Tabanid Flies (Diptera: Tabanidae) of the Northern Part of Gyeonggi Province, Republic of Korea

Tabanid flies were surveyed using New Jersey light traps and Mosquito Magnet® traps at US Army installations and training sites in the northern part of Gyeonggi Province, Republic of Korea. A total of 344 tabanid flies, comprising 14 species and 5 genera, were collected from June to August during 2003‐2004. Dominant species were Chrysops vanderwulpi (57.3%), Haematopota sinensis (29.1%), Haematopota koryoensis (4.4%) and Tabanus mandarinus (2.3%). Mosquito Magnet traps that generated CO₂through the combustion of propane gas were nearly 6 times more effective in collecting tabanid flies than New Jersey light traps. Based on Mosquito Magnet trap collections, peak populations occurred from mid‐June to early July.;     

Determining meteorological drivers of salt marsh mosquito peaks in tropical northern Australia

In northern Australia the northern salt marsh mosquito Aedes vigilax is a vector of Ross River virus and is an appreciable pest. A coastal wetland adjacent to Darwin's residential suburbs offers a favorable habitat for Ae. vigilax, and despite vigilant mosquito control efforts, peaks of Ae. vigilax occur in excess of 500/trap/night some months. To improve mosquito control for disease and nuisance biting to nearby residential areas, we sought to investigate meteorological drivers associated with these Ae. vigilax peaks. We fitted a cross‐sectional logistic regression model to weekly counts of female Ae. vigilax mosquitoes collected between July, 1998 and June, 2009 against variables, tide, rainfall, month, year, and larval control. Aedes vigilax peaks were associated with rainfall during the months September to November compared with January, when adjusted for larval control and tide. To maximize mosquito control efficiency, larval control should continue to be implemented after high tides and with increased emphasis on extensive larval hatches triggered by rainfall between September and November each year. This study reiterates the importance of monitoring and evaluating service delivery programs. Using statistical modelling, service providers can obtain solutions to operational problems using routinely collected data. These methods may be applicable in mosquito surveillance or control programs in other areas.     

Meteorological driven factors of population growth in brown planthopper,Nilaparvata lugens Stål (Hemiptera: Delphacidae), in rice paddies

Growth of brown planthopper (BPH) (Nilaparvata lugens Stål) in rice paddies is mainly driven by meteorological factors under similar management practices. By analyzing field investigation and meteorological data collected from 2008 to 2013 in Nanchang, China, we show that BPH population densities and monthly growth rates (BGR) changed greatly from May to October, and these changes were closely associated with meteorological factors. Stepwise regression and path analysis indicated average speed of winds (AW) in June and lowest temperature (LT) in July were the first factors entering analysis, which interpreted 46.20% and 31.90% of their influences on BGR. While highest temperature (HT) in August and average temperature (AT) in September were the most important factors affecting BGR, but their direct path coefficients were all smaller than their corresponding indirect path coefficients. In October, relative humidity (RH), AW and number of raining days (RD) had significant effects on BGR. According to the sum of each meteorological factor entering stepwise regression analysis sequences, we found AW had the utmost effect on BPH growth, followed by AT and RH, but LT and RD least. The work demonstrate dynamic meteorological factors driving BPH growth and outbreak in rice paddies, which would facilitate the development of durable approaches for forecasting and controlling this destructive rice pest.     

Reduction of mosquito communities using the mass trapping method

This study was conducted to demonstrate the effect of the mass trapping of mosquitoes as an eco-friendly physical control method. It was conducted at the Ansan Hwarang Auto Camping Site in Gyeonggi Province, Republic of Korea. The study period was approximately 1 month (from July 2 to July 30, 2018). Inner and outer traps were installed to control mosquitoes inside and outside the study area. The inner trap consisted of 5 digital mosquito monitoring system units placed inside the study area, whereas the outer trap included 26 MOSHOLE-PRO units installed at 30 m intervals outside the study area. Both the inner and outer traps used carbon dioxide as an attractant. Additionally, the outer traps were grouped close to each inner trap using distance analysis and designated as Sn (n, inner trap number). According to the study results, analysis of the daily mean temperature and daily mean precipitation from 2017 to 2019 showed that the meteorological data were statistically insignificant. During the mass trapping period, the outer traps had the highest mean number of mosquitoes in the S1 group, whereas the other groups exhibited statistically similar results. Analysis of the mean number of mosquitoes in the inner trap confirmed a mean reduction rate of 59.39% through mass trapping, and the results were statistically significant (P < 0.001). This study confirms the effectiveness of mass trapping in reducing mosquito communities and suggests the possibility of creating mosquito-free zones by targeting mosquitoes both inside and outside the study area.     

