scholarly journals Special delivery: scavengers direct seed dispersal towards ungulate carcasses

2018 ◽  
Vol 14 (8) ◽  
pp. 20180388 ◽  
Author(s):  
S. M. J. G. Steyaert ◽  
S. C. Frank ◽  
S. Puliti ◽  
R. Badia ◽  
M. P. Arnberg ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Seed Dispersal ◽  
Vegetative Reproduction ◽  
Keystone Species ◽  
Alpine Tundra ◽  
Small Scale ◽  
Plant Seeds ◽  
Plant Life ◽  
Viable Seeds

Cadaver decomposition islands around animal carcasses can facilitate establishment of various plant life. Facultative scavengers have great potential for endozoochory, and often aggregate around carcasses. Hence, they may disperse plant seeds that they ingest across the landscape towards cadaver decomposition islands. Here, we demonstrate this novel mechanism along a gradient of wild tundra reindeer carcasses. First, we show that the spatial distribution of scavenger faeces (birds and foxes) was concentrated around carcasses. Second, faeces of the predominant scavengers (corvids) commonly contained viable seeds of crowberry, a keystone species of the alpine tundra with predominantly vegetative reproduction. We suggest that cadaver decomposition islands function as endpoints for directed endozoochory by scavengers. Such a mechanism could be especially beneficial for species that rely on small-scale disturbances in soil and vegetation, such as several Nordic berry-producing species with cryptic generative reproduction.

scholarly journals Endozoochory by mallard in New Zealand: what seeds are dispersed and how far?

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e4811 ◽  
Author(s):  
Riley D. Bartel ◽  
Jennifer L. Sheppard ◽  
Ádám Lovas-Kiss ◽  
Andy J. Green
Keyword(s):  
New Zealand ◽  
Seed Dispersal ◽  
Plant Species ◽  
Dispersal Distance ◽  
Terrestrial Plants ◽  
Indigenous Status ◽  
Plant Seeds ◽  
Faecal Samples ◽  
Viable Seeds ◽  
Study Sites

In Europe and North America waterfowl are major dispersers of aquatic and terrestrial plants, but in New Zealand their role has yet to be investigated. Mallards were introduced to New Zealand in the late 1800s, and today they are the most abundant and widespread waterfowl in the country. To assess seed dispersal, we radiomarked 284 female mallards from two study sites during the pre-breeding (June–August) and breeding (August–December) periods in 2014–2015, and examined movements that occurred within 24, 48 or 72 h when seed dispersal by endozoochory is considered likely. During June and July 2015, we collected 29 faecal samples from individual female mallards during radiomarking and 24 samples from mallard flocks. We recovered 69 intact seeds from the faecal samples and identified 12 plant taxa. Of the plant seeds identified and dispersed by mallards in this study, 40% were members of the Asteraceae family, nine plant species were alien to New Zealand, and the indigenous-status of three unidentified taxa could not be determined. Two taxa (and 9% of seeds) were germinated following gut passage: an unidentified Asteraceae andSolanum nigrum. During the pre-breeding and breeding periods, movement of females within 24 h averaged 394 m (SD = 706 m) and 222 m (SD = 605 m) respectively, with maximum distances of 3,970 m and 8,028 m. Maxima extended to 19,230 m within 48 h. Most plant species recorded are generally assumed to be self-dispersed or dispersed by water; mechanisms that provide a much lower maximum dispersal distance than mallards. The ability of mallards to disperse viable seeds up to 19 km within 48 h suggests they have an important and previously overlooked role as vectors for a variety of wetland or grassland plant species in New Zealand.

Impact of the Small-Scale Spatial Distribution of Dust Particles on the Chemical Evolution of the Diffuse Interstellar Medium

2020 ◽  
Vol 64 (8) ◽  
pp. 693-710
Author(s):  
V. A. Sokolova ◽  
A. I. Vasyunin ◽  
A. B. Ostrovskii ◽  
S. Yu. Parfenov
Keyword(s):  
Spatial Distribution ◽  
Interstellar Medium ◽  
Chemical Evolution ◽  
Dust Particles ◽  
Small Scale

scholarly journals Small-scale spatial distribution of COVID-19-related excess mortality

MethodsX ◽  
2021 ◽  
Vol 8 ◽  
pp. 101257
Author(s):  
Dino Gibertoni ◽  
Francesco Sanmarchi ◽  
Kadjo Yves Cedric Adja ◽  
Davide Golinelli ◽  
Chiara Reno ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Excess Mortality ◽  
Small Scale

scholarly journals Seed dispersal of Solanum thomasiifolium Sendtner (Solanaceae) in the Linhares Forest, Espírito Santo state, Brazil

