Abundance Of Insect Species Research Articles

Insect community structure in young and productive coffee farms under leucaena shade of Jember Regency, East Java, Indonesia

The developmental phase of Robusta coffee plantations with agroforestry systems exhibits varying ecosystem characteristics (biotic and abiotic), therebyinfluencing the dynamics of insect community composition within them. One of the major coffee-producing centers in East Java is Jember Regency, where coffeecultivation commonly employs agroforestry systems with various shade trees. Understanding the abundance of insect species in agroforestry coffee plantations is important for determining insect pest control measures. This research aims to study the insect community structure in young coffee and productive coffee farms. Insect sampling was conducted in young coffee farms and productive coffee farms at the Kaliwining Experimental Station, Indonesian Coffee and Cocoa Research Institute (ICCRI), by using road sampling methods with insect nets and pitfall traps. Both types of plantations utilize Leucaena sp. var L2 as shade trees, forming agroforestry coffee plantation systems. Data analysis was performed by calculating the Shannon-Wiener diversity index (H’) to assess insectdiversity and the independent sample t-test to determine differences in insect abundance based on functional roles between the two farms. The results indicatethat the composition and abundance of insects in productive coffee farms are higher than in young coffee farms, resulting in a higher insect diversity index valuefor productive coffee farms (categorized as high), while young coffee farms fall into the moderate category. Furthermore, based on their functional roles, productive coffee farms positively influence the abundance of herbivorous, predatory, parasitoid, and detritivorous insects.

A Survey on the Diversity of Field Insect Pests of Okro (Abelmoschus Esculentus) within the Six Adp Zones in Akwaibom State

A survey was conducted to determine the diversity and abundance of insect pests associated with okra (Abelmoschus esculentus) across the six Agricultural Development Programme (ADP) zones in Akwa Ibom state namely; Uyo, Abak, Eket, Ikot ekpene, Etinan and Oron using multi – stage random sampling technique, swoop nets for flying insects, aspirators for collecting tiny insects, pair of forceps and hand picking for larvae and slow moving insects. A total of 634 insects were collected across the six zones and identified into 4 orders, 13 families and 15 species. The dominant order by specie was Hemiptera having (6/40%) followed by Lepidoptera (4/26.67%), Coleoptera (3/20%) and the least was Orthoptera having (2/13.33%) while dominant order by individuals was Coleoptera having 279/44.01%), followed by Hemiptera (244 /38.49%), Lepidoptera (68/10.73%) and the least was Orthoptera (43/6.78%). Dominant insect specie across the six zones was Flea beetle (Podagrica sp.) with total population of 185 followed by Aphids (Aphis gossypii - 98) and the least was Cabbage looper (Trichoplusia ni – 7). Diversity index result showed that Eket zone had the highest no. of individuals (122) with the least no. of species (12) and least Shannon index value (H_ 2.11) followed by Oron zone with 112 individuals, no. species (13) and shannon index ( H_2.31). Uyo zone had the least no. of individuals (93), no. species (13) and Shannon index (H_2.21) while Ikot ekpene zone had the highest Shannon index value (H_2.34) and highest no. of species (14) with no. of individual (101). This study reveals that there is high diversity and abundance of insect species attacking okra in Akwa Ibom State hence drastic control measures is imperative for successful and profitable production of Okra.

Insect diversity and abundance in three forest areas of Lagos State

Mangrove forest ecosystem preserves diversity of species, which includes insects. Insects serve as bioindicators, pollinators and nutrient recyclers in the forest. However, the number of insects decline as the forest fades. We conducted this field survey to assess the diversity and abundance of insect species in three selected mangrove swamp forests located in Lagos State, Nigeria. Samples were collected fortnightly using different techniques, for a period of three months. Insects collected were preserved in 70% alcohol, but butterflies and moths were preserved dry. Representative samples were identified with picture insect mobile application V1.0.8 and confirmed using standard identification keys. Vegetation cover was quite similar in all the areas sampled comprising of Alchornea cordifolia, Eragrosis racemose, Paspalum dilatatum and Avicennia germania. A total of 182 insects were collected belonging to seven Orders, 18 Families and 38 species. The most dominant Order was Coleoptera with relative abundance of 66.48% and the least was Hemiptera (0.59%). The Order Odonata was the most diverse (HꞋ=1.09), and the most dominant species were Pantala flavescens and Sympetrum fonscolombii, having relative abundance of 8.24% each, followed by Palpopleura lucia (7.69%), Ceriagrion glabrum (7.14%) and Lestinogomphus africanus (6.04%). Psedagrion kersteni was rare with relative abundance < 0.5%. Iba site had the highest species diversity (HꞋ=1.24) but lowest number of individuals. This study documents the diversity and abundance of insects in the fast-disappearing mangrove forest of Lagos State, Nigeria.

