Nest Diameter Research Articles

Bionomical observations of Small Carpenter Bee, Ceratina smaragdula Fibricius (Hymenoptera: Apidae)

The small carpenter bee, Ceratina smaragdula Fibricius is a non-Apis pollinator of many economically important crops. The nesting biology, nesting preferences, architects, foraging, hibernation, and mating behaviour of this solitary bee were examined in this study. Fifteen nests of C. smaragdula were collected and examined for the targeted attributes. C. smaragdula highly preferred (>80%) the area of field sides in Ravenna grass (Saccharum ravennae) for making their nests, at a preferred height of 82.74 cm from the soil surface. The nesting of C. smaragdula along roadsides and houses was 30-60% and <30%, respectively. C. smaragdula hibernated during early October to February, broke hibernation in the first week of March and initiated mating immediately. The main reproductive period was from March to August and the first generation emerged from late April to early May. The peak insect population was recorded from June to August. The mean nest length, nest diameter, and nest entrance diameter were 11.15 cm, 0.79 cm and 0.53 mm, respectively. This bee preferred a single gallery, having 3-5 cells per gallery. The gallery contents are eggs, larvae, pupae and adults. The generation development period was from 4-5 weeks and 3-4 generations per year were existed. C. smaragdula started foraging early in the morning (7.27 am) and ceased in the afternoon at (4.51 pm). The average time of foraging per flower was 21.67 seconds, and the bees returned to the nest after 7.48 min of their first forage. These findings could be helpful in designing artificial nesting required for the preservation of C. smaragdula.

The Breeding Ecology of the Painted Stork Mycteria leucocephala in Central Peninsular Malaysia

The Painted Stork (Mycteria leucocephala) populations in Putrajaya and Shah Alam, Peninsular Malaysia, have increased by almost 10%–13% every year. If this trend continues, it is believed that habitat overlap may occur between this species and the Milky Stork (Mycteria cinerea), which is currently threatened with extinction. Habitat overlap could lead them to compete for food and other necessary resources, and consequently, one species would outcompete another. However, little is known about the breeding ecology of the Painted Stork in Peninsular Malaysia. Therefore, this study aimed to evaluate the breeding ecology of the Painted Stork and examine its nesting characteristics and their effects on breeding success. Direct observations were made of colonies in the Upper Bisa Putrajaya Wetland (UBPW) and Tasik Shah Alam (TSA) during the breeding season from March to September 2016 and 2017. The peak of the breeding season was in June, and no differences were found in nesting colony parameters between study sites, including the nest diameter and nest building period, except for nest height. The average height above the ground level of TSA nests was higher than in UBPW. Human activities near the nesting site in Shah Alam may have led to the birds constructing nests higher to prevent disturbance and predation. Nest diameter and nest building period were influenced by the number of nestlings raised by parents. These findings provide new information that may be used in management programs to control Painted Stork populations and can be useful for conserving threatened species, particularly the Milky Stork.

Influence of breeding time, nest size, water depth, and egg size on the breeding success of the little bittern Ixobrychus minutus

Understanding the factors that influence avian reproductive output is critical for bird conservation as they reveal key considerations that directly impact a species’ long term survival and should be integrated into management plans. To better this understanding for the little bittern Ixobrychus minutus, we investigated how their breeding success relates to breeding time, nest size, water depth, and egg size in a man-made wetland (Ab-bandan) during the 2008 breeding season in Mazandaran Province, northern Iran. For each nest, the dates of the first egg laying, the first hatching, and the first fledging were recorded as well as clutch sizes. Nest size parameters (height, depth, and diameter), water depth under the nest, and egg characteristics (shape index and weight) were measured. The first egg was laid on March 21 and the last chick left the nest on June 24. From 140 eggs in 25 nests, 127 eggs hatched (91%) and 121 fledglings left their nests (87%). Generalized linear modeling revealed that nest diameter positively affected breeding success ( p = 0.001) meaning larger nests were more likely to produce fledglings. Further studies will be necessary to elucidate the underlying mechanisms.

