植物空间分布格局中邻体距离的概率分布模型及参数估计

最近邻体法是一类有效的植物空间分布格局分析方法,邻体距离的概率分布模型用于描述邻体距离的统计特征,属于常用的最近邻体法之一。然而,聚集分布格局中邻体距离(个体到个体)的概率分布模型表达式复杂,参数估计的计算量大。根据该模型期望和方差的特性,提出了一种简化的参数估计方法,并利用遗传算法来实现参数优化,结果表明遗传算法可以有效地估计的该模型的两个参数。同时,利用该模型拟合了加拿大南温哥华岛3个寒温带树种的空间分布数据,结果显示:该概率分布模型可以很好地拟合美国花旗松(P.menziesii)和西部铁杉(T.heterophylla)的邻体距离分布,但由于西北红柏(T.plicata)存在高度聚集的团簇分布,拟合结果不理想;美国花旗松在样地中近似随机分布,空间聚集参数对空间尺度的依赖性不强,但西北红柏和西部铁杉空间聚集参数具有尺度依赖性,随邻体距离阶数增加而变大。最后,讨论了该模型以及参数估计方法的优势和限制。     

Social Aggregation in Pea Aphids: Experiment and Random Walk Modeling

From bird flocks to fish schools and ungulate herds to insect swarms, social biological aggregations are found across the natural world. An ongoing challenge in the mathematical modeling of aggregations is to strengthen the connection between models and biological data by quantifying the rules that individuals follow. We model aggregation of the pea aphid, Acyrthosiphon pisum. Specifically, we conduct experiments to track the motion of aphids walking in a featureless circular arena in order to deduce individual-level rules. We observe that each aphid transitions stochastically between a moving and a stationary state. Moving aphids follow a correlated random walk. The probabilities of motion state transitions, as well as the random walk parameters, depend strongly on distance to an aphid''s nearest neighbor. For large nearest neighbor distances, when an aphid is essentially isolated, its motion is ballistic with aphids moving faster, turning less, and being less likely to stop. In contrast, for short nearest neighbor distances, aphids move more slowly, turn more, and are more likely to become stationary; this behavior constitutes an aggregation mechanism. From the experimental data, we estimate the state transition probabilities and correlated random walk parameters as a function of nearest neighbor distance. With the individual-level model established, we assess whether it reproduces the macroscopic patterns of movement at the group level. To do so, we consider three distributions, namely distance to nearest neighbor, angle to nearest neighbor, and percentage of population moving at any given time. For each of these three distributions, we compare our experimental data to the output of numerical simulations of our nearest neighbor model, and of a control model in which aphids do not interact socially. Our stochastic, social nearest neighbor model reproduces salient features of the experimental data that are not captured by the control.     

种群分布格局的多尺度分析

种群分布格局的分析对于了解种群空间分布规律以及种内与种间关系具有重要的意义。最近邻体分析方法 (Nearestneighboranalysis, NNA) 作为种群空间分布格局的重要分析方法, 仅局限于种群格局的单尺度分析。改进NNA方法以应用于种群格局的多尺度分析, 将有助于解决种群格局的尺度依赖性。该文在前人研究的基础上提出扩展最近邻体分析方法 (Extendednearestneighboranalysis, ENNA), 也即在传统Clark_Evans指数公式的基础上增加一个距离尺度参数d (m), 并定义其所对应的Clark_Evans 指数CE (d) 的计算公式及其相应的显著性检验计算公式 (u (d) ) 分别为 :CE (d) =rdA/rdE= (1Nd∑Ndi=1 rdi) / (0.5Ad/Nd+0.0 5 14Pd/Nd+0.0 4 1Pd/Nd3 /2 ) 和u (d) = (rdA-rdE) /σd, 在距离尺度d (m) 范围内, 参数rdA指样地内各个体与其最近邻体间距离的平均值 (m) 、rdE指相同环境中个体呈随机状态时最近邻体距离的平均值 (m) 、Nd 为样地内个体总数、rdi为第i个个体与其最近邻体间的距离 (m) 、Ad 为样地面积 (m2 ) 、Pd 为样地周长 (m) 和σd 代表标准差。ENNA尺度变换采用与分形理论中计算沙盒维数相类似的过程, 而格局类型判断的标准与传统最近邻体分析方法相同。传统最近邻体分析结果是EN NA中距离尺度d取最大值dmax时的一个特例。以广东省黑石顶自然保护区针阔叶混交林中的马尾松 (Pinusmas soniana) 、黄牛奶树 (Symplocoslaurina) 、水栗 (Castanopsisnigrescens) 、鼠刺 (Iteachinensis) 和桃金娘 (Rhodomyrtustomentosa) 等 5个代表性种群为例, 在地理信息系统软件ArcViewGIS技术平台上进行的实例研究显示, 5个种群均表现出不同程度的尺度相关性。由此表明, 该文提出的新方法ENNA能够检测出种群空间分布格局的尺度依赖性, 获得关于种群空间分布格局的多尺度信息, 是进行种群空间格局多尺度分析的有效方法。     

