Combining correlative and mechanistic niche models with human activity data to elucidate the invasive potential of a sub‐Antarctic insect

Abstract

Aim Correlative species distribution models (SDMs) are subject to substantial spatio‐temporal limitations when historical occurrence records of data‐poor species provide incomplete and outdated information for niche modelling. Complementary mechanistic modelling techniques can, therefore, offer a valuable contribution to underpin more physiologically informed predictions of biological invasions, the risk of which is often exacerbated by climate change. In this study we integrate physiological and human pressure data to address the uncertainties and limitations of correlative SDMs and to better understand, predict and manage biological invasions. Location Western archipelagos of the Southern Ocean and martime Antarctica. Taxon Eretmoptera murphyi (Chironomidae), invertebrates. Methods Mahalanobis Distances were used for correlative SDM construction for a species with few records. A mechanistic SDM was built around different fitness components (larval survival and life stage progression) as a function of temperature. SDM predictions were combined with human activity levels in Antarctica to generate a site vulnerability index to the assess colonization risk of E. murphyi. Future scenarios of ecophysiological suitability were built around the warming trends in the region. Results Both SDMs converge to predict high environmental suitability in the species' native and introduced ranges. However, the mechanistic model indicates a slightly larger invasive potential based on larval performance at different temperatures. Human activity levels across the Antarctic Peninsula play a key role in discerning site vulnerabilities. Niche suitability in Antarctica grows considerably under long‐term climate scenarios, leading to a substantially higher invasive threat to the Antarctic ecosystems. In turn changing conditions result in growing physiological mismatches with the environment in the native range in South Georgia. Main conclusions Long‐term studies of invasion potential under climate benefit from integrating correlative predictions with physiological experiments, as the invasion potential varies depending on the area and the timescale examined. This study also highlights a conservation paradox whereby the accidental introduction of an insect represents a threat to the Antarctic ecoystems that contrasts with its endangered status at the native range.

Spotlight on the invasion of a carabid beetle on an oceanic island over a 105-year period

“…With the species already having a wide distribution in parts of the archipelago, knowledge of its past and current distribution provide valuable insight into the environmental drivers of its geographic spread, and help identify suitable habitats vulnerable to colonisation by the species. This body of knowledge, which could serve for making predictions on future geographic expansion 104 , underpins the current urgent requirement to define and implement effective biosecurity measures (i.e. detailed inspection and cleaning of clothing, footwear, equipment, freight, vehicles and vessels) in concert with the management of the National Nature Reserve, in particular when visiting sites not yet colonized by M. soledadinus.…”

Distribution and Habitat Preferences of the Newly Rediscovered Telmatogeton magellanicus (Jacobs, 1900) (Diptera: Chironomidae) on Navarino Island, Chile

“…The data presented lay the foundation for future studies of this unusual insect’s distribution, ecology, phenology, physiology and general biology. With improved knowledge of the species’ preferred microhabitats, we are better able to predict other locations where it may occur, and even to extrapolate the risk of it being transported elsewhere (e.g., in species distribution modelling, which can involve the direct use of GIS data or a combination of biogeographical, physiological and meteorological data [ 33 , 60 , 61 , 62 ]).…”

“…This group includes Belgica antarctica Jacobs (1900), endemic to the Antarctic Peninsula and South Shetland Islands [ 24 , 25 , 26 ], and Eretmoptera murphyi Schaeffer (1914), originally described from and endemic to sub-Antarctic South Georgia and now introduced to the maritime Antarctic Signy Island [ 27 , 28 , 29 , 30 , 31 ]. Everatt et al [ 32 ] concluded that the latter species was pre-adapted to harsher conditions than what currently prevail in its native South Georgia, where it is now known to be palaeoendemic [ 24 , 25 ] and, therefore, has the potential to invade the Antarctic Peninsula region [ 33 ].…”

Antarctic: Climate Change, Fisheries, and Governance

“…For example, the presence of balanomorph barnacles and live individuals of the cosmopolitan pelagic barnacle, Conchoderma auritum, demonstrated the potential for non-native species to be transported to Antarctica this way (Hughes and Ashton 2017). Increasingly, modeling approaches are being used to predict potentially wide ranging future changes in distribution of both native and non-native terrestrial species in Antarctica (Bartlett et al 2020;Contador et al 2020;Hughes et al 2019;Pertierra et al 2017Pertierra et al , 2020.…”