Movement EcologyPub Date : 2024-06-08DOI: 10.1186/s40462-024-00483-9
Yumei Luo, Jiming Xie, Lin Zhu, Can Dai
{"title":"Successive stamen movement in Saxifraga candelabrum is responsive to weather and pollinator visits.","authors":"Yumei Luo, Jiming Xie, Lin Zhu, Can Dai","doi":"10.1186/s40462-024-00483-9","DOIUrl":"10.1186/s40462-024-00483-9","url":null,"abstract":"<p><strong>Background: </strong>Successive stamen movement is a complex plant behavior involving successive uplift of stamens and pollen release, which plays a role in reducing sexual interference, increasing pollen deposition and promoting pollen export. Although reported from several taxa, studies on whether the movement can be influenced by abiotic and biotic factors are scarce.</p><p><strong>Methods: </strong>In this study, we here for the first time described a pattern of successive stamen movement in Saxifraga candelabrum (Saxifragaceae). We then compared the rates of stamen movement in S. candelabrum under different weather and varying pollinator visits. Pollen packaging and presentation schedule of S. candelabrum were also investigated.</p><p><strong>Results: </strong>The results showed that the number of stamens bent per day in sunny days was significantly higher than overcast and rain. Flowers that receive more pollinator visits (control treatment) had significantly higher number of stamen movement than those that received fewer (removal treatment) and none (bagging treatment). Throughout the staminate phase of a flower, there was a progressive increase in both pollen quantity of individual stamens and pollen presentation during each day.</p><p><strong>Conclusion: </strong>Our research demonstrates that successive stamen movement in S. candelabrum was accelerated by favorable weather and increased pollinator visits, which may promote pollen export. Moreover, incremental pollen packaging is likely an adaptation to seasonal regularity in variations of sex ratio resulting from protandry.</p>","PeriodicalId":54288,"journal":{"name":"Movement Ecology","volume":"12 1","pages":"43"},"PeriodicalIF":4.1,"publicationDate":"2024-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11162003/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141293956","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Movement EcologyPub Date : 2024-06-07DOI: 10.1186/s40462-024-00481-x
Luciana C Ferreira, Curt Jenner, Micheline Jenner, Vinay Udyawer, Ben Radford, Andrew Davenport, Luciana Moller, Virginia Andrews-Goff, Mike Double, Michele Thums
{"title":"Predicting suitable habitats for foraging and migration in Eastern Indian Ocean pygmy blue whales from satellite tracking data.","authors":"Luciana C Ferreira, Curt Jenner, Micheline Jenner, Vinay Udyawer, Ben Radford, Andrew Davenport, Luciana Moller, Virginia Andrews-Goff, Mike Double, Michele Thums","doi":"10.1186/s40462-024-00481-x","DOIUrl":"10.1186/s40462-024-00481-x","url":null,"abstract":"<p><strong>Background: </strong>Accurate predictions of animal occurrence in time and space are crucial for informing and implementing science-based management strategies for threatened species.</p><p><strong>Methods: </strong>We compiled known, available satellite tracking data for pygmy blue whales in the Eastern Indian Ocean (n = 38), applied movement models to define low (foraging and reproduction) and high (migratory) move persistence underlying location estimates and matched these with environmental data. We then used machine learning models to identify the relationship between whale occurrence and environment, and predict foraging and migration habitat suitability in Australia and Southeast Asia.</p><p><strong>Results: </strong>Our model predictions were validated by producing spatially varying accuracy metrics. We identified the shelf off the Bonney Coast, Great Australian Bight, and southern Western Australia as well as the slope off the Western Australian coast as suitable habitat for migration, with predicted foraging/reproduction suitable habitat in Southeast Asia region occurring on slope and in deep ocean waters. Suitable foraging habitat occurred primarily on slope and shelf break throughout most of Australia, with use of the continental shelf also occurring, predominanly in South West and Southern Australia. Depth of the water column (bathymetry) was consistently a top predictor of suitable habitat for most regions, however, dynamic environmental variables (sea surface temperature, surface height anomaly) influenced the probability of whale occurrence.