An experimental test of the capacity for long-distance dispersal of freshwater diatoms adhering to waterfowl plumage

Waterfowl are potential long-distance dispersal vectors for aquatic microbes such as diatoms, but experimental evidence is scarce. We conducted an experiment designed to emulate diatom dispersal via adherence to waterfowl, and to evaluate the effects of humidity and transport duration on potential dispersal success. We dipped individual mallard breast feathers in a pure benthic diatom culture (Nitzschia pusilla Grunow), then subjected them to one of four relative humidity levels (RH; from ca. 8% to 88%) crossed with one of four transport durations (10, 60, 120, 240 minutes) within a chamber through which air was passed continuously, mimicking light wind. We then placed the feather on sterile growth medium. After two weeks we used spectrofluorometry to detect diatom growth and thus diatom viability. A logistic regression on viability revealed a significant interaction between transport duration and RH: the negative effect of duration was strongest under lower RH conditions, but under high RH (88%) the probability of being viable was moderate to high regardless of transport duration. Importantly, even after 4 hours, the probability of being viable was predicted to be 0.45 (95% confidence interval: 0.18 to 0.75). We then placed our findings in the geographic context of the central waterfowl migration flyway in North America, and specifically Nebraska, South Dakota, and North Dakota, for which sufficient data were available to enable geospatial predictions of potential mallard-borne diatom dispersal. Combined with published data about (i) mallard flight speeds, (ii) the geographic distribution of surface waters and of N. pusilla, and (iii) daytime RH during the months of April through June, our model predicted high probabilities of potential dispersal among the region’s suitable water bodies.

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Larvae from deep-sea methane seeps disperse in surface waters

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2013.3276 ◽

2014 ◽

Vol 281 (1786) ◽

pp. 20133276 ◽

Cited By ~ 49

Author(s):

Shawn M. Arellano ◽

Ahna L. Van Gaest ◽

Shannon B. Johnson ◽

Robert C. Vrijenhoek ◽

Craig M. Young

Keyword(s):

Surface Waters ◽

Deep Sea ◽

Direct Evidence ◽

Euphotic Zone ◽

Cold Seep ◽

Long Distance Dispersal ◽

Methane Seeps ◽

Long Distance ◽

Western Atlantic ◽

Species Complexes

Many species endemic to deep-sea methane seeps have broad geographical distributions, suggesting that they produce larvae with at least episodic long-distance dispersal. Cold-seep communities on both sides of the Atlantic share species or species complexes, yet larval dispersal across the Atlantic is expected to take prohibitively long at adult depths. Here, we provide direct evidence that the long-lived larvae of two cold-seep molluscs migrate hundreds of metres above the ocean floor, allowing them to take advantage of faster surface currents that may facilitate long-distance dispersal. We collected larvae of the ubiquitous seep mussel “Bathymodiolus” childressi and an associated gastropod, Bathynerita naticoidea , using remote-control plankton nets towed in the euphotic zone of the Gulf of Mexico. The timing of collections suggested that the larvae might disperse in the water column for more than a year, where they feed and grow to more than triple their original sizes. Ontogenetic vertical migration during a long larval life suggests teleplanic dispersal, a plausible explanation for the amphi-Atlantic distribution of “B.” mauritanicus and the broad western Atlantic distribution of B. naticoidea . These are the first empirical data to demonstrate a biological mechanism that might explain the genetic similarities between eastern and western Atlantic seep fauna.

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Spatial heterogeneities of human-mediated dispersal vectors accelerate the range expansion of invaders with source–destination-mediated dispersal

Scientific Reports ◽

10.1038/s41598-020-78633-3 ◽

2020 ◽

Vol 10 (1) ◽

Author(s):

Daisuke Takahashi ◽

Young-Seuk Park

Keyword(s):

Invasive Species ◽

Population Dynamics ◽

Range Expansion ◽

Human Activities ◽

Invasion Biology ◽

Spatial Variations ◽

Long Distance Dispersal ◽

Long Distance ◽

Dispersal Vectors ◽

Underlying Processes

AbstractRapid range expansions of invasive species are a major threat to ecosystems. Understanding how invasive species increase their habitat ranges and how environmental factors, including intensity of human activities, influence dispersal processes is an important issue in invasion biology, especially for invasive species management. We have investigated how spatially heterogeneous factors influence range expansion of an invasive species by focusing on long-distance dispersal, which is frequently assisted by human activities. We have developed models varying two underlying processes of a dispersal event. These events are described by source and destination functions that determine spatial variations in dispersal frequency and the probability of being a dispersal destination. Using these models, we investigated how spatially heterogeneous long-distance dispersal influences range expansion. We found that: (1) spatial variations in the destination function slow down late population dynamics, (2) spatial variations in the source function increase the stochasticity of early population dynamics, and (3) the speed of early population dynamics changes when both the source and the destination functions are spatially heterogeneous and positively correlated. These results suggest an importance of spatial heterogeneity factors in controlling long-distance dispersal when predicting the future spread of invasive species.

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RESEARCH NOTES: LONG-DISTANCE DISPERSAL BY A SUBADULT MALE COUGAR FROM THE BLACK HILLS, SOUTH DAKOTA

Journal of Wildlife Management ◽

10.2193/0022-541x(2005)069[0818:ldbasm]2.0.co;2 ◽

2005 ◽

Vol 69 (2) ◽

pp. 818-820 ◽

Cited By ~ 29

Author(s):

DANIEL J. THOMPSON ◽

JONATHAN A. JENKS

Keyword(s):

South Dakota ◽

Black Hills ◽

Long Distance Dispersal ◽

Long Distance ◽

Subadult Male

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Resurrection and typification of Elatine campylosperma (Elatinaceae), a long-forgotten waterwort species

PeerJ ◽

10.7717/peerj.4913 ◽

2018 ◽

Vol 6 ◽

pp. e4913

Author(s):

Attila Takács ◽

Attila Molnár V. ◽

Balázs A. Lukács ◽

Timea Nagy ◽

Ádám Lovas-Kiss ◽

...

Keyword(s):

Habitat Preferences ◽

Distribution Area ◽

Published Data ◽

Herbarium Specimens ◽

Long Distance Dispersal ◽

Long Distance ◽

Faecal Samples ◽

Fulica Atra ◽

Label Information

The name Elatine campylosperma Seub. is generally treated as one of the synonyms of E. macropoda Guss. However, recent morphological, phylogenetic and karyological studies indicate that this judgement should be revised. In the present paper we typify the name E. campylosperma, review its taxonomic history and provide a thorough description, with compilation of previously published data and our new measurements from in vitro cultures. Based on our herbarium survey, we outline its Atlantic-Mediterranean distribution area (Spain, France, Italy, Greece, Turkey and Algeria). Habitat preferences are summarized from our field observations, water quality measurements and the label information of the herbarium specimens examined. Intact E. campylosperma seeds were found in faecal samples of the Eurasian Coot (Fulica atra L.) in southern Spain and two of them were germinated, suggesting that E. campylosperma has a capacity for long distance dispersal via endozoochory.

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