Nest-site selection of the White Eared pheasant in southwestern Sichuan Province, China

From April to July 2003 and 2004, we surveyed the nest-site selection of the White Eared pheasant (Crossoptilon crossoptilon) in the Zhujie Monastery and in the mountain facing it in Sichuan Province, China. In this paper, we studied the nest characteristics and the clutch size of the pheasant. Habitat sampling method was used to determine the variables that might affect the nest-site selection of the White Eared pheasant. Chi-square test was used to identify which habitat type was likely to be preferred by the bird. Independent-samples t test and Mann-Whitney U test were used to find which variables were important for the birds’ nest-site selection. A total of 13 nests were found. Oak shrub was greatly preferred as nest sites (84.62%). Nests under a rock wall (7.69%) and a fallen tree (7.69%) were also found. The average clutch size of a White Eared pheasant is 7.33±0.54 (range, 5–11; n=12). Laying period was between April 27 and May 21. In the Zhujie area, 1 nest was in the forest and 11 nests were in oak shrubs. The species preferred oak shrub as its nesting habitat (χ ²=8.333, df=1, P<0.05). The bird was more likely to place its nest in sites with a high coverage, i.e. 0.5, 1, and 2 m above the ground (independent-samples t test, P<0.05), and with a large shrub diameter (Mann-Whitney U test, P<0.05). The species are more likely to prefer sites with plant cover, shrub cover (independent-samples t test, P<0.05), and shrub height (Mann-Whitney U test, P<0.05) in a relatively small range. Translated from Journal of Beijing Normal University (Natural Science), 2005, 41(2) (in Chinese)     

Nest location, clutch size and nest success in the Scarlet Ibis Eudocimus ruber

Breeding success and nest-site characteristics were studied during the 1996–1997 breeding season in a colony of Scarlet Ibises Eudocimus ruber in south-eastern Brazil to test the hypothesis that nest-site characteristics and clutch size affect nest success. Two nesting pulses produced young, the earlier being more successful. Predation accounted for most failures during the first pulse, wind destruction during the second. A third pulse with few nests produced no young. Adult Ibises abandoned nests when they lost sight of other incubating birds. Logistic regression analysis indicated that nest success during the first pulse was positively related to clutch size, number of nests in the nest tree and in the nearest tree, and negatively to the distance to the nearest neighbour. During the second pulse there were significant negative associations between success, nest height and distance to the fourth nearest nest, and a positive association between success and nest cover. The results agree with the 'selfish herd' hypothesis, indicating that nest aggregation may increase breeding success, but the nest-site characteristics affecting success can differ over the course of one breeding season.     

新疆阜康地区家麻雀的巢址选择

2013年7月和2014年5~7月,在新疆阜康地区对家麻雀(Passer domesticus)的巢址选择进行调查,以分析影响家麻雀巢址选择的生态因子。在研究区内共找到75个家麻雀的自然巢,筑巢生境为农田和防护林带,均在白杨(Populus adenopoda)林和胡杨(P.euphratica)林中的树上筑巢。其中,繁殖成功巢40个,繁殖失败巢20个,15个巢未记录到繁殖结果。在研究区内的居民房屋、墙洞等没有发现家麻雀的巢。采用逻辑斯蒂回归和主成分分析方法对筑巢地海拔(m)、筑巢树种、筑巢树高(m)、巢距路距离(m)、巢距地面高度(m)、巢上方盖度(%)、筑巢树胸径(m)、最近邻巢的距离(m)这些家麻雀的主要巢址参数进行分析,结果表明,影响新疆阜康地区家麻雀巢址利用的主要因素为巢距地面高度(m)、巢上方盖度(%)和巢距路距离(m)。对家麻雀繁殖成功巢(n=40)和繁殖失败巢(n=20)的巢址参数进行比较,两者差异不显著,因而推测,在研究区域的尺度内,家麻雀的巢址选择并不是影响其繁殖成效的主要因素。     