</p><p><strong>Conclusions: </strong>Our results indicate suitable habitat is related to dynamic, localised oceanic processes that may occur at fine temporal scales or seasonally. An increase in the sample size of tagged whales is required to move towards developing more dynamic distribution models at seasonal and monthly temporal scales. Our validation metrics also indicated areas where further data collection is needed to improve model accuracy. This is of particular importance for pygmy blue whale management, since threats (e.g., shipping, underwater noise and artificial structures) from the offshore energy and shipping industries will persist or may increase with the onset of an offshore renewable energy sector in Australia.</p>","PeriodicalId":54288,"journal":{"name":"Movement Ecology","volume":"12 1","pages":"42"},"PeriodicalIF":4.1,"publicationDate":"2024-06-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11157879/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141285404","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Movement EcologyPub Date : 2024-05-30DOI: 10.1186/s40462-024-00479-5
Susanne Jenni-Eiermann, Felix Liechti, Martins Briedis, Yann Rime, Lukas Jenni
{"title":"Energy supply during nocturnal endurance flight of migrant birds: effect of energy stores and flight behaviour.","authors":"Susanne Jenni-Eiermann, Felix Liechti, Martins Briedis, Yann Rime, Lukas Jenni","doi":"10.1186/s40462-024-00479-5","DOIUrl":"10.1186/s40462-024-00479-5","url":null,"abstract":"<p><strong>Background: </strong>Migrating birds fly non-stop for hours or even for days. They rely mainly on fat as fuel complemented by a certain amount of protein. Studies on homing pigeons and birds flying in a wind-tunnel suggest that the shares of fat and protein on total energy expenditure vary with flight duration and body fat stores. Also, flight behaviour, such as descending flight, is expected to affect metabolism. However, studies on free flying migrant birds under natural conditions are lacking.</p><p><strong>Methods: </strong>On a Swiss Alpine pass, we caught three species of nocturnal migrant passerines out of their natural migratory flight. Since most night migrants start soon after dusk, we used time since dusk as a measure of flight duration. We used plasma concentrations of metabolites of the fat, protein, and carbohydrate metabolism as indicators of relative fuel use. We used flight altitudes of birds tracked with radar and with atmospheric pressure loggers to characterize flight behaviour.</p><p><strong>Results: </strong>The indicators of fat catabolism (triglycerides, very low-density lipoproteins, glycerol) were positively correlated with body energy stores, supporting earlier findings that birds with high fat stores have a higher fat catabolism. As expected, plasma levels of triglycerides, very low-density lipoproteins, glycerol and ß-hydroxy-butyrate increased at the beginning of the night, indicating that nocturnal migrants increased their fat metabolism directly after take-off. Surprisingly, fat catabolism as well as glucose levels decreased in the second half of the night. Data from radar observations showed that the number of birds aloft, their mean height above ground and vertical flight speed decreased after midnight. Together with the findings from atmospheric pressure-loggers put on three species, this shows that nocturnal migrants migrating over continental Europe descend slowly during about 1.5 h before final landfall at night, which results in 11-30% energy savings according to current flight models.</p><p><strong>Conclusions: </strong>We suggest that this slow descent reduces energy demands to an extent which is noticeable in the plasma concentration of lipid, protein, and carbohydrate metabolites. The slow descent may facilitate the search for a suitable resting habitat and serve to refill glycogen stores needed for foraging and predator escape when landed.</p>","PeriodicalId":54288,"journal":{"name":"Movement Ecology","volume":"12 1","pages":"41"},"PeriodicalIF":4.1,"publicationDate":"2024-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11140942/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141181280","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Movement EcologyPub Date : 2024-05-30DOI: 10.1186/s40462-024-00480-y
Margaret M Lamont, Daniel Slone, James P Reid, Susan M Butler, Joseph Alday