Breeding Biology of Northern River Terrapin Batagur Baska in Captivity in Bangladesh

Northern River Terrapin, Batagur baska, is an ecologically extinct species in Bangladesh. The ‘Project Batagur’ has undertaken some important initiatives to resuscitate the nearly deceased population through captive breeding at Bhawal National Park, Gazipur, Bangladesh. We conducted a study on breeding biology of B. baska from May 2016 to June 2017 in the project site. Four adult females and three adult males comprised breeding pair in the study site. Male Batagur baska developed black colouration on head and neck, with rich crimson on dorsal portion of the neck during breeding season. During our study, we observed paired basking behaviour rather courtship and parental care. We found three nests from mid-March to first week of April. Females laid eggs at night and a total of 67 eggs were extracted from three nests; eggs were elliptical and whitish in colour. Clutch size varied from 18 to 28 eggs. There was significant positive correlation between clutch size and nest diameter (p = 0.03). The relationship was also positive and significant between egg weight and diameter (p = 0.01).The size of the egg was not related with the size of breeding females (r = 0.143).Average incubation period was (68.26 ± 5.23) days and there was significant negative relationship with temperature (p= 0.000), clutch size (p = 0.001), and hatching success (p = 0.004). Hatching success was also negatively co-related with temperature (p= 0.001). Hatching started in May and ended in the first week of June 2017 with mean hatching success of 91%. Simple linear regression showed positive relationship between egg length and hatchlings’ carapace length, plastron length, and height. We also found positive relationship between egg diameter and hatchlings weight, and carapace width. This study can be used as a protocol for captive breeding and rearing activities of threatened chelonians around the world. Dhaka Univ. J. Biol. Sci. 31(1): 67-78, 2022 (January)

Breeding phenology of Common Redstart (Phoenicurus phoenicurus) and its reproduction biology with artificial nests in Northeastern Ukraine

Abstract The paper describes investigations on the reproduction biology (nesting, clutching, hatching, fledglings` departure) of the Common Redstart (Phoenicurus phoenicurus) in artificial nest boxes (AN) in Northeastern Ukraine. There were three sites of research: Hetman NNP, NPP “Gomilshansky Forests”, and RLP “Feldman Ecopark”. The research was performed during the nesting period from the first week of April to the first week of July in 2015‒2020. Annually, 5‒8 bird counts were conducted at each site. The first complete egg clutches at Hetman NNP were observed from 08.05 to 17.05 (2015‒2020) and at NPP “Gomilshansky Forests” from 02.05 to28.05 (2017‒2020). Dates of the first egg laying, at various conditions, had inter-annual variability because of unstable weather conditions in May. The average parameters of nests in AN at Hetman NNP were the following: diameter of nests (D) ‒ 124.1±6.3 mm; diameter of trays (d) ‒ 61.5±1.7 mm; nest height (H) ‒ 63.5±9.4 mm; depth of trays (h) ‒ 48.6±2.7 mm; nest mass (m) ‒ 43.7±3.8 mm. The size of complete clutches in Northeastern Ukraine was calculated when eggs were incubated. According to the average indicators, during 2015‒2020, the average size of the clutch was 6.9±0.3 (5‒8) eggs at Hetman NNP, 6.2±0.4 (6‒8) eggs at NPP “Gomilshansky Forests” and 8.5±0.5 (8‒9) eggs at RLP “Feldman Ecopark”. Incubation period of Ph. phoenicurus lasted on average for 15‒20 days.

First description of the nest and juveniles of the Coppery Metaltail (Metallura theresiae), with comments on hummingbird nestling obesity

I provide the first description of the nest and juveniles of the Coppery Metaltail (Metallura theresiae), a hummingbird endemic to Peru. The locality of Unchog, in the elfin forest of the Carpish mountains in Huánuco, is where I found this species nesting. My descriptions are based on 4 nests found on different occasions (April 2013, January 2014, and Jul–Aug 2014). Coppery Metaltail used mainly moss, lichen, lycopodium, and twigs as materials to build their nests. I found 3 nest locations: a tree branch, creek banks, and an abandoned hut. The mean internal diameter of nests was 34.45 mm long by 42.52 mm wide (n = 4). I only measured the depth of 3 of them (mean = 33.83 mm). Metaltail eggs were white and had a mean of 12.93 by 8.3 mm (n = 2). Fledglings (n = 2) were observed in July and one of them reached up to 144% the mass of an adult. I comment on other cases of nestling obesity for different species of hummingbirds. The Coppery Metaltail selects different substrates for nesting and might reproduce throughout the year.