2009 ◽  
Vol 23 (4) ◽  
pp. 1171-1179 ◽  
Author(s):  
João Vasconcellos-Neto ◽  
Lidiamar Barbosa de Albuquerque ◽  
Wesley Rodrigues Silva
Keyword(s):  
Seed Dispersal ◽  
Control Bird ◽  
Brazilian Coast ◽  
Espírito Santo ◽  
Bird Droppings ◽  
Fruit Productivity ◽  
Habitat Colonization ◽  
Viable Seeds ◽  
Espirito Santo ◽  
And Control

The aim of this study was to analyse seed dispersal and establishment of Solanum thomasiifolium in an area of "nativo" vegetation in Espirito Santo state on the southeastern Brazilian coast. Ten species of birds, the crab-eating fox (Cerdocyon thous), and one species of lizard (Tropidurus torquatus) fed on S. thomasiifolium fruits and dispersed viable seeds in their faeces. The proportional contribution of each of these groups to seed dispersal was 77% (birds), 19% (crab-eating fox) and 4% (lizards). Ants also contributed to seed dispersal. More seeds were deposited in vegetation islands than in the surrounding open areas. Germination rates of seeds collected directly from fruit (control), bird droppings, the faeces of crab-eating foxes and lizards were, respectively, 64, 64, 53, and 80 %. Differences among these rates were all significant, except between birds and control. Lizards were important as seed carriers between nearby islands and they expelled a higher proportion of viable seeds. Birds and the crab-eating foxes did not enhance seed germination, but promoted seed dispersal over a wider area. Plant architecture, fruit productivity, fruit characteristics and the diversity of frugivores are important for the success of S. thomasiifolium in habitat colonization.

scholarly journals Supporting Spatial Management of Data-Poor, Small-Scale Fisheries With a Bayesian Approach

2021 ◽  
Vol 8 ◽  
Author(s):  
Jennifer Rehren ◽  
Maria Grazia Pennino ◽  
Marta Coll ◽  
Narriman Jiddawi ◽  
Christopher Muhando
Keyword(s):  
Spatial Distribution ◽  
Marine Conservation ◽  
Environmental Drivers ◽  
Small Scale ◽  
Target Species ◽  
Short Term ◽  
Conservation Areas ◽  
Bayesian Hierarchical ◽  
Small Scale Fisheries ◽  
Spatial Management

Marine conservation areas are an important tool for the sustainable management of multispecies, small-scale fisheries. Effective spatial management requires a proper understanding of the spatial distribution of target species and the identification of its environmental drivers. Small-scale fisheries, however, often face scarcity and low-quality of data. In these situations, approaches for the prioritization of conservation areas need to deal with scattered, biased, and short-term information and ideally should quantify data- and model-specific uncertainties for a better understanding of the risks related to management interventions. We used a Bayesian hierarchical species distribution modeling approach on annual landing data of the heavily exploited, small-scale, and data-poor fishery of Chwaka Bay (Zanzibar) in the Western Indian Ocean to understand the distribution of the key target species and identify potential areas for conservation. Few commonalities were found in the set of important habitat and environmental drivers among species, but temperature, depth, and seagrass cover affected the spatial distribution of three of the six analyzed species. A comparison of our results with information from ecological studies suggests that our approach predicts the distribution of the analyzed species reasonably well. Furthermore, the two main common areas of high relative abundance identified in our study have been previously suggested by the local fisher as important areas for spatial conservation. By using short-term, catch per unit of effort data in a Bayesian hierarchical framework, we quantify the associated uncertainties while accounting for spatial dependencies. More importantly, the use of accessible and interpretable tools, such as the here created spatial maps, can frame a better understanding of spatio-temporal management for local fishers. Our approach, thus, supports the operability of spatial management in small-scale fisheries suffering from a general lack of long-term fisheries information and fisheries independent data.