{"title":"Deep vs shallow: GPS tags reveal a dichotomy in movement patterns of loggerhead turtles foraging in a coastal bay.","authors":"Margaret M Lamont, Daniel Slone, James P Reid, Susan M Butler, Joseph Alday","doi":"10.1186/s40462-024-00480-y","DOIUrl":"10.1186/s40462-024-00480-y","url":null,"abstract":"<p><strong>Background: </strong>Individual variation in movement strategies of foraging loggerhead turtles have been documented on the scale of tens to hundreds of kilometers within single ocean basins. Use of different strategies among individuals may reflect variations in resources, predation pressure or competition. It is less common for individual turtles to use different foraging strategies on the scale of kilometers within a single coastal bay. We used GPS tags capable of back-filling fine-scale locations to document movement patterns of loggerhead turtles in a coastal bay in Northwest Florida, U.S.A.</p><p><strong>Methods: </strong>Iridium-linked GPS tags were deployed on loggerhead turtles at a neritic foraging site in Northwest Florida. After filtering telemetry data, point locations were transformed to movement lines and then merged with the original point file to define travel paths and assess travel speed. Home ranges were determined using kernel density function. Diurnal behavioral shifts were examined by examining turtle movements compared to solar time.</p><p><strong>Results: </strong>Of the 11 turtles tagged, three tracked turtles remained in deep (~ 6 m) water for almost the entire tracking period, while all other turtles undertook movements from deep water locations, located along edges and channels, to shallow (~ 1-2 m) shoals at regular intervals and primarily at night. Three individuals made short-term movements into the Gulf of Mexico when water temperatures dropped, and movement speeds in the Gulf were greater than those in the bay. Turtles exhibited a novel behavior we termed drifting.</p><p><strong>Conclusions: </strong>This study highlighted the value provided to fine-scale movement studies for species such as sea turtles that surface infrequently by the ability of these GPS tags to store and re-upload data. Future use of these tags at other loggerhead foraging sites, and concurrent with diving and foraging data, would provide a powerful tool to better understand fine-scale movement patterns of sea turtles.</p>","PeriodicalId":54288,"journal":{"name":"Movement Ecology","volume":"12 1","pages":"40"},"PeriodicalIF":4.1,"publicationDate":"2024-05-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11140867/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141181273","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Movement EcologyPub Date : 2024-05-21DOI: 10.1186/s40462-024-00478-6
Nathalie Jreidini, David M Green
{"title":"Study methodology impacts density-dependent dispersal observations: a systematic review.","authors":"Nathalie Jreidini, David M Green","doi":"10.1186/s40462-024-00478-6","DOIUrl":"10.1186/s40462-024-00478-6","url":null,"abstract":"<p><p>The relationship between animal dispersal and conspecific density has been explored in various study systems but results in terms of both the magnitude and the direction of density dependence are inconsistent. We conducted a thorough review of the literature (2000-2023) and found k = 97 empirical studies of birds, fishes, herpetofauna (amphibians and reptiles), invertebrates, or mammals that had tested for a correlation between conspecific density and animal dispersal. We extracted categorical variables for taxonomic group, sex, age, migratory behavior, study design, dispersal metric, density metric and variable type, as well as temporal and spatial scale, to test each of their correlation with the effect of density on dispersal (Pearson's r) using linear regressions and multilevel mixed-effect modelling. We found certain biases in the published literature, highlighting that the impact of conspecific density on dispersal is not as widespread as it is thought to be. We also found no predominant trend for density-dependent dispersal across taxonomic groups. Instead, results show that the scale and metrics of empirical observations significantly affected analytical results, and heterogeneity measures were high within taxonomic groups. Therefore, the direction and magnitude of the interaction between density and dispersal in empirical studies could partially be attributed to the data collection method involved. We suggest that the contradictory observations for density-dependent dispersal could be explained by dispersal-dependent density, where density is driven by movement instead, and urge researchers to either test this interaction when applicable or consider this perspective when reporting results.</p>","PeriodicalId":54288,"journal":{"name":"Movement Ecology","volume":"12 1","pages":"39"},"PeriodicalIF":4.1,"publicationDate":"2024-05-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11107046/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141077325","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Movement EcologyPub Date : 2024-05-09DOI: 10.1186/s40462-024-00474-w
