Comparative Study of Functional Response of Common Hemipteran Bugs of East Calcutta Wetlands, India (original) (raw)

Influence of density on intraguild predation of aquatic Hemiptera (Heteroptera): implications in biological control of mosquito

The water bugs Diplonychus rusticus (Fabricius) (Heteroptera: Belostomatidae) and Anisops bouvieri (Kirkaldy) (Heteroptera: Notonectidae) co-occur in wetlands sharing mosquito larvae as prey. As a consequence, an asymmetrical intraguild predation (IGP) involving D. rusticus as IG predator and A. bouvieri as IG prey can be possible, the outcome of which may vary with the relative density of interacting species. Based on this proposition density dependent effects on the IG prey and shared prey mortality were assessed in the laboratory using varying numbers of IG predator and shared prey (IV instar Culex quinquefasciatus larva). In contrast to single predator system, mosquito larvae were proportionately less vulnerable to predation in IGP, at low density of shared prey. An increase in density of mosquito decreased the mortality of IG prey (A. bouvieri), but the mean mortality of the IG prey increased with the density of IG predator, in IGP system. Increase in density of mosquito and D. rusticus enhanced risk to predation of mosquito while reducing the mortality of A. bouvieri. Interaction between D. rusticus and A. bouvieri as a part of IGP system provides a possible reason of coexistence of mosquito immature along with predators in wetlands. ] in carryng out the work. SB acknowledges the financial assistance of UGC-RFSMS in carrying out this work.

Larvicidal Efficiency of Aquatic Predators: A Perspective for Mosquito Biocontrol

Zoological Studies, 2006

Ram Kumar and Jiang-Shiou Hwang (2006) Larvicidal efficiency of aquatic predators: a perspective for mosquito biocontrol. Zoological Studies 45(4): 447-466. Biological control of mosquito larvae with predators and other biocontrol agents would be a more-effective and eco-friendly approach, avoiding the use of synthetic chemicals and concomitant damage to the environment. Manipulating or introducing an auto-reproducing predator into the ecosystem may provide sustained biological control of pest populations. The selection of a biological control agent should be based on its self-replicating capacity, preference for the target pest population in the presence of alternate natural prey, adaptability to the introduced environment, and overall interaction with indigenous organisms. In order to achieve an acceptable range of control, a sound knowledge of various attributes of interactions between a pest population and the predator to be introduced is desirable. Herein, we qualitatively review a wide range of literature sources discussing the ability of different aquatic predators to control mosquito larval populations in environments where mosquitoes naturally breed. Different predators of mosquito larvae include amphibian tadpoles, fish, dragonfly larvae, aquatic bugs, mites, malacostracans, anostracans, cyclopoid copepods, and helminths. The most widely used biocontrol agents of mosquito populations are the western mosquito fish, Gambusia affinis, and the eastern mosquito fish, G. holbrooki. The effect of these fishes on native faunal composition and their inability to survive in small containers, tree holes etc., which are ideal breeding sites of vectorially important mosquitoes, make them inefficient in controlling mosquito populations. On the basis of larvicidal efficiency, the ability to produce dormant eggs, the hatchability of dormant eggs after rehydration, faster developmental rates, and higher fecundity, various tadpole shrimp can be considered to

Mosquito Prey Vulnerability in Intraguild Predation Between Ranatra filiformis and Anisops bouvieri: Implications in Biological Control

Wetlands are common habitats of a range of predatory water bugs (Heteroptera) constituting a guild that exhibit similar dietary choice including mosquito. Differences in body size and micro habitat preference among the heteropteran guild members provide a fair possibility of intraguild predation that can influence the regulatory effect on the prey species. This proposition was tested under laboratory conditions, using varying density of Ranatra filiformis (IG predator) and Anisops bouvieri (IG prey) as predators against mosquito larvae as shared prey. Compared to single predator system, mosquito larvae were proportionately less vulnerable to predation in intraguild predation (IGP), at low density of shared prey. In IGP system, vulnerability of shared prey increased with increase in density accompanied by a decline in mortality of IG prey. The mean mortality of shared prey and IG prey increased with the density of IG predator. It was apparent that the mosquito prey vulnerability was enhanced with increase in density of mosquito and R. filiformis while reducing the mortality of A. bouvieri partly. The interaction between R. filiformis and A. bouvieri as a part of IGP system indicate about the possible mechanism of coexistence of predators and prey in the wetlands. The density dependent effects on reduction and enhancement of shared prey (mosquito) mortality indicate that appropriate ratio of R. filiformis, A. bouvieri and mosquito larvae will be required to make biological regulation of wetland mosquitoes feasible.

