RT journal article
T1 Seed Size, Not Dispersal Syndrome, Determines Potential for Spread of Ricefield Weeds by Gulls
A1 Peralta-Sánchez, Juan Manuel
A1 Ansotegui, Albán
A1 Hortas Rodríguez-Pascual, Francisco
A1 Redón, Stella
A1 Martín-Vélez, Víctor
A1 Green, Andy J.
A1 Navarro-Ramos, María J.
A1 Lovas-Kiss, Adam
A1 Sánchez Ordoñez, Marta Isabel
A2 Biología
K1 endozoochory
K1 lesser black-backed gull
K1 Larus fuscus
K1 dry-fruited seeds
K1 fleshy-fruited seeds
K1 dispersal syndromes
AB Recent field data suggest that migratory gulls disperse many rice field weeds by gutpassage (endozoochory), most of which are dry fruited and widely assumed to have no long-distancedispersal mechanisms, except via human activity. We investigated this mechanism with a feedingexperiment, in which seeds of five common rice field weeds (in order of increasing seed size: Juncusbufonius, Cyperus difformis, Polypogon monspeliensis, Amaranthus retroflexus, and the fleshy-fruitedSolanum nigrum) were fed to seven individuals of lesser black-backed gulls Larus fuscus held incaptivity. We quantified seed survival after collecting faeces at intervals for 33 h after ingestion, thenextracting intact seeds and running germination tests, which were also conducted for control seeds.All five species showed high seed survival after gut passage, of >70%. Gut retention times averaged2–4 h, but maxima exceeded 23 h for all species. Germinability after gut passage was 16–54%, andgut passage accelerated germination in J. bufonius and S. nigrum, but slowed it down in the otherspecies. All species had lower germinability after gut passage compared to control seeds (likelydue to stratification prior to the experiment), but the loss of germinability was higher in smallerseeds. There was no evidence that the different dispersal syndromes assigned to the five species(endozoochory, epizoochory or barochory) had any influence on our results. In contrast, mean gutretention time was strongly and positively related to seed size, likely because small seeds pass morequickly from the gizzard into the intestines. Non-classical endozoochory of dry-fruited seeds bywaterbirds is a major but overlooked mechanism for potential long-distance dispersal, and moreresearch into this process is likely essential for effective weed management.
PB MDPI
SN 2223-7747
YR 2023
FD 2023
LK http://hdl.handle.net/10498/32446
UL http://hdl.handle.net/10498/32446
LA eng
DS Repositorio Institucional de la Universidad de Cádiz
RD 11-nov-2026