Agronomic characteristics, insect pollinators, and seedbank persistence of a novel oilseed crop, chia (Salvia hispanica L.) in eastern China

Chia (Salvia hispanica L.), a member of the Lamiaceae family, is a newly emerging crop species in China, gaining extensive attention worldwide as a potential dietary oil and pharmaceutical resource. However, there are few reports on the cultivation or field evaluation of chia in China. The present study was conducted to evaluate the agronomic performance of chia, including the determination of the suitable seeding window and seed yield potential. Data were also collected on flower-visiting insects, flowering phenology, and seedbank persistence of chia for providing baseline information on weed risk assessment for the potential of crop introduction in China. Results showed that chia seeded between late-Apr. and middle-May produced a greater seed yield (mean: 686.6 kg ha−1; ranges: 324.5–1034 kg ha−1) compared to that of seeded at other dates (mean: 136.6 kg ha−1; ranges: 0–311.0 kg ha−1). While the content of individual saturated and unsaturated fatty acids of the chia seed oil varied with seeding date and genotype, the unsaturated fatty acids, including C18:1 (oleic acid), C18:2 (linoleic), and C18:3 (linolenic) were the most abundant fatty acid in chia seed oil, accounting for approximately 87 % of the total oil content. At the present location, even though the chia seeding dates varied from mid-Mar. to end-Jun., the plants could still complete the whole crop lifecycle with similar dates for the specific phenological stage. Moreover, chia flowers attracted a diverse group of pollinating insects from the Hymenoptera, Diptera, Lepidoptera, and Coleoptera. Eastern honeybees (Hymenoptera) and syrphid flies (Syrphidae) were the most abundant insect species, accounting for 25.4 % and 25.8 % of all insect pollinators, respectively. While the chia cannot persist in the seedbank during the spring growing season, the seeds from the late fall harvest could be partially dormant in the soil seedbank with the potential for generating the weed control problem in the subsequent crops. The baseline information obtained from this study would help understand the potential ecological risk of chia and serve a valuable reference for introduction of chia production in China.

Investigation of insect population density, species composition and associated losses in chickpea seeds stored on farms in Ethiopia

This survey aimed to investigate the extent of insect infestations, associated losses, and insect species abundance in farm-stored chickpea seeds across five chickpea growing districts in Ethiopia. Despite being the largest producer, consumer, and exporter of chickpea in Africa, insect pest infestations have caused significant losses to Ethiopia's chickpea industry. Results showed that Callosobruchus chinensis (L.) was the most prevalent insect species, followed by Sitophilus oryzae (L.) and Tribolium confusum (J. du Val). The insect pests infested both local and improved chickpea varieties, and traditional containers and polypropylene bags were used for storage. The percentage of insect-damaged seed ranged from 4.61% to 14.48%, while the seed weight loss ranging from 1.13% to 4.55%. The range of seed germination percentages was from 65% to 88%, with a mean rate of 71%. These losses significantly affect the market value of the crop as grain and its use as seed, affecting farmers' income and food security. Therefore, it is crucial to develop effective solutions to prevent the loss of farm-stored chickpea in Ethiopia.

