Wild boars as seed dispersal agents of exotic plants from agricultural lands to conservation areas

Abstract Some large-seeded plants lack effective seed dispersal agents when they are introduced as ornamental plants to new areas, but can rapidly colonize a landscape if seed dispersal functions are restored. We examined whether Gopherus polyphemus (Gopher Tortoise) facilitated the spread of Chrysobalanus icaco (Cocoplum; Chrysobalanaceae) over a 14-year period in a suburban nature preserve (in Jupiter, FL, USA) by: (i) comparing germination patterns among gut-passed, hand-depulped and whole fruit treatments, and (ii) testing hypotheses about environmental predictors of the spatial distribution of C. icaco, including information about G. polyphemus movement pathways and burrow locations. While we did not find a significant difference in the total proportion of C. icaco seeds that germinated in each treatment, time to event analysis revealed that seeds that were found in faeces germinated significantly earlier than seeds that were hand-depulped or that were planted as whole fruits, supporting a lone scarification effect. Point process modeling revealed that the density of C. icaco bushes was higher near G. polyphemus movement pathways and was lower inside Serenoa repens (Saw Palmetto) patches, supporting a positive effect of tortoise movement patterns on plant distributions. The density of C. icaco increased from west to east, consistent with westward dispersal from the four founder bushes on the east side of the study area. After removal of outliers, we also detected a negative association between C. icaco spatial density and G. polyphemus burrow density that was presumably explained by the fact that seeds defecated deep within burrows were unlikely to germinate and establish without secondary movement. The results suggest that G. polyphemus contributed to the rapid dispersal of C. icaco by scatter dispersal of seeds (via faeces) in areas where tortoises were active and that movement pathways provided suitable conditions for colonization. The spread of C. icaco by G. polyphemus over a relatively short period of time provides a valuable window into the earliest stages of the colonization process and further supports the role of Chelonians as effective seed dispersal agents for large-seeded plants.

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Interspecific synchrony and asynchrony in the fruiting phenologies of congeneric bird-dispersed plants in Panama

Journal of Tropical Ecology ◽

10.1017/s0266467499000760 ◽

1999 ◽

Vol 15 (2) ◽

pp. 213-227 ◽

Cited By ~ 67

Author(s):

Brigitte Poulin ◽

S. Joseph Wright ◽

Gaëtan Lefebvre ◽

Osvaldo Calderón

Keyword(s):

Seed Dispersal ◽

Bird Species ◽

Null Model ◽

High Potential ◽

Faecal Samples ◽

Critical Resource ◽

Resident Populations ◽

Dispersal Agents ◽

Central Panama ◽

Temporal Overlap

Plants potentially compete for seed dispersal. Selection may favour temporally segregated fruiting phenologies to minimize this competition and also to maintain resident populations of dispersal agents. Alternatively, selection may favour temporally aggregated fruiting phenologies when the effectiveness of seed dispersal agents varies seasonally or when large, synchronous fruit displays enhance dispersal. These evolutionary scenarios assume that plants share seed dispersal agents. This assumption and temporal overlap in fruiting phenologies were evaluated for the Miconia and Psychotria of central Panama. These two genera accounted for 18 and 27%, respectively, of 1096 fleshy fruits found in regurgitation or faecal samples taken from 2054 birds of 103 species netted in the forest understorey. Two species of manakins accounted for 62% (123/200) of all Miconia fruit taken. Three species of manakins and three species of migratory thrushes accounted for 97% (282/292) of all Psychotria fruits taken. There is a high potential for intrageneric competition for seed dispersal for both plant genera. Null model analyses showed that the fruiting phenologies of Miconia (14 species) are segregated in time, while fruiting of Psychotria (21 species) is highly aggregated. The Miconia were found in up to 24% of the diet samples for the two manakin species, suggesting that Miconia may be a critical resource for both species. The Psychotria fruited when the diversity of understorey fruits was greatest, suggesting a high potential for both intra- and extrageneric competition. The abundance and nomadism of the six bird species that consumed most Psychotria fruit peaked when the Psychotria fruited, supporting the enhancement hypothesis.