Dry-season Mosquito Breeding Associated with Irrigation in the Northeast Kimberley Region of Western Australia: Potential Impact on Mosquito-borne Disease Transmission

Recent Ross River virus activity prior to the onset of the wet season in the Kimberley region of Western Australia points to an increased dry season mosquito-borne disease risk at Kununurra, compared to other Kimberley towns. This study describes a preliminary investigation into the role of the Ord River Irrigation Area at Kununurra in mosquito production during the dry season. Specifically, the study sought to determine whether the irrigation area has provided the opportunity for year-round breeding of arbovirus vector mosquitoes. A 10-day adult and larval mosquito sampling survey, in August 2003, revealed that mosquito breeding was occurring during the driest month of the year at Kununurra, supporting the hypothesis that mosquitoes can breed year-round. Importantly, significantly larger numbers and percentage of adult Culex annulirostris, an important disease vector in Australia, were collected within the irrigation area (44.6% of total catch) compared to nearby reference (nonirrigated) breeding sites (9.8%) (mean difference 76.2 per trap per night; 95% CI 38.6, 113.7; P <0.001). Larval Cx. annulirostris were also collected at several sites within the irrigation area, whereas none were collected at reference sites. These results indicate that mosquito breeding associated with anthropogenic environmental changes may be responsible for an increased health risk at the end of the dry season. Mosquito management needs to be given a high priority to ensure this potential health risk is not further exacerbated. Several control strategies to reduce breeding of disease vector mosquitoes are identified, primarily focusing on modification of breeding habitats and alteration of irrigation protocols.     

The effect of weather on the concentration of pollen within sugar-beet seed crops

The concentration of pollen in the air within diploid open-pollinated sugar-beet seed crops at Broom's Barn Experimental Station increased between 05.00 and 09.00 G.M.T. as relative humidity became less than 90%, was greatest between 09.00 and 11.00, when relative humidity was c. 75%, and gradually decreased towards evening. The average pollen concentration during 24 h periods ranged from 170 to 12400/m³ being greatest on fine, windy, dry days after periods of cooler weather. Rain during the morning washed pollen out of the air and damaged developing anthers, but rain in the late afternoon following a sunny morning seemed hardly to affect the pollen catch, while rain at night sometimes caused an immediate temporary increase in pollen concentration. Most pollen was released between 27 June and 31 July in all years (1965-7); more in the first than in the second half of July. 1965 was cool and damp, 1967 warm and dry, 1966 warm and dry early, and cool and wet late. The total pollen catch in 1965 was 83% and in 1966 31% of that in 1967 but the percentage germination of seed harvested in the 3 years was similar. The total pollen catch on a trap 230 m east of the 1965 crop was c. 1% of the catch within the crop on days with gusty westerly winds and the catch on a trap c. 46 cm above the 1966 crop averaged 78.6% of that at the level of most flowers.     

In situ hatching of Artemia monica cysts in hypersaline Mono Lake,California

Two emergence trap designs were tested in Mono Lake, California, to measure in situ hatching of Artemia monica cysts on the lake bottom. One design incorporated a removable sample bottle; the other had a catch tube which was pumped from the surface. Both traps rested on the bottom and had a narrow gap between the collecting funnel and bottom flange to allow the chemical conditions within the trap to be similar to those outside. This gap was open during April and May but, because some animals entered from outside the area enclosed by the trap, the gap was covered with 400 µm or 800 µm screen during June and July. The two trap types without screens sampled a station in oxic water 7 m deep similarly in April and May 1985. Mean daily hatching rates from April to May 1985 ranged from 720 to 25 340 shrimp m^-2 day^-1. In contrast, mean daily hatching rates during the same period at a station in anoxic water 21 m deep were from 3 to 138 shrimp m^-2 day^-1. June and July hatching rates in the shallow station were lower than in the spring, usually less than 1000 shrimp m^-2 day^-1.     