High Biodiversity and Low Dominance in Insect Species on Marsegu Island: A Case Study

This study aimed to assess the diversity and abundance of insect species in the coastal forest of Marsegu Island in the Western Seram Regency. The data was collected using an exploratory method, which involved direct observation and sampling in the field between October 2020 and the completion of the study. A total of 321 individuals representing 20 species from six orders (Orthoptera, Hemiptera, Lepidoptera, Coleoptera, Diptera, Aranae) were identified, distributed across 20 families. The Diptera family Muscidae was most commonly found. The insect diversity index (H') was 4.371, indicating high species diversity within the region. The evenness index (E) was 0.931, suggesting that no single family dominated the population due to a balanced ecosystem. The dominance index was 0.155, implying low dominance and equitable abundance among species. The findings emphasize the importance of Marsegu Island's ecological balance, which may be threatened by chemical interventions. It is crucial to conserve these diverse and abundant insect communities, which play a significant role in maintaining ecosystem health and complexity.
 Highlights:
 
 
 
 
 The study revealed a high diversity of insect species (H' index = 4.371) on Marsegu Island, highlighting its rich ecological complexity.
 The even distribution of insect species (E index = 0.931) underlines the balanced ecosystem, free from chemical interventions.
 Despite the high diversity, no species dominates the ecosystem, as reflected by a low dominance index (0.155), emphasizing the importance of species equality in maintaining ecosystem health.
 
 Keywords: Insect Diversity, Marsegu Island, Ecosystem Balance, Species Abundance, Dominance Index.
 
 

Keragaman Serangga pada Tanaman Terong Ungu (Solanum melongena)

Indonesia as a mega-biodiversity country has a very diverse diversity of insects. The diversity of these insects has both beneficial and detrimental roles. The beneficial role of insects is that they act as pollinators, predators of pests and regulators of wild plant populations, while the detrimental roles of insects are plant-eating pests and disease vectors in plants. Insects have many habitats, one of which is purple eggplant or solanum melongena. Eggplant is cultivated for consumption and contains many ingredients. This plant is widely cultivated because it contains nutrients consisting of minerals and vitamins such as A, B and C, is low in calories and fat, and contains some protein, fiber and carbohydrates. This research is included in the quantitative descriptive research. This research is located on the agricultural land of PT. BIO, which is located at Jl. Banjar Sari No. 38, Dusun Awisurat, Tanjungsari, Kec. Tanjungsari, Sumedang Regency, West Java and takes place for 2 weeks in November 2022. Insect data collection uses insect nets and data that can be analyzed using relative abundance and Shannon-Wiener diversity index values. The insects found consisted of 6 orders namely Diptera, Hemiptera, Coleoptera, Orthoptera, Mantodea and Hymenoptera. The six orders consist of 9 families. The eggplant planting area has a Shannon-Wiener diversity index value of 1.8 so that the planting area conditions are close to natural conditions with an index value of > 2. From the findings, insects can be classified into four groups based on their role in eggplant plants. Based on their roles, six pest species, three predator species, one pollinator species and one non-pest species. The abundance of insect species in eggplant planting fields has low criteria except for Henosepilachna vigintioctopunctata which is moderate. The level of insect diversity in purple eggplant plantings was moderate, with the species that had the highest abundance being Henosepilachna vigintioctopunctata

Diversity assessment of insect species in the Kariavattom campus, University of Kerala

Insects play crucial roles in their specific niches and are vital contributors to various ecosystem processes. They dominate the food webs of both terrestrial and aquatic ecosystems. A study was conducted at Kerala University to evaluate the diversity and abundance of insect species in selected habitats (North and South campus). Sampling was conducted using pitfall traps, sweep nets, beating sheets, Berlese funnels, and hand collection. The collected insects were brought back to the laboratory for identification and counting. A total of 965 insects from 9 Orders and 35 Families were recorded. Indices such as the Shannon index, Simpson index, Margalef index, Evenness index, and Sorenson similarity index were utilized to analyze the diversity of insects. The results indicated that Hymenoptera (30.155%), Orthoptera (25.596%), Lepidoptera (11.192%), and Coleoptera (8.290%) were the most dominant Orders on the campus, comprising 75.233% of the total, whereas the least abundant was Mantodea (0.622%). The South Campus exhibited high species diversity (Margalef index = 8.422), abundance (n = 686), Evenness (E = 0.776), and Shannon diversity (H = 3.124) of insects. It also showed a higher Simpson index (λ = 0.109) compared to the North Campus, which indicated (λ = 0.0610). Moreover, the South Campus recorded a very high number of species, with 56 species (Margalef index = 8.422) compared to 45 species (Margalef index = 7.813) recorded from the North Campus. The higher the index value, the greater the species richness. The high diversity and richness of insects in the southern habitat may be attributed to the large and less disturbed area, the presence of well-distributed ecological niches, more microhabitats, and an abundance of food. Therefore, understanding the factors that influence insect species diversity and abundance at the University of Kerala is important for conservation. This study, thus, highlights the diversity and abundance of insects and the need for sustainable measures to be implemented to conserve these significant species.

