scholarly journals Complementary endozoochorous seed dispersal by large mammals in the Golestan National Park, Iran

2018 ◽  
Vol 28 (4) ◽  
pp. 294-302 ◽  
Author(s):  
Sorour Karimi ◽  
Mahmoud-Reza Hemami ◽  
Mostafa Tarkesh Esfahani ◽  
Hossein Akhani ◽  
Christophe Baltzinger

AbstractLarge animals tend to disperse seeds over long distances via ingestion and defecation due to their large home range and capacity to move among different habitats for feeding. The aim of this study was to investigate the potential of endozoochorous seed dispersal by five herbivores: Ovis vignei, Capra aegagrus, Gazella subgutturosa, Cervus elaphus, Capreolus capreolus and two omnivores: Sus Scrofa and Ursus arctos in the Golestan National Park, northeast of Iran, by a greenhouse germination experiment. A total of 3107 seedlings belonging to 154 different plant taxa were germinated from 655 dung samples collected in three different habitats. Plant families that most frequently germinated were Poaceae and Brassicaceae. Urtica dioica was the most abundant germinating seed, accounting for 20% of all the seedlings recorded in our dung samples, whereas the most frequently observed species was Portulaca oleracea, which occurred in 24% of our samples. We showed that 54% of the seeds germinating were dispersed by only one of the mammals studied. Herbs and graminoids were the most frequently dispersed growth forms by the herbivores and the wild boar, whereas brown bears mostly dispersed shrubs. The seedling composition in the dung samples was strongly correlated with the local flora especially for non-selective feeders, like red deer. The differences observed in the number of plants and frequency of different growth forms dispersed among the studied mammals reflect their body size, digestive physiology, and dietary and habitat preferences. Our findings highlight the different and complementary roles of large herbivores and omnivores as long-distance seed dispersal vectors.

2018 ◽  
Vol 7 (2) ◽  
pp. 29-42
Author(s):  
S. karimi ◽  
M.R. Hemami ◽  
M. Tarkesh Esfahani ◽  
Ch. Baltzinger ◽  
◽  
...  

2005 ◽  
Vol 21 (3) ◽  
pp. 263-271 ◽  
Author(s):  
Alan E. Burger

The distribution of the forest tree Pisonia grandis (Nyctaginaceae) coincides with seabird colonies on small tropical islands. Its seeds are enclosed in a calyx exuding extremely sticky resin which adheres strongly to feathers. Birds are obviously seed-dispersal vectors, but the multi-seeded infructescences frequently entangle birds, often fatally. On Cousin Island, Seychelles, I investigated the production, germination, survival, and tolerance to seawater of Pisonia seeds, and the occurrence of entanglement with birds. Fresh seeds had high germination success (62–87% in experimental trays), but seedling survival in Cousin's forests was low (0.1% of 6020 seeds survived as seedlings after 2–8 mo). Some seeds tolerated 30 min daily immersions in seawater (8–15% germination after 14–28 d treatment), but not continuous immersion in seawater (reduced germination after 5 d and none after 12 d). Inter-island dispersal is likely via living unencumbered seabirds carrying a few seeds, but not on floating carcasses. Seeds attached to carcasses did not have improved germination or survival. Intra-island propagation is almost entirely vegetative, with negligible local seed dispersal. Pisonia plants therefore do not benefit from fatal entanglements. The extreme stickiness of the seeds evidently evolved to resist removal by seabirds and so facilitate long-distance dispersal. The mortality of some potential vectors is an unfortunate consequence, but has little impact on the large populations of tree- and ground-nesting seabirds which nest in or under these trees.


2020 ◽  
Author(s):  
Sorour Karimi ◽  
Mahmoud-Reza Hemami ◽  
Mostafa Tarkesh Esfahani ◽  
Christophe Baltzinger