Spatial distribution of Antarctic shrimps (Crustacea: Decapoda) by underwater photography

1991 ◽  
Vol 3 (4) ◽  
pp. 363-369 ◽  
Author(s):  
Julian Gutt ◽  
M. Gorny ◽  
W. Arntz
Keyword(s):  
Spatial Distribution ◽  
Continental Shelf ◽  
Weddell Sea ◽  
Small Scale ◽  
Frequency Distributions ◽  
South Eastern ◽  
Direct Observations ◽  
Underwater Photography ◽  
Dispersion Patterns ◽  
Eastern Weddell Sea

Three species of shrimps (Notocrangon antarcticus, Chorismus antarcticus, Nematocarcinus lanceopes) were investigated in the south-eastern Weddell Sea using of underwater photography. Maximum densities of c. 100 specimens per 100 m2 were found for N. antarcticus on the continental shelf (200–600 m) and for N. lanceopes on the slope (800–1200 m). Small-scale dispersion patterns and size-frequency distributions were analyzed within dense concentrations. These direct observations indicate that the behaviour of the three species is adapted to different habitats with Chorismus distribution correlated with that of sponges and Notocrangon with base sediment.

Plants

2002 ◽  
Author(s):  
Martin L. Cody
Keyword(s):  
Plant Diversity ◽  
Gulf Of California ◽  
Small Scale ◽  
Rock Masses ◽  
Introductory Section ◽  
Plant Life ◽  
Coastal Cliffs ◽  
Sea Of Cortes ◽  
Pachycereus Pringlei

This chapter deals with the general features of plant diversity and distribution on the Sea of Cortés islands and to a lesser extent with adaptive features of plants such as morphology and phenology. This review is based mainly on the plant lists in appendixes 4.1-4.5 describing the island floras, endemics, and relicts. In our interpretations of these lists we draw from various floristic, systematic, and distributional works that pertain to the Gulf of California region and beyond. After an introductory section, we work from broader biogeographical questions to matters that have more local, specific, or taxonomically restricted perspectives. There must be few experiences in the biologist’s world to compare with approaching a “new” island by boat. The ingredients are adventure and suspense, mystery and perhaps even a little danger. There are feelings of discoveries to be made, knowledge to be extended, curiosity to be both piqued and satisfied. Such feelings are shared not only among natural historians but by any adventurous and curious traveler; the more difficult the island is to reach, the keener the excitement of the visit. The islands in the Sea of Cortés would seem ideally qualified to generate this sort of bioadventurism. They are mostly uninhabited and have been little explored biologically, and the mounting of small-scale expeditions to successfully reach (and leave) the islands is not always a trivial matter. First appearing as blurry, near-colorless breaks between the unrelenting blue of gulf and sky, the islands leave early impressions of abrupt topography and a seeming lack of vegetation. The dull-green smudge of plant life on foothill outwash fans and in the arroyos eventually becomes apparent, but almost up to the point of a landing the islands preserve the impression of rock masses broken only occasionally by bajadas on which a few cardons (Pachycereus pringlei) are conspicuous. Islands larger than a few square kilometers have well-developed drainage courses that reach the coasts as dry arroyos and provide breaks in the generally steep coastal cliffs. The beaches where the larger arroyos reach the coast are logical landing points, and here the visitor gets the first close look at the vegetation.

scholarly journals Effect of desiccation temperature on viability of immature dandelion (Taraxacum agg.) seeds dried in mowed inflorescences

2010 ◽  
Vol 56 (No. 12) ◽  
pp. 580-583 ◽  
Author(s):  
Z. Martinková ◽  
A. Honěk
Keyword(s):  
Seed Dispersal ◽  
High Temperatures ◽  
Seed Viability ◽  
Late Summer ◽  
Seed Maturation ◽  
Ripe Seed ◽  
Viable Seeds

After flowering has ceased, dandelion (Taraxacum agg.) capitula close to enable maturation of seeds. In late summer the period of seed maturation lasts for 9 days. The capitula mowed later than 4 days after the start of this period and desiccated at 25°C produce viable seeds. If cut and prostrated on insolated ground inflorescences can experience temperatures exceeding 50°C which may impair seed viability. We determined the effect of desiccation temperature (5, 15, 25, 35, 45 or 55°C) on viability of ripening seeds using inflorescences harvested on September 5, 2008 at Prague-Ruzyne (50°05'N, 14°18'09 E), five days after flowering ceased (about 4 days before seed dispersal). As control, ripe seeds were collected at dispersal on the same day and desiccated at identical temperatures. Desiccated seeds were germinated at constant 17°C. Ripening seeds of maturing capitula only remained germinable if desiccation temperatures were ≤ 35°C (optimum 25°C) and were killed at 45 and 55°C. The viability of ripe seed was not affected by any of the desiccation temperatures. Time of germination of 50% seeds that germinated was significantly shorter in ripe than ripening seeds. Exposure of mowed dandelion inflorescences on insolated ground (solarization) may thus decrease production of viable seeds because of high temperatures experienced during desiccation.  

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