Nesting biology of two sympatric species of Megachile (Chrysosarus) (Megachilidae) in Argentina

Leaf cutter bees (genus Megachile) are a diverse group of pollinators of wild and cultivated plants. Many species nest in pre-existing cavities and use diverse building materials to construct their brood cells. For instance, species of subgenus Chrysosarus add a mud layer between two layers of leaves or petals. We studied similarities and differences in their nesting biology from 13 nests of Megachile (Chrysosarus) concava and 72 nests of Megachile (C.) diversa (Megachilidae) obtained in trap nests in northern Argentina. Females of M. concava used trap nests with higher diameters, shorter length, and built a lower number of brood cells per nest compared to females of M. diversa. In the latter species, the sex ratio was female-biased, but we observed male-biased progeny in shorter trap nests, thus the sex ratio of M. diversa could be context-dependent. Reproductive success was different between species: 40.5% for M. concava and 75.8% for M. diversa, desiccation and/or mold being the principal factor of mortality of immature stages. The attack from parasitic species represented 10.8% for M. concava and only 1.2% for M. diversa. Megachile concava, based on observations of a few nests collected during autumn, could be a bivoltine species and oligolectic of Faboideae, while M. diversa is a partially bivoltine or multivoltine, and polylectic species, with a marked turnover of pollen resource throughout its extensive reproductive season. Differences in the trophic niche and, to a lesser extent, in the inner diameter of trap nests used could allow their coexistence in the studied forests.

Effectiveness of Sea Turtle Conservation Management at the Turtle Conservation and Education Center of Serangan, Denpasar Bali

Turtles are one of the reptile animals that can migrate long distances along the Indian Ocean, Pacific Ocean and Southeast Asia. The purpose of turtle migration is to mate, find spawning locations and to find food. Sea turtles have an important role in maintaining the balance of the marine ecosystem. However, the high utilization of sea turtles by humans causes the turtle population to decline. One of the conservation sites that help the government program is in Serangan, Denpasar Bali, namely the TCEC (Turtle Conservation and Education Center), where there are several types of turtles such as the lekang turtle, hawksbill and green turtle. Data collection techniques in this study used observation methods including beach monitoring, relocation of turtle eggs to semi-natural hatchery hatching, hatchling and turtle nesting as well as measurement of turtle length and width carapase curve (CCL/CCW), sand temperature, nest depth, nest diameter, nest distance and nest calculation of the number of eggs to see the success of hatching. The results are turtle conservation activities, ranging from turtle maintenance, hatching of turtle eggs, relocation of eggs, and maintenance of hatchlings to release turtles. The effectiveness given by TCEC to manage and preserve the existence of sea turtles in Indonesia, especially in the Bali region is to provide awareness to the community by not consuming eggs and turtle meat.

Variation in common blackbird (Turdus merula) nest characteristics in urban and suburban localities in Crimea

Blackbird Turdus merula is a model species for studying the impact of environmental factors on the form and structure of nests. In the middle of XX, this species began to expand its range into the artificial forests of the Ukrainian steppe zone. This expansion may have led to changes in bird behaviour, including changes in nest construction choices (e.g., nest shape, size, location and building materials). In this study, we investigated Blackbird nest diversity (i.e, size, volume, and composition) in the park of Simferopol (a city in Crimea, South Ukraine) and in an artificial forest located nearby. We found a significant inverse relationship between nest placement height and external nest diameter. External nest depth was greater in the forest than in the park. This difference reflects the variation in plant life form between the sites. More specifically, nests in trees have significantly greater external depth than the nests located on shrubs. Most nests in both urban and suburban localities contained natural and anthropogenic materials; there was no significant difference in component types between sites. In general, the anthropogenic materials played a decorative role and also served as camouflage.

