Pest Removal Research Articles

Apicultural Knowledge for Ecological Sustainability, Food Security and Economic Empowerment: A Case of Kajiado County, Kenya

Kajiado County, located in Kenya, faces interconnected challenges of ecological sustainability, food security, and economic empowerment. Amidst these challenges, beekeeping has emerged as a promising solution with the potential to address these multifaceted issues. This study examined the apiculture knowledge in Kajiado County, Kenya, for ecological sustainability, food security, and economic empowerment. The research utilized a mixed-method approach to collect data from beekeepers. The data collection methods used were observations, interviews, and focus group discussions. Data was analyzed using summary statistics and presented in the form of percentages and descriptions. The study revealed that the main motivation for beekeeping for all farmers was honey production while 30% kept bees for cultural practices and medicinal purposes. Beekeepers faced a myriad of challenges which ranged from negative attitudes towards beekeeping by young people at 10% to dry climatic conditions at 100%. Other major challenges included swarming of bees at 75% and attacks by pests and rodents at 83%. These problems were solved by providing water to the bees which was practiced by 100% of the beekeepers, removal of pests manually at 75%, and use of special indigenous trees to make hives with cooler temperatures. As an alternative source of livelihood in the ASALs being championed by the County governments since it is less affected by the adverse effects of climate change, the uptake of apicultural practices is still low in Kajiado largely due to a strong attachment to pastoralism. The apicultural practices in Kajiado County are largely small-scale and traditional with insignificant modernization. However, its practice has led to the management and conservation of some shrubs and trees, hence biodiversity conservation. The study recommends that traditional beekeepers be supported through the provision of relevant knowledge of beekeeping and modern equipment in order to increase both the quantity and quality of honey production for enhanced food security, economic empowerment and ecological sustainability.

The importance of shrubland and local agroecological practices for pumpkin production in sub-Saharan smallholdings

Land-use and local field management affect pollinators, pest damage and ultimately crop yields. Agroecology is implemented as a sustainable alternative to conventional agricultural practices, but little is known about its potential for pollination and pest management. Sub-Saharan Africa is underrepresented in studies investigating the relative importance of pests and pollinators for crop productivity and how this might be influenced by surrounding landscapes or agroecological practices. In Malawi, we selected 24 smallholder farms differing in landscape-scale shrubland cover, implementation of manual pest removal as an indicator of an agroecological pest management practice, and the number of agroecological soil practices employed at the household level, such as mulching, intercropping and soil conservation tillage. We established pumpkin plots and assessed the abundance and richness of flower visitors and damage of flowers (florivory) caused by pest herbivores on flowers. Using a full-factorial hand pollination and exclusion experiment on each plot, we investigated the relative contribution of pollination and florivory to pumpkin yield. Increasing shrubland cover decreased honeybee abundance but increased the abundance and richness of non-honeybee visitors. Manual removal of herbivores considered to be pests reduced flower visitors, whereas more agroecological soil management practices increased flower visitors. Neither shrubland cover nor agroecological management affected florivory. Pollinator limitation, but not florivory, constrained pumpkin fruit set, and increasing visitor richness decreased the relative differences between hand- and animal-pollinated flowers. We recommend improved protection of shrubland habitats and increasing agroecological soil practices to promote pollinator richness on smallholder farms.

Impact of red flour beetle infestations in wheat flour and their effects on dough and bread physical, chemical, and color properties