Development of an exposure-free bednet trap for sampling Afrotropical malaria vectors

An exposure-free bednet trap (the 'Mbita trap') for sampling of Afrotropical malaria vectors was developed during preliminary studies of mosquito behaviour around human-occupied bednets. Its mosquito sampling efficiency was compared to the CDC miniature light-trap and human landing catches under semi-field conditions in a screen-walled greenhouse using laboratory-reared Anopheles gambiae Giles sensu stricto (Diptera: Culicidae). When compared in a competitive manner (side by side), the Mbita trap caught 4.1+/-0.5 times as many mosquitoes as the CDC light-trap, hung beside an occupied bednet (P < 0.000 1) and 43.2+/-10% the number caught by human landing catches (P < 0.0001). The ratio of Mbita trap catches to those of the CDC light trap increased with decreasing mosquito density. Mosquito density did not affect the ratio of Mbita trap to human-landing catches. In a non-competitive comparison (each method independent of the other), the Mbita trap caught 89.7+/-10% the number of mosquitoes caught by human landing catches (P < 0.0001) and 1.2+/-0.1 times more mosquitoes than the CDC light trap (P = 0.0008). Differences in Mbita trap performance relative to the human landing catch under noncompetitive vs. competitive conditions were explained by the rate at which each method captured mosquitoes. Such bednet traps do not expose people to potentially infectious mosquito bites and operate passively all night without the need for skilled personnel. This trap is specifically designed to catch host-seeking mosquitoes only and may be an effective, sensitive, user-friendly and economic alternative to existing methods for mosquito surveillance in Africa.     

The long-term trends and seasonal variation of the aeroallergen Alternaria in Derby, UK

Very little is known in the UK about long term trends of theAlternaria spore although it is known to trigger asthma. It hasrecently become apparent that Alternaria spore levels areincreasing in Derby and a detailed study of Alternaria wasundertaken to investigate the increase in numbers, seasonal variationand diurnal periodicity. The seasonal (June—October)Alternaria spore concentrations show a distinct upward trendand there is evidence of an earlier seasonal start and an increase inthe seasonal duration. There has been a dramatic rise in the number ofdays with an Alternaria spore count above 50 spores per cubicmetre, with the peak daily count usually occurring in August butoccasionally in late July or early September. August generally has thehighest monthly total and for 1991–1998 there was a positivecorrelation with monthly rainfall and average temperature. Day to dayspore levels show a positive correlation between Alternariaspore concentrations and maximum temperature but a slight negativecorrelation with daily rainfall. The peak time for spore capture is14.00–22.00, and more than half the daily Alternariacatch is caught between 18.00 and 24.00 hours. The upward trend inAlternaria spore concentrations may be responsible forincreasing levels of respiratory disease, especially during harvesttime.     

The biology of pygmy whitefish, Prosopium coulterii, in a closed sub-boreal lake: spatial distribution and diel movements

Using gillnets and trap nets, we examined the spatial distribution, diel movements, and environmental tolerances of pygmy whitefish, Prosopium coulterii, in a small boreal lake in north-central British Columbia. Most gillnets were set below the thermocline but we also fished a shore net in the littoral zone. During the ice-free season (May to November) there was a strong diel onshore–offshore movement: during the day pygmy whitefish were offshore and below the thermocline (water temperatures of 4–6°C) but at night they were inshore and above the thermocline (water temperatures of 12–18°C). This onshore–offshore movement occurred close to the bottom and, regardless of where they were caught, most fish were <4 m off the bottom. Oxygen concentrations in most of the hypolimnion dropped to <5.0 mg l⁻¹ in June and by late August to <1.0 mg l⁻¹; indicating pygmy whitefish can tolerate low oxygen conditions. The catch of pygmy whitefish in gillnets set below the thermocline was highly skewed: 53% of the nets were empty, 37% caught 18 or less fish, and 10% caught 70% of the total catch (742 fish). Trap nets produced similarly skewed results: most trap net sets caught no pygmy whitefish but one set caught over 2,000 individuals. Our catch data suggest that in Dina Lake #1 some pygmy whitefish aggregate.     

