotropical frugivorous bat inhabiting heterogeneous landscapes in Brazil

Movement Ecology ◽

10.1186/s40462-021-00266-6 ◽

2021 ◽

Vol 9 (1) ◽

Author(s):

Patricia Kerches-Rogeri ◽

Danielle Leal Ramos ◽

Jukka Siren ◽

Beatriz de Oliveira Teles ◽

Rafael Souza Cruz Alves ◽

...

Keyword(s):

Site Fidelity ◽

Animal Movement ◽

Radio Telemetry ◽

Food Resource ◽

Movement Behavior ◽

Movement Activity ◽

Landscape Features ◽

Heterogeneous Landscapes ◽

Movement Data ◽

High Site

Abstract Background There is growing evidence that individuals within populations can vary in both habitat use and movement behavior, but it is still not clear how these two relate to each other. The aim of this study was to test if and how individual bats in a Stunira lilium population differ in their movement activity and preferences for landscape features in a correlated manner. Methods We collected data on movements of 27 individuals using radio telemetry. We fitted a heterogeneous-space diffusion model to the movement data in order to evaluate signals of movement variation among individuals. Results S. lilium individuals generally preferred open habitat with Solanum fruits, regularly switched between forest and open areas, and showed high site fidelity. Movement variation among individuals could be summarized in four movement syndromes: (1) average individuals, (2) forest specialists, (3) explorers which prefer Piper, and (4) open area specialists which prefer Solanum and Cecropia. Conclusions Individual preferences for landscape features plus food resource and movement activity were correlated, resulting in different movement syndromes. Individual variation in preferences for landscape elements and food resources highlight the importance of incorporating explicitly the interaction between landscape structure and individual heterogeneity in descriptions of animal movement.

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Joint estimation over multiple individuals improves behavioural state inference from animal movement data

Scientific Reports ◽

10.1038/srep20625 ◽

2016 ◽

Vol 6 (1) ◽

Cited By ~ 69

Author(s):

Ian Jonsen

Keyword(s):

Animal Movement ◽

Joint Estimation ◽

Behavioural State ◽

Movement Data ◽

State Inference

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A compass without a map: tortuosity and orientation of eastern painted turtles (Chrysemys picta picta) released in unfamiliar territory

Canadian Journal of Zoology ◽

10.1139/z06-102 ◽

2006 ◽

Vol 84 (8) ◽

pp. 1129-1137 ◽

Cited By ~ 37

Author(s):

I.R. Caldwell ◽

V.O. Nams

Keyword(s):

Fractal Dimension ◽

Random Walk ◽

Spatial Scales ◽

Chrysemys Picta ◽

Reference Stimulus ◽

Correlated Random Walk ◽

Specific Mechanism ◽

Minimal Time ◽

Painted Turtles

Orientation mechanisms allow animals to spend minimal time in hostile areas while reaching needed resources. Identification of the specific mechanism used by an animal can be difficult, but examining an animal's path in familiar and unfamiliar areas can provide clues to the type of mechanism in use. Semiaquatic turtles are known to use a homing mechanism in familiar territory to locate their home lake while on land, but little is known about their ability to locate habitat in unfamiliar territory. We tested the tortuosity and orientation of 60 eastern painted turtles ( Chrysemys picta picta (Schneider, 1783)). We released turtles at 20 release points located at five distances and in two directions from two unfamiliar lakes. Turtle trails were quite straight (fractal dimension between 1.1 and 1.025) but were not oriented towards water from any distance (V-test; u < 0.72; P > 0.1). Turtles maintained their initially chosen direction but either could not detect water or were not motivated to reach it. Furthermore, paths were straighter at larger spatial scales than at smaller spatial scales, which could not have occurred if the turtles had been using a correlated random walk. Turtles must therefore be using a reference stimulus for navigation even in unfamiliar areas.