The impact of Tribolium castaneum on the quality and technological suitability of bread-making wheat flour was evaluated. The aim of this study is to investigate whether insect-infested flours can be used, after pest removal, avoiding the common use of insecticides and flour waste. The tests were carried out with wheat flour infested red flour beetle with 500 adults/kg (N1), 1000 adults/kg (N2) and 2000 adults/kg (N3), for two weeks. Flour color, total starch, protein and water contents, mineral composition and flour acidity were studied. The technological properties of the respective doughs and of bread were characterized. The results showed that infested flours acidity was significantly higher (N1, N2 and N3 = 0.3 g H2SO4/100 g) than the control (0.1 g H2SO4/100 g), the total starch content decrease, from 78 g (control) to 70 g/100 g dm (N3), and protein content did not significantly change, 7 g/100 g (control) to 8 g/100 g (N2); flour infested showed darker greyish tone which colour differences ΔE higher than 5, while the bread crust was lighter; the gelatinization properties of starch were slightly influenced by degree of infestation with gelatinization temperature reduction of about 5°c. There was not impact on the structure of the doughs from infested flours measured by rheology. The extensibility of the doughs, before and after fermentation, was moderately affected by the insects. For the respective breads, they kept their softness for longer, without significant volume change. These results encourage insect tolerance on grains and derivatives, avoiding chemical toxic insecticides and food waste. This pretends to be a contribution to pest management and decision support systems, prevention, and control of losses, relevant subject to stored products.

'Tidy' and 'messy' management alters natural enemy communities and pest control in urban agroecosystems.

Agroecosystem management influences ecological interactions that underpin ecosystem services. In human-centered systems, people’s values and preferences influence management decisions. For example, aesthetic preferences for ‘tidy’ agroecosystems may remove vegetation complexity with potential negative impacts on beneficial associated biodiversity and ecosystem function. This may produce trade-offs in aesthetic- versus production-based management for ecosystem service provision. Yet, it is unclear how such preferences influence the ecology of small-scale urban agroecosystems, where aesthetic preferences for ‘tidiness’ are prominent among some gardener demographics. We used urban community gardens as a model system to experimentally test how aesthetic preferences for a ‘tidy garden’ versus a ‘messy garden’ influence insect pests, natural enemies, and pest control services. We manipulated gardens by mimicking a popular ‘tidy’ management practice–woodchip mulching–on the one hand, and simulating ‘messy’ gardens by adding ‘weedy’ plants to pathways on the other hand. Then, we measured for differences in natural enemy biodiversity (abundance, richness, community composition), and sentinel pest removal as a result of the tidy/messy manipulation. In addition, we measured vegetation and ground cover features of the garden system as measures of practices already in place. The tidy/messy manipulation did not significantly alter natural enemy or herbivore abundance within garden plots. The manipulation did, however, produce different compositions of natural enemy communities before and after the manipulation. Furthermore, the manipulation did affect short term gains and losses in predation services: the messy manipulation immediately lowered aphid pest removal compared to the tidy manipulation, while mulch already present in the system lowered Lepidoptera egg removal. Aesthetic preferences for ‘tidy’ green spaces often dominate urban landscapes. Yet, in urban food production systems, such aesthetic values and management preferences may create a fundamental tension in the provision of ecosystem services that support sustainable urban agriculture. Though human preferences may be hard to change, we suggest that gardeners allow some ‘messiness’ in their garden plots as a “lazy gardener” approach may promote particular natural enemy assemblages and may have no downsides to natural predation services.

Facultative cleaning of spiral-horned antelope by the African paradise flycatcher (Terpsiphone viridis).

In cleaning associations, individuals known as “cleaners” remove and feed on parasites and pests found on, or around, other animals known as “clients.” While best documented in marine environments and as mutualisms, cleaning associations are widespread in terrestrial systems and range along a spectrum of obligate to facultative associations. In African savannas, cleaning associations primarily comprise facultative interactions between mammals and birds that remove attached parasites. Few reports, however, exist on cleaning associations that involve the removal of unattached pests. In this short note, I report a novel facultative bird–ungulate cleaning association involving the removal of unattached pests, between the African paradise flycatcher (Terpsiphone viridis) and two species of spiral‐horned antelope (Tragelaphus spp.): greater kudu (Tragelaphus strepsiceros) and Cape bushbuck (Tragelaphus sylvaticus). On multiple occasions, I observed African paradise flycatchers hawking flying insects around greater kudu and a Cape bushbuck during the dry season at the Mpala Research Centre in Laikipia, Kenya. These observations document a rare feeding strategy for the African paradise flycatcher and are among the few records on cleaning interactions involving the removal of unattached pests.

