Ants in forests and grasslands in three ecoregions of Argentina
In the paper “Terrestrial ant assemblages (Hymenoptera: Formicidae) in protected forests and grasslands in three ecoregions of Corrientes Province, Argentina” published in Environmental Entomology, the authors Darío D Larrea, Matias I Dufek, and Miryam P Damborsky tested the habitat heterogeneity hypothesis in Argentina. This hypothesis predicts that species richness increases with environmental structural complexity. They collected 5,465 ants belonging to 37 species and their results did support the habitat heterogeneity hypothesis: More ant species were found in structured habitats (32 species in the forest) and fewer in grasslands (26 species). Here, first author Darío D Larrea shares some pictures and a video.
A Photoblog contribution compiled by Darío D Larrea
Extensive areas of the grasslands and forests studied during 2013-2014 are currently burned. From January-February 2022, extensive fires spread over more than 900,000 ha in the Argentinean province of Corrientes. Among the areas affected by the fire are grasslands, forests, forestries (pine and eucalyptus plantations), and wetlands, resulting in biological loss, which is difficult to assess.
Grasslands are among the main environments affected by these fires. Although plant and animal species in these biomes are well adapted to cyclic periods of natural burning, the time for recolonization is uncertain due to the extent of the area affected. Therefore, when accessing the area became safe, the Research Group on Arthropod Biology (GIBA, Spanish acronym) started a one-year-long, monthly sampling to assess the different groups of arthropods that survived the burnings and will subsequently colonize the areas affected. Ants are expected to be one of those few groups of arthropods that could have resisted such a catastrophe.
Environments where Formicidae species were captured in the Corrientes Province, Argentina (2013-2014). Humid Chaco ecoregion: A) Grassland. Espinal ecoregion, B) Forest, C) Grassland. Paranaense ecoregion, D) Forest, E) Grassland, F) Forest. (© M.I. Dufek pictures C, D, E, and F. © D.D. Larrea; pictures A and B; final composition)
Ant species collected in the Corrientes Province, Argentina. A) Neoponera villosa. B) Poneracantha triangularis. C) Dorymyrmex thoracicus. D) Acanthostichus kirbyi. E) Ectatomma edentatum. F) Camponotus sp2. (© D.D. Larrea.)
Geographic location of the study area in the Humid Chaco, Paranaense, and Espinal ecoregions, Corrientes Province, Argentina (2013-2014). Areas burned in 2022. (© D.D. Larrea)
Current state of grasslands after the fires in Corrientes Province (Argentina) in March 2022. (© D.D. Larrea)
Video: Leaf-cutter ants of the genus Acromyrmex grazing on sprouts (blades of grass) in one of the burned grasslands. (© D.D. Larrea)