Multiscale Nest-Site Selection by Black-Capped Vireos

Abstract: We used an information-theoretic approach to investigate nest-site selection by black-capped vireos (Vireo atricapilla) at the landscape and habitat-patch scales on Fort Hood Military Reservation in central Texas, USA, during 2003 and 2004. We used a use-availability sampling design and logistic regression to compare woody cover characteristics at nests to random points in the landscape to determine habitat selection at the landscape scale. At the habitat-patch scale, we used matched case-control logistic regression to compare habitat measures at nests and random non-nest points to evaluate support for hypotheses concerning the influence of woody cover, nest-patch, and nest-site characteristics on black-capped vireo nest-site selection. At the landscape scale, we found strong support (Akaike wt [w_j] = 1.0) for a model with a cubic effect of percent woody cover and woody cover edge density. Sites with the greatest predicted probabilities of use had woody cover values between 30% and 60% and increasing amounts of edge. We found strong support (w_i = 0.93) for the global model at the habitat-patch scale that included characteristics of the nest site, nest patch, and woody cover within 25 m. Based on odds ratios and confidence limits, percent woody cover, cover below 2 m, cover type, and substrate height had the greatest effect on nest-site selection. The predicted probability a site was selected for a nest site increased with foliage cover below 2 m, taller substrates, deciduous cover, and decreased at high levels of percent woody cover (especially >80%). Texas red oak (Quercus buckleyi) was the most used nest substrate (100 of 358 nests), followed by shin oak (Q. sinuata var. breviloba; 86 of 358 nests) and Ashe juniper (Juniperus ashei; 44 of 358 nests). Black-capped vireos used Texas red oak and shin oak in greater proportion to their availability, whereas Ashe juniper was used less in proportion to its availability, suggesting vireos avoided this species. We suggest that managers promote dense deciduous cover for nesting habitat and maximize edge-to-area ratios to maintain spatial and structural heterogeneity.     

河南董寨国家级自然保护区发冠卷尾的巢址选择

2004年6~9月于河南董寨国家级自然保护区对发冠卷尾(Dicrurus hottentottus)的巢址选择进行了研究。野外调查中共发现发冠卷尾的巢47个,分布于针叶林、阔叶林和针阔混交林等3种植被类型中。我们在巢址样方(n=47)和对照样方(n=47)中对地形、距离与植被等因素(共15个变量)进行了调查,最终通过逐步判别分析表明,距山脊距离、距水源距离、乔木均高和灌木密度是影响其巢址选择的主要因子。     

白尾地鸦的巢址选择

2017年4和5月,在位于新疆塔克拉玛干沙漠南缘的和田地区民丰县对白尾地鸦（Podoces bidduphi）的巢址选择进行研究。共记录白尾地鸦巢12个,测量了巢参数,用Mann-Whitney U检验分析巢样方与对照样方的差异,用主成分法分析影响白尾地鸦巢址选择的主要因子。结果显示：1）白尾地鸦巢多筑于绿洲边缘的柽柳（Tamarix）灌丛,巢距地面高（109.1 ± 13.2）cm,巢深（8.5 ± 0.5）cm,巢厚（3.8 ± 0.4）cm,内径（13.9 ± 0.9）cm,外径（21.6 ± 1.3）cm;2）巢样方的植被物种数和植被盖度远高于对照样方;3）影响白尾地鸦巢址选择的主要因素为植被物种数及干扰,其中干扰主要指距道路以及距居民点的距离。综上所述,白尾地鸦的巢址选择受食物等生存需求和躲避干扰等安全因素的双重影响,是生存与繁殖权衡的结果。     

Do Fleas,and/or Old Nest Material,Influence Nest-site preference in Hole-nesting Passerines?

This study examined nest-site choice in a migratory population of pied flycatchers (Ficedula hypoleuca) and sympatric populations of three resident tit species (Parus major, P. caeruleus and P. palustris) in central Sweden. All four species are secondary-cavity nesters which naturally breed in pre-formed tree cavities but readily use artificial nest boxes. We asked whether flycatchers and tits discriminate between nest boxes that: 1. Are ‘empty’; 2. Contain old nests without ectoparasites (fleas Ceratophyllus sp.); or 3. Contain old nests with ectoparasites. We found that pied flycatchers preferred nest boxes containing old nests, regardless of whether these nests held parasites. In contrast, tits did not discriminate between the three types of boxes. Tits may pay a cost for their lack of choosiness: after the breeding season, tit nests contained more fleas than flycatcher nests. Nevertheless, parasites did not affect the choice of a nest site in any of the species studied. We suggest that the migratory flycatchers are in a hurry to start breeding upon arrival and use the presence of an old nest as a shortcut cue to assess nest-site quality. Also, they may save valuable time by copying the choice of previous breeders. Non-migratory tits may have more time to inspect nest sites, but do not seem to use the same cues in nest-site selection as the pied flycatcher.     