A preliminary survey on litter insect’s diversity through pitfall trap in different ecosystems of south 24 Parganas district, West Bengal, India

The present paper documents/discuss the preliminary study on litter insect abundance and diversity of insect species in diversity through pitfall trap in different ecosystems of South 24 Parganas District conducted during November, 2021- March, 2022. A total of 905 insects from 8 orders, 25 families were recorded. This study shows that Hymenoptera (44%) was the most dominant order according to total number of individuals, followed by Coleoptera (26%), Diptera (17%), Hemiptera (5%), Collembola (4%), Orthoptera (2%), Isoptera (1%) and Dictyoptera (1%). The present study was also conducted to determine the abundance of insects species; species richness, dominance and evenness of insect fauna from different ecosystems. The Simpson’s Index diversity is highest in Guava Orchard (0.345) and lowest in Medicinal Plants’ Garden (0.281). The species richness, evenness and diversity of insects were calculated by Margalef’s Index, Pielou’s Index and Shannon-Wiener Index respectively.

Seasonal abundance of insects from a vineyard in southern Romania

A field experiment was undertaken in a vineyard in southern Romania to evaluate the insect species abundance in this temperate climate area, over a period of 24 consecutive weeks, starting from April 2<sup>nd</sup> to September 27<sup>th</sup>, 2019. A total number of 19 303 insects were collected. After their morphological analysis, 89 species of insects were identified (nine orders and 28 families), of which 52 came from beneficial fauna (six orders and 14 families, 1 316 individuals) and 37 came from pest fauna (six orders and 26 families, 17 987 individuals). The beneficial species richness of the Coleoptera and Hymenoptera orders were the best represented. The pest insects of the Coleoptera and Hemiptera orders registered a high number of families, while the Thripidae family had the highest number of individuals. The highest diversity of insect species was found in the middle of April, and the lowest was found in the middle of August. The Bray–Curtis analysis revealed the stability of the insect community in the studied grapevine growing area. Grouping insects based on their similarities revealed the highest similarity (91.05–97%) in the warmest periods (June–August) and the lowest similarity (33%) in the spring (April).

Spatiotemporal patterns of emergence phenology reveal complex species‐specific responses to temperature in aquatic insects

AbstractAimClimate change is broadly affecting phenology, but species‐specific phenological response to temperature is not well understood. In streams, insect emergence has important ecosystem‐level consequences because emergent adults link aquatic and terrestrial food webs. We quantified emergence timing and duration (within‐population synchronicity) of insects among streams along a spatiotemporal gradient of mean water temperature in a montane basin to assess the sensitivity of these phenological traits to heat accumulation from mid‐winter through spring emergence periods.LocationSix headwater streams in the Lookout Creek basin, H.J. Andrews Experimental Forest, Oregon, USA.MethodsWe collected emerging adults of four abundant insect species twice weekly throughout spring for 6 consecutive years. We fit Gaussian models to the empirical temporal distributions to characterize peak emergence timing (mean) and duration (days between 5th and 95th percentiles) for each species/stream/year combination. We then quantified relationships between degree‐day accumulation and phenological response.ResultsOnly one of the four species (a caddisfly) showed a simple response of earlier emergence timing in both warmer streams and years. One stonefly had lengthy emergence periods resulting in substantial phenological overlap between warmer and cooler streams/years. Interestingly, two species (a mayfly and a stonefly) responded strongly to temporal (interannual) temperature differences but minimally to spatial differences, indicating that emergence was nearly synchronous among streams, within years. These two species had among‐stream differences approaching 500 degree‐days from mid‐winter to peak emergence. Conversely, duration of emergence was more strongly associated with spatial than temporal differences, with longer duration in lower‐elevation (warmer) streams.Main conclusionsEmergence phenology has species‐specific responses to temperature likely driven by complex cues for diapause or quiescence periods during preceding life cycle stages. We hypothesize a trade‐off between complex phenological response that synchronizes emergence among heterogeneous sites and other traits such as adult longevity and dispersal capacity.