Quartered neighbor method: A new distance method for density estimation

Quantitative data are essential to an appropriate characterization of vegetation. In the past few years, considerable attention has been paid to vegetation sampling techniques. A number of methods have been developed for plant density estimations that utilize spacing distances instead of fixed-area quadrats. In this paper, we review the main distance methods for estimating density and propose a new distance method denominated the quartered neighbor method. In this method, the sampling point is considered the center, and the area around it is divided into four quadrants. The distance from the closest individual in each quadrant to its closest neighbor in the same quadrant is measured, and the average of them is the distance we need. It is actually an integration of two old distance methods, the nearest neighbor method, and the point-centered quarter method. With our new method and an old distance method (the point-centered quarter method), we calculated the average spacing distances of the Larix principis-rupprechtii population in the larch forests of the Donglingshan Mountain. Comparing the two methods with the quadrat method, we found they were almost the same in accuracy, but the precision of the new one was better. Meanwhile, it is adequate in sampling intensity and adaptable for general use in rapid ecological survey work.     

Properties of the nearest neighbor interchange metric for trees of small size

The crossover or nearest neighbor interchange metric has been proposed for use in numerical taxonomy to obtain a quantitative measure of distance between classifications that are modeled as unrooted binary trees with labeled leaves. This metric seems difficult to compute and its properties are poorly understood. A variant called the closest partition distance measure has also been proposed, but no efficient algorithm for its computation has yet appeared and its relationship to the nearest neighbor interchange metric is incompletely understood. I investigate four conjectures concerning the nearest neighbor interchange and closest partition distance measures and establish their validity for trees with as many as seven labeled vertices. For trees in this size range the two distance measures are identical. If a certain decomposition property holds for the nearest neighbor interchange metric, then the two distance measures are also identical at small distances for trees of any size.     

Changes in activity,spatial pattern and social behavior in calves after grouping

The behavior of 2 groups of 6 calves that were managed in 2 different ways were observed, and the development of their behavioral patterns, spatial patterns and social behavior in the groups were discussed, together with the effect on these processes of their social experience before grouping.Twelve 5-month-old Holstein steers, reared alone from one week of age, were divided into 2 groups of 6 calves each; Groups A and B. Calves in Group A were penned together in a 14.4 × 28.8 m pen, and the position and behavior of individuals was observed throughout a continuous 153-h period at 15-min intervals. Aggressive behavior between calves was also recorded. The position of calves was recorded as coordinates on a grid on the pen floor. There were 8 × 16 squares in the grid, and each square measured 1.8 × 1.8 m.Group B was further divided into 3 groups of 2 calves each, which were kept in 9.6 × 14.4 m pens. The pair-mates were changed every 3 days in order to combine all possible pairs in the group. After this treatment, calves were all housed together in a 14.4 × 28.8 m pen, and observed using the same methods and for the same duration as Group A.The lying pattern of Group A was not diurnal until the latter half of the observation, while calves in Group B showed clear-cut diurnal variations from the initial stages. Concerning the spatial patterns; the mean distance to nearest neighbor in Group A tended to decrease and become stable. The ratio between the mean distance to nearest neighbor and the distance expected in random distribution also declined from 0.7 to a significant aggregation of 0.5 (P < 0.05). For Group B, a similar change in the mean distance to the nearest neighbor was observed, although this showed significant aggregation from the first 24-h period (P < 0.05). The mean area occupied by a group in each 24-h period, for both groups, declined for 72 h after grouping and became stable at around 18 m², for both groups, thereafter. The frequency of aggression in Group A declined from 23 times in the first 24-h period to 9 times at the end of the observation period. For Group B, the aggression frequency was 53 times in the first 24-h period, thereafter decreasing rapidly.     

