Landmark orientation during the approach to the nest in the stingless beeTrigona (Tetragonisca) angustula (Apidae,Meliponinae)

Summary We displaced a small nest box containing stingless bees (Trigona (Tetragonisca)angustula) over distances of up to 1.6 meters in different directions and counted the numbers of returning foragers to measure the effects of this manipulation on the homing ability of bees. Bees find it hard to locate the nest box when it was displaced more than about 1 m backwards, forwards or sideways relative to the direction into which the nest entrance pointed. They do not find the nest when its height above ground is changed. The bees use landmarks in the vicinity of the nest to locate it: When the nest box is displaced and landmark positions are changed so that their angular position at the new nest site is the same as at the normal nest position their homing ability is less impaired than it is without changes in landmark positions. Our results show that the bees do not use the nest box itself as a landmark until they have approached the nest position to within about 1 meter with the aid of surrounding landmarks.     

Ousting of the Common Redstart (Aves: Turdidae: Phoenicurus phoenicurus) from its nests by the bumblebee Bombus niveatus vorticosus (Hymenoptera: Apidae)

During a study of bird nesting in SW. Anatolia, 125 man-made nest boxes have been installed, 3 m high, in the trees. These nest boxes have been occupied by several bird species (Phoenicurus phoenicurus, Parus major, Parus ater, Sitta krueperi, Certhia brachydactyla). Of the 48 Redstart nests, 19 (40 %) had been successfully invaded by the bumblebee Bombus niveatus vorticosus. This invasion occurred at different times in the nest building cycle: - during the building of the nest, - during the incubation or - after the hatching of the young. Once installed in the nest of the Redstart, the bumblebee does not directly attack the bird, but disturbs it by continuously rearranging the nesting material and by covering the bird’s brood. Eventually, the bird deserts its nest and brood. The Redstart does not display any agonistic behaviour towards the bumblebee. Nests of other bird species are never invaded.     

沙漠石蜂的筑巢习性和行为

2004-2005年在西鄂尔多斯地区,选择巢室数＞300的沙漠石蜂Megachile(Chalicodoma)desertorum Morawitz巢区,通过标记巢室和雌蜂,在整个成蜂活动期连续对沙漠石蜂的筑巢习性和行为进行了观测研究.结果显示:该蜂一生一般能建8～12个巢室,优先利用未被破坏的旧巢.利用旧巢的过程为:...     

Effects of stimuli emanating from the nest on the reproductive cycle in the ring dove. III: building in the postlaying period and effects on the success of the cycle.

Nest-building as a functional activity is shown to continue well into the incubation period of the ring dove (Streptopelia risoria), its intensity depending on the state of the nest. The presence of a nest has profound consequences on breeding success: pairs with no nests did not incubate well and did not hatch their eggs. Pre-laying disruption of the nest or of the usual roles of the male and female had no effect on incubation as long as a nest was present when the eggs were laid. It is concluded that the presence of a nest is necessary for the proper establishment of incubation. The possible role of the nest in incubation is discussed.     

Nest architecture of the ant <Emphasis Type="Italic">Formica pallidefulva</Emphasis>: structure,costs and rules of excavation

Summary The architecture of underground ant nests was studied in the ant Formica pallidefulva. These ants build shallow (30–45 cm deep) nests, which consist of more or less vertical shafts that bear chambers. Shafts are modular units of nest growth; nests are enlarged by adding more shafts or extending previously existing ones. The nests are top-heavy, their volume declining exponentially with depth. The total volume of the nest is strongly correlated with the number of worker occupying the nest (R² = 0.87). Some of the rules and templates used by workers for nest construction were determined: (a) chambers are formed in the direction of the tunnels leading up to them, (b) the amount of soil excavated per unit time increases with soil temperature and moisture content. The amount of time and energy required to construct a typical nest were approximated using digging ability parameters determined in the lab. We estimate that if a colony was to move twice a year, it would expend around 20% of its energy intake and at least 6% of its worker time on nest excavation.Received 16 December 2002; revised 10 July 2003; accepted 23 July 2003.     