Raquel García-Vernet, Diego Rita, Martine Bérubé, Julia Elgueta-Serra, Marina Pascual Guasch, Gísli Víkingsson, Marc Ruiz-Sagalés, Asunción Borrell, Alex Aguilar
{"title":"Order within chaos: potential migratory strategies and individual associations in fin whales feeding off Iceland.","authors":"Raquel García-Vernet, Diego Rita, Martine Bérubé, Julia Elgueta-Serra, Marina Pascual Guasch, Gísli Víkingsson, Marc Ruiz-Sagalés, Asunción Borrell, Alex Aguilar","doi":"10.1186/s40462-024-00474-w","DOIUrl":"10.1186/s40462-024-00474-w","url":null,"abstract":"<p><strong>Background: </strong>The life cycle of most baleen whales involves annual migrations from low-latitude breeding grounds to high latitude feeding grounds. In most species, these migrations are traditionally considered to be carried out according to information acquired through vertical social learning during the first months of life and made individually. However, some recent studies have suggested a more complex scenario, particularly for the species of the Balaenoptera genus.</p><p><strong>Methods: </strong>Here, we studied the variation of δ<sup>15</sup>N and δ<sup>13</sup>C values along the growth axis of the baleen plate from 24 fin whales feeding off western Iceland to delve into their pattern of movements and to identify potential associations between individuals. The segment of baleen plate analyzed informed about at least two complete migratory cycles. We performed cluster analyses through two different methodologies and, whenever possible, we genotyped 20 microsatellite loci to determine potential existence of kinship.</p><p><strong>Results: </strong>Results of the of δ<sup>15</sup>N and δ<sup>13</sup>C values agree with a dispersion strategy in the winter breeding grounds. However, and despite the overall large variability, several pairs or groups of individuals with no kinship showed highly similar isotopic patterns for two consecutive years for both δ<sup>15</sup>N and δ<sup>13</sup>C values.</p><p><strong>Conclusions: </strong>Our results suggest that, notably, some whales without kinship share the same migratory regime and destinations. We hypothesize that this could reflect either: (i) the sharing of particularly beneficial migratory regimes, and/or (ii) long-term association between individuals.</p>","PeriodicalId":54288,"journal":{"name":"Movement Ecology","volume":"12 1","pages":"36"},"PeriodicalIF":4.1,"publicationDate":"2024-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11080271/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140900257","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Movement EcologyPub Date : 2024-05-09DOI: 10.1186/s40462-024-00469-7
Miguel Gandra, Alexander C Winkler, Pedro Afonso, David Abecasis
{"title":"Long-distance migrations and seasonal movements of meagre (Argyrosomus regius), a large coastal predator, along the Iberian Peninsula coast.","authors":"Miguel Gandra, Alexander C Winkler, Pedro Afonso, David Abecasis","doi":"10.1186/s40462-024-00469-7","DOIUrl":"10.1186/s40462-024-00469-7","url":null,"abstract":"<p><strong>Background: </strong>The meagre, Argyrosomus regius, is a large coastal predatory fish inhabiting waters from the north-eastern Atlantic and Mediterranean Sea, where it is targeted by commercial and recreational fisheries. Previous genetic studies have found an unexpectedly high population differentiation not only between the Atlantic and the Mediterranean, but also along the Atlantic coast. However, the reasons underpinning this genetic barrier remained unclear. Likewise, even though the species is amongst the world's largest marine teleosts, knowledge about its movement ecology and migratory behaviour remains notably scarce, and primarily reliant on fisheries-dependent data.</p><p><strong>Methods: </strong>In this study, we used a combination of acoustic telemetry and pop-up satellite archival tags to investigate the movements of 22 adult meagre (70-143 cm total length) along the Southwestern coast of the Iberian Peninsula.