Macroinvertebrate biomonitoring in Latin America: Progress and challenges

Macroinvertebrates are used as bioindicators worldwide, but the high diversity of macroinvertebrate species and endemism in Latin America (LA) requires greater knowledge of this group to increase the effectiveness of biomonitoring. We examined some of the primary taxonomic and ecological studies on macroinvertebrates in the region, quantified the number of papers that used foreign and local indices, examined alternative approaches to bioassessment that may be more relevant for the region, and explored freshwater ecosystem management in LA. Here, we highlight the need to increase taxonomic knowledge and the number of specialists in local fauna, establish and maintain taxonomic collections in public institutions, and make online databases on the biodiversity in each country available. However, we also demonstrate that taxonomy specialists of different nationalities do collaborate on the generation of fundamental information about biodiversity in LA. We found that 57% of the 215 reviewed scientific articles from LA used foreign but locally adapted indices for biomonitoring aquatic ecosystems. Only 21% of these articles presented local indices developed in LA. New technologies, such as environmental DNA, offer substantial potential for bioassessment but only in regions where sufficient taxonomic knowledge exists and where species-level stressor-response relationships are well described. In the absence of more complete taxonomic records, there could be some value in developing biological trait and multimetric indices, and occupancy models could be developed to analyze the relationship between taxa and stress factors. These tools could be adopted by researchers to generate more accurate biotic indices based on local taxa. Finally, in LA, bioindicators are used to support scientific research more often than as environmental monitoring tools. Environmental laws and regulations that support the biomonitoring of LA freshwaters and unified criteria for evaluating and monitoring aquatic ecosystems are essential to face regional and global challenges.