Development of an efficiency criterion for the removal of pest organisms (ulvoid green algae and diatoms) from Neopyropia aquaculture using the acid wash (pH shock) method

In Neopyropia aquaculture, pest organisms such as diatoms and ulvoid green algae lower the production yield, and acid wash (or pH shock) method is the most efficient method to overcome this problem. Here, we aimed to develop a removal efficiency criterion and quick reference for using acid activators to improve pest removal efficiency without damaging Neopyropia thallus. The maximum quantum yield (Fv/Fm) was measured using chlorophyll fluorescence. N. yezoensis was used as the cultivar, and Ulva linza and Navicula sp. were used as pest algae. In the acute HCl exposure experiment, N. yezoensis did not recover after 1 day when Fv/Fm decreased below 0.183. However, U. linza and Navicula sp. lost their photosynthetic ability when exposed for 20 s to 4% and 8% HCl, respectively, while the Fv/Fm of N. yezoensis was unaffected. Together, in the range of an acid concentration in which the Fv/Fm of Neopyropia thallus does not decrease below 0.2, a removal efficiency criterion for the pest organisms could be proposed, with minimum damage to the cultivated Neopyropia species.

Public willingness to engage in backyard conservation in New Zealand: Exploring motivations and barriers for participation

Abstract Citizen science and participatory conservation offer benefits to urban wildlife and help foster human–nature relationships in cities. To optimize conservation and social outcomes it is important that initiatives appeal to participants of a wide range of sociodemographic backgrounds. However, this can be challenging when motivation and willingness to undertake activities are influenced by socioecological context. In New Zealand, where control of invasive mammalian predators is a predominant strategy for conservation, trapping of rodents and mustelids has become a popular form of backyard conservation. To understand how the appeal of pest trapping compares with that of other conservation activities, we investigated relationships between sociodemographic characteristics of participants and willingness to undertake three different backyard conservation activities (trapping of pest mammals, monitoring of pest mammals and monitoring of native animals). We also examined barriers and motivations for participating in these activities. Willingness to engage in pest trapping was generally higher than that of the other activities, and although willingness scores for all activities were related to respondents’ connection to nature, this relationship was weaker for pest trapping than for monitoring activities. Willingness was also positively related to nature dose for all three activities. Concern for the environment was the only significant motivator of participation for all three activities while social interaction, contributing to community and enhancing one's ego were positively related to willingness for the monitoring activities only. The more general appeal of pest trapping may reflect its more tangible outcomes for conservation or the additional benefits it offers participants through removal of domestic pests. Understanding why some activities appeal across a wide sociodemographic spectrum may allow improved project design that maximizes participant recruitment. By encouraging participation of a wide range of people, such activities could provide an opportunity for people to become more connected with nature.

Awake by Mags DeRoma

Reviewed by: Awake by Mags DeRoma Elizabeth Bush DeRoma, Mags Awake; written and illus. by Mags DeRoma. Roaring Brook, 2021 [40p] Trade ed. ISBN 9781250753199 $18.99 Reviewed from digital galleys R 4-6 yrs Bedtime rituals from toothbrushing to book reading to goodnight snuggles are complete, and the narrator and her dog Oscar are ready to settle down. However, there’s a third set of eyes in the room, and there’s not going to be any sleep until the girl [End Page 53] evicts the unwelcome spider from her room. She concocts several outlandish plans for pest removal: sending it flying off on a paper airplane, lassoing it, launching it to the moon on a homemade rocket, or even, as Oscar suggests by pushing a book of nursery rhymes to her, washing it down the water spout outside her window. She settles on the time-honored method of trapping it under a glass and realizes the eight-legged creature isn’t nearly as scary as she thought; the closing scenes of an overturned glass, a spider nestled into its outdoor web, drowsy narrator and dog, and a blackout as the lamp clicks off assure viewers that everyone will sleep happily tonight. The plot is wispy, but the impossibility of nodding off with a creepy-crawly in the room strikes a virtually universal chord. It’s the artwork, though, that carries the story—“paint and soft pastels on a gazillion pieces of cut paper, all collaged together” convey the eeriness of the nighttime prowler that keeps getting bigger in the little girl’s imagination, while humorously spotlighting her inflated fear and planned overkill of the fragile little arachnid that just wants to get back to its web. An addendum demonstrates how to trap a spider with glass and cardboard, plus courage and a kind heart. Copyright © 2021 The Board of Trustees of the University of Illinois