Gargoor trap fishery in Kuwait,catch rate and species composition

Kuwait's fisheries include shrimp trawlers, gill nets, intertidal stake nets, and demersal fish traps, known locally as gargoor. The gargoor fishery used to be the nation's most important in terms of value and landings volume, but declines in catch rates have reduced its ranking. This paper describes the status of the gargoor artisanal fishery. The main landings place was sampled for catch and effort, and fish length‐frequency data from May 2003 to December 2005. The catch rate, monthly average number of boats operating, and the number of gargoor cleared were estimated for dhow boats fishing in Kuwait's waters and international waters, and speed boats operating in Kuwait waters only. Over the duration of the study period, the speedboat catch rates were higher than those of dhow boats, i.e., 3.7 kg/trap‐pull vs. 2.6 and 2.5 kg/trap‐pull for dhows fishing in Kuwait's territorial waters and international waters, respectively. The grouper, Epinephelus coicodes, was the main species captured, contributing 19.3% and 17.8% to the dhow catch in Kuwait waters and international waters, respectively. The catch rates by dhow boats declined from an average of 4.7 kg/trap‐pull in 2003 to 2.7 kg/trap‐pull in 2005 representing a 41% decrease. If this decreasing catch rate trend continues, then fishing effort should be reduced to allow stock recovery. It is recommended that the number of gargoor fished in Kuwaiti waters should be limited and that several no‐fishing zones be established to ensure the minimum spawning stock biomass and preserve biodiversity for all fisheries.     

GIS支持下青海湖地区草地蝗虫发生与月均温的相关性

为有效地进行草地蝗虫发生的预测预报,必须摸清其生长和繁殖与地理环境特征的关系,在青海湖地区,气温是影响草地蝗虫发生的主要因素,在Arc/Info和ArcView地理信息系统的支持下,选择了环湖地区邻近的16个气象站点,采用综合方法,在小尺度上模拟该区所需月份的月均温,建立了空间分布式气温信息数据库,然后,把野外调查的蝗虫密度在空间数据与相对应的月均温空间数据进行叠加,计算并分析月均温与草地蝗虫发生的关系。结果表明,月均温对草地蝗虫发生的影响是和该区蝗虫优势种的生命史密切相关的,即5、6月（孵化期）和7月（蝗蝻期）的月均温影响当年草地蝗虫发生;8、9月（交尾、产卵期）的月均温则影响次年草地蝗虫的发生,为该区草地蝗虫发生预报模型的建立提供依据。     

The association between meteorological variables and the abundance of Aedes taeniorhynchus in the Florida Keys

The black salt marsh mosquito, Aedes taeniorhynchus, is a serious nuisance pest and a potential vector of a number of arboviruses. This study examined the effect of wind direction, wind speed, temperature, and time of year on the abundance of Ae. taeniorhynchus collected in CO₂‐baited light traps at 12 sites in the Florida Keys during 2004. The dependent variable analyzed was the natural log of weekly mosquito abundance. The previous week's wind speed and wind direction, and the current week's temperature were used as independent variables. Simple and multiple linear regression models were used to assess the significance and nature of association between the meteorological variables and the natural log of mosquito abundance, and to determine whether the meteorological variables had significant associations with mosquito abundance after also controlling for time of year. Week of year was treated as a circular independent variable in the regression models, using the sine and cosine of week in radians to model the periodic seasonal fluctuation in mosquito abundance. Mosquito abundance was significantly associated with all meteorological variables and with week of year. Individually, previous week's wind speed and wind direction, and current week's temperature were able to explain respectively 24.5%, 24.5%, and 52.1% of the variation in mosquito abundance observed over the year. Week of year had the strongest individual association with mosquito abundance, explaining 65.7% of the variation in mosquito abundance. The meteorological variables were still significantly associated with mosquito abundance, after controlling for week of year. Week and the meteorological variables together explained 79.2% of the variation in mosquito abundance. The regression models fit to the data from this study suggest a strong periodic seasonal variation in mosquito abundance, with meteorological conditions explaining a significant portion of the variation beyond the seasonal trend.     

Population density ofMonochamus alternatus adults (Coleoptera: Cerambycidae) and incidence of pine wilt disease caused byBursaphelenchus xylophilus (Nematoda: Aphelenchoididae)

Summary The seasonal occurrence ofMonochamus alternatus and newly weakened trees were investigated in aPinus thunbergii stand for 4 years. Adult beetles were present between June and September with a peak in their population occurring in early July followed by a decline then a period of about one month being in a steady number. The average number ofBursaphelenchus xylophilus (Nematoda), which is the causal agent of pine wilt disease, within beetles decreased as the season advanced. Pine trees newly weakened byB. xylophilus appeared between June and October, especially from August to October. The proportion of weakened or killed trees was directly proportional to the average beetle density per tree from June to August.     

