Dispersal models alert on the risk of non‐native species introduction by Ballast water in protected areas from the Western Antarctic Peninsula

Abstract

Aim:The Western Antarctic Peninsula is challenged by climate change and increasing maritime traffic that together facilitate the introduction of marine non-native species from warmer regions neighbouring the Southern Ocean. Ballast water exchange has been frequently reported as an introduction vector. This study uses a Lagrangian approach to model the passive drift of virtual propagules departing from Ballast water hypothetic exchange zones, at contrasting distances from the coasts.Location: Western Antarctic Peninsula. Methods: Virtual propagules were released over the 2008-2016 period and at three distances from the nearest coasts: 200 (convention for the management of Ballast Water, 2004), 50 or 11 nautical miles (NM). Results: Results show that exchanging Ballast water at 200 NM considerably reduces the arrival of propagules in proposed marine protected areas of the western side of the Antarctic Peninsula. On the eastern side, propagules can reach north-eastern marine protected areas within a few days due to strong currents for all tested scenarios. Seasonal and yearly variations indicate that exceptional climate events could influence the trajectory of particles in the region. Ballast water should be exchanged at least 200 NM offshore on the western side of the Antarctic Peninsula and avoided on the eastern side to limit particle arrival in proposed marine protected areas. Focusing on Deception Island, our results suggested that the Patagonian crab (Halicarcinus planatus) observed in 2010 could have been introduced in case of Ballast water exchange at 50 NM or less from the coast.Main conclusions: This study highlights the importance of respecting Ballast water exchange convention to limit the risk of non-native species introduction. Ballast water exchange should be operated at least at 200 NM from the coasts, which further limits particle arrival in shallow water areas. This is especially important in the context of a more visited and warmer Southern Ocean.Valérie Dulière and Charlène Guillaumot share co first-authorship.

Long‐term studies on West Antarctic Peninsula phytoplankton blooms suggest range shifts between temperate and polar species

“…Its presence can be attributed either to shipping‐mediated introduction or to range expansion. The rapid warming of the WAP and the increase in human activities increase the vulnerability of this geographic region to the introduction of non‐native species (Dulière et al., 2022; Hughes et al., 2020). Recent reports indicate the existence of five non‐native marine species in Antarctica (McCarthy et al., 2019), with nine additional species identified as high‐risk for invading the Antarctic Peninsula (Hughes et al., 2020).…”

“…These mostly include marine invertebrates, but none of them is a microalga. The South Shetland Islands are among the areas most impacted by ship traffic in Antarctica (McCarthy et al., 2022), which heightens the risk of the introduction of non‐native marine species such as the Patagonian crab (Dulière et al., 2022).…”

Ballast Water Utopia and Some Environmental Protection Ideas

“…While dynamics of Antarctica are different from those of the Arctic in that the Antarctic is not a populous area with attractive shipping lanes for trade. However, due to untreated ballast water being introduced in the area, researchers also warn of the dangers of foreign waters being introduced together with AIS into the Antarctic Treaty region [34]. Authors, Dulière et al in a scientific experiment running along a 9-year period conducted along the location of the Western Antarctic Peninsula, evidence of the introduction of AIS from ballast water can be overcome by encouraging ships to exchange foreign ballast water at least 200 nautical miles from the Antarctic region.…”

Identifying marine invasion threats and management priorities through introduction pathway analysis in a remote sub‐Antarctic ecosystem

“…Non‐native species dispersal through ballast water (Dulière et al., 2022 ; Lewis et al., 2003 ; McCarthy et al., 2019 ) is globally regulated (though not strictly implemented) through the IMO Ballast Water Management Convention (IMO, 2004 ), and recommendations specifically for the polar regions are outlined in the Antarctic Ballast Water Guidelines (IMO, 2007 ). These guidelines require exchange or release of ballast waters offshore (north of either the Polar Frontal Zone or 60° S, and at least 200 nautical miles from the nearest land).…”