Economic costs of biological invasions in protected areas worldwide - where do we stand?

Abstract

Biological invasions are one of the main threats to biodiversity within protected areas (PAs) worldwide. Meanwhile, the resilience of PAs along with their capacity to mitigate impacts from invasions remains largely unknown. Filling this knowledge gap is therefore critical for informing policy responses and optimally allocating resources invested in prevention and control strategies. Here we use the InvaCost database to address this gap from three perspectives: (i) characterizing the total cost of invasive alien species (IAS) in PAs; (ii) examining differences in mean observed costs of IAS between PAs and non-PAs; and (iii) evaluating factors affecting mean observed costs of IAS in PAs. Our results show that reported economic costs of IAS in PAs amounted to US$ 22.13 billion between 1976 and 2020, of which US$ 802.47 million were observed costs (incurred) and US$ 21.18 billion were potential costs (expected). The highest observed total costs were reported for Africa and South America; mainly caused by mammals, plants and insects; and predominantly impacted the finances of government agencies. Most of the observed total costs were reported for management (69%) versus damage (27%), however, the vast majority of management costs were reported for post-invasion actions (US$ 453 million; focused on control and eradication). PAs incurred on average higher costs than non-PAs, however, this was dependent on the environment and the continent. When analyzing costs of IAS within PAs, observed mean costs significantly differed with the environment (higher in terrestrial environments), continent (higher in Pacific islands), taxon (higher for vertebrates and invertebrates than in plants) and the human development index (developed countries incur higher costs). Managers of selected PAs surveyed acknowledged IAS as the most threatening factor, concurred on the necessity of reporting costs in PAs, and pointed to insufficient budget allocation for pre-invasion actions. Our findings highlight the need for a deeper understanding of the economic costs caused by invasions across PAs, direct driving factors and management challenges.

Economic costs of invasive alien species in Spain

“…Moreover, Capdevilla-Argüelles and Gallardo (2019) ranked a set of top-invaders by their menace to the Spanish national parks and some of those that constituted the highest menace, are amongst the ones we reported here with the highest costs, such as E. crassipes, Cenchrus setaceus, N. vison, V. velutina or Cortaderia selloana. Furthermore, Moodley et al (2021) classified Baccharis halimifolia and V. velutina among the costliest species in European protected areas, while N. vison was among the costliest in semi-aquatic environments within protected areas (B. halimifolia was ranked 11 th in Spain when looking only at management costs). However, it could be that our data are conservative regarding the real costs incurred in protected areas.…”

Invasive alien plants in Bangladesh: taxonomic inventory, impact assessment and management issues

“…So far, data on invasive plant species in Bangladesh have not been taken into account in the more and more frequently appearing global comparisons and analyzes (Dawson et al 2017), while there are ants (7 species), sh (8), birds (1) and mammals (6). On the other hand, it is plants that are credited with large losses in ecosystems and high possible costs of their removal (Moodley et al 2021). In general, invasive alien plants are studied relatively often (Warren II et al 2017), as they can dominate or degrade many ecosystems compared to other taxonomic groups (Pyšek et al 2017).…”

Managing an invasive tree in coastal dunes: The importance of follow-up treatments to improve the recovery of protected habitats

“…Invasive alien species are the fifth major threat to biodiversity worldwide (IPBES, 2019) and present a major challenge to the managers of protected areas that often have limited funds for the conservation of biodiversity (Pyšek et al, 2013). Despite economic assessments and reporting of invasive alien species in protected areas being relatively scarce, it is clear that post-invasion management represents the highest proportion of the observed costs (Foxcroft et al, 2013;Moodley et al, 2022). Therefore, management of invasive alien species is often hampered by the shortage of economic resources and also by the lack of clear policies and specialized staff (Braun et al, 2016;Paganelli et al, 2021).…”