Cnidarian Alien Species in Expansion

Abstract

The study of the diversity and composition of marine communities is the first step in understanding the development of marine ecosystems. While some cnidarian populations are in decline, others invade new regions and habitats. The pressure of the human actions on the marine ecosystems has increased in the past decades. The artificial structures in marine environments, shipping, aquaculture, global warming and interoceanic canals have contributed to the dispersion, establishment and invasion of many places by alien species around the world, in some cases, with major ecological and socio-economic impacts. Some cnidarian species may serve as examples of the truly widespread reach of invasive species. Benthic phase of hydroids and anthozoans are common components of harbours and fouling communities and, probably, they have been transported on ship hulls. Ephyrae and hydromedusae are also frequently found in ballast water. Additionally, the global climatic change allows cnidarian of tropical affinity to extend their range into the temperate zones. The biological invasions and range extensions may cause local native biodiversity and economic losses. Only recently have these biological invasions attracted the attention of the scientific community. Though invasive alien cnidarians are recognized now as a global threat to biodiversity, and monitoring their presence and impacts is considered a prerequisite for marine environmental management and sustainable development, it seldom takes place even in the coastal regions most vulnerable to introductions

Integration of physiological knowledge into hybrid species distribution modelling to improve forecast of distributional shifts of tropical corals

“…However, these regions were not projected as areas with declines in habitat suitability for coral reefs by other studies based on SDMs using the same scenarios (see Couce, Ridgwell, & Hendy, ), which did not incorporated physiological knowledge. The upper thermal limits found in our study agreed with those that define potential areas of bleaching for scleractinian corals (Donner, Skirving, Little, Oppenheimer, & Hoegh‐Gulberg, ), and with the future hyper‐tropical zone proposed by González‐Duarte, Megina, López‐González, and Galil, (), where mass mortalities are expected. The projected areas of decline determined by our Hybrid SDM represented 2.5% of the current suitable areas (~1.63 × 10 7 ha).…”

Hidden diversity under morphology–based identifications of widespread invasive species: the case of the ‘well–known’ hydromedusa Craspedacusta sowerbii Lankester 1880

“…Avoiding this problem by limiting OTUs data matrices to higher taxonomic levels or considering functional biodiversity (Cernansky, 2017) is not a viable solution, especially when working on NIS, whose influence at different levels on native ecosystems is well documented (e.g. Bax et al, 2003;Wallentinus and Nyberg, 2007;Walther et al, 2009;Poulin et al, 2011;González-Duarte et al, 2016;among others).…”

Widespread demographic explosion of a non-indigenous hydrozoan on an oceanic island

“…In the scientific literature, there is growing evidence of the number of invasive species, covering a broad range of taxonomic lineages and affecting almost all eco-regions of the world (Thomsen et al 2015). Within the phylum Cnidaria, only a small number of potential invasive hydroids (class Hydrozoa) have been described (González-Duarte et al 2016a). This is the case of Pennaria disticha Goldfuss, 1820 in Hawaii (Miglietta et al 2015), Turritopsis dohrnii (Weismann, 1883), considered as a global invader (Miglietta and Lessios 2009), Maeotias marginata (Modeer, 1791) in the Baltic Sea (Väinölä and Oulasvirta 2001), Moerisia lyonsi (Boulenger, 1908) in North America (Ma andPurcell 2005), andBlackfordia virginica Mayer, 1910.…”

“…This is the case of Pennaria disticha Goldfuss, 1820 in Hawaii (Miglietta et al 2015), Turritopsis dohrnii (Weismann, 1883), considered as a global invader (Miglietta and Lessios 2009), Maeotias marginata (Modeer, 1791) in the Baltic Sea (Väinölä and Oulasvirta 2001), Moerisia lyonsi (Boulenger, 1908) in North America (Ma andPurcell 2005), andBlackfordia virginica Mayer, 1910. The last species is found in estuarine zones of all oceans (Mills andSommer 1995, Haydar 2012), exerting a high predation pressure on planktonic crustaceans and fish eggs, with effects on commercial fish populations (González-Duarte et al 2016a). Similarly, Clytia hummelincki (Leloup, 1935) is invasive in the Mediterranean, preying on eggs and fish larvae (González-Duarte et al 2016b).…”

“…The colonies are very stinging and could be harmful to humans due to the presence of large nematocysts (100 μm in length, Marques et al 2002); indeed, this species has been given the common name "stinging hydroid". The increase in abundance of this species could reduce tourism activities and have a negative impact on local economies (Çinar et al 2006, González-Duarte et al 2016a.…”