Incubation routine, body mass regulation and egg neglect in the Blue Petrel Halobaena caerulea

The incubation routine and mass changes of male and female Blue Petrel Halobaena caerulea were studied at the Kerguelen Islands to investigate factors influencing the durations of incubation stints and foraging trips at sea and the factors determining nest desertion and return to the nest.
The body mass at the start of an incubation shift and also when the bird was relieved varied throughout the incubation period, whereas the mass when birds deserted the nest was stable. Birds deserted the nest when their mass decreased to threshold, independent of the duration of the fast. Temporary egg neglect was observed in successful as well as in unsuccessful breeding attempts, but it increased the risk of breeding failure. The net and daily massgained at sea during the second part of the incubation period were higher than during the first part, suggesting an increase in food availability. During the first part, the mass gained at sea and time spent foraging were inversely related to the mass of the bird before it left the burrow, whereas a similar relationship did not occur thereafter.
The results suggest the occurrence of a fixed mass threshold when birds decide to leave the nest if not relieved by their partner. The mass when a bird left its nest inffuenced the time spent foraging or mass gained when food was scarce. Although decision rules to leave the nest or return from the sea are related to body condition. the possibility of neglecting the eggs temporarily enables Blue Petrels to regulate the trade-off between risks of breeding failure and risks of an increase in adult mortality. A model for behavioural decision to stop incubating or stop feeding, based on a variable set point, is proposed.     

Modeling Age and Nest‐Specific Survival Using a Hierarchical Bayesian Approach

Summary : Recent studies have shown that grassland birds are declining more rapidly than any other group of terrestrial birds. Current methods of estimating avian age‐specific nest survival rates require knowing the ages of nests, assuming homogeneous nests in terms of nest survival rates, or treating the hazard function as a piecewise step function. In this article, we propose a Bayesian hierarchical model with nest‐specific covariates to estimate age‐specific daily survival probabilities without the above requirements. The model provides a smooth estimate of the nest survival curve and identifies the factors that are related to the nest survival. The model can handle irregular visiting schedules and it has the least restrictive assumptions compared to existing methods. Without assuming proportional hazards, we use a multinomial semiparametric logit model to specify a direct relation between age‐specific nest failure probability and nest‐specific covariates. An intrinsic autoregressive prior is employed for the nest age effect. This nonparametric prior provides a more flexible alternative to the parametric assumptions. The Bayesian computation is efficient because the full conditional posterior distributions either have closed forms or are log concave. We use the method to analyze a Missouri dickcissel dataset and find that (1) nest survival is not homogeneous during the nesting period, and it reaches its lowest at the transition from incubation to nestling; and (2) nest survival is related to grass cover and vegetation height in the study area.     

Chemical communication during swarm emigration in the social wasp Polybia sericea (Olivier)

Communication during swarming was studied in the social wasp Polybia sericea in Brazil. After the adult population (swarm) evacuates following destruction of the nest, it forms a temporary (0.5- to 2-day) cluster on nearby vegetation and then emigrates to a new nest site. During both phases many adults drag the gaster over leaves and other substrates around the cluster and along the emigration route. The odour left on these objects is identical to that of the copious secretion of an exocrine gland opening at the base of the fifth (penultimate) sternite of the gaster. Following emigration the deposit of secretion in many individuals is depleted and shows signs of disturbance. Experimental evidence is presented to show that the swarm, if chased from its cluster site, reorients to it by means of the scent marks alone. It is further demonstrated that the swarm is guided to its new nest site by the trail of scent marks along the emigration route.     

How desert ants cope with enforced detours on their way home

Summary We ask whether desert ants (Cataglyphis fortis) perform path integration on their homeward as well as on their outward journey. If path integration does occur on the return journey, then, after an enforced detour, the ant's trajectory should point directly at its nest. To test whether this is so, ants were trained to forage at a spot 25 m from their nest. As an ant began its return journey to the nest, it was caught and transported to a test area where it was released either 2 m or 12 m from a wide barrier which obstructed its homeward path. The direction of the ants' trajectory after detouring around the barrier corresponded closely to that predicted on the assumption that the home vector is accurately updated during the detour.     

Do Solitary Bees Osmia cornuta Latr. and Osmia lignaria Cresson Use Proximal Visual Cues to Localize Their Nest?