1961—2019年辽宁省高温天气变化特征

深入理解高温热浪天气的变化特征、辨识其影响因素,对于科学防控高温天气的危害、保障经济社会可持续发展具有重要意义。本研究基于1961—2019年6—8月辽宁省23个气象站点的日最高气温、相对湿度和风速数据,分析日最高气温(Tx)、日最高体感温度(AT)和高温热浪(连续3 d≥35 ℃)的变化特征,并采用灰色关联度分析气象因子对AT的影响。结果表明: 1961—2019年,辽宁省各站点6、7和8月Tx的平均值分别为26.19、28.29和28.14 ℃,气候倾向率平均值分别为0.17、0.20、0.17 ℃·(10 a)^-1,AT的平均值分别为27.35、31.13、31.08 ℃,气候倾向率平均值分别为0.38、0.35、0.28 ℃·(10 a)^-1。6—8月,研究区各站点Tx、AT与其气候倾向率均呈显著负相关关系,说明夏季Tx、AT低值区的增温幅度大于高值区,应重视研究区夏季Tx、AT低值区的高温防御。6—8月,各站点日最高气温≥35 ℃日数平均值为0.85 d·a^-1,6、7月明显大于8月,高值区主要位于辽宁西部,低值区主要位于辽宁南部和滨海地区,平均增加速率为0.20 d·(10 a)^-1。各站点多年平均高温热浪次数为0.071次,高值区主要分布在西部地区,南部和滨海地区未出现高温热浪事件。关联度分析表明,6月最高体感温度与相对湿度关系最密切,而7月和8月最高体感温度与最高气温关系最密切。因此,在高温天气预报预警中应充分考虑相对湿度的影响。     

Quantitative assessment of reproductive effort of the Manila clam Ruditapes philippinarum in a lagoon on Jeju Island (Korea) using enzyme-linked immunosorbent assay

We investigated gonad development and reproductive effort (RE) of the Manila clam Ruditapes philippinarum at Jeju Island, Korea. Gonad maturation and RE were determined using histology and an indirect enzyme-linked immunosorbent assay (ELISA). In June 2006, most of the clams (80%) in the lagoon were in the resting stage. Spawning clams first appeared in late July, and most clams spawned from early August to mid-September. The condition index increased gradually from early July to late August, then declined from early to mid-September, suggesting that spawning occurred during this period. The gonadosomatic index assessed by ELISA also increased dramatically from June (0.9), peaked in early August (19.7) then declined from late August to mid-September, indicating that clams at the study site had only one spawning pulse during the spawning period. Spawning at Jeju Island was one month later than Manila clams on the west coast of Korea. The delayed spawning and low RE of the clams could be in part, be explained by lower food availability, as the level of chlorophyll-a recorded in this study was much lower than that found in water from the west and south coast.     

Airborne pollen and spores on the Arctic island of Jan Mayen

A survey of airspora collected on Jan Mayen, an isolated North Atlantic island (71°N, 8°30′W), using a Burkard seven-day volumetric trap from 24th April to 31th August, 1988, revealed only very small concentrations. A total of 10 different pollen types were recorded, constituting a seasonal sum of 29 pollen grains. The local pollen season was confined to July, with Oxyria digna and Salix as the most numerous pollen types recorded. Exotic pollen grains, namely Betula, Pinus and Castanea type, were recorded in three periods during June and July. Studies of back trajectories indicate North America and/or Iceland and Greenland as possible source areas for the Betula pollen. There were more diatoms than pollen in the local airspora. Fungal spores mainly occurred in late July and August. Cladosporium constituted less than 5% of the total seasonal sum of fungal spores, while basidiospores contributed nearly 12%. The highest diurnal average of Cladosporium was 27 spores m^?3 air. The seasonal maximum of unidentified fungal spores reached a diurnal average of 639 spores m^?1 air on 27th August.     