Reproductive ecology of Tibetan Eared Pheasant Crossoptilon harmani in scrub environment, with special reference to the effect of food

We studied the nesting ecology of two groups of the endangered Tibetan Eared Pheasants Crossoptilon harmani in scrub environments near Lhasa, Tibet, during 1996 and 1999–2001. One group received artificial food from a nunnery prior to incubation whereas the other fed on natural food. This difference in the birds' nutritional history allowed us to assess the effects of food on reproduction. Laying occurred between mid-April and early June, with a peak at the end of April or early May. Eggs were laid around noon. Adult females produced one clutch per year. Clutch size averaged 7.4 eggs (4–11). Incubation lasted 24–25 days. We observed a higher nesting success (67.7%) than reported for other eared pheasants. Provisioning had no significant effect on the timing of clutch initiation or nesting success, and a weak effect on egg size and clutch size (explaining 8.2% and 9.1% of the observed variation, respectively). These results were attributed to the observation that the unprovisioned birds had not experienced local food shortage before laying, despite spending more time feeding and less time resting than the provisioned birds. Nest-site selection by the pheasants was non-random with respect to environmental variables. Rock-cavities with an entrance averaging 0.32 m² in size and not deeper than 1.5 m were greatly preferred as nest-sites. The birds were also more likely to place their nests in denser high-scrub and closer to streams. In the study area, the low availability of both cliff habitats and high-scrub patches suggested a limitation of sites suitable for nesting, which could be reflected in the between-year re-use of nest-sites (8.9%) and intraspecific nest parasitism (3.8%). Despite the apparent preference for certain nest-site variables, we found no effect of these on clutch fate, suggesting that the risk of nest predation was random.     

The individual nest box as a super-stimulus for domestic hens

Following reports of inconsistent nest choice by hens in groups, choice of nest boxes by solitary hens was investigated. Thirty-two hens of a White Leghorn strain were each isolated with six nest boxes while they laid six eggs. From 16 hens, eggs were collected daily. Only one of these birds laid all her eggs in one nest box, and others used up to four boxes. The other 16 were allowed to accumulate eggs, and these were significantly more consistent in nest choice. Five used only one box. However, the other 11 of this group showed incomplete consistency.An explanation for inconsistent nest choice was suggested by a second experiment. The importance of enclosure in nest-site selection was tested in hens of White Leghorn and Rhode Island Red strains. Individuals about to lay their first egg were isolated with a choice of two types of nest box, selected from five types of different enclosure. Exposed nests, of similar dimensions to natural nests, were rarely used by either strain. By contrast, more enclosed nests were strongly selected. These results indicate that enclosure is an important stimulus in nest-site selection, and that artificial nest boxes, which are more enclosed than natural sites, act as super-normal stimuli (or “super-stimuli”). Choices between super-stimuli are likely to be equivocal, which accounts for inconsistency in the use of nest boxes and other features of the nesting behaviour of domestic hens.     

新疆北部白冠攀雀的巢与巢址选择

2008年4—7月,在新疆北部对白冠攀雀巢址选择进行了研究。白冠攀雀的营巢习性特殊,巢呈囊袋状,结构甚为精致。对于白冠攀雀巢的研究,采用总面积调查法,进行地毯式的搜寻,并结合标图法对其进行标记,绘制分布图。研究结果共发现巢125个,营巢位于于临近湖泊、河流等水域附近的柳树、杨树、桦树等阔叶树上。营巢树种以柳树为主,占68.80%。巢的高度平均为(5.3±2.5)m,营巢于乔木的中下部（约1/3处）,约70%的巢离河边不足30 m。对于巢址选择的研究,将原始记录中与巢址选择有关的特征变量进行主成分分析,分析表明,影响白冠攀雀巢址选择的主要因素有4种,依次为：郁闭度因素（包括营巢树胸径、巢上郁闭度）、营巢树种因素(包括营巢树种、树高、巢位高度和乔木种类)、方位因素（包括距河边距离和巢向）、食物与巢材因素。     

