Since the late 19th century, exotic ladybirds (Coleoptera: Coccinellidae) have been used extensively for suppressing herbivorous insects of economic importance. In recent decades, the introduction of non-native biological control (BC) agents has been greatly limited due to the awareness of the potential non-target effects of introductions. Nonetheless, recent episodes of biological invasions of economically important pests have raised the need to carefully consider whether the expected benefits of pest control go beyond the possible environmental risks of introduction. To better understand the factors that contributed to successful BC programs, here we review the literature behind classical and augmentative BC using exotic ladybirds. Additionally, by means of case studies, we discuss the BC efficacy of selected exotic species, e.g., Coccinella septempunctata L., Harmonia axyridis (Pallas), and Hippodamia variegata (Goeze), and their position within the communities of predators in the introduced areas of USA, Canada, and Chile. In Europe, much of the research on exotic ladybirds has been conducted on the undesired impact of H. axyridis. Therefore, we summarize the risk assessment data for this species and review the field research investigating the ecological impact on European aphidophagous predators. According to the BIO-CAT database of classical BC programs, 212 ladybird species belonging to 68 genera have been released in about 130 years of BC activity, with 14.6% of introductions having resulted in partial, substantial, or complete control of the target pest. However, because post-release evaluation of establishment and BC success has not always been conducted, this rate could underestimate the successful cases. Among other factors, ladybird establishment and pest suppression mostly depend on (1) intrinsic factors, i.e., high voracity, synchronized predator-prey life cycle, and high dispersal ability, and (2) extrinsic factors, i.e., adaptability to the new environment and landscape composition. This review contributes to improved understanding of ladybirds as exotic BC agents.

No abstract

Decomposition of human remains is a complex process impacted by many intrinsic and extrinsic factors. A less-studied extrinsic factor in forensic taphonomy are the scavengers that consume soft and hard tissue. Scavengers physically degrade and remove soft tissue, disperse, and destroy skeletal elements, which can make locating remains challenging. While invertebrate activity has been largely investigated, there is limited quantitative data available on vertebrate activity, particularly in Canada. This study aimed to determine which species (vertebrate and invertebrate) belong to the scavenger guilds in southern Quebec, and their potential taphonomic impact on the decomposition process. Two independent trials were conducted in 2020 using pig carcasses: one during summer in a forest habitat and one during fall in a grassland habitat. Each carcass was placed a minimum 100 m apart in semi-rural land. Vertebrate scavenger activity was recorded by continuous surveillance using trail cameras. Carcasses were also regularly visited to monitor the decomposition process and the activity of invertebrate scavengers. Overall, the vertebrate scavenger guilds included a narrow range of corvids, turkey vultures, coyotes, and skunks. The intensity of vertebrate scavengers was greater in the grassland habitat (fall), while the intensity of invertebrate scavengers was greater in the forest habitat (summer). With the exception of invertebrate scavengers, very few species visited during the fresh stage of decomposition, and the probability of body displacement increased as decomposition progressed. These results identify which scavengers have the greatest taphonomic impact and highlight the importance of incorporating scavenger impact when searching for human remains.

No abstract

No abstract