Population recovery of alien black rats Rattus rattus: A test of reinvasion theory

AbstractReinvasion of pest animals after incomplete control is a major challenge for invasive species management, yet little is known about the behavioural and demographic categories of reinvaders or the mechanisms that drive population‐level responses to control. To understand the fine‐scale mechanisms of reinvasion, we examined changes in demography, movements and activity patterns of reinvading alien black rats Rattus rattus in the short (4 weeks) and longer term (3 months) following localised experimental pest removal. Using recovery and invasion theory, we tested three hypothesised mechanisms of reinvasion: the ‘in situ effect’, the ‘trickle effect’ and the ‘vacuum effect’. We created space for reinvasion by removing black rats from the core of replicate 1‐ha plots (short‐term experiment) and later by removing animals from the entire plot (longer‐term experiment). Reinvaders were characterised as dispersing juveniles, floaters or neighbours. Radio‐tracking quantified home range changes for adjacent resident animals (short‐term experiment only). In the short term, there was no net influx of rats after targeted removal. Radio‐tracked residents’ movements were highly variable and displayed no directional changes after nearby conspecifics were removed. However, in the longer term, removal led to slow population recovery through a mix of reinvading floaters, dispersing juveniles and shifting residents. These responses best support a hypothesis of reinvasion through a trickle effect, with rats being extremely mobile and having a high degree of population turnover, even in untreated sites. Our findings provide the first test of reinvasion theory at a small scale, demonstrating the importance of understanding the differing categories of reinvaders and mechanisms of reinvasion after population control. These mechanisms drive the rate of population recovery and, in turn, should help determine which strategy of pest control should be used, and the frequency with which they are implemented, in order to slow the recovery of pest populations.

Effectiveness of air-knives for pest removal from kiwifruit

Effectiveness of air-knives for pest removal from kiwifruit

Droplet Size Impact on Efficacy of a Dicamba-plus-Glyphosate Mixture

AbstractChemical weed control remains a widely used component of integrated weed management strategies because of its cost-effectiveness and rapid removal of crop pests. Additionally, dicamba-plus-glyphosate mixtures are a commonly recommended herbicide combination to combat herbicide resistance, specifically in recently commercially released dicamba-tolerant soybean and cotton. However, increased spray drift concerns and antagonistic interactions require that the application process be optimized to maximize biological efficacy while minimizing environmental contamination potential. Field research was conducted in 2016, 2017, and 2018 across three locations (Mississippi, Nebraska, and North Dakota) for a total of six site-years. The objectives were to characterize the efficacy of a range of droplet sizes [150 µm (Fine) to 900 µm (Ultra Coarse)] using a dicamba-plus-glyphosate mixture and to create novel weed management recommendations utilizing pulse-width modulation (PWM) sprayer technology. Results across pooled site-years indicated that a droplet size of 395 µm (Coarse) maximized weed mortality from a dicamba-plus-glyphosate mixture at 94 L ha–1. However, droplet size could be increased to 620 µm (Extremely Coarse) to maintain 90% of the maximum weed mortality while further mitigating particle drift potential. Although generalized droplet size recommendations could be created across site-years, optimum droplet sizes within each site-year varied considerably and may be dependent on weed species, geographic location, weather conditions, and herbicide resistance(s) present in the field. The precise, site-specific application of a dicamba-plus-glyphosate mixture using the results of this research will allow applicators to more effectively utilize PWM sprayers, reduce particle drift potential, maintain biological efficacy, and reduce the selection pressure for the evolution of herbicide-resistant weeds.