Assessing the impact of seasonality on Cross River Gorilla Nest Construction at Kagwene Gorilla Sanctuary, North-West Cameroon

The Cross River gorilla, one of the most endangered subspecies of western gorilla (Gorilla gorilla) is endemic to 12 to 14 sites at the Cameroon-Nigeria border, where it is facing enormous threats from habitat loss, bush meat trade and minor climate changes (seasonal changes). In a strive to reduce the enormous stressors on this subspecies, this study assesses the impact of seasonality on nest construction by Cross River gorillas in the Kagwene Gorilla Sanctuary with the objective of evaluating the impact of seasonal changes on the nest construction. To achieve this goal, the study employed a hunter guided survey team, as well as guides/trackers of the Wildlife Conservation Society. This team regularly tracks and searches the forest for gorilla signs using vegetation trails, food prints, dung, and feeding signs which are subsequently followed onwards to the nesting site. Data were collected from January to December 2014. A total of 268 fresh gorilla nest sites were observed containing 1813 individual nests. Out of the 1813 nests recorded, 39.6% (N=718) of the nests were on the ground and 60.4% (N=1095) on trees. The frequency of each nest type varied significantly among months (P =0.4433). There was a significant effect of season on nest category. Ground categories (bare earth, herbaceous, woody and mixed) were more common in the dry season (74.9%) than in the wet season (25.1%). On the other hand, tree nests were more common in the wet season (77.4%) than in the dry season (22.6%). Mean nest diameter for the two seasons (dry and wet) was 1.1 and 1.3 m, respectively. The mean nest height was 12.5 m for both seasons. Cross River gorillas showed higher preferences for tree nests within the height class interval of 11 to 15 m (49.6%). The distribution of nests across gradient of altitudes did not vary significantly between seasons (P>0.05), and nests were most common on steep slopes (n=810). Seasonality did not significantly affect the choice of slope (P>0.05). There was a significant difference in the habitat types (primary forest, light gap, secondary forest and rock) used for nesting, with primary forest being most preferred. Nest site distribution was predominant in the northern section of the sanctuary. This study reveals that, both temperature and rainfall play an important role in nest construction by Cross River gorilla at Kagwene. Key words: Cross River gorilla, nest, seasonality, Kagwene Gorilla Sanctuary.

Rozšíření a biologie jestřába lesního (Accipiter gentilis L.) v Chřibech

In 2002–2006, mapping the goshawk (Accipiter gentilis L.) population was carried out at the SE edge of the Chřiby Upland, the Czech Republic. At the same time, the food spectrum of the predator was determined in detail in 2004. The studied area amounted to about 30 km2. In the area, 5 nest localities occurred. Each year five occupied nests were observed. The food spectrum was analysed according to leftovers of food in nests and in the vicinity of the nests. In total, 387 leftovers of food were found. Birds represented 52%, mammals 42% and other animals (insect, reptiles etc.) 6% of prey. The population of goshawk was monitored from the period of a wedding flight to a period when young birds left their nest during the period of five years. The number of eggs was on average 2.9 per one nest. The total number of laid eggs was 73 during five years. The number of brood was on average 2.7 per one nest. Sex ratio was 47/53 per cent in favour of males. The total number of hatched birds was 68 during five years, out of the number 32 females and 36 males. Moreover, dimensions of nests at particular localities were also determined. The diameter of nests was on average 72.2 cm and the mean height of the actual nest was 48 cm. Nests occurred at an average height of 21.3 m.