Abstract Background: Vertebrate-mediated seed dispersal is probably the main long distance dispersal mode. Through endozoochory, large mammals act as mobile links between habitats within and among forest patches. Along with other factors, their feeding regimes do affect their contribution as dispersal vectors. We conducted a cross-species comparative experiment involving two herbivores, red deer and roe deer; and two opportunistic omnivores, wild boar and brown bear, all occurring in the forest and steppe-forest ecotone habitats of the south-eastern Caspian region. We compared their role as endozoochorous seed dispersal agents by monitoring seedling emergence in their dungs under greenhouse and natural conditions. Results: In total, 3078 seedlings, corresponding to 136 plant taxa sprouted from 445 paired dung sub-samples, under greenhouse and natural conditions. Only 336 seedlings, corresponding to 36 plant taxa, emerged under natural conditions, among which five taxa did not appear under greenhouse conditions. Graminoids and forbs composed 91% of the seedlings in the greenhouse whereas shrubs were more abundant under natural conditions, representing 55% of the emerged seedlings. Under greenhouse conditions, first red deer and then wild boar dispersed more species than the other two mammals, while under natural conditions brown bear was the most effective vector. We observed remarkably higher species richness and seedling abundance per dung sub-sample under buffered greenhouse conditions than we did under natural conditions. Conclusions: The four sympatric mammals studied provided different seed dispersal services, both in terms of seedling abundance and species richness and may therefore be regarded as complementary. Our results highlight a positive bias when only considering germination under buffered greenhouse conditions. This must be taken into account when planning management options to benefit plant biodiversity based on the dispersal services concluded from greenhouse experiments.


2014 ◽  
Author(s):  
Ελένη Σαμαρτζίδου

Σκοπός της παρούσας εργασίας είναι η ανάλυση του ζωοαρχαιολογικού υλικού του λιμναίου νεολιθικού οικισμού του Δισπηλιού. Συγκεκριμένες κατηγορίες οστών καταγράφηκαν, χρησιμοποιήθηκαν οι μέθοδοι ποσοτικοποίησης NISP, MinAU και MNI για την ποσοτικοποίηση του υλικού, ο ταξινομικός προσδιορισμός έγινε με άτλαντες και εργαστηριακές συλλογές. Όσον αφορά την ταφονομική ιστορία των οστών, ελέγχθηκε η αντιπροσωπευτικότητα του δείγματος βάσει του τρόπoυ ανάκτησής του, καταγράφηκε η επικάλυψή τους με ιζήματα, τα σημάδια βρώσης από άλλα ζώα, η κατάσταση διατήρησης τους, το χρώμα τους, τα αποτυπώματα ριζών, η καύση και η θραύση τους. Όσον αφορά στην εκμετάλλευση των κουφαριών των ζώων από τον άνθρωπο, παρουσιάστηκε η ανατομική τους αντιπροσώπευση, η οποία συσχετίστηκε με τη διατροφική χρησιμότητα των μερών των κουφαριών, υπολογίστηκε η ποσότητα κρέατος που