Control and eradication efforts of aquatic alien fish species in Lake Caicedo Yuso-Arreo

Abstract

Management of invasive species, whether prevention, population reduction, or eradication, requires assessment of the invasive species' population status and an assessment of the probability of success of management options. Perceptions of a species' permanence in an environment or lack thereof frequently drives how limited time, financial, and personnel resources are allocated to such efforts. Language we use to describe a non-native species' status largely defines these perceptions and sets boundaries, real or perceived, to potential management actions. Here we discuss the use of a particular term-"established"when confronting management decisions for invasive species. Our objective is to contribute to bridging the gap between the realms of conceptual development and management with respect to use of the term "established". We find that although there are benefits of polysemy and synonymy to conceptual development they present an additional challenge to managers who must weigh the costs, benefits, and potential for success of particular management actions. We also examine how existing conceptual frameworks might be augmented to bridge the theoretical-practical gap, such as more precisely defining potential management actions and explicitly including assessment of risk.

Using stable isotopes to analyse extinction risks and reintroduction opportunities of native species in invaded ecosystems

“…The ecological consequences of aquatic invasions have gained substantial attention in recent decades 1 , 2 . Whilst previous research has addressed species-specific invader impacts on native species 3 – 5 , ecosystems 6 , 7 , ecosystem services 8 or mechanisms underlying invasions 9 – 11 , attention is now shifting towards impacts on entire communities and complex species interactions 6 , 12 – 14 .…”

“…To test the suitability of stable isotope analysis to better understand invasive species’ impacts on native communities, a simplified study system is required, such as the invaded community of Arreo Lake (Spain). Prior to 1990, various taxa of native fish and invertebrates were present in Arreo Lake; however, they are now considered extirpated or locally extinct 5 . Among these, some are of regional concern: the European eel Anguilla anguilla Linnaeus , 1758 (considered extirpated after 2000), the endemic whirligig beetles Gyrinus sp.…”

“…The protected area of Arreo Lake was not utilized for angling nor changed in terms of water quality 33 , 38 , but non-native fish and crayfish species introductions likely relate to introductions from illegal anglers or the live-bait pathway (Table 1 ). The resultant non-native species community is characterised by high linkage density and connectance in the food-web due to its strong trophic interactions and predator-prey relationships 5 , 33 . In particular, in the last decade, the community and habitat of Arreo Lake has substantially changed through the loss of native fishes and macrophytes.…”

“…In particular, in the last decade, the community and habitat of Arreo Lake has substantially changed through the loss of native fishes and macrophytes. Particularly the presence of the crayfish Procambarus clarkii has led to disruptions of the habitat and the native flora, leading to the dominance of Phragmites australis and Cladium mariscus ; both non-native plants 5 .…”

“… Group Species First detected Reference Pathways Non-native species Fish Micropterus salmoides 1994 39 Angling Lepomis gibbosus 2005 38 Cyprinus carpio 2010 38 Crayfish Procambarus clarkii 1998 38 Aquaculture Plants Phragmites australis 1998 5 Unknown Cladium mariscus 1998 5 Group Species Extirpation date Reference Pathways Native species Fish Anguilla anguilla 2000 5 Not applicable Tinca tinca 2013 5 Not applicable Crayfish Austropotamobius pallipes 2014 5 Not applicable Insects Gyrinus sp. 2008 …”