Diversity and Seasonal Dynamics of Arthropods in Okomu Forest Reserve

A field survey was conducted in Okomu Forest Reserve Edo State, to assess the diversity and seasonal dynamics of arthropod species in selected land use systems (Okomu national park, Okomu rubber plantation and Okomu oil palm plantation). Samplings of arthropods were carried out between February and September 2020, arthropods were collected by hand picking and sweep net in each sampled plots at 25 m x 25 m in the study area. Insects encountered were killed and preserved by chloroform. Arthropods samples were taken to the laboratory for oven dry and identification. A total of 382 arthropods spread across 15 orders, 34 families and 81 species were recorded. The most dominant orders were Hymenoptera (Ants) followed by Odonta (dragonfly) and Lepidoptera (butterfly and Moth) during dry season while highest abundance of orders were Spirostreptida (millepde) followed by Hymenoptera (Ants) and Araneae (spider) during rainy season. Okomu National Park has the highest (220) insect species abundance follow by Okomu Rubber Plantation (136) while the least was Okomu Oil Palm Plantation (72) in the study area. Study revealed that Okomu Rubber Plantation has no record of Scolopendromorphra (centipede) andHemiptera (bug) while in Okomu Oil Palm Plantation no record of Scolopendromorphra (centipede), lepidoptera (butterfly), also there were norecord of blattodea (crockroach) order of insect species in Okomu National Park. The highest species diversity and evenness was observed in Okomu National Park (H’ = 3.03 and E’= 0.83) follow by Okomu Oil Palm Plantation (H’=1.89 and E’=0.86) while Okomu Rubber Plantation was the least (H’ = 1.53 and E’= 0.60). ANOVA showed significant (P≤0.05) different on diversity and abundance between land use systems while there is nosignificant (P≥0.05) different seasons in the study area. Observation was made on seasonal variation of arthropods species in different land use systems and dominant species as bio-indicators in the study area.

Analysis of type insect in Javanese Edelweiss (Anaphalis javanica) at Tegal Bungbrun Papandayan Mountain

This research is raining to find out the insect species, diversity index, abundance value, evenness value, dominance index, and insect density value on Javanese Edelweiss (Anaphalis javanica) in Tegal Bungbrun, Mount Papandayan. In this study the method used was purposive sampling using quadratic and Pitfal-trap techniques. The results obtained as many as 13 species belonging to 10 families and 5 orders with a total number of individuals is 235. The calculation results obtained, namely the diversity index at Tegal Bungbrun, Mount Papandayan of 1.0216, including at a moderate level, the highest abundance of insect species among 13 species, namely Apis andreniformis species with a value of 0.1957 are at abundant levels. Evenness value is 0.9171 which means that the insect evenness is in a stable condition. Insect dominance value of 1.9969 included in low dominance, dominated by Apis andreniformis of 0.3915. A density value of 9.4 is included in the low density category.

Household Level Paddy Storage and Insect Infestation of Paddy, Maize and Mungbean in Anuradhapura District of Sri Lanka

The augmented losses occur during the storage of grains but details on such information is minimum under Sri Lankan conditions. Unawareness of relevant and updated information on these losses prevents the adoption of appropriate remedial measures for the protection of these stored grains. Therefore, the current study was conducted in Anuradhapura district of Sri Lanka to determine the types of household-level storage structures/places used, grain losses occurred in those structures/places and nature of insect infestation of stored paddy, maize and mungbean. A questionnaire survey was conducted throughout Anuradhapura district using farmer families. Four main structures/places used in grain storage in different divisional secretariats were identified. The storage structures/places used from the highest to lowest frequency were room inside house, kitchen, room outside the house and temporary hut. Sitophilus oryzae was the most abundant stored pest followed by Sitotroga cerealella, Tribolium castaneum and Rhyzopertha dominica. The structures/places of grain storage and abundance of insect species were different among divisional secretariats. This study discloses the structures/places of grain storage, their frequency of use as well as the main insect species responsible for grain losses in the Anuradhapura district of Sri Lanka.