καταναλώθηκε με βάση το δείγμα, καταγράφηκαν τα σημάδια σφαγής, εκδοράς, διαμελισμού και τεμαχισμού των οστών, διερευνήθηκε η εκμετάλλευση του μυελού και λίπους των οστών βάσει της μορφολογίας θραύσης τους. Τέλος, τα οστέινα εργαλεία παρουσιάζονται εν συντομία και συσχετίζονται με το υπόλοιπο οστεολογικό υλικό. Η διαχείριση των ζώων διερευνήθηκε ως εξής: αρχικά, διαχωρίστηκαν βάσει των μετρήσεων τα ήμερα, άγρια και πιθανώς ημι-άγρια άτομα συγκεκριμένων ειδών, διακρίθηκε το αρσενικό και θηλυκό φύλο με μορφολογικά κριτήρια και με μετρήσεις, υπολογίστηκε η ηλικία θανάτωσης των ειδών βάσει των γνάθων και του μετακρανιακού υλικού των ζώων, καταγράφηκαν και ερμηνεύτηκαν τα παθολογικά χαρακτηριστικά των οστών. Επιπλέον, διερευνήθηκε η εποχικότητα εκμετάλλευσης των ζώων βάσει της ηλικίας θανάτωσής τους. Συγκεκριμένα, στην παρούσα εργασία καταγράφηκαν συνολικά 74.190 οστά, από τα οποία τα 27.512 (37%) προσδιορίστηκαν σε επίπεδο είδους ζώου ή μέρους του σκελετού. Η σημασία της ήμερης πανίδας είναι φανερή σε όλες τις φάσεις κατοίκησης, ενώ παρουσιάζεται μια σταδιακή αύξηση της άγριας πανίδας προς τις μεταγενέστερες φάσεις. Aνάμεσα στα ήμερα είδη το πρόβατο (Ovis aries) είναι το πιο συχνό είδος, ακολουθούμενο από το χοίρο (Sus domesticus), το βόδι (Bos taurus), την αίγα (Capra hircus) και το σκύλο (Canis familiaris). Η παρουσία των οστών ιπποειδών χρήζει περαιτέρω διερεύνησης. Ανάμεσα στα άγρια είδη, το κόκκινο ελάφι (Cervus elaphus) και το ζαρκάδι (Capreolus capreolus) υπερέχουν αριθμητικά, ενώ ο αγριόχοιρος (Sus scrofa) και ο λαγός (Lepus capensis) ακολουθούν. Τα λιγότερο συχνά είδη είναι τα εξής: το άγριο βόδι (Bos primigenius), η αλεπού (Vulpes vulpes), η καφέ αρκούδα (Ursus arctos), ο ασβός (Meles meles), η ενυδρίδα (Lutra lutra), το πετροκούναβο (Martes foina), ο σκίουρος (Sciurus vulgaris), ο σκαντζόχοιρος (Erinaceus europaeus). Καταγράφηκαν και οστά από πτηνά, από χελώνα, από τρωκτικά/εντομοφάγα και από τις οικογένειες Ranidae και Bufonidae. Τα ήμερα βόδια εκτρέφονταν για το κρέας και το γάλα τους, ενώ δεν υπάρχει καμία παθολογική ένδειξη που να δείχνει ότι χρησιμοποιούνταν συστηματικά σε σκληρές εργασίες. Οι χοίροι θανατώνονταν για το κρέας και το λίπος τους. Τα αιγοπρόβατα τα εκμεταλλεύονταν για το κρέας, το γάλα και το μαλλί/τρίχα με μια έμφαση στην παραγωγή κρέατος. Η ηλικία θανάτωσης των ελαφοειδών δείχνει μια στόχευση σε νεαρά ενήλικα άτομα. Η επιλογή των μερών των σφαγίων φαίνεται ότι αποσκοπούσε στην εξασφάλιση της μεγαλύτερης δυνατής ποσότητας κρέατος. Η θραύση των οστών για την εξαγωγή μυελού ήταν πιο εντατική στα βόδια παρά στα αιγοπρόβατα και στους χοίρους, ενώ υπήρχε μια προτίμηση για την εξαγωγή μυελού από ώριμα άτομα. Το υλικό του Δισπηλιού δε διαφοροποιείται από τα υπόλοιπα ζωοαρχαιολογικά υλικά της ίδιας εποχής του ελλαδικού χώρου, ενώ αντιθέτως παρουσιάζει σημαντικές διαφορές σε σχέση με τα υλικά των Βαλκανίων και των λιμναίων οικισμών της Κεντρικής Ευρώπης.