Adaptive latitudinal variation in Common Blackbird Turdus merula nest characteristics

Nest construction is taxonomically widespread, yet our understanding of adaptive intraspecific variation in nest design remains poor. Nest characteristics are expected to vary adaptively in response to predictable variation in spring temperatures over large spatial scales, yet such variation in nest design remains largely overlooked, particularly amongst open-cup-nesting birds. Here, we systematically examined the effects of latitudinal variation in spring temperatures and precipitation on the morphology, volume, composition, and insulatory properties of open-cup-nesting Common Blackbirds’ Turdus merula nests to test the hypothesis that birds living in cooler environments at more northerly latitudes would build better insulated nests than conspecifics living in warmer environments at more southerly latitudes. As spring temperatures increased with decreasing latitude, the external diameter of nests decreased. However, as nest wall thickness also decreased, there was no variation in the diameter of the internal nest cups. Only the mass of dry grasses within nests decreased with warmer temperatures at lower latitudes. The insulatory properties of nests declined with warmer temperatures at lower latitudes and nests containing greater amounts of dry grasses had higher insulatory properties. The insulatory properties of nests decreased with warmer temperatures at lower latitudes, via changes in morphology (wall thickness) and composition (dry grasses). Meanwhile, spring precipitation did not vary with latitude, and none of the nest characteristics varied with spring precipitation. This suggests that Common Blackbirds nesting at higher latitudes were building nests with thicker walls in order to counteract the cooler temperatures. We have provided evidence that the nest construction behavior of open-cup-nesting birds systematically varies in response to large-scale spatial variation in spring temperatures.

Nesting ecology of the exotic Trachemys scripta elegans in an area of Southern Italy (Angitola Lake, Calabria)

The nesting ecology of the slider turtle Trachemys scripta elegans was studied in Angitola Lake, a natural protected area in Calabria (Southern Italy). During 2008-2010, data were collected based on 1081 egg shells from 250 nests. The average number of egg shells per nest was 4.3 (min-max = 1-16) and the clutch size increased from 2008 to 2010. Two main hatching periods were identified: one in July and another in September. There were significant correlations between nest diameter and nest depth, between nest diameter and egg shell number, and between nest depth and egg shell number.

Effects of nest characteristics and black rat Rattus rattus predation on daily survival rates of great egret Ardea alba nests in mangrove forest in the Hara Biosphere Reserve, the Persian Gulf

We estimated variations in breeding parameters and daily survival rates (DSR) of nests of the great egret Ardea alba during 2008‐2009 in the Hara Biosphere Reserve, the Persian Gulf. We modelled and compared nesting success using an information‐theoretic approach to assess effects of nest site and temporal covariates on DSR. The mean DSR was 0.9896 (95% CI: 0.9931‐0.9842) and the overall nest survival was 0.49 (0.35‐0.63). Distance to black rat Rattus rattus nest sites was the most important covariate (∑ωi = 0.96) affecting the survival of great egret nests whereas distance to other great egret and western reef heron Egretta gularis nests was less influential. Neither nest diameter nor nest age effectively explained variation in nesting success. We concluded that black rat predation is the most important factor affecting the breeding performance of great egrets in the Hara Biosphere Reserve, and control measures should be undertaken to reduce the negative effects of this invasive rodent on the heron colonies of mangrove forests in the Persian Gulf.

Golden eagle Aquila chrysaetos in Xinjiang: Nest-site selection in different reproductive areas