Vegetation connectivity increases ant activity and potential for ant‐provided biocontrol services in a tropical agroforest

AbstractIn natural and managed systems, connections between trees are important structural resources for arboreal ant communities with ecosystem‐level effects. However, ongoing agricultural intensification in agroforestry systems, which reduces shade trees and connectivity between trees and crop plants, may hinder ant recruitment rates to resources and pest control services provided by ants. We examined whether increasing connectivity between coffee plants and shade trees in coffee plantations increases ant activity and enhances biological control of the coffee berry borer, the most devastating insect pest of coffee. Further, we examined whether artificial connections buffer against the loss of vegetation connectivity in coffee plants located at larger distances from the nesting tree. We used string to connect Inga micheliana shade trees containing Azteca sericeasur ant nests to coffee plants to compare ant activity before and after placement of the strings, and measured borer removal by ants on coffee plants with and without strings. Ant activity significantly increased after the addition of strings on connected plants, but not on control plants. Borer removal by ants was also three times higher on connected plants after string placement. Greater distance from the nesting tree negatively influenced ant activity on control coffee plants, but not on connected plants, suggesting that connections between coffee plants and nest trees could potentially compensate for the negative effects that larger distances pose on ant activity. Our study shows that favoring connectivity at the local scale, by artificially adding connections, promotes ant activity and may increase pest removal in agroecosystems.Abstract in Spanish is available with online material.

TEKNOLOGI TERAPAN PENGHALAU BURUNG OTOMATIS BAGI PETANI PADI DI SALINGKA KAMPUS UNIVERSITAS ANDALAS

Sumatera Barat merupakan provinsi yang penduduknya rata-rata bekerja sebagai petani. Produksi padi di Sumatera Barat cukup tinggi, mencapai 55.532 ton per tahunnya. Namun, petani mengalami kesulitan dalam mengahadapi serangan hama, salah satunya yaitu hama burung. Hama burung menyebabkan kehilangan hasil mencapai 30% bahkan 100% pada tingkat serangan yang parah, dan pada tanaman serelia lainnya mampu memnyebabkan kehilangan hasil mencapai 67%. Akibat kehilangan hasil yang cukup tinggi, perlu dilakukannya pengendalian terhadap hama burung. Tetapi, pengendalian hama burung tidak sama dengan hama lain yang dapat dikendalikan secara praktis menggunakan pestisida karena hama burung yang bersifat mobile atau aktif bergerak. Saat ini petani masih menggunakan pengendalian secara mekanis yang di Sumatera disebut dengan istilah ‘Manggaro’. Dimana petani menunggui sawah dan ladangnya selama fase pengisian bulir hingga panen. Pengendalian seacara mekanis ini menghabiskan waktu petani untuk menghalau kedatangan hama burung.
 Berdasarkan permasalahan tersebut, maka dibutuhkan suatu usaha dan teknologi yang mampu digunakan untuk menghalau burung tanpa perlu diawasi oleh petani, hemat waktu dan lebih efisien dalam pengendalian serta dapat digunakan dalam jangka panjang. Kegiatan penelitian yang diusulkan meliputi pemasangan alat penghalau burung otomatis dengan sistem deteksi panas tubuh dan motor pengayun sumber bunyi di lahan sawah yang berada disalingka kampus Unand Limau Manis. Pengamatan yang dilakukan adalah hasil produksi padi terhadap 3 perlakuan yang diberikan yaitu penggunaan alat penghalau otomatis hama burung, penggunaan jaring burung dan lahan tanpa menggunakan alat atau dsebut juga sebagai kontrol. Selanjutnya,data yang diperoleh akan dianalisis untuk melihat efektivitas alat penghalau hama burung otomatis. Manfaat alat ini dapat membantu petani dalam pengendalian hama burung. Dimana petani tidak harus berada dilahan persawahannya seharian penuh untuk menghalau hama burung yang menyerang lahan persawahan tersebut.

