Dispersal of aquatic invertebrates by lesser black-backed gulls and white storks within and between inland habitats

• Published in: Aquatic Sciences
• Main Authors: Martín-Vélez, Víctor, Sánchez, Marta I., Lovas-Kiss, Ádám, Hortas, Francisco, Green, Andy J.
• Other Authors: Conferencia de Rectores de las Universidades Españolas, Consejo Superior de Investigaciones Científicas (España), Fundación "la Caixa", Ministerio de Economía, Industria y Competitividad (España), Agencia Estatal de Investigación (España), European Commission, Hungarian Academy of Sciences, Ministry of Innovation and Technology (Hungary)
• Format: Article in Journal/Newspaper
• Language: English
• Published: Springer Nature 2022
• Subjects: Waterbirds; Artemia; Cladocera; Endozoochory; Gastropoda; Lesser black-backed gull
• Online Access: http://hdl.handle.net/10261/273469; https://doi.org/10.1007/s00027-021-00842-3; https://doi.org/10.13039/501100010198; https://doi.org/10.13039/501100003339; https://doi.org/10.13039/501100000780; https://doi.org/10.13039/501100011033; https://api.elsevier.com/content/abstract/scopus_id/85121348201

Waterbirds can transport aquatic invertebrates internally, contributing to metapopulation dynamics between aquatic habitats in a terrestrial matrix. However, research into this dispersal process to date has focused on individual field sites or laboratory studies. We investigated the invertebrates dispersed by endozoochory by the lesser black-backed gull Larus fuscus wintering in Andalusia, south-west Spain in 2016–2017, comparing seven sites interconnected by their movements, with different degrees of anthropogenization [three landfills, two saltpan complexes, a natural lake, and a large (370 km2) ricefield area]. In the ricefields, we also compared invertebrates dispersed by gulls with those dispersed by the larger white stork Ciconia ciconia. A total of 642 intact invertebrates and their propagules (mainly plumatellid bryozoans, cladocerans, and other branchiopods) were recorded in excreta (faeces and pellets) from gulls and storks. A greater diversity and abundance of invertebrates were recorded in ricefields, notably 43 individuals of the alien snail Physella acuta. One snail was still alive in a gull pellet 3 weeks after being stored in a fridge. This represents the first record of snail dispersal within waterbird pellets. Viability was also confirmed for the cladoceran Macrothrix rosea recorded in ricefields, and the alien brine shrimp Artemia franciscana recorded mainly in saltpans. In ricefields, gulls and pellets had significantly fewer propagules and fewer taxa per gram of excreta than storks and faeces, respectively. Through their high mobility, gulls and storks can disperse invertebrates between different natural and artificial habitats, and even to landfills. They can promote metapopulation dynamics for native bryozoans and branchiopods, but also the spread of invasive snails and brine shrimp. Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature. “La Caixa-Severo Ochoa 2016” (VMV). Ministerio de Economía, Industria y Competitividad project CGL2016-76067-P (AEI/FEDER, ...