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Seed dispersal agents of two Ficus species in a disturbed tropical forest

ORNITHOLOGICAL SCIENCE ◽

10.2326/osj.2.119 ◽

2003 ◽

Vol 2 (2) ◽

pp. 119-125 ◽

Cited By ~ 2

Author(s):

Kelvin S.-H. Peh ◽

Fong Lin Chong

Keyword(s):

Seed Dispersal ◽

Tropical Forest ◽

Dispersal Agents

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Cone and seed traits of two Juniperus species influence roles of frugivores and scatter-hoarding rodents as seed dispersal agents

Acta Oecologica ◽

10.1016/j.actao.2017.09.012 ◽

2017 ◽

Vol 85 ◽

pp. 93-103 ◽

Cited By ~ 9

Author(s):

Lindsay A. Dimitri ◽

William S. Longland ◽

Stephen B. Vander Wall

Keyword(s):

Seed Dispersal ◽

Seed Traits ◽

Scatter Hoarding ◽

Dispersal Agents

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Evidence of frugivory and seed dispersal in Oligocene tortoises from South Dakota

Geological Magazine ◽

10.1017/s0016756813000459 ◽

2013 ◽

Vol 150 (6) ◽

pp. 1143-1149 ◽

Cited By ~ 2

Author(s):

ALAN O. MARRON ◽

JASON R. MOORE

Keyword(s):

Seed Dispersal ◽

South Dakota ◽

Correct Placement ◽

Reliable Evidence ◽

Dispersal Agents

AbstractFossilized hackberry (Celtis) seeds were found within the shells of twoStylemysindividuals excavated from Oligocene sediments from South Dakota. The presence ofin situskeletal elements indicates that the tortoises were buried without extensive disarticulation. Abiotic transport of the seeds into the carcasses is unlikely given the anatomically correct placement of both skeletal elements and seeds and the comparative settling velocities of the encasing sediment versus modernCeltisseeds. Ecological evidence from modernCeltisandStylemysanalogues suggests that tortoises are commonly seed dispersal agents. The fossils are therefore interpreted as enterolites, providing the oldest reliable evidence of tortoise frugivory.

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Macaques as Seed Dispersal Agents in Asian Forests: A Review

International Journal of Primatology ◽

10.1007/s10764-018-0045-7 ◽

2018 ◽

Vol 39 (3) ◽

pp. 356-376 ◽

Cited By ~ 2

Author(s):

Yamato Tsuji ◽

Hsiu-Hui Su

Keyword(s):

Seed Dispersal ◽

Dispersal Agents

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Dispersal of seeds of Hymenaea courbaril (Fabaceae) in a logged rain forest in the Peruvian Amazonian

Acta Amazonica ◽

10.1590/s0044-59672004000200014 ◽

2004 ◽

Vol 34 (2) ◽

pp. 251-259 ◽

Cited By ~ 12

Author(s):

David L. Gorchov ◽

Jorge M. Palmeirim ◽

Cesar F. Ascorra

Keyword(s):

Seed Dispersal ◽

Rain Forest ◽

Forest Edge ◽

Dispersal Distance ◽

Similar Species ◽

Removal Rates ◽

Hymenaea Courbaril ◽

Dispersal Agents

Seed dispersal of Hymenaea courbaril was studied by following the fate of 585 seeds embedded with small magnets and set in displays in and near a logged strip in rain forest in the Peruvian Amazonian. Mammals took fruits from all displays, which were located in the forest, edge, and cleared strip. Overall removal rates were low - a median of 8.1 fruits / month from displays maintained with 8-10 fruits - but were higher in August than in earlier months. Most fruits were dropped near the display or had their seeds eaten, but > 13% were successfully dispersed. Most of the dispersed seeds were buried, which increases probability of germination. Maximum dispersal distance of live seeds was 12.1 m (median 3.1 m), but other magnets were transported up to 34 m, indicating seeds were dispersed further, but then eaten. Acouchies (most likely Myoprocta pratti) and agoutis (Dasyprocta fuliginosa) were apparently the main dispersal agents. Dispersal of seeds from the forest into the logged strip was rare, suggesting that although rodents disperse H. courbaril, they cannot be relied on for the reseeding this and similar species in recent clearings.