Assemblage of Insects on Medicinal Plants: An Insight from ICIMOD Herbal Garden in Godavari of Lalitpur, Nepal

Present study was conducted within the herbal garden of International Centre for Integrated Mountain Development (ICIMOD) in Godawari of Kathmandu valley to explore the insect communities in medicinal plants. Five medicinal plants, viz. Rauvolfia serpentina (= Sarpagandha), Urtica dioca (= Sissnu), Zanthoxylum armatum (= Timur), Valeriana jatamansii (= Sungandhawal) and Mentha spicata (= Pudina) were selected for the study. Insects were randomly sampled during four seasons from September 2017 to June 2018 using different collecting techniques, like hand picking, pit-fall traps, net-sweeping and stem beating. A total of 869 insects individuals belonging to 42 different genera were collected and identified. It was found that the abundance of insects was high during spring season (299 insects comprising 35 % of collected species), followed by summer (255 insects comprising 29 % of collected species) and winter (219 insects comprising 25 % of collected species) seasons, and low during autumn season (96 insects comprising 11 % of collected species). It was further found that the abundance of insect species was temperature-dependent, but was independent of relative humidity. The maximum indicator species were present on M. spicata. Taxonomic distinctness (delta+) of insects was high on V. jatamansii, but low on U. dioca.

A Study on the Diversity and Relative Abundance of Insect Fauna in Wukari, Taraba State, Nigeria

A field survey was conducted in Wukari, Taraba State to assess the diversity and abundance of insect species in selected habitats (residential, open field made up of grassland and an agro ecosystem). Insects recovered were wet preserved in 70% ethanol except butterflies and moths. A total of 4,501 insects spread across 9 orders, 34 families and 77 species were recovered. The most dominant order was Coleoptera with a relative abundance of (44.41%) and, the least was Orthoptera (0.84%). The most dominant insect species are Heteronychus mossambicus (11.44%) followed by Termes sp. (7.77%) and, Goryphus sp. (7.71%). Chlaenius decipiens, Cheilomenes sulphurea, Copris sp., Cicindela sp., Pseudantheraea sp., Derobranchus geminatus, Glaurocara townsendi, Camponotus perrisi, and Gryllus bimaculatus were the rare species with relative abundance of 0.02%. Species richness is based on number of individual insects measured. The highest species diversity was observed in the order Coleoptera (Shannon H’ =2.547) while, Isoptera was the least (H’ = 0.00). However, the highest species evenness was observed in the order Isoptera (E’ = 1.00). Fisher-alpha (α) index of diversity shows that the agro ecosystem has the highest index of diversity (α = 14.24) while, the residential area had the least (α = 11.9). This study therefore, brings to the fore the diversity and abundance of insects in Wukari and underscores the need for a more intensive study and for sustainable actions to be taken in conserving beneficial rare species while, managing the abundant pestiferous ones.

Attraction of Parastethorus nigripes and other insect species to methyl salicylate and (Z)-3-hexenyl acetate dispensers in a citrus grove and vineyard in south-eastern Australia

Herbivore-induced plant volatiles (HIPVs) play an important role in tritrophic interactions, and have the potential to attract beneficial arthropods into crops to enhance biological control of target pests. We conducted field trials in citrus and grapes to evaluate the response of abundant insect species to two HIPVs, methyl salicylate (MeSa) and (Z)-3-hexenyl acetate. Micromus tasmaniae (Hemerobiidae) showed significant attraction to MeSa, but only in the vineyard trial. Parastethorus nigripes (Coccinellidae) was also attracted to MeSa in the vineyard, but in the second citrus trial the treatment response was just outside the nominal 5% significance level. In the first citrus trial where P. nigripes was not separated taxonomically from the closely related coccinellid Stethorus vagans, a combined analysis was undertaken and significant attraction of both coccinellid species to MeSa was also observed. There was also a significant positive combined response of P. nigripes and S. vagans to (Z)-3-hexenyl acetate in the first citrus trial. Other predatory insect species did not respond to MeSa or (Z)-3-hexenyl acetate. As compared with the vineyard trial, weaker attraction of some insect species in the citrus trials may reflect high levels of background odour in the citrus orchard that could have interfered with normal insect olfactory responses. Our results support previous studies demonstrating coccinellids in the tribe Stethorini are often strongly attracted to MeSa. Deploying MeSa dispensers in vulnerable crops could attract increased numbers of P. nigripes, enhancing the biological control of pest tetranychid mites in Australian horticultural systems and reducing or eliminating the need for miticide applications.

