Animal movement drives variation in seed dispersal distance in a plant–animal network

Frugivores play differing roles in shaping dispersal patterns yet seed dispersal distance is rarely quantified across entire communities. We model seed dispersal distance using gut passage times and bird movement for the majority (39 interactions) of known bird–tree interactions on the island of Saipan to highlight differences in seed dispersal distances provided by the five avian frugivores. One bird species was found to be a seed predator rather than a disperser. The remaining four avian species dispersed seeds but differences in seed dispersal distance were largely driven by interspecific variation in bird movement rather than intraspecific variation in gut passage times. The median dispersal distance was at least 56 m for all species-specific combinations, indicating all species play a role in reducing high seed mortality under the parent tree. However, one species—the Micronesian Starling—performed 94% of dispersal events greater than 500 m, suggesting this species could be a key driver of long-distance dispersal services (e.g. linking populations, colonizing new areas). Assessing variation in dispersal patterns across this network highlights key sources of variation in seed dispersal distances and suggests which empirical approaches are sufficient for modelling how seed dispersal mutualisms affect populations and communities.

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Long Distance Seed Dispersal by Forest Elephants

Frontiers in Ecology and Evolution ◽

10.3389/fevo.2021.789264 ◽

2021 ◽

Vol 9 ◽

Author(s):

John R. Poulsen ◽

Christopher Beirne ◽

Colin Rundel ◽

Melissa Baldino ◽

Seokmin Kim ◽

...

Keyword(s):

Seed Dispersal ◽

National Parks ◽

Community Dynamics ◽

Passage Time ◽

Dispersal Distance ◽

Long Distance ◽

Gut Passage ◽

Average Maximum ◽

Forest Elephants ◽

Dispersal Distances

By dispersing seeds long distances, large, fruit-eating animals influence plant population spread and community dynamics. After fruit consumption, animal gut passage time and movement determine seed dispersal patterns and distances. These, in turn, are influenced by extrinsic, environmental variables and intrinsic, individual-level variables. We simulated seed dispersal by forest elephants (Loxodonta cyclotis) by integrating gut passage data from wild elephants with movement data from 96 individuals. On average, elephants dispersed seeds 5.3 km, with 89% of seeds dispersed farther than 1 km. The longest simulated seed dispersal distance was 101 km, with an average maximum dispersal distance of 40.1 km. Seed dispersal distances varied among national parks, perhaps due to unmeasured environmental differences such as habitat heterogeneity and configuration, but not with human disturbance or habitat openness. On average, male elephants dispersed seeds farther than females. Elephant behavioral traits strongly influenced dispersal distances, with bold, exploratory elephants dispersing seeds 1.1 km farther than shy, idler elephants. Protection of forest elephants, particularly males and highly mobile, exploratory individuals, is critical to maintaining long distance seed dispersal services that shape plant communities and tropical forest habitat.

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High matrix vegetation decreases mean seed dispersal distance but increases long wind dispersal probability connecting local plant populations in agricultural landscapes

10.21203/rs.3.rs-278304/v1 ◽

2021 ◽

Author(s):

Sissi Donna Lozada Gobilard ◽

Florian Jeltsch ◽

Jinlei Zhu

Keyword(s):

Land Use ◽

Seed Dispersal ◽

Dispersal Distance ◽

Population Connectivity ◽

Agricultural Landscapes ◽

Long Distance Dispersal ◽

Long Distance ◽

Vegetation Height ◽

Positive Effect ◽

Seed Dispersal Distance

Abstract Background Seed dispersal plays an important role in population dynamics in agricultural ecosystems, but the effects of surrounding vegetation height on seed dispersal and population connectivity on the landscape scale have rarely been studied. Understanding the effects of surrounding vegetation height on seed dispersal will provide important information for land use management in agricultural landscapes to prevent the spread of undesired weeds or enhance functional connectivity. Methods We used two model species, Phragmites australis and Typha latifolia, growing in small natural ponds known as kettle holes, in an agricultural landscape to evaluate the effects of surrounding vegetation height on wind dispersal and population connectivity between kettle holes. Seed dispersal distance and the probability of long-distance dispersal (LDD) were simulated with the mechanistic WALD model under three scenarios of “low”, “dynamic” and “high” surrounding vegetation height. Connectivity between the origin and target kettle holes was quantified with a connectivity index adapted from Hanski and Thomas (1994). Results Our results show that mean seed dispersal distance decreases with the height of surrounding matrix vegetation, but the probability of long-distance dispersal (LDD) increases with vegetation height. This indicates an important vegetation-based trade-off between mean dispersal distance and LDD, which has an impact on connectivity. Conclusions Matrix vegetation height has a negative effect on mean seed dispersal distance but a positive effect on the probability of LDD. This positive effect and its impact on connectivity provide novel insights into landscape level (meta-)population and community dynamics — a change in matrix vegetation height by land use or climatic changes could strongly affect the spread and connectivity of wind-dispersed plants. The opposite effect of vegetation height on mean seed dispersal distance and the probability of LDD should therefore be considered in management and analyses of future land use and climate change effects.