2018 ◽  
Vol 79 (2) ◽  
pp. 119-124
Author(s):  
Robert W. Mysłajek ◽  
Sabina Nowak ◽  
Maciej Romański ◽  
Katarzyna Tołkacz

Abstract The diet of wolves Canis lupus L. was assessed in the Wigry National Park in North-Eastern Poland, which overlaps with the Natura 2000 site “Ostoja Wigierska”. The content of a total of 149 scat samples was collected in 2017 and analysed in order to determine dietary composition. Wolves primarily feed on wild ungulates, which make up 75.4% of food biomass. Despite the fact that wild boar Sus scrofa L. and red deer Cervus elaphus L. dominate in the ungulate community in the study area, the primary prey species was observed to be roe deer Capreolus capreolus L. with 39.6%, while red deer and wild boar only constituted 18.7% and 8.3% of the food biomass, respectively. Additionally, beaver Castor fiber L. was found to be an important prey (10.9%) as well and livestock accounted for 15.1% of all biomass consumed. The livestock eaten by wolves also included carcasses of domestic animals illegally disposed of in the forest. We therefore conclude that decisions on the management of the wolf’s food base within protected areas, such as national parks or Natura 2000 sites, should be preceded by intensive local studies.


2020 ◽  
Vol 8 (1) ◽  
Author(s):  
Stephen J. Wright ◽  
Marco Heurich ◽  
Carsten M. Buchmann ◽  
Reinhard Böcker ◽  
Frank M. Schurr

Abstract Background Long-distance seed dispersal (LDD) has strong impacts on the spatiotemporal dynamics of plants. Large animals are important LDD vectors because they regularly transport seeds of many plant species over long distances. While there is now ample evidence that behaviour varies considerably between individual animals, it is not clear to what extent inter-individual variation in behaviour alters seed dispersal by animals. Methods We study how inter-individual variation in the movement and feeding behaviour of one of Europe’s largest herbivores (the red deer, Cervus elaphus) affects internal seed dispersal (endozoochory) of multiple plant species. We combine movement data of 21 individual deer with measurements of seed loads in the dung of the same individuals and with data on gut passage time. These data serve to parameterize a model of passive dispersal that predicts LDD in three orientations (horizontal as well as upward and downward in elevation). With this model we investigate to what extent per-seed probabilities of LDD and seed load vary between individuals and throughout the vegetation period (May–December). Subsequently, we test whether per-seed LDD probability and seed load are positively (or negatively) correlated so that more mobile animals disperse more (or less) seeds. Finally, we examine whether non-random associations between per-seed LDD probability and seed load affect the LDD of individual plant species. Results The studied deer dispersed viable seeds of at least 62 plant species. Deer individuals varied significantly in per-seed LDD probability and seed loads. However, more mobile animals did not disperse more or less seeds than less mobile ones. Plant species also did not differ significantly in the relationship between per-seed LDD probability and seed load. Yet plant species differed in how their seed load was distributed across deer individuals and in time, and this caused their LDD potential to differ more than twofold. For several plant species, we detected non-random associations between per-seed LDD probability and seed load that generally increased LDD potential. Conclusions Inter-individual variation in movement and feeding behaviour means that certain deer are substantially more effective LDD vectors than others. This inter-individual variation reduces the reliability of LDD and increases the sensitivity of LDD to the decline of deer populations. Variation in the dispersal services of individual animals should thus be taken into account in models in order to improve LDD projections.


2005 ◽  
Vol 166 (3) ◽  
pp. 368 ◽  
Author(s):  
Katul ◽  
Porporato ◽  
Nathan ◽  
Siqueira ◽  
Soons ◽  
...  

2014 ◽  
Vol 172 (1-2) ◽  
pp. 272-278 ◽  
Author(s):  
Magdalena Rzewuska ◽  
Lucjan Witkowski ◽  
Agata A. Cisek ◽  
Ilona Stefańska ◽  
Dorota Chrobak ◽  
...  

2003 ◽  
Vol 81 (2) ◽  
pp. 266-271 ◽  
Author(s):  
Jerry O Wolff ◽  
Toni Van Horn

Animal behavior is often optimized as a trade-off between survival and reproduction. During the breeding season, mammals tend to maximize their reproductive effort within the constraints of predation pressure. When predation pressure is reduced, greater effort can be allocated to reproductive behavior and less to vigilance and predator avoidance. The objective of this study was to test the hypothesis that elk, Cervus elaphus, in Yellowstone National Park (YNP), with predators, would spend more time in vigilance and risk-avoidance behavior than would elk in Rocky Mountain National Park (RMNP), a predator-free environment. We further predicted that elk at Mammoth Hot Springs (MAM) in YNP would behave similarly to those at RMNP because predators were absent in that area of the park. Cow elk in YNP spent more time in vigilance and less in foraging during activity periods than did cows in RMNP or MAM. Also, elk in YNP retreated to forest cover during the midday inactive period, whereas elk in RMNP and MAM remained in open habitat. Vigilance was not correlated with group size at either site. Cows with calves spent more time in vigilance and less in foraging than did cows without calves in RMNP and YNP. Bull elk spent most of their time in courtship at all sites, but foraged more at RMNP than in YNP or MAM. Mean harem sizes were similar among the three sites: 17.0 in RMNP, 15.7 in YNP, and 19.0 in MAM. The proportion of cows with calves was significantly lower in the area with predators, YNP (0.10), than in the predator-free areas (0.24 in RMNP and 0.37 in MAM), probably because of greater calf mortality in YNP. Elk in YNP behaved in accordance with a predation risk, whereas those in RMNP and MAM showed less vigilance behavior.


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