A Report on Insect Community and Their Habitat Association in Daying Ering Memorial Wildlife Sanctuary, Arunachal Pradesh

Daying Ering Memorial Wildlife Sanctuary located in East Siang district, Arunachal Pradesh is a river island formed by the river Siang and Sibia. It is the only kind of sanctuary in Arunachal Pradesh which is surrounded by water bodies and most of the land covered with thatch grasses. The primary objective of the present study was to collect preliminary data on the insect diversity in this sanctuary. For this, the data were collected in four habitats viz. grassland, woodland, river bank and Jeep ghat camp area during February 04–07, 2015. The findings were analysed using Shannon index, Simpson index, Buzas and Gibson’s evenness measure, Berger–Parker index and Fisher-alpha index. During the survey undertaken, 44 species of insects belonging to 10 orders and 25 families were documented. Lepidoptera represented by 9 species showed the highest species richness as per Shannon index followed by Coleoptera, Orthoptera, Hemiptera and Hymenoptera represented by 6, 15, 5 and 4 species respectively. However, Simpson’s diversity index calculated the highest species richness of Coleoptera followed by Lepidoptera, Orthoptera, Hemiptera and Hymenoptera. The maximum number of species inhabited in the grassland (22). Among the habitats studied, the highest species richness was found in woodland followed by riverbank, grassland and the camp area. Ceratosolen solmsi marchali was estimated as the most abundant insect species in camp area, Distoleon tetragrammicus and Schizodactylus monstrosus in riverbank, Globitermes globosus and Acrida bicolour in grassland and Mycalesis heri in woodland habitat. Though, it was a preliminary survey species like yellow winged grasshopper Gastrimargus musicus, sand dune cricket S. monstrosus and globoid nest termite G. globosus can be pictured as potential flagship insects in the sanctuary. Besides, it showed the variation of diversity in entomofauna among the habitats indicating habitat specific dependence of the insect assembly in the sanctuary.

Role of weather parameters on seasonal abundance of insects in a mangobased agroforestry in Bangladesh, with particular reference to mango hopper

Weekly sweeping was done by sweep net in order to collect insects to study the effect of weather parameters on the seasonal abundance of total insect species as well as mango hopper population in a mango-based agroforestry in Bangladesh during January to June 2013. The total insect species abundance was the highest during April to May, following the flushing of inflorescence and fruit set. At that time temperature and relative humidity were comparatively higher and there was rainfall. Mango hopper population was the highest in May and synchronized to fruit set. The abundance of total insect species and mango hopper population showed significant positive correlation with temperature, and relative humidity, while significant negative correlation with light intensity and non-significant positive correlation with rainfall. Multiple linear regression equation based on weather parameters revealed 59.2% and 61.7% role on population build up of total insect species and mango hopper, respectively. Temperature was found to be the most important effect which individually contributed 31.3% on population abundance of total insect species and 29.9% on mango hopper.Bangladesh J. Agril. Res. 42(2): 197-205, June 2017

Watch your step: insect mortality on hiking trails

Abstract Hiking may have a negative effect on vertebrates, but the impact on insects is unknown. Large‐scale hiking may lead to habitat degradation, the introduction of alien species and the killing of insects occurring in places visited by people. The aim of this study was to determine the influence of hiking on the mortality of insects. Randomly selected hiking trails in the western Carpathians (southern Poland) were surveyed and dead insects lying on the trails were collected. To compare the composition of ground‐dwelling insects killed on trails, insects from free‐living populations were sampled with ground pitfall traps. The species abundance of insects killed on trails and those caught in traps differed significantly. Apart from common species, rare and legally protected insects were also found on the trails. Trail mortality peaked in July along with increasing hiking activity. Body size did not affect mortality, at either the species or individual levels. Species mobility influenced mortality, with less mobile species being more vulnerable to trampling. Trampled insects remained on the ground for a maximum of 72 h, although 50% disappeared within 24 h. Our results indicate that trail‐killing is, to some degree, a random process and that hiking can influence insects by the elimination of individuals. Given the total length of hiking trails in Poland (76 400 km), and the significant human impact on natural areas resulting therefrom, hiking may be having a negative influence on insect populations.