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Dispersal distances and migration rates at the arctic treeline in Siberia – a genetic and simulation-based study

Biogeosciences ◽

10.5194/bg-16-1211-2019 ◽

2019 ◽

Vol 16 (6) ◽

pp. 1211-1224 ◽

Cited By ~ 8

Author(s):

Stefan Kruse ◽

Alexander Gerdes ◽

Nadja J. Kath ◽

Laura S. Epp ◽

Kathleen R. Stoof-Leichsenring ◽

...

Keyword(s):

Seed Dispersal ◽

Parentage Analysis ◽

Dispersal Distance ◽

Climate Feedback ◽

The Arctic ◽

Long Distance ◽

Central Siberia ◽

Migration Rates ◽

Dispersal Distances ◽

And Migration

Abstract. A strong temperature increase in the Arctic is expected to lead to latitudinal treeline shift. This tundra–taiga turnover would cause a positive vegetation–climate feedback due to albedo decrease. However, reliable estimates of tree migration rates are currently lacking due to the complex processes involved in forest establishment, which depend strongly on seed dispersal. We aim to fill this gap using LAVESI, an individual-based and spatially explicit Larix vegetation simulator. LAVESI was designed to simulate plots within homogeneous forests. Here, we improve the implementation of the seed dispersal function via field-based investigations. We inferred the effective seed dispersal distances of a typical open-forest stand on the southern Taymyr Peninsula (northern central Siberia) from genetic parentage analysis using eight nuclear microsatellite markers. The parentage analysis gives effective seed dispersal distances (median ∼10 m) close to the seed parents. A comparison between simulated and observed effective seed dispersal distances reveals an overestimation of recruits close to the releasing tree and a shorter dispersal distance generally. We thus adapted our model and used the newly parameterised version to simulate south-to-north transects; a slow-moving treeline front was revealed. The colonisation of the tundra areas was assisted by occasional long-distance seed dispersal events beyond the treeline area. The treeline (∼1 tree ha−1) advanced by ∼1.6 m yr−1, whereas the forest line (∼100 trees ha−1) advanced by only ∼0.6 m yr−1. We conclude that the treeline in northern central Siberia currently lags behind the current strong warming and will continue to lag in the near future.

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Estimating seed dispersal distance: A comparison of methods using animal movement and plant genetic data on two primate‐dispersed Neotropical plant species

Ecology and Evolution ◽

10.1002/ece3.5422 ◽

2019 ◽

Vol 9 (16) ◽

pp. 8965-8977 ◽

Cited By ~ 1

Author(s):

Tiziana A. Gelmi‐Candusso ◽

Ronald Bialozyt ◽

Darja Slana ◽

Ricardo Zárate Gómez ◽

Eckhard W. Heymann ◽

...

Keyword(s):

Seed Dispersal ◽

Plant Species ◽

Animal Movement ◽

Genetic Data ◽

Dispersal Distance ◽

Comparison Of Methods ◽

Seed Dispersal Distance

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Can fruiting plants control animal behaviour and seed dispersal distance?

Behaviour ◽

10.1163/1568539x-00003205 ◽

2015 ◽

Vol 152 (3-4) ◽

pp. 359-374 ◽

Cited By ~ 4

Author(s):

David Beaune ◽

François Bretagnolle ◽

Loïc Bollache ◽

Gottfried Hohmann ◽

Barbara Fruth

Keyword(s):