Breeding biology of Eared Quetzals in the Sierra Madre Occidental, Mexico

ABSTRACT.   Eared Quetzals ( Euptilotis neoxenus ), a threatened species, are one of the least studied trogons in Mexico. We monitored 29 Eared Quetzal nests in the Chihuahuan portion of the Sierra Madre Occidental from 1998 to 2003. All nests were in tree cavities, and the mean tree and nest cavity heights ( N = 14) were 16.9 ± 7.8 m and 11.4 ± 4.1 m, respectively. The mean clutch size was 2.8 ± 0.9 eggs ( N = 28), the incubation period lasted 22 d ( N = 1), and nestling periods ranged from 29 to 31 d ( N = 5). Both adults incubated eggs and fed nestlings. Of 80 eggs, 70 hatched (87.5%) and 67 of 70 young fledged (95.7%). Twenty-five of 29 nests (86.2%) produced at least one fledgling. One nest was predated, and two failed when nest trees fell. Higher rates of nest predation have been reported for other species of trogons. However, fewer potential predators, such as snakes and mammals, are present in the Sierra Madre than in tropical zones where most trogon species occur. In addition, antipredator behaviors, including nestlings with calls resembling a snake and nests with an unpleasant odor, may contribute to the high nesting success. The main limiting factors for Eared Quetzals in the northern Chihuahua may be competition for cavities with other secondary cavity-nesters, and the failure of nests when snags fall.     

原鸡海南亚种的巢址特征

选择适宜的巢址对降低巢捕食风险,提高繁殖成效有重要意义。2008年3—7月,在海南省大田国家级自然保护区,采用随机样线法结合访问法在各种生境类型中系统地寻找原鸡海南亚种(Gallus gallus jabouillei)的巢,并在野外追踪观察基础上用样方法对原鸡的巢址选择进行研究。共记录到原鸡的巢16个,以巢为中心选取样方并测量反映巢址的13个特征生境参数,同时分析16个对照样方以进行比较,并通过主成分分析探讨影响巢址选择的主导因子。结果表明：（1) 原鸡的巢位于密集的丛生草本下或低矮的灌木丛基部。营巢背景多样,其中位于草本植物下10个(62.5%);灌草丛5个(31.3%);灌木下1个(6.25%)。（2) Mann–Whitney U检验的结果显示,原鸡偏好于比较开阔、地面落叶稀少而靠近的小道和林缘的位置营巢。（3) 主成分分析表明,植被盖度因子和空间位置因子贡献率最大,在降低巢捕食风险中有重要价值,是影响原鸡巢址选择的主要因素。     

Age-specific nest-site preference and success in eiders

Variation in nest concealment is puzzling given the expected strong selection for safe nest sites. Selecting a concealed nest may decrease the risk of clutch predation but hinder parents from escaping predators, providing a possible solution to this paradox. Because the relative value of current versus future reproduction may vary with breeder age or state, nest concealment may also vary as a function of these attributes. We tested four predictions of the female and clutch safety trade-off hypothesis in eiders (Somateria mollissima): (1) nest concealment is negatively related to escape possibilities, (2) our capture rate of females is higher in covered nests, (3) egg predation is higher in open nests, and (4) overall nest success is unrelated to nest habitat. We also analysed nest microhabitat preferences and nest success relative to breeder age and body condition, controlling for nest spatial centrality. As expected, nest concealment and potential escape angle were negatively related, and capture by us, indicating female predation vulnerability, increased with nest cover. Clutch size was smaller in open nests, suggesting higher partial clutch predation, while it was larger among experienced and good-condition breeders. The probability of successful hatching was unrelated to nest habitat, positively associated with breeder experience, and negatively associated with hatching date. Experienced females selected more concealed and centrally located nests without sacrificing potential escape angles. The age-specific spatial distribution of nests on islands was unrelated to nest initiation dates, indicating no apparent competition. The age-specific preference of eiders for concealed nests may reflect declining reproductive value with age or confidence in surviving despite selecting a concealed nest. The apparently positive relationship between female age and survival and fecundity in eiders refutes the former alternative. Individual improvement in choosing safe nest sites, coupled with differential survival of individuals performing well, most likely explains age-specific nest-site preference and success.     