Female Osmia repeatedly return to their nest to provision it with food and building material. The present study investigates the bees' nest localization performance by modifying visual cues in the near-vicinity of the nest. Each of several arrays of nesting holes was surrounded by four geometrical shapes. Removing some or all of the shapes reduced the proportion of direct returns but never prevented a bee from finding the appropriate array and, within that array, its own nest. The more the pattern was modified, the higher was the error score and the longer the delay, but no bee failed finally to find its nest. Shifting the pattern as well as the whole array of holes shifted homing orientation accordingly. There was no effect of the positions of the removed shapes, of contrast inversion, or of modifying the holes array. Our data are discussed in the light of the snapshot theory.     

Nest Predation Deviates from Nest Predator Abundance in an Ecologically Trapped Bird

In human-modified environments, ecological traps may result from a preference for low-quality habitat where survival or reproductive success is lower than in high-quality habitat. It has often been shown that low reproductive success for birds in preferred habitat types was due to higher nest predator abundance. However, between-habitat differences in nest predation may only weakly correlate with differences in nest predator abundance. An ecological trap is at work in a farmland bird (Lanius collurio) that recently expanded its breeding habitat into open areas in plantation forests. This passerine bird shows a strong preference for forest habitat, but it has a higher nest success in farmland. We tested whether higher abundance of nest predators in the preferred habitat or, alternatively, a decoupling of nest predator abundance and nest predation explained this observed pattern of maladaptive habitat selection. More than 90% of brood failures were attributed to nest predation. Nest predator abundance was more than 50% higher in farmland, but nest predation was 17% higher in forest. Differences between nest predation on actual shrike nests and on artificial nests suggested that parent shrikes may facilitate nest disclosure for predators in forest more than they do in farmland. The level of caution by parent shrikes when visiting their nest during a simulated nest predator intrusion was the same in the two habitats, but nest concealment was considerably lower in forest, which contributes to explaining the higher nest predation in this habitat. We conclude that a decoupling of nest predator abundance and nest predation may create ecological traps in human-modified environments.     

Size-assortative nest choice by the Japanese fluvial sculpin in the presence of male-male competition

Nest choice by the Japanese fluvial sculpin Cottus pollux and its relationship to male reproductive success, was examined in a natural habitat, central Japan. The larger males tended to occupy the deeper nest cavities, suggesting size-assortative nest choice by the species. Stepwise regression analysis showed that cavity area was correlated positively to male reproductive success. Nest choice experiments without a competitive male indicated an absence of size-assortative nest choice, but larger males tended to choose a large nest when another male was present, suggesting that size-assortative nest choice by the species is attributable to male-male competition for large nests, such being related to a resource-defence polygynous mating system.     

Les relations entre fourmis arboricoles et guêpes sociales sous les tropiques

Due to the brood that it contains, the nest of social wasps constitutes a major source of protein for eventual predators. In the tropics, ants are generally considered as the most efficacious among them. In the face of such predation, wasps have developed over the course of evolution a great number of strategies. In addition to guarding and defensive behaviours displayed by workers, social wasps have nests whose structure is a response to the predation pressure exerted by ants. Thus, the presence of a petiole attaching the nest to a natural support itself sometimes selected because of its limited accessibility constitutes a frequent example of architectural defence. The effectiveness of the petiole is often improved through the repeated application of repellent substances on its surface. In the same way, wasps that found their new societies through swarming construct nests protected by an envelope. In the American tropics, army ants which hunt on the ground and can rapidly take over a tree, regularly pillage wasp nests. Because no defensive strategy is efficacious against such predators, the choice of nest site becomes decisive. Paradoxically, it is by nesting in close proximity to an arboreal ant nest that certain wasp species have been able to find a way of responding to the threat exerted by other ants. These ants, which tolerate the presence of the wasp nest, are capable of efficaciously protecting the tree or the branch sheltering the nest.     

Ground-nesting bees determine the location of their nest relative to a landmark by other than angular size cues

Bees and wasps acquire a visual representation of their nest's environment and use it to locate their nest when they return from foraging trips. This representation contains among other features cues to the distance of near-by landmarks. We worked with two species of ground-nesting bees, Lasioglossum malachurum (Hymenoptera: Halictidae), Dasypoda hirtipes (Hymenoptera: Melittidae) and asked which cues to landmark distance they use during homing. Bees learned to associate a single cylindrical landmark with their nest's location. We subsequently tested returning bees with landmarks of different sizes and thus introduced large discrepancies between the angular size of the landmark as seen from the nest during training and its distance from the nest. The bees' search behaviour and their choice of dummy nest entrances show that both species of ground-nesting bees consistently search for their nest at the learned distance from landmarks. The influence of the apparent size of landmarks on the bees' search and choice behaviour is comparatively weak. We suggest that the bees exploit cues derived from the apparent speed of the landmark's image at their retina for distance evaluation.     