川西亚高山不同年龄紫果云杉径向生长对气候因子的响应

运用树木年轮气候学的基本方法,建立王朗自然保护区紫果云杉在集中分布上限区域的年轮宽度年表,选取差值年表分析不同年龄云杉的径向生长同逐月气候因子的相关及响应关系,结果显示:幼龄组云杉年表的敏感度高于中龄组和老龄组云杉,幼龄组云杉对生长季前及生长季的气温状况显著正相关;中龄组云杉年表仅与当年4月份和7月份的月平均最低气温显著正相关;老龄组云杉的年轮宽度指数同上年生长季(上年8月份)的月平均气温和月平均最低温显著负相关,上年生长季高温的"滞后效应"在老龄组云杉体现的更为突出;幼龄组与中龄组云杉对当年6月份降水持续增加显示出明显的负相关关系,上年12月份的降水会对幼龄组和老龄组云杉径向生长不利。研究表明幼龄组云杉包含的气候信息要优于中龄组和老龄组云杉,在该区域进行相关研究时应根据研究需要选取不同年龄跨度的云杉年表。     

Effects of impounding coastal salt marsh for mosquito control on microcrustacean populations

Populations of microcrustaceans were studied for 24 months in two New Jersey high salt marsh impoundments, and in three separate 14 month studies of high salt marsh pools in northeastern Massachusetts.In Massachusetts high marsh pools, dominants were all harpacticoids: Amphiascus pallidus, Cletocamptus deitersi, Harpacticus chelifer, Mesochra lilljeborgii, Metis jousseaumei, and Nitokra lacustris. The cyclopoids Apocyclops spartinus, Halicyclops sp. and the calanoid Eurytemora affinis were also numerically important. While there was extensive overlap, dominants varied to some extent from year to year and among the three studies. The New Jersey saline impoundment fauna showed extreme dominance (low equitability) in the first summer, somewhat less in the second and much less in the third. Total microcrustacean densities also declined each year. Variation in Apocyclops spartinus densities was the major factor, as this species comprised in three consecutive summers, 95, 85 and 51% of the total zooplankton at one station. Diversity as species richness was highest in a New Jersey freshwater impoundment which compared well with South Carolina salt marsh values. Impoundment diversity which was very low, and comparable with that found in a New Jersey Spartina patens marsh, increased each year becoming progressively more like that found in the Massachusetts pools.Vegetation changed significantly in the New Jersey impoundments over the three years. Spartina patens died-off in the first summer, while S. alterniflora gradually declined each year. A visit to the site twenty years later showed all emergent vegetation to be gone. These successional zooplankton and vegetation changes, together with the possible consequences of interrupted marsh-bay exchanges should be considered before undertaking any coastal mosquito control involving permanent flooding.     

Crouching Tiger,Hidden Trouble: Urban Sources of Aedes albopictus (Diptera: Culicidae) Refractory to Source-Reduction

Our ultimate objective is to design cost-effective control strategies for Aedes albopictus, the Asian tiger mosquito, an important urban nuisance and disease vector that expanded worldwide during the last 40 years.  We conducted mosquito larval surveys from May through October 2009 in the City of Trenton, New Jersey, USA, while performing intensive monthly source-reduction campaigns that involved removing, emptying, or treating all accessible containers with larvicides and pupicides. We examined patterns of occurrence of Ae. albopictus and Culex pipiens, another urban mosquito, among different container types by comparing observed and expected number of positive containers of each type. Expected use was based on the relative frequency of each container type in the environment. Aedes albopictus larvae and pupae were found significantly more often than expected in medium volumes of water in buckets and plant saucers but were rarely collected in small volumes of water found in trash items such as discarded cups and cans. They were also absent from large volumes of water such as in abandoned swimming pools and catch basins, although we consistently collected Cx. pipiens from those habitats. The frequency of Ae. albopictus in tires indicated rapid and extensive use of these ubiquitous urban containers. Standard larval-based indices did not correlate with adult catches in BG-Sentinel traps, but when based only on Ae. albopictus key containers (buckets, plant saucers, equipment with pockets of water, and tires) they did. Although we found that only 1.2% of the 20,039 water-holding containers examined contained immature Ae. albopictus (5.3% if only key containers were counted), adult populations were still above nuisance action thresholds six times during the 2009 mosquito season. We conclude that in urban New Jersey, effective source reduction for Ae. albopictus control will require scrupulous and repeated cleaning or treatment of everyday use containers and extensive homeowner collaboration.