Seed Dispersal ◽

Plant Species ◽

Fruit Quality ◽

Population Biology ◽

Dispersal Distance ◽

Feeding Time ◽

Fruit Traits ◽

Dispersal Distances ◽

Dispersal Vector ◽

Seed Dispersal Distance

In an Afrotropical forest, we tested the hypothesis that fleshy-fruit plants with interspecific differences in fruit quality and quantity affect ranging behaviour of their seed dispersal vector. If fruiting plants could affect their dispersal vector, the plants also affect their seed dispersal distance and eventually their plant population biology. From 2007 to 2011, we measured seed transport by georeference daily bonobo group movements via GPS. Seed dispersal distance was estimated with mechanistic model, using 1200 georeferenced dispersal events and the average seed transit time through bonobo (24.00 h). We compared dissemination for eight plant species that deal with this trade-off: attracting dispersers by means of fruit quality/quantity versus retaining them in the patch because of the same quality/quantity value that attracted them. Because fruit traits of these eight species were different, we expected a difference in seed dispersal distance. Surprisingly, seed dispersal distances induced by bonobos were not affected by fruit traits. Although fruit nutrient contents, abundance and average patch feeding duration differed between plant species, patch feeding time was not related to subsequent dispersal distances. The apes’ dispersal distance survey gave an average dispersal distance estimated of 1332 ± 24 m from the parent plant (97.9% > 100 m). To conclude, feeding time invested in the patch, fruit quality and abundance had no apparent effect on bonobo seed dispersal distance. The possible effects in plant population biology are discussed.

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Seed-dispersal distributions by trumpeter hornbills in fragmented landscapes

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2010.2383 ◽

2011 ◽

Vol 278 (1716) ◽

pp. 2257-2264 ◽

Cited By ~ 78

Author(s):

Johanna Lenz ◽

Wolfgang Fiedler ◽

Tanja Caprano ◽

Wolfgang Friedrichs ◽

Bernhard H. Gaese ◽

...

Keyword(s):

Seed Dispersal ◽

Agricultural Landscape ◽

Dispersal Distance ◽

Climatic Conditions ◽

Fragmented Landscape ◽

Long Distance ◽

Frugivorous Birds ◽

Fragmented Landscapes ◽

Habitat Patches ◽

Dispersal Distances

Frugivorous birds provide important ecosystem services by transporting seeds of fleshy fruited plants. It has been assumed that seed-dispersal kernels generated by these animals are generally leptokurtic, resulting in little dispersal among habitat fragments. However, little is known about the seed-dispersal distribution generated by large frugivorous birds in fragmented landscapes. We investigated movement and seed-dispersal patterns of trumpeter hornbills ( Bycanistes bucinator ) in a fragmented landscape in South Africa. Novel GPS loggers provide high-quality location data without bias against recording long-distance movements. We found a very weakly bimodal seed-dispersal distribution with potential dispersal distances up to 14.5 km. Within forest, the seed-dispersal distribution was unimodal with an expected dispersal distance of 86 m. In the fragmented agricultural landscape, the distribution was strongly bimodal with peaks at 18 and 512 m. Our results demonstrate that seed-dispersal distributions differed when birds moved in different habitat types. Seed-dispersal distances in fragmented landscapes show that transport among habitat patches is more frequent than previously assumed, allowing plants to disperse among habitat patches and to track the changing climatic conditions.

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Dispersal distances and migration rates at the arctic treeline in Siberia – a genetic and simulation based study

10.5194/bg-2018-267 ◽

2018 ◽

Cited By ~ 1

Author(s):

Stefan Kruse ◽

Alexander Gerdes ◽

Nadja J. Kath ◽

Laura S. Epp ◽

Kathleen R. Stoof-Leichsenring ◽

...

Keyword(s):

Seed Dispersal ◽

Parentage Analysis ◽

Dispersal Distance ◽

Climate Feedback ◽

The Arctic ◽

Long Distance ◽

North Central ◽

Central Siberia ◽

Migration Rates ◽

Dispersal Distances

Abstract. A strong temperature increase in the Arctic is expected to lead to latitudinal treeline shift. This tundra-taiga turnover would cause a positive vegetation-climate feedback due to albedo decrease. However, reliable estimates of tree migration rates are currently lacking due to the complex processes involved in forest establishment, which depend strongly on seed dispersal. We aim to fill this gap using LAVESI, an individual-based and spatially explicit Larix vegetation simulator. LAVESI was designed to simulate plots within homogeneous forests. Here, we improve the implementation of the seed dispersal function via field-based investigations. We inferred the effective seed dispersal distances of a typical open forest stand on the southern Taymyr Peninsula (north-central Siberia) from genetic parentage analysis using eight highly polymorphic nuclear microsatellite loci. The parentage analysis gives effective seed dispersal distances (median ~ 10 m) close to the seed parents. A comparison between simulated and observed effective seed dispersal distances reveals an overestimation of recruits close to the releasing tree and a shorter dispersal distance generally. We thus adapted our model and used it to simulate south-to-north transects: a slow-moving treeline front was revealed. The colonisation of the tundra areas was assisted by occasional long-distance seed dispersal events beyond the treeline area. The treeline (~ 1 tree ha−1) advanced by ~ 1.6 m yr−1, whereas the forest line (~ 100 trees ha−1) advanced by only ~ 0.6 m yr−1. We conclude that the treeline in north-central Siberia currently lags behind the current strong warming and will continue to lag in the near future.