SPATIAL PATTERNING AND COMPETITION IN AN ASPEN-WHITE PINE SUCCESSIONAL SYSTEM

The spatial patterning of and competition between established large-toothed aspen (Populus grandidentata) and invading white pine (Pinus strobus) were examined in a 65-yr-old forest system at the AuSable Trails Institute of Environmental Studies, Kalkaska County, Michigan. Density, diameter, and distance measures were recorded for tree species on two 40 × 40 m grids containing 64 quadrats each 5 × 5 m. Several indices of dispersion were used to assess pattern and regression analysis of nearest neighbor distance to tree diameter provided an index of competition. The results indicate strong aggregation for both aspen and pine on a large scale, but regularity of pattern for pines in relation to their nearest neighbor. This regularity appears to be due to competition with established aspens and suggests that the spatial patterning of the aspens acts to control the spacing and subsequent development of the invading white pines.     

大兴安岭次生林区优势种落叶松分布格局及竞争作用

竞争是形成特定群落结构、构成分布格局的基本驱动力之一,树种的空间分布和大小并不是相互独立的,而是广泛受到竞争过程影响。在大兴安岭设置一块具有代表性的天然次生林恢复样地,采用点格局分析中的最近邻体距离G（r）函数、双关联函数g（r）和基于个体胸径标记的点格局分析方法同时结合4种点格局零模型（完全随机模型、均值托马斯模型、随机标签模型、先决条件零模型）研究分析大兴安岭次生林区优势种落叶松不同生活史阶段的分布格局、关联性及竞争作用。研究结果显示：落叶松不同发育阶段分布格局不同、同一发育阶段不同研究尺度分布格局也不同;落叶松种群内存在潜在的竞争、且竞争作用与龄级和研究尺度有关;落叶松幼龄个体在小尺度（r<5m）下的聚集分布是由扩散限制作用和竞争作用所导致;落叶松种群内成龄与幼龄个体间有较强的正关联性、成龄个体对幼龄个体在小尺度下有明显的庇护作用;标记点格局分析方法在检测植物群落中的竞争作用时敏感性较高。     

A generalization of Pielou's index of non-randomness.

Pielou's index of non-randomness a measuring the distribution of point spatial patterns on a plane generalizes to an index in n-dimensional Euclidean space Eⁿ. This defines an index of non-randomness measuring the extent of regularity, randomness, or aggregation in distributions of point spatial patterns in Eⁿ.     

Multi-scale turtle dove nest habitat selection in a Mediterranean agroforestry landscape: implications for the conservation of a vulnerable species

Determination of factors affecting nest habitat selection is a major topic in avian ecology, with strong implications for conservation purposes especially for the species with unfavorable status. The turtle dove (Streptopelia turtur) is a vulnerable species that has undergone a rapid and serious decline across its distribution range. I investigated the effect of different variables at two spatial scales (10-m radius, nest site; and 100-m radius, landscape) on the probability of presence of turtle dove nests in an agroforestry system of Central Morocco. Topography, habitat structure, human disturbance, and land use parameters were measured at nests (n?=?70) and random points (n?=?70) at both scales. Generalized linear model analyses showed that, at the nest site scale, tree height best explained occurrence of turtle dove nests (with nest occurring preferentially in smaller trees). At the landscape scale, nest occurrence probability decreased with elevation and distance to the nearest forest edge, and increased with forest cover and distance to the nearest habitation. Comparison of explanatory power of the single-scale models showed that the most relevant scale was the nest site level, followed by landscape scales, but the model including both nest-scale and landscape-scale variables was best. The variation partitioning analysis confirmed this pattern. In study area, the turtle dove nest habitat selection process occurs within a relatively small scale, but the joint effect of variables at the two scales is relevant. From a practical perspective, it would be interesting to reproduce the same experimental approach on other Mediterranean breeding habitats (agricultural and other forest habitats) to find out if this species would adopt the same nest habitat selection pattern.     

