A kis lilik (Anser erythropus L.) és közel rokon nagytestű lúdfajok magterjesztésben betöltött szerepe és élőhelyi preferenciája a Hortobágyi Nemzeti Parkban

Abstract

-Several studies found that waterfowl are important endozoochorous dispersal vectors for plant species. Germination of the seed content of their droppings provides valuable information on their diet and also on their role in seed dispersal. Our aim was to analyse the seed dispersal potential of the critically endangered habitat-specialist Lesser White-fronted Goose (Anser erythropus) in their autumn and spring staging areas in Hortobágy National Park. The study was supported by the LIFE10-NAT/GR/000638 project. We also studied the seed dispersal potential of larger generalist goose species foraging in the same areas, such as Greater White-Fronted Goose (Anser albifrons Scopoli) and Greylag Goose (Anser anser L.). We asked the following questions: (i) Which habitat types are the most frequently used by Lesser White-fronted Goose and larger goose species? (ii) Is the different habitat preference of Lesser White-fronted Goose and larger goose species reflected in the seed content of their droppings? (iii) Are there seasonal differences between the seed content of spring and autumn droppings? We identified the most frequently used feeding habitats. We collected 40 droppings of Lesser White-fronted Goose and larger goose species per site in April and October 2012, in total we collected 720 droppings per species. Droppings were concentrated and spread on trays filled with sterilised potting soil. Samples were germinated in a greenhouse from April to November 2013. In total we germinated 21 plant species from the goose droppings, which suggests that goose species play an important role in seed dispersal. We found that Lesser White-fronted Goose dispersed more species typical to alkali habitats, and fewer weeds compared to larger goose species. Lesser White-fronted Goose and larger goose species used a wide range of feeding habitats, thus, they play an important role in dispersing seeds between habitats along a moisture gradient. Total species number and species number of plant functional groups were higher in autumn droppings. Seed content of the droppings suggests that Lesser White-fronted Goose is confined to natural habitats, thus for the effective protection of this critically endangered species it is crucial to preserve its natural feeding habitats.Keywords: alkali landscape, animal-mediated plant dispersal, Anser erythropus, germination, vulnerable species, wetland Összefoglaló -Az állatok általi magterjesztésnek igen jelentős szerepe van a növényi elterjedési mintázatok kialakításában. Újabb kutatások kimutatták, hogy a vízimadarak is igen jelentős szerepet tölthetnek be a növényi magterjesztésben. A zoochor magterjesztés vizsgálatával egyrészt megérthetjük az állati terjesztő vektorok szerepét a növényi terjedésben, másrészt fontos