Influence of competing and predatory invertebrate taxa on larval populations of mosquitoes in temporary ponds of wetland areas in Germany

Journal of Vector Ecology, 2010

Abundances of mosquito larvae and associated invertebrate communities were assessed in 27 temporary ponds during the spring season in wetland areas of Germany. Four genera of mosquitoes were identiied: Aedes, Anopheles, Culex, and Culiseta. We focused our analyses on Aedes spp. because this genus was the most abundant (92% of total abundance) and frequently encountered mosquito (present in 65% of investigated sites). he abundance of Aedes spp. was negatively associated with the abundance of competitors for food, and to a lesser extent with those of intraguild predators and strict predators. he inluence of these natural antagonists on larvae of Aedes was stronger in ponds with higher levels of dissolved oxygen (53 ± 4%) than in ponds with lower levels (16 ± 1%). he overall abundance of antagonists explained 42% of the variation in abundance of Aedes spp. at sites with higher levels of dissolved oxygen. Of this explained variation, competitors accounted for 34.7%, whereas the abundance of intraguild predators and strict predators accounted for only 6.8 and 0.5%, respectively. herefore, the promotion of competing species might be an appropriate ecological approach for the control of Aedes spp. in temporary ponds in these areas. Journal of Vector Ecology 35 (2): 419-427. 2010.

Biological mosquito control is affected by alternative prey

Zoological Studies, 2015

Background Mosquitofish were introduced to several countries of the tropics and subtropics as biological agents for the control of mosquito larvae. Meanwhile, they became a threat to native communities and fish worldwide, similar to other invasive species through resource competition, overexploitation, or habitat alteration. We investigated prey selectivity patterns of Gambusia affinis (mosquitofish) preying on larvae of the two Indian major carps (Catla catla and Labeo rohita) in the presence of varied proportions of alternative prey (rotifers, cladocerans, chironomid and mosquito larvae) under laboratory conditions. Results The patterns of prey selectivity in mosquitofish were influenced by the presence of alternative prey and their relative abundance in the environment. Carp larvae, when present in equal proportions, were randomly selected by mosquitofish, however, positively selected when present in higher proportions. In the presence of Hexarthra mira, Daphnia similoides or the...

Opportunistic foraging by heteropteran mosquito predators

Aquatic Ecology, 2010

Tropical aquatic environments host a large number of predatory insects including heteropteran water bugs Anisops bouvieri Kirkaldy, 1704 (Heteroptera: Notonectidae), Diplonychus (=Sphaerodema) rusticus Fabricius, 1781 (Heteroptera: Belostomatidae), and Diplonychus (=Sphaerodema) annulatus Fabricius, 1781 (Heteroptera: Belostomatidae) feeding on a range of organisms. In tropical and subtropical wetlands, ponds, and temporary pools these predators play a role in regulation of dipteran populations, particularly mosquitoes and chironomids. Their relative abilities to control mosquitoes depend in part on predator preference for mosquitoes in relation to other natural prey, and the predators' propensities to switch to mosquitoes as mosquito

Predatory efficiency of the water bug Sphaerodema annulatum on mosquito larvae (Culex quinquefasciatus) and its effect on the adult emergence

Bioresource Technology, 2004

The daily number of IV instar larva of Culex quinquefasciatus killed, rate of pupation and adult emergence was noted in presence of the predatory water bug Sphaerodema annulatum for a period of seven consecutive days, experimentally, in the laboratory. The rate of IV instar larva killed by the water bugs on an average was 65.17 per day. The rate of pupation ranged between 7.6 and 48 in control while in presence of water bugs it ranged between 6 and 35. The rate of adult emergence in control experiments varied between 1.4 and 4.8 per day, which was reduced to only 0.4-28.8 per day in case of the water bugs. The results clearly indicate that the water bugs on its way of predation reduces the rate of pupation and adult emergence of Cx. quinquefasciatus significantly which calls for an extensive field trials.

Assessment of the predatory capacity on mosquito larvae of Jenynsia multidentata (Anablepidae) in presence of vegetation under laboratory conditions

Iheringia, 2019

Larvivorous fish have been studied as potential biocontrol agents of mosquito larvae and pupae through their trophic interactions. The use of native fish for mosquito control may have benefits for both aquatic biodiversity and human health. Evaluating the effect of vegetation on the predatory efficacy is fundamental to determine if this species can be used as a biocontrol agent. With the aim of evaluating Jenynsia multidentata (Jenyns, 1842) as a biocontrol agent of Culex pipiens Linnaeus, 1758, we tested its predatory capacity in the presence or absence of aquatic vegetation under laboratory conditions. Two independent experiments were conducted. Larval consumption at a density of 60 larvae (6 larvae/l) was significantly reduced with the vegetation increased. On the other hand, when the larval density was 120 (12 larvae/l), the predatory capacity of J. multidentata did not vary in the presence or absence of vegetation. This result indicated that vegetation effect on consumption could be related to prey density, since at the higher density of prey the probability of predator-prey encounter might be increased. Jenynsia multidentata is a good consumer in presence of vegetation and could be used as a potential biocontrol agent of mosquito larvae in natural environments with similar characteristics to the ones tested in these experiments.

Aquatic insect predators and mosquito control

Tropical Biomedicine, 2009

Mosquitoes are serious biting pests and obligate vectors of many vertebrate pathogens. Their immature larval and pupal life stages are a common feature in most tropical and many temperate water bodies and often form a significant proportion of the biomass. Control strategies rely primarily on the use of larvicides and environmental modification to reduce recruitment and adulticides during periods of disease transmission. Larvicides are usually chemical but can involve biological toxins, agents or organisms. The use of insect predators in mosquito control has been exploited in a limited fashion and there is much room for further investigation and implementation.