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How far might plant-eating dinosaurs have moved seeds?

Biology Letters ◽

10.1098/rsbl.2020.0689 ◽

2021 ◽

Vol 17 (1) ◽

pp. 20200689

Author(s):

George L. W. Perry

Keyword(s):

Seed Dispersal ◽

Body Mass ◽

Dispersal Distance ◽

Movement Speed ◽

Gut Contents ◽

Allometric Relationship ◽

Seed Retention ◽

Dispersal Distances ◽

Seed Retention Time ◽

Seed Dispersal Distance

Fossilized gut contents suggest that seeds consumed by dinosaurs may have remained intact in their stomachs, and since seed dispersal distance increases with body-mass in extant vertebrates, dinosaurs may have moved seeds long distances. I simulated seed dispersal by dinosaurs across body-masses from 1 × 10 1 to 8 × 10 4 kg using allometric random walk models, informed by relationships between (i) body-mass and movement speed, and (ii) body-mass and seed retention time. Seed dispersal distances showed a hump-shaped relationship with body-mass, reflecting the allometric relationship between maximum movement speed and body-mass. Across a range of assumptions and parameterizations, the simulations suggest that plant-eating dinosaurs could have dispersed seeds long distances.

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Primary seed dispersal by the black-and-white ruffed lemur (Varecia variegata) in the Manombo forest, south-east Madagascar

Journal of Tropical Ecology ◽

10.1017/s0266467411000198 ◽

2011 ◽

Vol 27 (5) ◽

pp. 529-538 ◽

Cited By ~ 12

Author(s):

Kara L. Moses ◽

Stuart Semple

Keyword(s):

Seed Dispersal ◽

Dispersal Patterns ◽

Black And White ◽

Structure And Dynamics ◽

Gut Passage ◽

Faecal Analysis ◽

Varecia Variegata ◽

Ranging Behaviour ◽

Dispersal Distances ◽

Ruffed Lemur

Abstract:Seed dispersal is a pivotal ecological process but remains poorly understood on Madagascar, where lemurs are key dispersers. The black-and-white ruffed lemur (Varecia variegata) possesses many behavioural and ecological attributes potentially conducive to effective seed dispersal, but no studies have investigated dispersal patterns in this species. This 3-mo study quantified aspects of the primary seed dispersal patterns generated by two Varecia variegata groups (7 individuals). Feeding and ranging behaviour was quantified using behavioural observation (345.6 h), dispersal quantity and seed identity was determined by faecal analysis, and 10-wk germination trials tested effects of gut passage on germination of four species. Individual lemurs dispersed an estimated 104 seeds d−1, of 40 species. Most seeds were large (>10 mm); the largest was 42 mm long. Gut passage was rapid (mean 4.4 h) and generally increased germination speed and success. Mean and maximum inferred dispersal distances were 180 and 506 m respectively; low compared with many anthropoids, but possibly typical of lemurs. Though limited by a short study period, results suggest that the ruffed lemur is an effective disperser of seeds and possibly a critical disperser of large-seeded species which other frugivores cannot swallow. Loss of large-bodied seed dispersers such as Varecia variegata may have far-reaching ecological consequences including impacts on forest structure and dynamics.

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Long-distance wind dispersal of tree seeds

Canadian Journal of Botany ◽

10.1139/b95-113 ◽

1995 ◽

Vol 73 (7) ◽

pp. 1036-1045 ◽

Cited By ~ 75

Author(s):

D. F. Greene ◽

E. A. Johnson

Keyword(s):

Seed Dispersal ◽

Conservation Biology ◽

Plant Conservation ◽

Dispersal Distance ◽

Wind Dispersal ◽

Source Strength ◽

Long Distance ◽

Model Predictions ◽

Tree Seeds ◽

The Relationship

Long-distance seed dispersal figures prominently in most plant conservation biology arguments, yet we possess little more than anecdotes concerning the relationship among deposition (seeds/m2), source strength (seeds/m2), and distance. In this paper we derive two simple models for long-distance deposition. The models are tested at the scale of 100–1600 m from the source and found to be within 5-fold of the observed deposition. There is no discernable decline in deposition for the range 300–1600 m. While we hesitate to extend model predictions to greater distances, both the models and the empirical results allow us to assert that rare wind-dispersed species in woodlots (dispersal distance around 1 km) are effectively isolated from one another at the temporal scale of 1000 years. Key words: plant conservation biology, wind dispersal of seeds, metapopulations.

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