No abstract

  Se estudiaron las comunidades de peces en 12 jagüeyes, en función del uso del suelo dado a la zona de captación (agrícola, ganadero y urbanístico), en los municipios de Magangué, Bolívar y Los Palmitos, Sucre. Se capturaron 5695 individuos pertenecientes a nueve familias y cinco órdenes y 13 especies: Hoplias malabaricus, Curimata magdalenae, Astianax fasciatus, Piaractus brachypomus, Roeboides dayii, Prochilodus magdalenae, Hoplosternum thoracatum, Hemiancistrus wilsoni, Caquetaia kraussii, Oreochromis spp., Andinoacara latifrons, Poecilia caucana, Synbranchus marmoratus. Los jagüeyes con mayor riqueza y abundancia fueron los de uso urbanístico con 11 especies y 2512 individuos, seguido del ganadero con siete especies y 2252 individuos, con aplicación de la Prueba F, no existe una diferencia estadísticamente significativa entre las medias de las tres variables con un nivel de confianza del 95,0 %, con un p= 0,54 para A. fasciatus y 0,47 para A. latifrons, p ≥ 0,05. El grado de recambio de especies  (diversidad β) entre los jagüeyes y los tres usos dados a su zona de captación fue alto, porque la diferencia en la composición del ensamblaje de peces entre hábitat varía considerablemente, de 13 especies registradas  compartieron entre dos y cuatro especies, con valores de complementariedad entre el 50 y 67 % (agricultura), 20 y 50 % (ganadería) y entre el 50 y 86 % (urbanístico), la similitud fue alta en los jagüeyes de uso ganadero. La riqueza y abundancia de peces en jagüeyes encontradas en este estudio tiene una gran significancia ecológica en la conservación y preservación de la diversidad biológica íctica en las sabanas y Bosque seco Tropical en los departamentos de Sucre y Bolívar muy a pesar de la presión ejercida por la contaminación orgánica e inorgánica, producida por las actividades: agrícola, ganadera y urbana.

The transformation of forests into agricultural and livestock systems negatively affects the ecological dynamics and the ecosystem services provided by different groups of insects, including dung beetles, which stand out for their importance in recycling livestock dung. Since the 1980s, farmers in different regions of the world have been using Ivermectin to control parasites that affect cattle. The main route of elimination of this molecule and its metabolites is through manure, which affects the richness, abundance, and biomass of dung beetles when they use dung from treated animals. To quantify this effect, we carried out an experimental design in the field in the Colombian Caribbean, where nine cattle farms were evaluated, of which three were taken for each of the different cattle management practices most used in the region: (i) Ivermectin not applied, (ii) two doses of Ivermectin at 1% applied per year and (iii) two doses of Ivermectin at 3.15% applied per year. To assess the richness, abundance, biomass, and functional groups of dung beetles, during the dry and wet seasons, 30 pitfall traps were baited on each farm with fresh cattle manure with the same management doses described above. A total of 25,441 individuals belonging to 19 genera and 30 species were collected. The richness, abundance, and biomass of beetle assemblages decreased along the gradient represented by management without using Ivermectin and management where Ivermectin was used. Paracoprid beetles were the functional group that was most negatively affected in cattle farms with Ivermectin use. In cattle farms where Ivermectin was not used, there was a greater diversity and higher functional structure of dung beetle assemblages than in those where this veterinary medicinal product was used. Using Ivermectin generates short- and long-term effects on the richness, abundance, biomass, and functional groups of dung beetles in livestock systems in the Colombian Caribbean. Therefore, we suggest using integrated treatment management to prevent the recycling fauna from being affected.