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Strong potential for endozoochory by waterfowl in a rare, ephemeral wetland plant species, Astragalus contortuplicatus (Fabaceae)

100%

Lovas-Kiss A., Sonkoly J., Vincze O., Green A. J., Takacs A., Molnar A. V.

Acta Societatis Botanicorum Poloniae

2015

tom 84

nr 3

It was proposed previously that passive dispersal by migratory aquatic birds explain the widespread distribution of many wetland organisms. Several experimental studies have shown that many widespread wetland plant species can be readily dispersed within the guts of Anatidae. However, it is unclear whether plants with a more restricted distribution are able to disperse via waterbirds. This paper addresses the dispersal ability and germination ecology of the little-known Hungarian milkvetch Astragalus contortuplicatus, which occurs on banks of continental rivers and has a limited and unpredictable distribution. To test whether limited capacity for endozoochory by waterfowl could explain the sporadic appearance of this species, we force-fed ten captive mallards (Anas platyrhynchos) with 100 milkvetch seeds each. Droppings were collected for up to 45 h after feeding. Intact and viable seeds were found in the droppings of each mallard, and altogether 24.7% of seeds fed were recovered intact. The proportion of retrieved seeds that germinated (27.0%) was significantly higher than that of untreated control seeds (0.5%), but significantly lower than that of mechanically scarified seeds (96.0%). Retrieved seeds that germinated developed into healthy mature plants. Given the average flight velocity of mallards, seeds of A. contortuplicatus may travel up to 1600 km inside the digestive tract of migrating individuals. Our results suggest that avian vectors may be more important for the dispersal of rare higher plants (especially those with a hard seed-coat) than hitherto considered. Moreover, they suggest that rarity does not necessarily indicate limited dispersal ability, and may instead be explained by specific habitat requirements.

Cestodes from Artemia parthenogenetica [Crustacea, Branchiopoda] in the Odiel Marshes, Spain: A systematic survey of cysticercoids

100%

Georgiev B. B., Sanchez M. I., Green A. J., Nikolov P. N., Vasileva G. P., Mavrodieva R. S.

Acta Parasitologica

2005

tom 50

nr 2

A total of 3,300 specimens of brine shrimps Artemia parthenogenetica from the Odiel Marshes, Huelva Province, SW Spain, were studied during several seasons of 2002 and 2003 for the presence of cestode infections. Cysticercoids were found in 26.8% of brine shrimps. Eight cestode species were recorded, i.e., Hymenolepididae: Flamingolepis liguloides (adults parasitic in flamingos) with prevalence (P) 18.5%, mean intensity (MI) 1.48 and mean abundance (MA) 0.28; F. flamingo (adults parasitic in flamingos), P 0.9%, MI 1.03, MA 0.01; Confluaria podicipina (adults parasitic in grebes), P 6.5%, MI 1.42, MA 0.09; Wardium stellorae (adults parasitic in gulls), P 0.2%, MI 1.00, MA 0.002; Dilepididae: Eurycestus avoceti (adults parasitic in waders and flamingos), P 2.7%, MI 1.08, MA 0.03; Anomotaenia sp., probably A microphallos (adults parasitic in waders), P 0.8%, MI 1.04, MA 0.01; A tringae (adults parasitic in waders), P 2.2%, MI 1.01, MA 0.02; Progynotaeniidae: Gynandrotaenia stammen (adults parasitic in flamingos), P 0.6%, MI 1.00, MA 0.01. The cysticercoids are described and accompanying illustrations are presented. This study provides the first record of Anomotaenia tringae in an intermediate host and the first records of C. podicipina, E. avoceti, A. tringae and G. stammeri in Spain.

Larval helminths in the invasive American brine shrimp Artemia franciscana throughout its annual cycle

84%

Georgiev B. B., Angelov A., Vasileva G. P., Sanchez M. I., Hortas F., Mutafchiev Y., Pankov P., Green A. J.

Acta Parasitologica

2014

tom 59

nr 3

One of the best examples of rapid displacement of native species by an invader is the eradication of native Artemia salina and A. parthenogenetica in the Mediterranean by the introduced American A. franciscana. Previous studies based on sampling from limited time periods suggest that the success of the American species as a competitor may be due partly to different parasite burden, since native Artemia spp. have high cestode infection rates regulating their density. The aim of this study is to test the hypothesis that the helminth infection in A. franciscana in its invasive range is low throughout its annual life cycle. Samples of A. franciscana were collected every second month from La Tapa saltern (Andalusia) during one year. Five helminth species were recorded: cestodes Flamingolepis liguloides, F. flamingo, Gynandrotaenia stammeri (all flamingo parasites), Eurycestus avoceti (a shorebird parasite) and larval spirurids of the Acuariinae (the first record of nematodes in Artemia). The overall infection rate was low, with total prevalence 5.9% and prevalence of individual parasite species between 0.2 and 3.2%. The mean abundance of helminths was 0.005–0.155 (av. 0.068), 5–13 times lower than in native congeners. Waterbird counts indicate that the low infection rates cannot be explained by lack of definitive hosts. The results are consistent with the hypothesis that helminths have no regulating effect on the invasive brine shrimp in the Mediterranean. The replacement of the native populations by the invader can be partially explained by a competition mediated by parasites/predators through a differential impact on host fitness.

Ograniczanie wyników

2 Acta Parasitologica

1 Acta Societatis Botanicorum Poloniae

3 Green A. J.

2 Georgiev B. B.

2 Sanchez M. I.

2 Vasileva G. P.

1 Angelov A.

1 Hortas F.

1 Lovas-Kiss A.

1 Mavrodieva R. S.

1 Molnar A. V.

1 Mutafchiev Y.

1 Nikolov P. N.

1 Pankov P.

1 Sonkoly J.

1 Takacs A.

1 Vincze O.

1 2015

1 2014

1 2005

Wyniki wyszukiwania

Strong potential for endozoochory by waterfowl in a rare, ephemeral wetland plant species, Astragalus contortuplicatus (Fabaceae)

Cestodes from Artemia parthenogenetica [Crustacea, Branchiopoda] in the Odiel Marshes, Spain: A systematic survey of cysticercoids

Larval helminths in the invasive American brine shrimp Artemia franciscana throughout its annual cycle