Influence of environmental factors and sessile biota on vagile epibionts: The case of amphipods in marinas across a regional scale

Abstract

Marinas are highly anthropized environments, with singular ecological characteristics. In the present study the spatial variability of the amphipod assemblage associated to floating pontoons was analyzed. Moreover, the influence of the environmental data and the sessile biota on the amphipod assemblage structure were assessed. Six marinas were selected along the Southern Iberian Peninsula, three in the Atlantic and three in the Mediterranean, and three floating pontoons were sampled at each marina. Four-teen amphipod species were identified, most of them corresponded to detritivores and generalist species. Statistical analyses considering amphipod composition and abundance did not show significant differences between the Atlantic and the Mediterranean, but there were significant differences among marinas. Copper had a significant correlation with the amphipod assemblage. The sessile species Bugula neritina and Ellisolandia elongata also showed a significant influence on the spatial patterns of the amphipod assemblages. Therefore, environmental conditions and sessile composition seem to affect, simultaneously, the spatial variability of amphipod assemblage associated to floating pontoons in marinas. Both factors are key to understand the singularity of marinas. This fact should be taken into consideration to prevent the use of a single management program in these environments.

Quick spreading of the exotic amphipod Laticorophium baconi (Shoemaker, 1934): another small stowaway overlooked?

“…The greater the abundance of the species, the greater its probability of colonising anthropogenic vectors and expanding to new locations (Floerl et al, 2005;Ros et al, 2020;Revanales et al, 2023). Since L. baconi reaches high densities on pontoons (Saenz-Arias et al, 2022a;present study), it is to be expected that it can easily colonise the hulls of adjacent moored boats and spread by recreational boating (Martínez-Laiz et al, 2019). In fact, L. baconi was found in hull fouling during the present study.…”

“…As this juvenile was collected from a fish net placed in the water for a year, the specimen probably arrived dragged by the currents from the Koumac marina, where the species is established. Thus, throughout its introduced range, L. baconi is more abundant in artificial habitats, mainly occurring as a fouling organism in commercial ports and marinas, where it can be one of the dom-inant peracarid species (Saenz-Arias et al, 2022a). Based on this, we suggest recreational boating and commercial shipping, mainly through hull fouling and secondarily ballast waters, as the likely vectors for introduction and secondary spread of L. baconi.…”

Amphipods in Mediterranean Marine and Anchialine Caves: New Data and Overview of Existing Knowledge

“…This is the case of Apocorphium acutum, Apolochus spp., Coxischyrocerus inexpectatus, Ericthonius spp. and the exotic species Jassa slatteryi [104,105]. On the other hand, other recorded amphipod species have been associated with unpolluted environments, such as Harpinia pectinata, Microjassa cumbrensis and Stenothoe dollfusi [106,107].…”