The reports about the geographical distribution, reproductive ecology and population dynamics of the golden eagle Aquila chrysaetos were mostly descriptive in China, and lack quantified studies for the nest-site selection of this species. We carried out our investigations by direct observations in the northern Xinjiang during 2004–2011, attempting to reveal the main factors that affected on the nest-site selection and the differences of ecological variables of reproductive areas in the species (Mts. Tian Shan spurs and Mt. Kalamaili). We measured 38 nests totally belonging to the 16 home ranges. The average number of nests in each home range was 2.38±0.41, and with no significant difference (P>0.05) between different reproductive areas. In all cases golden eagles nested on cliffs (n=38) in our study area. The average external diameter of nests was (198.4±8.2) cm × (159.3±14.2) cm (Mean±SE, n=9), and inner diameter was (91.1±4.4) cm. The nest-site selection was extremely significant difference (P<0.01) for the different reproductive areas, i.e. elevation, hill height, nest-site height, cliff height, gradient, the distance to water resource, and the distance to residential area. The distance from the cliff bottom and from the cliff top were significant difference (P<0.05). However, the slope position, nest position, distance to unpaved and paved road were not significant difference (P>0.05). In Mts. Tian Shan spurs, the elevation was obviously selective (χ2=13.99, df=4, P<0.01), and mainly nested in altitude of 1 932–2 197m, where the main aspects were SW (36.4%, n=22) or SE (31.8%), and the slope gradient was above 85°. In Mt. Kalamaili, also it was found the significant differences for elevations (χ2=11.44, df=3, P<0.01), the eagle mainly nested in altitude of 1 112–1 423m, with aspects of NW (68.8%, n=16), and the gradient was relatively flat. In reproductive areas, eagles nested in the mid-slope parts and higher slope position (92.1%, n=38). Eagles nested far from the seriously disturbed places by human, especially roads, residential area, mineral mines, etc. The principal component method of the factor analysis indicated that there were four main factors affecting on the nest-site selection by golden eagle in Mts. Tian Shan spurs: human disturbance factor (eigenvalue is 4.800, Ratio of contribution is 34.28%), nest position factor (3.002%, 21.44%), prey factor (2.601%, 18.58%), and terrain factor (1.305%, 9.32%). In Mt. Kalamaili, there are five main factors as following: terrain factor (eigenvalue is 5.110, Ratio of contribution is 34.07%), nest position factor (3.747%, 24.98%), human disturbance factor (2.123%, 14.16%), prey factor (1.584%, 10.56%), and gradient factor (1.111%, 7.41%). To conclude, human disturbance and landscape are the two main factors affecting on the nest-site selection of the eagle. The nest-site selection is a result of trade-off among the human disturbance, landscape and prey amount. Eagles take corresponding strategy of nest-site selection for adaptation to the various environments, having different conditions for the eagle reproductive. So, we recommended the improvement of the habitat fitness for the increasing of the reproductive success of the golden eagle.

Cocoon orientation in the nests of red mason bees (Osmia bicornis) is affected by cocoon size and available space

Proper orientation of cocoons in linearly structured nests can be crucial for the survival of hatching bees. Nevertheless, misoriented cocoons appear in nature in notable proportions. A detailed analysis of sex, space available for cocoon spinning, cocoon size, and nest diameter in the red mason bee (Osmia bicornis) showed that smaller males are more prone to misorientation than larger females. Generally, smaller individuals of both sexes are more often misoriented because smaller larvae disregard the direction of the entrance during cocoon construction. Moreover, cocoons in stems of smaller diameter are less often misoriented than bees in wider nests. Our results suggest that cocoon size and available space are the most important traits affecting cocoon orientation.

Undecomposed Twigs in the Leaf Litter as Nest-Building Resources for Ants (Hymenoptera: Formicidae) in Areas of the Atlantic Forest in the Southeastern Region of Brazil

In tropical forests, the leaf-litter stratum exhibits one of the greatest abundances of ant species. This diversity is associated with the variety of available locations for nest building. Ant nests can be found in various microhabitats, including tree trunks and fallen twigs in different stages of decomposition. In this study, we aimed to investigate undecomposed twigs as nest-building resources in the leaf litter of dense ombrophilous forest areas in the southeastern region of Brazil. Demographic data concerning the ant colonies, the physical characteristics of the nests, and the population and structural of the forest were observed. Collections were performed manually over four months in closed canopy locations that did not have trails or flooded areas. A total of 294 nests were collected, and 34 ant species were recorded.Pheidole,Camponotus, andHypoponerawere the richest genera observed; these genera were also among the most populous and exhibited the greatest abundance of nests. We found no association between population size and nest diameter. Only tree cover influenced the nest abundance and species richness. Our data indicate that undecomposed twigs may be part of the life cycle of many species and are important for maintaining ant diversity in the leaf litter.

The effect of vegetation and water depth on nest patterns of the Eurasian coot (Fulica atra)

Nest characteristics of the Eurasian coot (Fulica atra) and the effect of vegetation and water depth on nest size were investigated. The study was conducted in 2008 on Poyrazlar Lake (Sakarya) in northwest Turkey. Depth and distance from the edge has no effect on internal nest diameter; however, nest height and external diameter are correlated with water depth.

