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Gold mining is a major driver of Amazonian forest loss and degradation. As mining activity encroaches on primary forest in remote and inaccessible areas, satellite imagery provides crucial data for monitoring mining‐related deforestation. High‐resolution imagery, in particular, has shown promise for detecting artisanal gold mining at the forest frontier. An important next step will be to establish relationships between satellite‐derived land cover change and biodiversity impacts of gold mining. In this study, we set out to detect artisanal gold mining using high‐resolution imagery and relate mining land cover to insects, a taxonomic group that accounts for the majority of faunal biodiversity in tropical forests. We applied an object‐based image analysis (OBIA) to classify mined areas in an Indigenous territory in Guyana, using PlanetScope imagery with ~3.7 m resolution. We complemented our OBIA with field surveys of insect family presence or absence in field plots (n = 105) that captured a wide range of mining disturbances. Our OBIA was able to identify mined objects with high accuracy (>90% balanced accuracy). Field plots with a higher proportion of OBIA‐derived mine cover had significantly lower insect family richness. The effects of mine cover on individual insect taxa were highly variable. Insect groups that respond strongly to mining disturbance could potentially serve as bioindicators for monitoring ecosystem health during and after gold mining. With the advent of global partnerships that provide universal access to PlanetScope imagery for tropical forest monitoring, our approach represents a low‐cost and rapid way to assess the biodiversity impacts of gold mining in remote landscapes.

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Signals vary in type and function. However, regardless of the signal, effective transmission and receiver detection are needed to exist for communication. This chapter focuses on a review of visual color signals used by plants to attract pollinators. Signal detection work has intensely focused on epigamic signals; therefore, this review adds to the body of knowledge on nonsexual signal communication. In this review, we investigate visual signals as it relates to pollinators. We focus specifically on visual color signals used by Angiosperms flowers, both static and dynamic, and look at their Heliconiid pollinators as these butterflies provide a perfect organism for studies on floral signal use and pollinators’ behavior. We noted that many of these butterflies have three specifically distinct rhodopsins used to identify food and oviposition sites and some have more due to selective pressures of conspecific and mate identification as such they have served as the focal organisms of numerous genetic and ecological studies as they use color signaling in all aspects of their lives. This review further shows that although their color preferences related to feeding, ovipositing, and mate selection have been demonstrated in countless studies, there are gaps in invertebrate literature, as research on the relationships among signal use, evolution, dynamic signals, effects of signals changes on decision making and thus behavior have not been carried out to a large extent.

Abstract. Dasrat CM, Maharaj G. 2021. Biological control of mosquitoes with odonates: A case study in Guyana. Nusantara Bioscience 13: 163-170. Mosquitoes have plagued the lives of tropical residents as pests. However, due to their role as vectors of life-threatening diseases, controlling their population is necessary, especially in areas of prevalence – the Caribbean and Equatorial regions. In Guyana, we employ chemical treatments sub-regionally to eradicate mosquitoes. However, this treatment has limited success and is harmful to the environment. Therefore, our study focused on an environmentally friendly method such as biological control. This study was conducted at the University of Guyana, Turkeyen campus, where we exploited Odonata; Anisoptera, and Zygoptera as natural predators of mosquitoes of the genus Culex. The feeding efficiency and behaviors of naiads from the families of Libellulidae and Coenagrionidae were assessed during April – May of 2018. Each naiad was fed three Culine pupae and larvae, then observed for 60 minutes. We found that both groups pursue soft-bodied larvae and Libellulidae naiads are more efficient predators due to the higher feeding rate than Coenagrionidae. This finding is related to a behavioral study where we observed Libellulidae as active hunters that masticate and consume faster than Coenagrionidae, which are lay and wait, opportunistic predators that swallow their prey. We concluded that Libellulidae is an efficient predator for mosquito larvae of the Culex genus, and we found that there is a link between morphologic characteristics and feeding behaviors. We hope to use these results as a baseline study to develop mosquito biological control in Guyana. These can be used to reduce mosquito populations and the occurrence of vector diseases as well as improve integrated pest and vector management.

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This purpose of this paper is to review and evaluate published literature on the biology and chemistry of lichens and their ecological, ethnopharmacological, pharmaceutical and therapeutic potential. A systematic method was used to gather literature on “the biology and chemistry of lichens and their ecological, ethnopharmacological, pharmaceutical and therapeutic potential.” A total of fifty-five research papers published between the years 1963 to 2022 were selected and utilized for this review. Tables were used to present the results. The subtopics were then chosen using a subjective method: lichens and their benefits/ importance. In this paper, eight (8) ecological functions and fourteen (14) pharmaceutical properties and therapeutic potentials were evaluated and presented. Lichen biology and chemistry and their roles in ethnopharmacological are also discussed. Additionally, lichens as pioneer and keystone species and their role as bioindicators to assess ecosystem health, sustainability and productivity was also addressed in this research. The published papers established that lichens have many benefits and importance, they are capable of synthesizing a range of chemicals that are beneficial to us and they are used in both traditional and pharmaceutical preparation of different treatments to combat many different diseases that affect human beings. More studies to investigate the uses of lichens should be done, especially in neotropics as there is a paucity of data and in this biodiversity rich region.

Plants communicate with their pollinators through an astonishing range of signals that serve as either honest or deceptive cues which draw in and inform potential visitors of possible rewards. In wild type sweet sage, Lantana camara, floral colour signals were associated with nectar volume and sucrose concentration, and many pollinator taxa quickly learned to associate these varying colour signals with rewards. We tested the hypothesis that if sweet sage is employing a generalist pollinator strategy based on a trichromatic changing floral presentation system of honest rewards for pollinators, then the following predictions will be realized: 1) pre-change yellow flowers will be visited more frequently by pollinators than post change orange, or red flowers; 2) pre-change yellow flowers will produce higher quality and greater quantities of sucrose rewards than post-change orange, or red flowers; 3) inflorescences with higher ratios of rewarding flowers to unrewarding flowers are more attractive at short distances; and 4) inflorescences with a combination of pre-change rewarding and post-change rewarding and unrewarding flowers will act as a multi-coloured advertising billboard and as such be most attractive at long distances. We found corroboration for all of the aforementioned predictions. Thus, sweet sage evolved a generalized pollination visitation system based on honest signalling―of reward quantity and quality tied to colour changing visual signals acting in consort to produce a billboard that was easily perceived and deciphered. These resulted in high visitation rates by many different taxa of pollinators, thus contributing to higher individual plant fitness.