海拔梯度变化对黄缘蜾蠃筑巢结构及相关生物学特性的影响

黄缘蜾蠃(Anterhynchium flavomarginatum)是一种以鳞翅目幼虫为食的独栖性捕食昆虫,在生态系统中提供了重要的生物防治功能。2018—2019年,在广东车八岭国家级自然保护区通过人工巢穴收集了不同海拔梯度下(332—1007 m)该蜂的筑巢巢管,系统研究了黄缘蜾蠃的筑巢特征(巢管内径、巢室长度、巢室数量)以及该蜂的子代雌雄数和体型大小随海拔梯度的变化趋势。结果表明：海拔主要影响的是黄缘蜾蠃对巢管内径大小的选择,以及对前庭长度的分配,同时,黄缘蜾蠃对巢管内径的选择可以影响到后代性别比,这种策略主要体现在亲本对雌性子代的投资,而不是雄性子代。研究结果表明黄缘蜾蠃在不同海拔梯度下可根据外界环境压力调整其营巢和生殖策略,以提高种群对环境的适应性。     

Undirected Song Encourages the Breeding Female Zebra Finch to Remain in the Nest

Wild zebra finches sing frequently during the breeding season, but the vast majority of song is of the undirected song type that is not directed at any individual, and the function of which is obscure — it appears to be ignored by all potential recipients. It is sung close to the nest-site, has a peak in production during the egg-laying period, and diminishes thereafter. The incidence of undirected song is positively correlated with extra-pair courtship, a finding consistent with the hypothesis that it is a means of advertising availability for extra-pair matings. Typically, undirected song occurred outside the nest when the female was inside, and a positive relationship was found between the amount of singing given by the male during the 5-min interval immediately after the female entered the nest and the time she subsequently spent inside the nest. Keeping the partner inside the nest during her fertile period is an advantage to the male: it serves as a form of paternity protection against other males and it allows him opportunities to pursue his own extra-pair matings. Occupancy of the nest during laying is also a means of guarding against intraspecific brood parasitism, which was high at this colony.     

Predation risk induces changes in nest-site selection and clutch size in the Siberian jay

Life-history theory predicts that an individual should reduce its reproductive efforts by laying a smaller clutch size when high risk of nest predation reduces the value of current reproduction. Evidence in favour of this 'nest predation hypothesis', however, is scarce and based largely on correlative analyses. Here, we manipulated perceived risk of nest predation in the Siberian jay Perisoreus infaustus using playback involving a mixture of calls by corvid nest predators in the vicinity of nest sites. In response to being exposed to this acoustic cue simulating increased risk of nest predation, the jays chose a nest site offering more protective covering and reduced clutch size. This is the first experimental demonstration of clutch size adjustment and nest site selection as a result of phenotypic plasticity in an open nesting passerine reflecting a facultative response to the perceived risk of nest predation.     

若尔盖湿地保护区黑颈鹤巢期及影响因子

对鸟类巢期的研究不仅可以丰富鸟类繁殖生物学资料,也可为理解和研究鸟类的生态适应与进化提供重要线索和依据。2013—2014年3月份至7月份,在若尔盖湿地保护区及周边对55对繁殖黑颈鹤的营巢时长进行了研究,调查结果显示:黑颈鹤的营巢时长在0.5—40 d之间,平均巢期为(6.7±9.3)d;在其营造的4种巢型中,巢期长短依次为:泥堆巢草堆巢草墩巢岛地巢,且差异性极显著(P0.001),巢期与巢型显著相关(r=0.728);在其营巢的3种巢址生境中,巢期长短依次为:湖泊生境沼泽生境河流生境,且差异性极显著(P0.001),巢期与巢址生境显著相关(r=0.315);从不同营巢月份看,巢期长短依次为:4月份巢5月份巢6月份巢,且差异性极显著(P0.01),巢期与筑巢月份显著相关(r=0.664);巢期与巢体积大小具有显著相关性(r=0.856),即营巢时间越长巢体积越大。黑颈鹤的营巢时间长短主要受营巢生境、月份和做巢类型的影响。