The effect of nest relocation on embryonic mortality and sex ratio of Loggerhead Turtles, Caretta caretta (Reptilia: Cheloniidae), at Dalyan Beach, Turkey

Marine turtles are globally endangered and one important conservation technique is nest relocation. This study assesses the relationship between nest site factors (wet nest depth, dry nest depth, total nest depth, nest diameter, distance to sea, moisture, clutch size and incubation duration) and embryonic mortality of natural and relocated nests at Dalyan beach, Turkey. Principal component analyses (PCA) revealed a three-factor structure for the natural nests and a four-factor structure for the relocated nests. The clutches in natural and relocated nests had a total of mortality ratio of 21% and 12%, incubation duration of 52 and 50 days, and estimated female ratio of 80% and 88%, respectively. Thus, mortality was lower and incubation faster in the relocated nests, but the proportion of females was higher. Hatching success in relocated nests (84.4%) was significantly higher than in natural nests (72.7%).

Use of Trap-Nests with a Neotropical Leaf-Cutter Bee Megachile (Moureapis) anthidioides (Hymenoptera: Megachilidae)

Bees of the genus Megachile Latreille are popularly known as leaf cutters, and females utilize leaves and petals for construction of their nest cells. Their cavity-nesting behavior probably developed from Megachile ancestors that nested in the ground (Eickwort et al., 1981). This genus is large, with around 1320 known species (Michener, 2000) of which 161 occur in Brazil (Silveira et al., 2002). Further information about these insects is sparse (Almeida et al., 1997). From November 2006 to February 2010 trap nests (made of cardboard tubes inside plastic bottles and black cardboard tubes inside wooden blocks) were placed horizontally on the ground along a boundary of a semi-deciduous secondary forest in a in Itacolomi State Park in the city of Ouro Preto, Minas Gerais, Brazil. Trap nests were uniform in length (120 mm) but varied in their inner diameters (6–12 mm). They were inspected twice a month for Megachile spp., and completed nests were removed to the laboratory for analysis. Fifty-seven nests of Megachile (Moureapis) anthidioides Radoszkowski were built in trap-nests not previously used by other species. The diameter of trap-nests that were occupied ranged from 6 to 12 mm (8.49 6 1.25; median 6 standard deviation). Nest diameter preferences vary from species to species; according to Aguiar and Martins (2002) the bees prefer diameters that best accommodate their bodies within the cells. A cavity of large diameter makes the bee expend more energy to fill the excess space with construction material. During the end of dry season (August and September of 2007) M. anthidiodes occupied almost 30% (n 5 16) of the trap-nests. This high nesting rate at the end of the dry season may be related to the availability of food that the females use to feed their offspring. The nest cells were built with leaves, and we found an average of 5.06 6 2.22 cells per nest. The construction of cells followed the pattern reported by Krombein (1967) for other species of Megachile that made 1 to 9 cells per nest. Of the 226 emerged adults, 144 were males and 82 females, resulting in a sex ratio of 1:0.56. The male/female difference was statistically significant (x 5 13.154; P , 0.05). In general, the adults emerged 4 to 8 weeks after the female closed the main entrance. There was parasitism in 14.28% (N 5 8) of the occupied trap-nests, and two parasitic species emerged from them: Coelioxys (Acrocoelioxys) sp., from three nests, and Melittobia sp., from one nest. The presence of parasitic bees of the genus Coelioxys in Megachile nests is widely known from literature. These bees are the principal parasites found in Megachile nests, but some species also parasitize nests of other solitary bees mentioned in literature on trap-nests (e.g., Aguiar and Martins, 2002; Alves-dos-Santos, 2003; Aguiar et al., 2005; Aguiar et al., 2006). This is the first record of M. anthidioides in trap nests. To date, there have only been reports of collecting this species (e.g., Silveira and Cure, 1993; Silveira et al., 1993; Silveira and Campos, 1995; Goncalves and Melo, 2005). The abundance of M. anthidioides in the trap-nests could indicate the scarcity of appropriate sites for nesting by this species in the study area, since that area has already suffered a substantial anthropogenic impact.