Nest-site preference and maternal effects on offspring growth

Maternal preferences for oviposition sites are assumed to beadaptive, but offspring fitness is not always higher at preferredsites and, thus, further study of the selection pressures thatinfluence oviposition behavior is warranted. Among birds, predationis regarded as the primary agent of selection on nest-site microhabitatpreferences, but alternatives are rarely considered. We testedthe hypothesis that avian nest-site preferences are an adaptiveresponse to fitness costs imposed by variation in nest-sitemicroclimate. We documented that Chestnut-collared Longspurs(Calcarius ornatus) strongly preferred to orient nests towardsthe southeast and showed that this preference influenced microclimate:nests facing southeast had the highest midday temperatures.Yet, preferences were not adaptive because nestlings in nestswith the preferred orientation gained mass at a slower rate,had retarded skeletal growth, and reached a smaller final size.We experimentally tested this result by altering orientationof nests and confirmed, for the first time, that variation innestling growth was causally linked to variation in nest microclimatearising from nest-orientation preferences. Adults respondedto the high temperatures at preferred southeast-facing nestsby spending more time shading young from the sun, apparentlyattempting to ameliorate heat costs. This response, however,resulted in parents spending less time feeding young, potentiallyexplaining slower growth in these nests. Direct effects of highertemperatures may also play a role in slower growth. Althoughwe lack an explanation for this apparently maladaptive preference,these results demonstrate that nest-site choices of birds canyield fitness costs imposed by variation in nest microclimate.     

郑州郊区崖沙燕(Riparia riparia)的巢址选择

2014年3—8月,采用样方法对分布于河南省郑州市郊区的4处崖沙燕(Riparia riparia Linnaeus 1758)营巢地的13个生境因子进行了调查,测定了巢址样方和对照样方各160组数据,并利用Mann-Whitney U检验对这些数据的显著水平进行了检验;最后采用逐步判别分析(stepwise discriminate analysis)方法确定影响崖沙燕巢址选择的主要生态因子,并建立了标准化的典则判别函数。结果表明,1)崖沙燕洞巢的洞口横径(8.46±0.79)cm,纵径(8.30±0.79)cm,巢洞深(87.80±11.97)cm,巢室长径(11.25±1.33)cm,短径(10.43±1.33)cm,巢室高(9.99±1.33)cm;2)巢址样方与对照样方在植被均高、植被密度、坡位、坡度、崖高、崖长、崖龄及干扰度等8个方面差异达到显著水平,崖沙燕偏好选择的洞巢周围植被较高(97.24±8.42)cm,植被密度较大(64.34±7.15)株/m~2,坡度较大(83.78±0.35)°、上坡位(1.41±0.04)、崖较高处(7.54±0.13)m、崖壁较长(51.18±3.54)m、崖龄较短(2.41±0.05)月及人类干扰较低(1.94±0.06);3)逐步判别分析结果表明,影响崖沙燕营巢地选择的主要生境因子是坡位、崖龄和干扰度,标准化的典则判别函数为y=0.753×坡位+0.681×崖龄+0.288×干扰度。建议在城市化建设过程中针对崖沙燕的巢址选择特性建立合理的保护措施。     

Old nests are cues for suitable breeding sites in the Eurasian penduline tit Remiz pendulinus

Nest-sites often have a major influence on avian reproductive success. The use of reliable cues that assist nest-site selection should thus be favoured by natural selection. The old nests have been known to serve as a cue in nest-site selection in several species. To find out whether the old nests act as cue in nest-site selection in the Eurasian penduline tit Remiz pendulinus , we carried out two experiments in southern Hungary, where the penduline tits breed around fishponds and build sophisticated pendulous nests on tree branches that often hang over water. In April 2006, we choose 20 groups of two nearby trees, and hung an old nest on one of the trees in each group. The male penduline tits choose 12 of these groups to build a new nest, and every of the twelve nests were built on trees with an old nest. This suggests that the old nests serve as a cue in the selection of breeding sites for males when they enter a habitat. To find out whether the old nests are cues of plentiful nest building material, or to signal high quality breeding areas, we carried out a second experiment in 2007 by selecting 13 groups of three nearby trees. A "worn-out" old nest was hung on one of the trees, a "re-utilize" type of old nest on another tree, whereas the third tree was left without an old nest in each group. The rationale was that while the worn-out material of the old nests is of no use in building the new nests, material of the "re-utilize" nests is good enough to be used for building new nests. Males built a new nest in 10 of the 13 groups, and eight of the new nests were built on trees with an old nest. Of the eight new nests, five were built on trees with a "worn-out" old nest and three on trees with a "re-utilize" type of old nest. It appears that for the penduline tit males it is the presence of an existing old nest and not the quality of the old nest material that serves as cue during the selection of the suitable breeding sites.     