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Balanites wilsoniana: elephant dependent dispersal?

Journal of Tropical Ecology ◽

10.1017/s0266467400006519 ◽

1992 ◽

Vol 8 (3) ◽

pp. 275-283 ◽

Cited By ~ 73

Author(s):

Lauren J. Chapman ◽

Colin A. Chapman ◽

Richard W. Wrangham

Keyword(s):

Seed Dispersal ◽

Seedling Survival ◽

Loxodonta Africana ◽

Forest Tree ◽

Vital Role ◽

Insect Damage ◽

Scatter Hoarding ◽

Forest Elephants ◽

Dispersal Agents ◽

Time Of Collection

ABSTRACTThis study demonstrates that forest elephants (Loxodonta africana) play a key role as seed dispersal agents for the upper canopy forest tree, Balanites wilsoniana. Seed that passed through elephants had a much greater probability of germinating (50.7%) than seeds from fruits eollected directly from the tree (3%). Of 515 seeds that were collected from under parent trees, 89.1% were rotten at the time of collection, 2.6% had been eaten by forest pigs, 2.8% had been killed by squirrels, and 0.7% had been killed by insect damage. The remaining 4.8% of the seeds were still alive. In 150 hours of focal observations on B. wilsoniana trees, two fruits were seen to be destroyed by squirrels, no fruits were seen to be consumed by potential dispersers, and no evidence of scatter hoarding was found. Experimental seedling stations placed out under parent trees and away from parent trees indicated no significant effect of dispersal on seedling survival. Although elephants are not essential for the successful germination of B. wilsoniana seeds, they do greatly increase probability of germination and play a vital role in their dispersal, suggesting that this is a highly interdependent plant-animal seed dispersal system.

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Frugivory and seed dispersal in Cymbopetalum baillonii (Annonaceae) at Los Tuxtlas, Mexico

Journal of Tropical Ecology ◽

10.1017/s0266467400002650 ◽

1988 ◽

Vol 4 (2) ◽

pp. 157-172 ◽

Cited By ~ 41

Author(s):

Rosamond Coates-Estrada ◽

Alejandro Estrada

Keyword(s):

Seed Dispersal ◽

Field Experiments ◽

Narrow Range ◽

Fruit Production ◽

Foraging Activity ◽

Los Tuxtlas ◽

Parent Tree ◽

Adult Trees ◽

Dispersal Agents ◽

Fruit Dehiscence

ABSTRACTFruit production, frugivore foraging activity and seed dispersal was studied at 10 Cymbopetalum baillonii (Annonaceae) trees during an entire fruiting season. Fruits dehisced during the first six months of the year offer to potential dispersal agents a package of 8–24 arillate seeds. Insects and fungi, however, killed up to 14% of the seeds potentially available for dispersal before fruit dehiscence. Visitation by 24 species of birds and one mammal to the trees closely followed the availability of arillate seeds. The foraging activity of Peromyscus and Heteromys rodents accounted for ≥ 80% mortality of the seeds deposited under the crown of the parent tree. Among those seedlings that became established under the crown mortality was ≥ 90% after 12 months. Seeds dispersed under conspecific fruiting trees experienced intense predation by vertebrates. Field experiments showed that seeds and seedlings planted ≥ 30 m away from adult trees survived significantly longer than those planted under the crown and at distances ≤ 30 m. An unequivocal advantage to dispersal away from the tree and under allospecific trees was evident from the data. A very narrow range of frugivores (N = 8 species) accounted for the quality component of dispersal services to the trees. The tree with the lowest animal visitation and fruit crop was the most efficient in the dispersal of its seeds.

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