By Rocío González-Vaquero
Editor's note: While the NBSBC was created with a focus on the native bees of British Columbia, it has given us the opportunity to connect globally with other bee enthusiasts. This has allowed us to create connections and learn more about bee species worldwide. The following is a guest post from Dra. Rocío González-Vaquero, a biologist from Argentina. If you’d like to learn more about native bees in Argentina, you can follow her on Instagram and Facebook @abejasnativasargentinas.
Argentina, located at the southern tip of South America, is the home of more than 1100 species of wild bees. This country hosts a great variety of ecoregions. In the north, there is the arid Puna, Chaco, and the Yungas and Paranaense forests; to the south, there are woods of Nothofagus in the Andes and the windy Patagonian steppe. Other important ecoregions within Argentina include the wetlands, espinal, the rolling pampa grasslands, and the Argentine Monte. These distinct environments hold many endemic species: bees adapted to the local weather conditions which can only be found there. Much of the original ecosystem has been replaced by commercial agriculture, but a high diversity can still be found even in highly degraded areas like the rolling pampas. While sweat bees (Lasioglossum (Dialictus) spp. and augochlorines) sometimes outnumber other bees in agroecosystems (Le Feon et al. 2015), stingless bees (Meliponini) are among the most abundant species in the north.
Stingless bees are social and produce honey, like the honey bee (Apis mellifera). Though they lack a sting, some species can fiercely defend the vicinity of their nest by entangling the hair of the invader mammal, or by getting into the ears or nostrils. Due to these behaviors some receive the name of “enrolla cabello” (hair entangler) or “peluquerito” (little hairdresser). Stingless bees produce honey in smaller quantities than the domestic bee, but it is a valuable resource for rural communities since it is used to treat several illnesses, besides its mere consumption. These bees nest underground or in trees, and extractive exploitation is known to be frequent. The rational raising and handling of stingless bee hives for honey production, called meliponiculture, is a recent practice in the country (Roig Alsina et al. 2013).
Figure 1: Trigona spinipes, locally known as “carabozá” or “enrolla cabello”, is a stingless bee managed in Misiones (Argentina) for honey production.
Besides the honey bee there are a few exotic species in Argentina. One in particular, the bumble bee Bombus terrestris, threatens the survival of the native Bombus dahlbomii, known as “mangangá”, the largest bumble bee species on Earth. The European B. terrestris had been imported in Chile for crop pollination, crossed the Andes in 2006 carrying a seriously contagious pathogen (Arbetman et al. 2013), and recently reached the Atlantic coast. Native Argentinean bumble bees are trembling.
Figure 2: Bombus pauloensis sucking nectar from Salvia uliginosa (Lamiaceae) in the Botanical Garden “Lucien Hauman” in Buenos Aires city. This is one of the Argentinean species of bumble bee that may be at risk if populations of the exotic Bombus terrestris continue to expand in the country.
In Argentina there are several species that, besides pollen and nectar, collect oil from the flowers, which is used in nest construction or to feed their young. These bees have special hairs in the fore- and mid-legs to scrape and collect the oil from the plant. While gathering oil, Centris trigonoides pollinates Stigmaphyllon bonariense (Malpighiaceae) in the Eastern wetlands (Torretta et al. 2017). Some smaller species (Paratetrapedia spp.) also visit this plant, but they have a different approach: they collect the oil from below the flower, thus they do not pollinate but steal the resource! So unfair for the plant!
Figure 3: A female Centris trigonoides visiting a flower of Stigmaphyllon bonariense in the natural reserve “Costanera Sur” in Buenos Aires city. Photograph by Diana Torres.
Buenos Aires city and its suburban area constitutes the fourth-most populous city in the Americas (15.6 million people). Here houses (and their gardens) are being replaced by tall buildings and lawns every year, so now more than ever it’s essential to detect which plants are used by bees as resources. Promoting the planting of these species would help bee conservation enormously. For this reason, I’m currently studying the diversity of bees in Buenos Aires city, their interactions with native and exotic/ornamental flora, and if urban edible gardens can be edible for bees too! Sweat bees (Augochlora spp., Augochloropsis spp.), bumble bees (Bombus pauloensis), stingless bees (Plebeia spp.), leafcutter bees (Megachile spp.) and carder bees (Anthodioctes megachiloides) can be commonly found in urban gardens when native plants are abundant. Fortunately there is a small but growing interest to reconnect with nature, to grow native plants, grow plants to attract butterflies, or to place edible plants in pots in balconies and terraces. Since most people only know honey bees and bumble bees, I created the Instagram/facebook @abejasnativasargentinas to share pictures, curiosities and spread knowledge about the beautiful bees of this part of the world!
Figure 4: Augochlora amphitrite, a common species in Buenos Aires City, in a flower of Ipomoea indica (Convolvulaceae).
References:
Le Féon, V., Poggio, S.L., Torretta, J.P., Bertrand, C., Molina, G.A.R., Burel, F., Baudry, J. and Ghersa, C.M. 2015. Diversity and life-history traits of wild bees in intensive agricultural landscapes in the Rolling Pampa, Argentina. Journal of Natural History, DOI: 10.1080/00222933.2015.1113315
Roig Alsina, A., Vossler, F.G. and Gennari G.P. 2013. Stingless bees in Argentina. In: Vit, P, Pedro, S.R.M., Roubik, D.W. (eds.) Pot-Honey, a legacy of stingless bees. Springer.
Arbetman, M.P., Meeus, I., Morales, C.L., Aizen M.A. and Smagghe G. 2013. Alien parasite hitchhikes to Patagonia on invasive bumblebee. Biological Invasions, 15: 489-494. DOI: 10.1007/s10530-012-0311-0
Torretta, J.P., Aliscioni, S.S., González-Arzac, A. and Avalos, A.A. 2017. Is the variation of floral elaiophore size in two species of Stigmaphyllon (Malpighiaceae) dependent on interaction with pollinators? Plant Ecology & Diversity, 10(5-6): 403-418. DOI: 10.1080/17550874.2018.1434567