Agroecological Pest Management in the City: Experiences from California and Chiapas

Urban gardens are a prominent part of agricultural systems, providing food security and access within cities; however, we still lack sufficient knowledge and general principles about how to manage pests in urban agroecosystems in distinct regions. We surveyed natural enemies (ladybeetles and parasitoids) and conducted sentinel pest removal experiments to explore local management factors and landscape characteristics that influence the provisioning of pest control services in California, USA, and Chiapas, Mexico. We worked in 29 gardens across the two locations. In each location, we collected data on garden vegetation, floral availability, ground cover management, and the percentage of natural, urban, and agricultural land cover in the surrounding landscape. We sampled ladybeetles, Chalcidoidea, and Ichneumonoidea parasitoids with sticky traps, and monitored the removal of three different pest species. Ladybeetle abundance did not differ between locations; abundance decreased with garden size and with tree cover and increased with herbaceous richness, floral abundance, and barren land cover. Chalcicoidea and Ichneumonoidea parasitoids were more abundant in Chiapas. Chalcicoidea abundance decreased with herbaceous richness and with urban cover. Ichneumonoidea abundance increased with mulch and bare ground cover, garden size, garden age, and with agriculture land cover but decreased with tree richness and urban cover. Predators removed between 15–100% of sentinel prey within 24 h but prey removal was greater in California. Generally, prey removal increased with vegetation diversity, floral abundance, mulch cover, and urban land cover, but declined with vegetation cover and bare ground. Although some factors had consistent effects on natural enemies and pest control in the two locations, many did not; thus, we still need more comparative work to further develop our understanding of general principles governing conservation biological control in urban settings.

High pressure air for pest removal from kiwifruit


 
 
 Insect removal from kiwifruit is important for improving access to overseas markets. Insect removal from kiwifruit by physical treatments such as high pressure washing is hugely successful but kiwifruit packing is carried out “dry”. Therefore, one potential option is the use of ‘air-knife’ blowers to remove insects. A system with air-knives from the sides and top that was mounted over a single-lane Compac grader was able to remove over 90% of artificially inoculated diapausing two-spotted mites (≈ 85/fruit). The difference in pest levels between untreated ‘Hayward’ kiwifruit fruit naturally infested with a wide range of insects (n=2194) and fruit exposed to air-knives (n=2204) was: mealybug 100%, beetle/weevils 91—100%, oribatid mites 93%, tuckerellid mites 98%, unidentified mites 88% , booklice 86%, thrips 74— 100%, Collembola 63%, cockroaches 100%, spiders 43%, scale insects 40%. Air-knives had no noticeable effect on ‘Hayward’ or ‘Zesy002’ (Gold3) fruit quality. These results indicate that air-knives using a high air-flow/low-pressure system can effectively remove high rates of “mobile” insects and first-instar scale insects, and can probably be implemented logistically and economically from a commercial perspective.
 
 

Wildlife detector dogs and camera traps: a comparison of techniques for detecting feral cats

ABSTRACTA major challenge in controlling overabundant wildlife is monitoring their populations, particularly as they decline to very low density. Camera traps and wildlife detector dogs are increasingly being used for this purpose. We compared the cost-effectiveness of these two approaches for detecting feral cats (Felis catus) on two pastoral properties in Hawke's Bay, North Island, New Zealand. One property was subject to intensive pest removal, while the other had no recent history of pest control. Camera traps and wildlife detector dogs detected cats at similar rates at both sites. The operating costs of each method were also comparable. We identify a number of advantages and disadvantages of each technique, and suggest priorities for further research.