</p><p><strong>Results: </strong>Our results strongly suggest that the previously reported genetic differentiation is not maintained by limited adult dispersal/movement, as hypothesized. On the contrary, we documented some of the longest individual annual migrations ever recorded for a coastal teleost, up to > 2000 km, with frequent back-and-forth movements between the West and Southern Iberian coasts. Moreover, their detected regional movement patterns support the existence of a marked seasonal behavioural shift, with individuals being less active and moving to deeper waters during winter, and are consistent with spawning philopatry associated to their summer reproductive movements. Finally, we identified putative aggregation areas that may harbour important feeding/overwintering grounds.</p><p><strong>Conclusions: </strong>These findings shed new light on the movement and behaviour patterns of meagre that may be of particular importance for the conservation and spatial management of this species throughout its range, and open the door to further research on functional connectivity.</p>","PeriodicalId":54288,"journal":{"name":"Movement Ecology","volume":"12 1","pages":"35"},"PeriodicalIF":4.1,"publicationDate":"2024-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11080147/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140900255","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Movement EcologyPub Date : 2024-05-09DOI: 10.1186/s40462-024-00477-7
Marit Kelling, Shannon E Currie, Sara A Troxell, Christine Reusch, Manuel Roeleke, Uwe Hoffmeister, Tobias Teige, Christian C Voigt
{"title":"Effects of tag mass on the physiology and behaviour of common noctule bats.","authors":"Marit Kelling, Shannon E Currie, Sara A Troxell, Christine Reusch, Manuel Roeleke, Uwe Hoffmeister, Tobias Teige, Christian C Voigt","doi":"10.1186/s40462-024-00477-7","DOIUrl":"10.1186/s40462-024-00477-7","url":null,"abstract":"<p><strong>Background: </strong>External tags, such as transmitters and loggers, are often used to study bat movements. However, physiological and behavioural effects on bats carrying tags have rarely been investigated, and recommendations on the maximum acceptable tag mass are rather based on rules of thumb than on rigorous scientific assessment.</p><p><strong>Methods: </strong>We conducted a comprehensive three-step assessment of the potential physiological and behavioural effects of tagging bats, using common noctules Nyctalus noctula as a model. First, we examined seasonal changes in body mass. Second, we predicted and then measured potential changes in flight metabolic rate in a wind tunnel. Third, we conducted a meta-analysis of published data to assess effects of different tag masses on the weight and behaviour of bats.</p><p><strong>Results: </strong>Individual body mass of common noctules varied seasonally by 7.0 ± 2.6 g (range: 0.5-11.5 g). Aerodynamic theory predicted a 26% increase in flight metabolic rate for a common noctule equipped with a 3.8 g tag, equating to 14% of body mass. In a wind tunnel experiment, we could not confirm the predicted increase for tagged bats. Our meta-analysis revealed a weak correlation between tag mass and emergence time and flight duration in wild bats. Interestingly, relative tag mass (3-19% of bat body mass) was not related to body mass loss, but bats lost more body mass the longer tags were attached. Notably, relatively heavy bats lost more mass than conspecifics with a more average body mass index.</p><p><strong>Conclusion: </strong>Because heavy tags (> 3 g) were generally used for shorter periods of time than lighter tags (~ 1 g), the long-term effects of heavy tags on bats cannot be assessed at this time. Furthermore, the effects of disturbance and resource distribution in the landscape cannot be separated from those of tagging. We recommend that tags weighing 5-10% of a bat's mass should only be applied for a few days. For longer studies, tags weighing less than 5% of a bat's body mass should be used. To avoid adverse effects on bats, researchers should target individuals with average, rather than peak, body mass indices.</p>","PeriodicalId":54288,"journal":{"name":"Movement Ecology","volume":"12 1","pages":"38"},"PeriodicalIF":4.1,"publicationDate":"2024-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11084088/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140900254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Movement EcologyPub Date : 2024-05-09DOI: 10.1186/s40462-024-00476-8
David D Hofmann, Gabriele Cozzi, John Fieberg