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Running on empty: recharge dynamics from animal movement data

Ecology Letters ◽

10.1111/ele.13198 ◽

2018 ◽

Cited By ~ 2

Author(s):

Mevin B. Hooten ◽

Henry R. Scharf ◽

Juan M. Morales

Keyword(s):

Animal Movement ◽

Movement Data

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Cattle trade between and within biomes in the state of Mato Grosso, Brazil

Pesquisa Veterinária Brasileira ◽

10.1590/1678-5150-pvb-5661 ◽

2018 ◽

Vol 38 (11) ◽

pp. 2023-2028

Author(s):

Rísia L. Negreiros ◽

José H.H. Grisi-Filho ◽

Ricardo A. Dias ◽

Fernando Ferreira ◽

Valéria S.F. Homem ◽

...

Keyword(s):

Infectious Diseases ◽

Animal Movement ◽

Control Strategies ◽

The State ◽

Disease Spread ◽

Mato Grosso ◽

Movement Data ◽

Cattle Movements ◽

Increased Risk ◽

And Control

ABSTRACT: The analysis of animal movement patterns may help identify farm premises with a potentially high risk of infectious disease introduction. Farm herd sizes and bovine movement data from 2007 in the state of Mato Grosso, Brazil, were analyzed. There are three different biomes in Mato Grosso: the Amazon, Cerrado, and Pantanal. The analysis of the animal trade between and within biomes would enable characterization of the connections between the biomes and the intensity of the internal trade within each biome. We conducted the following analyses: 1) the concentration of cattle on farm premises in the state and in each biome, 2) the number and relative frequency of cattle moved between biomes, and 3) the most frequent purposes for cattle movements. Twenty percent (20%) of the farm premises had 81.15% of the herd population. Those premises may be important not only for the spread of infectious diseases, but also for the implementation of surveillance and control strategies. Most of the cattle movement was intrastate (97.1%), and internal movements within each biome were predominant (88.6%). A high percentage of movement from the Pantanal was to the Cerrado (48.6%), the biome that received the most cattle for slaughter, fattening and reproduction (62.4%, 56.8%, and 49.1% of all movements for slaughter, fattening, and reproduction, respectively). The primary purposes for cattle trade were fattening (43.5%), slaughter (31.5%), and reproduction (22.7%). Presumably, movements for slaughter has a low risk of disease spread. In contrast, movements for fattening and reproduction purposes (66.2% of all movements) may contribute to an increased risk of the spread of infectious diseases.

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Distinguishing technology from biology: a critical review of the use of GPS telemetry data in ecology

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2010.0087 ◽

2010 ◽

Vol 365 (1550) ◽

pp. 2303-2312 ◽

Cited By ~ 316

Author(s):

Mark Hebblewhite ◽

Daniel T. Haydon

Keyword(s):

Animal Ecology ◽

Animal Movement ◽

Gps Telemetry ◽

Long Distance ◽

Location Data ◽

The Past ◽

Movement Data ◽

Migratory Songbirds ◽

Spatio Temporal ◽

Gps Devices

In the past decade, ecologists have witnessed vast improvements in our ability to collect animal movement data through animal-borne technology, such as through GPS or ARGOS systems. However, more data does not necessarily yield greater knowledge in understanding animal ecology and conservation. In this paper, we provide a review of the major benefits, problems and potential misuses of GPS/Argos technology to animal ecology and conservation. Benefits are obvious, and include the ability to collect fine-scale spatio-temporal location data on many previously impossible to study animals, such as ocean-going fish, migratory songbirds and long-distance migratory mammals. These benefits come with significant problems, however, imposed by frequent collar failures and high cost, which often results in weaker study design, reduced sample sizes and poorer statistical inference. In addition, we see the divorcing of biologists from a field-based understanding of animal ecology to be a growing problem. Despite these difficulties, GPS devices have provided significant benefits, particularly in the conservation and ecology of wide-ranging species. We conclude by offering suggestions for ecologists on which kinds of ecological questions would currently benefit the most from GPS/Argos technology, and where the technology has been potentially misused. Significant conceptual challenges remain, however, including the links between movement and behaviour, and movement and population dynamics.

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