Surveys of Undaria pinnatifida (Laminariales, Phaeophyta) in Golfo Nuevo, Argentina

Abstract

In December 1992, some sporophytes of the Asian kelp Undaria pinnatifida were found growing subtidally at 6 m depth below `A . Storni' Port, Puerto Madryn, Argentina . During the winter of 1994, the species expanded significantly from its original location . Sporelings appear in early autumn and attain their maximum size (1 .65 ± 0 .10 m) during winter and early spring, when most of them become fertile . The fronds are lost in summer, with only some holdfasts and sporophylls surviving, and these disappear by the end of summer . The occurrence of U. pinnatifida in Golfo Nuevo is reportedly due to an accidental introduction by cargo ships or fishing vessels arriving from Asian ports .

Introduced brown algae in the North East Atlantic, with particular respect toUndaria pinnatifida (Harvey) suringar

“…The other brown algae were also only found more downstream at the Port Hamble and Hamble Point Marinas and were absent from the more freshwater influenced Mercury and Swanwick Marinas. Clearly, Undaria is tolerant of a much wider range of environmental conditions than these algae and this ability to colonise sheltered substrata not covered by native species was also noted by Casas and Piriz (1996) in their study of an introduced Undaria population in Argentina. Outside the Hamble, only the outer positioned, more wave-washed floats of marinas supported reasonably well developed communities of large brown algae.…”

“…Even Styela clava, a very common host when occurring on floating structures, is very rarely found with attached Undaria when growing on fixed structures. This does seem surprising in view of numerous world wide reports highlighting Undaria's frequent tendency to colonise fixed artificial structures (Hay, 1990;Brown & Lamare, 1994;Casas & Piriz, 1996;Floc'h et al, 1996). Apart from scattered isolated plants found on the pilings, the only other non-floating population of Undaria observed in the Hamble comprises a number of small plants first seen on 1 June 1996 at LWST on a shingle spit at the Hamble entrance, a short distance from the Hamble Point Marina.…”

Differential shuffling of native genetic diversity across introduced regions in a brown alga: Aquaculture vs. maritime traffic effects

“…Furthermore, although close geographically and connected via shipping traffic, Tasma 29) was highly similar to Melbourne, suggesting a single common origin for both introductions. Tasmania, on the other hand, appears to have arisen from an isolated and independent primary introduction.…”

The structure of biogenic habitat and epibiotic assemblages associated with the global invasive kelp Undaria pinnatifida in comparison to native macroalgae

“…Undaria pinnatifida (Harvey) Suringar 1873 (also known as Wakame or Japanese Kelp), which originates in the temperate northwest Pacific, is widely regarded as one of the most invasive marine species on Earth (listed in the '100 of the World's Worst Invasive Alien Species', Invasive Species Specialist Group, IUCN 2013), having established populations in the northeast Atlantic (Castric-Fey et al, 1993;Fletcher and Manfredi, 1995), northern Mediterranean (Cecere et al, 2000), southwest Atlantic (Casas and Piriz, 1996), southern Pacific (Hay and Luckens, 1987) and the eastern Pacific (Silva et al, 2002). U. pinnatifida was first recorded in UK waters in the Hamble estuary in 1994 (Fletcher and Manfredi, 1995) and has since spread along the south coast of England (Heiser et al, 2014).…”