Apple washers removal of insect pests and contaminants from export apples

Export markets require highquality fruit free from insects and mites of quarantine significance and with minimal or no agrichemical residues This presents a challenge for New Zealands pipfruit sector when developing novel pest management systems to meet these market requirements Brushbed apple washers are an important component of a systems approach to remove insects and mites in packhouses before fruit are exported A new apple washer using multinozzle rotors significantly reduced the incidence of insects and mites on apples Weathered residues of kaolin and hydrated lime were similarly reduced by this apple washer Assessment of fruit quality after apple washing and cool storage did not identify any commercially significant quality issues on the three apple cultivars examined Apple washer design to optimise pest removal from all locations on the fruit is discussed

Changes in physico-chemical properties of coffee due to hot air assisted microwave drying

Coffee is one of the most popular beverages in the world. One of the principle technological processes is drying; giving rise to the formation of the characteristic colour, flavour and taste of coffee brew. Conventionally there are two types of drying techniques used in the coffee processing, (sun drying and mechanical drying). The initial moisture content of harvested coffee is about 55-60 per cent and after drying lowers the moisture content to around 12 per cent (w.b). Drying should be uniform to obtain acceptable colour, size along with the removal of pests for a longer safe storage. Since coffee production is seasonal, traditional sun drying is quite tough. In recent years, microwave drying has gained popularity as an alternative drying method for a wide variety of food and agricultural products. With the fixed hot air temperature of 45°C, three different microwave output powers ranging from 0.5 to 1.5 kW and three different belt speed ranging from 5mm/s to 15mm/s were used in the drying experiments. Increasing the microwave output power resulted in a significant decrease in drying time within 5 per cent significance level. While the belt speed had no significant effect on the total drying time but had a significant effect on the physico-chemical properties.

Pest-removal services provided by birds on small organic farms in northern California

Many studies have established that birds may provide a pest removal service on farms, although few studies have taken place in temperate row crop agriculture. Wildlife-friendly agricultural practices such as organic farming and the use of hedgerows can in turn provide needed habitat for birds in developed landscapes. In this study, we examined how pest removal provided by birds varies within and between “wildlife-friendly” organic row-crop farms in northern California, USA. We used point counts to assess bird diversity on 29 small organic farms and simulated lepidopteran pest outbreaks on each farm using sentinel pest experiments. We measured how the probability of pest removal varied with local habitat characteristics within the farm, and with bird diversity parameters between farms. We also used exclosure experiments to determine whether birds provide a significant pest removal service in organic row-crop agriculture. In the sentinel pest experiments, birds depredated between 0 and 80% of caterpillar presentation stations within 7h, with a mean of 24% depredation per farm; the probability of pest removal was higher in areas close to uncultivated shrubby field margins (“hedgerows”). There was only weak evidence that the probability of pest removal was higher on farms with higher avian insectivore richness, and no evidence that pest removal varied with species diversity or abundance. Exclosure experiments on kale crops showed no significant effects of bird exclosure treatment on arthropod abundance or crop yield. However, natural caterpillar densities were relatively low during the exclosure experiment (approximately one caterpillar/m2). These results suggest that birds may be more helpful in responding to pest outbreaks than in controlling pests at non-irruptive densities on organic row crop farms in this study system. The prevention of pest outbreaks is an essential ecosystem service on any farm, and the rapid response of birds to pest outbreak conditions is an indicator of resiliency in the agroecosystem. Therefore, the retention of uncultivated shrubby field margins in this system may benefit both birds and farmers.

Forest bolsters bird abundance, pest control and coffee yield

Efforts to maximise crop yields are fuelling agricultural intensification, exacerbating the biodiversity crisis. Low-intensity agricultural practices, however, may not sacrifice yields if they support biodiversity-driven ecosystem services. We quantified the value native predators provide to farmers by consuming coffee's most damaging insect pest, the coffee berry borer beetle (Hypothenemus hampei). Our experiments in Costa Rica showed birds reduced infestation by ~ 50%, bats played a marginal role, and farmland forest cover increased pest removal. We identified borer-consuming bird species by assaying faeces for borer DNA and found higher borer-predator abundances on more forested plantations. Our coarse estimate is that forest patches doubled pest control over 230 km2 by providing habitat for ~ 55 000 borer-consuming birds. These pest-control services prevented US$75-US$310 ha-year(-1) in damage, a benefit per plantation on par with the average annual income of a Costa Rican citizen. Retaining forest and accounting for pest control demonstrates a win-win for biodiversity and coffee farmers.