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- Moveapps WorkflowMoveApps Workflow: Nest Flight Statistics(2023-02-03) Kölzsch, Andrea; Gal, Johannesdetermines flight speed average and antimode, flight time per day, flight Altitude and nest use by radii - needs input from Nest Location and Nesting Duration workflow
- Moveapps WorkflowMoveApps Workflow: Roost and Foraging Site Extraction(2022-11-14) Kölzsch, AndreaExtract roosts (stationary during night) or foraging sites (stationary during day) from movement tracks. Steps: selects locations on ground (low speed) and at night/day, extract sites where animals stay in defined radius for defined min. duration
- Moveapps WorkflowMoveApps Workflow: Morning Report(2022-07-21) Kölzsch, Andrea; Wikelski, MartinGet overview about your tags' performance and whereabouts.
- Moveapps WorkflowMoveApps Workflow: Nest Location and Nesting Duration(2023-02-02) Kölzsch, Andrea; Flack, Andreadetermines nests and breeding time intervals - use before Nest Flight Statistics workflow
- Moveapps WorkflowMoveapps Workflow: Migration Mapper(2022-07-22) Kölzsch, Andrea; Safi, KamranClean and filter your data to view migration tracks.
- Moveapps WorkflowMoveApps Workflow: Estimation of Utilisation Distribution by dyn Brownian Bridge Model(2023-01-13) Kölzsch, Andrea; Scharf, Anne KThis workflow shows how data of lesser white-fronted geese are downloaded, cleaned and filtered. Then, for spring as well as autumn migration, the dynamic Brownian Bridge model is used to calculated the Utilization Densities of the birds using the tracked area. Hotspots of use stand out as important sites for migration and stopover.
- Data packageData from: More grazing, more damage? Assessed yield loss on agricultural grassland relates non-linearly to goose grazing pressure(2023-11-29) Buitendijk, Nelleke H.; de Jager, Monique; Kruckenberg, Helmut; Kölzsch, Andrea; Moonen, Sander; Müskens, Gerhard J.D.M.; Nolet, Bart A.1. In recent decades, conflict between geese and agriculture has increased. Management practices to limit this conflict include concentrating geese in protected areas, derogation shooting or population reduction. To justify such management, we need to understand their effects on goose-related damages, which requires an understanding of how yield loss is influenced by goose abundance and species interactions. 2. We combined data from monthly goose counts and GPS-tracked geese to estimate grazing pressures by barnacle, white-fronted and greylag geese on agricultural grassland in Fryslân, the Netherlands. Using linear mixed models, we related this to damages assessed by professional inspectors. 3. Our results show a positive nonlinear relationship between yield loss and barnacle goose grazing pressure, where assessed damage increases with a decelerating rate as grazing pressure increases. For white-fronted geese, we find a negative relationship, while for greylag geese both positive and negative relationships occur. For each species, the relationship is influenced by the abundance of the other two. 4. For barnacle geese, the relationship can be explained by selection of fields offering the best balance between food intake and energy expenditure, and by grass regrowth, with highest grazing pressures occurring over a longer time period. The results for the other species are likely due to spatial and temporal differences in foraging preferences compared to barnacle geese, where larger species avoid areas with highest damages. 5. Synthesis and applications. Our results suggest that decreasing herbivore abundance may not translate directly to decreased yield loss, and management tools such as population reduction or derogation shooting should be used with care. Management aimed at concentrating geese in refuges could help to alleviate farmer–goose conflict, although further studies are required to determine if it would lead to damage reduction. We also find that not all species contribute equally to agricultural damage; care should be taken to ensure wildlife management targets the right species.
- Data packageData from: Towards a new understanding of migration timing: slower spring than autumn migration in geese reflects different decision rules for stopover use and departure(2016-02-25) Kölzsch, Andrea; Kruckenberg, Helmut; Glazov, Peter; Müskens, Gerhard J.D.M.; Wikelski, MartinAccording to migration theory and several empirical studies, long-distance migrants are more time-limited during spring migration and should therefore migrate faster in spring than in autumn. Competition for the best breeding sites is supposed to be the main driver, but timing of migration is often also influenced by environmental factors such as food availability and wind conditions. Using GPS tags, we tracked 65 greater white-fronted geese Anser albifrons migrating between western Europe and the Russian Arctic during spring and autumn migration over six different years. Contrary to theory, our birds took considerably longer for spring migration (83 days) than autumn migration (42 days). This difference in duration was mainly determined by time spent at stopovers. Timing and space use during migration suggest that the birds were using different strategies in the two seasons: In spring they spread out in a wide front to acquire extra energy stores in many successive stopover sites (to fuel capital breeding), which is in accordance with previous results that white-fronted geese follow the green wave of spring growth. In autumn they filled up their stores close to the breeding grounds and waited for supportive wind conditions to quickly move to their wintering grounds. Selection for supportive winds was stronger in autumn, when general wind conditions were less favourable than in spring, leading to similar flight speeds in the two seasons. In combination with less stopover time in autumn this led to faster autumn than spring migration. White-fronted geese thus differ from theory that spring migration is faster than autumn migration. We expect our findings of different decision rules between the two migratory seasons to apply more generally, in particular in large birds in which capital breeding is common, and in birds that meet other environmental conditions along their migration route in autumn than in spring.
- Data package2022_MoveApps_Koelzsch_Roost_and_Foraging_Site_Extraction(2022-11-14) Kölzsch, AndreaExtract roosts (stationary during night) or foraging sites (stationary during day) from movement tracks. Steps: selects locations on ground (low speed) and at night/day, extract sites where animals stay in defined radius for defined min. duration
- Data packageData from: Longer days enable higher diurnal activity for migratory birds [greater white-fronted geese](2021-03-24) Kölzsch, Andrea; Müskens, Gerhard J.D.M.; Moonen, Sander; Kruckenberg, Helmut; Glazov, Peter; Wikelski, Martin(1) Seasonal geophysical cycles strongly influence the activity of life on Earth because they affect environmental conditions like temperature, precipitation, and daylength. An increase in daylight availability during summer is especially enhanced when animals migrate along a latitudinal gradient. Yet, the question of how daylength (i.e. daylight availability) influences the activity patterns of long‐distance, latitudinal migrants is still unclear. (2) Here, we ask whether migration provides benefits to long‐distance migrants by enabling them to increase their diurnal movement activities due to an increase in daylight availability. To answer this question, we tested whether four vastly different species of long‐distance migratory birds--two arctic migrants and two mid‐latitude migrants--can capitalise on day length changes by adjusting their daily activity. (3) We quantified the relationship between daily activity (measured using accelerometer data) and day length, and estimated each species' daily activity patterns. In addition, we evaluated the role of day length as an ultimate driver of bird migration. (4) All four species exhibited longer activity periods during days with more daylight hours, showing a strong positive relationship between total daily activity and day length. The slope of this relationship varied between the different species, with activity increasing 1.5‐fold on average when migrating from wintering to breeding grounds. Underlying mechanisms of these relationships reveal two distinct patterns of daily activity. Flying foragers showed increasing activity patterns, i.e. their daytime activities rose uniformly up to solar noon and decreased until dusk, thereby exhibiting a season‐specific activity slope. In contrast, ground foragers showed a constant activity pattern, whereby they immediately increased their activity to a certain level and maintained this level throughout the day. (5) Our study reveals that long days allow birds to prolong their activity and increase their total daily activity. These findings highlight that daylight availability could be an additional ultimate cause of bird migration and act as a selective agent for the evolution of migration.