Testing the importance of individual nest-site selection for a social and group-living vulture

Nest-site selection by species is expected to be adaptive and lead to improved breeding productivity, but in some settings, there exist mismatches between preferred nesting habitat and breeding productivity. We tested the expectation that nest-site selection is adaptive in a sample of 63 nests of a long-lived social species that breeds and forages in groups: the critically endangered white-backed vulture (Gyps africanus). By studying breeding groups in the same area, we controlled for landscape-level effects on habitat selection and investigated how fine-scale nest-site characteristics affect breeding productivity. We developed models to assess how nine characteristics of nest sites selected by breeding vultures compared with 70 random trees and tested associations between these characteristics and breeding productivity. White-backed vultures selected nest sites in taller trees (>7 m), but neither tree height nor any other nest-site characteristics had a clear effect on breeding productivity. Vultures selected nest trees closer to each other than random trees, and the associations between nest density, nearest neighbour distance and breeding success were all positive. These positive associations and the absence of an observable effect between nest-site characteristics and breeding productivity suggest that for this semi-colonial breeder, the social imperative of proximity to conspecifics (i.e., nesting near other vultures and group foraging) may be more important than individual nest-site selection.     

The influence of nest-site characteristics on the nesting success of the Karoo Prinia (Prinia maculosa)

Choice of nest site has important consequences for nest survival. We examined nest-site characteristics relative to nest success in Karoo Prinias breeding in coastal dwarf shrubland, where high nest predation is the main cause of nest failure. Initially, we compared nests that failed during the building, laying, incubation and nestling stages and those from which young were successfully raised, to test whether nests that survived to progressive stages in the nesting cycle differed in their nest-site characteristics. Subsequently, we compared the characteristics of successful nests with those of unsuccessful nests. The nest-site characteristics considered included nest height, nest-plant height, nest-plant species, distance from lateral foliage edge, nest concealment, nest-patch heterogeneity and vegetation cover at four different heights. We were unable to distinguish between the nest-site characteristics of nests that failed during the various stages of the nesting cycle. Concealment was the main nest-site characteristic that differentiated successful nests from unsuccessful nests, with successful nests being located in more concealed sites. The other variables that contributed to the discrimination between successful and unsuccessful nests by discriminant function analysis included nest-plant type and distance from edge, which are also directly related to concealment. This suggests that nest concealment is the most important variable influencing nesting success at this site, which has a preponderance of visually-oriented predators.     

利用天然树洞繁殖的五种鸟的巢位特征及繁殖成功率

对吉林省左家自然保护区次生阔叶林中的大山雀 ( Parusmajor)、沼泽山雀 ( Paruspalustris)、普通跓( Sitta europacea)、白眉姬? ( Ficedula zanthopygia)和灰椋鸟 ( Sturnus cineraceus) 5种利用天然树洞繁殖的次级洞巢鸟进行了巢位选择和繁殖成功率研究。本研究中共发现 1 41巢。五种鸟对树洞类型的选择存在种间差异 ,普通跓不利用裂洞 ,沼泽山雀不利用啄洞 ,其它 3种鸟对 3种洞均有利用 ,但有一定的倾向性。对 5种鸟 9个巢位变量的比较中 ,只有洞口方向差异不显著 ( p >0 .0 5 ) ,其它 8个变量均差异显著 ( p<0 .0 5 ) ,该结果说明 5种次级洞巢鸟对巢位的选择具有其各自的需求。洞口横径、洞口纵径、洞处树直径、洞内径、巢距地高是巢位选择重要变量 ,它们决定不同种类对树洞的利用。巢损失多数出现在产卵之前和孵化阶段 ,44个繁殖失败的巢中有 35个在这两个阶段损失。大山雀的巢成功率最低 ,灰椋鸟的巢成功率最高。 5种鸟的孵化率都超过 90 %。人为破坏和动物捕食是繁殖失败的主要原因 ,占总数的 61 .4%。洞巢鸟巢位选择中的重要变量影响繁殖成功。普通跓繁殖是否成功受洞口横径和巢高影响 ,沼泽山雀受洞口纵径、树胸径和洞内径影响 ,大山雀受洞口横径、巢高和洞内径影响 ,灰椋鸟受洞内径和洞深影