{"title":"Methods for implementing integrated step-selection functions with incomplete data.","authors":"David D Hofmann, Gabriele Cozzi, John Fieberg","doi":"10.1186/s40462-024-00476-8","DOIUrl":"10.1186/s40462-024-00476-8","url":null,"abstract":"<p><p>Integrated step-selection analyses (iSSAs) are versatile and powerful frameworks for studying habitat and movement preferences of tracked animals. iSSAs utilize integrated step-selection functions (iSSFs) to model movements in discrete time, and thus, require animal location data that are regularly spaced in time. However, many real-world datasets are incomplete due to tracking devices failing to locate an individual at one or more scheduled times, leading to slight irregularities in the duration between consecutive animal locations. To address this issue, researchers typically only consider bursts of regular data (i.e., sequences of locations that are equally spaced in time), thereby reducing the number of observations used to model movement and habitat selection. We reassess this practice and explore four alternative approaches that account for temporal irregularity resulting from missing data. Using a simulation study, we compare these alternatives to a baseline approach where temporal irregularity is ignored and demonstrate the potential improvements in model performance that can be gained by leveraging these additional data. We also showcase these benefits using a case study on a spotted hyena (Crocuta crocuta).</p>","PeriodicalId":54288,"journal":{"name":"Movement Ecology","volume":"12 1","pages":"37"},"PeriodicalIF":4.1,"publicationDate":"2024-05-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11081933/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140900256","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Movement EcologyPub Date : 2024-04-30DOI: 10.1186/s40462-024-00473-x
Brendan D. Carson, Colin M. Orians, Elizabeth E. Crone
{"title":"Caterpillar movement mediates spatially local interactions and determines the relationship between population density and contact","authors":"Brendan D. Carson, Colin M. Orians, Elizabeth E. Crone","doi":"10.1186/s40462-024-00473-x","DOIUrl":"https://doi.org/10.1186/s40462-024-00473-x","url":null,"abstract":"While interactions in nature are inherently local, ecological models often assume homogeneity across space, allowing for generalization across systems and greater mathematical tractability. Density-dependent disease models are a prominent example of models that assume homogeneous interactions, leading to the prediction that disease transmission will scale linearly with population density. In this study, we examined how the scale of larval butterfly movement interacts with the resource landscape to influence the relationship between larval contact and population density in the Baltimore checkerspot (Euphydryas phaeton). Our study was inspired by the recent discovery of a viral pathogen that is transmitted horizontally among Baltimore checkerspot larvae. We used multi-year larvae location data across six Baltimore checkerspot populations in the eastern U.S. to test whether larval nests are spatially clustered. We then integrated these spatial data with larval movement data in different resource contexts to investigate whether heterogeneity in spatially local interactions alters the assumed linear relationship between larval nest density and contact. We used Correlated Random Walk (CRW) models and field observations of larval movement behavior to construct Probability Distribution Functions (PDFs) of larval dispersal, and calculated the overlap in these PDFs to estimate conspecific contact within each population. We found that all populations exhibited significant spatial clustering in their habitat use. Subsequent larval movement rates were influenced by encounters with host plants and larval age, and under many movement scenarios, the scale of predicted larval movement was not sufficient to allow for the “homogeneous mixing” assumed in density dependent disease models. Therefore, relationships between population density and larval contact were typically non-linear. We also found that observed use of available habitat patches led to significantly greater contact than would occur if habitat use were spatially random. These findings strongly suggest that incorporating larval movement and spatial variation in larval interactions is critical to modeling disease outcomes in E. phaeton. Epidemiological models that assume a linear relationship between population density and larval contact have the potential to underestimate transmission rates, especially in small populations that are already vulnerable to extinction.","PeriodicalId":54288,"journal":{"name":"Movement Ecology","volume":"52 1","pages":""},"PeriodicalIF":4.1,"publicationDate":"2024-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140829437","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}