A tropical fish community in thermal waters of southern Tuscany

Abstract

In a small stream of southern Tuscany (Fossa Calda), fed by hot springs, we discovered a fish community dominated by tropical species, some of which have never previously been reported in Euro-Mediterranean natural freshwater environments. The aim of our research was to ascertain whether the three most abundant and widespread species (Amatitlania nigrofasciata, Hemichromis sp. and Oreochromis niloticus) have become established. Analysis of size class distribution and growth curves showed that the populations of these species are quite large and made up of juveniles, subadults and adults, as is the case in self-sustaining populations. These fishes were probably released intentionally, since they are widely used in aquariums and aquaculture and their survival in Fossa Calda was possible because of the constant high temperature of thermal waters. Spread to other streams seems unlikely. In fact, at some distance from the hot springs, where water temperatures are lower, populations of the tropical species were small.

The First Tropical Alien Crayfish Species in European Waters: The Redclaw Cherax Quadricarinatus (Von Martens, 1868) (Decapoda, Parastacidae)

“…However, due to the warmer climate in Southern Europe, the increased numbers of aquaculture farms from which escapes are regularly reported (Ahyong & Yeo, 2007;Vázquez, 2008), and to its resistance to low winter temperatures (Karplus et al, 1998), the establishment of populations in the wild in Europe was expected, but with an estimated "medium" ranked invasion risk (Souty-Grosset et al, 2006;Tricarico et al, 2010). Other possibilities in Europe are specific habitats, for example thermal hot water springs, which can hold abundant and sustainable populations of tropical invaders, even in colder temperate climates (Šajna et al, 2007;Petutschnig et al, 2008;Piazzini et al, 2010).…”

Invasion of South American suckermouth armoured catfishes Pterygoplichthys spp. (Loricariidae) in Kerala, India - a case study

“…Native to the streams, floodplain lakes and marshes of South America, the suckermouth sailfin catfish Pterygoplichthys spp. have successfully invaded inland water bodies of various countries across the world, including Philippines (Joshi 2006;Hubilla et al 2007), Japan (Nakabo 2002), Taiwan (Wu et al 2011), Vietnam (Zworykin & Budaev 2013), Sri Lanka (Sumanasinghe & Amarasinghe 2013), Indonesia, Malaysia and Singapore (Page & Robins 2006), Israel (Golani & Snovsky 2013), Turkey (Ozdilek 2007), Bangladesh (Hossain et al 2008), Mexico (Armando et al 2007), Europe (Keszka et al 2008;Piazzini et al 2010;Simonovic et al 2010) and USA (Nico & Martin 2001).…”

First record of Amatitlania nigrofasciata (Günther, 1867) (Cichliformes: Cichlidae) as introduced species in natural freshwaters of Colombia

“…It is a tolerant and prolific species (Ishikawa and Katsunori 2010;TrujilloJiménez et al 2010), that once established might be difficult to eradicate (e.g., Hill and Cichra 2005;Hovey and Swift 2012). In other countries, it has been found reaching invasive category with strong established populations alongside native species (e.g., Piazzini et al 2010;Trujillo-Jiménez et al 2010;Mejía-Mojica et al 2015). The aggressive and territorial behaviour and omnivorous diet of this species could serve to compete with native species (Mendoza et al 2015).…”

“…As a result, it has been introduced into several countries including: The United States (Matlock 2014), Australia (Duffy et al 2013), Mexico (Perez and Ramírez 2015), Iran (Esmaeili et al 2015), Puerto Rico (Neal et al 2009), Philippines (Kottelat 2013), Japan (Ishikawa and Tachihara 2010), Italy (Piazzini et al 2010), Israel (Roll et al 2007), Indonesia (Sentosa and Wijaya 2013), Réunion (Keith et al 2006), Slovakia (Liptak et al 2016), Germany (Jourdan et al 2014) and Peru (Cossios 2010).…”