Neighbourhood analysis as an indicator of spatial requirements of broiler chickens

The appropriate stocking density for broiler chickens is a much discussed topic in animal welfare. To determine at which stocking density the level of crowding becomes aversive to 4–6-week-old broiler chickens, spatial distribution and behaviour of groups stocked at 8, 19, 29, 40, 45, 51, 61 or 72 birds per 3.3 m² were analysed. Spatial distribution was evaluated using three different indices: inter-individual distances, nearest neighbour distances and Dirichlet polygon areas. The assumption was that broilers would increase the distance to their pen mates if high densities (i.e., close proximity to pen mates) were experienced as aversive, whereas they would decrease this distance if close proximity was experienced positively. Increased distances to pen mates would lead to increased nearest neighbour distances and a more homogeneous distribution (i.e., lower variation of inter-individual distances and of Dirichlet-polygon size) than expected by chance. The distribution expected by chance was determined from both a random distribution and a ‘resource-corrected’ random distribution (which incorporated environmental influences on spatial distribution but excluded social ones).Behavioural observations showed that at higher stocking densities more sitting bouts (P = 0.003) and adjustments of the sitting and lying posture (P < 0.001) occurred. It was also found that nearest neighbour distance varied according to behaviour (P = 0.001). Birds that were eating/drinking were further apart from their nearest neighbour than birds that were foraging, preening, adjusting their sitting or lying posture or showing “other” behaviour.The results from all three methods of spatial analysis suggested that broilers in groups ≥19 birds per 3.3 m² (ultimately equivalent to 15 kg/m²) started to experience the proximity of conspecifics as aversive at some point during the last 3 weeks of rearing. However, nearest neighbour distance analysis showed evidence of aversiveness earlier in life than the other methods of analyzing spatial distribution (variation in inter-individual distance and polygon size), suggesting that nearest neighbour distance is the more sensitive indicator of space requirements.When uneven use of the different areas within the pen was reflected in the expected distribution (i.e., for comparisons to the resource-corrected random distribution) different results were obtained than when such measures were omitted (i.e., for comparisons to the random distribution). As such, this study emphasises the importance of accounting for environmental influences on distribution within a pen.     

Experimental field test of spatial variation in rodent predation of nuts relative to distance and seed density

The spatial context in which seed predation occurs may modify the spatial structure of recruitment generated by seed dispersal. The Janzen–Connell (J-C) model predicts that granivores will exert greater pressure on the parent plant or at those sites where the density of dispersed seeds is higher. We have investigated how the probability of post-dispersal survival of Juglans australis varies with nut density across a hierarchy of spatial scales. We experimentally evaluated the survival of 3,120 nuts at three spatial scales: meso-scale (≤1.5 ha), as forest sites with two densities of fruiting J. australis individuals; intermediate scale (<0.2 ha), as individual trees with two experimental crop sizes; small scale (<0.1 m²), as microsites with two factors (number of nuts and distance from source). Nut removal coincided with seed predation, a condition that allowed us to test the density-dependent seed predation hypothesis. We found that the probability of nut survival was greater at forest sites with higher J. australis density. Nut survival was not affected by nut density in the seed shadow of individual specimens: at sites where J. australis density was greater, the proportion of surviving nuts did not differ between microsites located at different distances from the parent plant, but it was greater at microsites with greater initial nut density. Nut survival depended on the scale at which rodents responded to nut density, being negatively density dependent at the meso-scale and spatially random at intermediate and small scales. At the meso-scale, excess nut supply increased the probability of nut survival, which is in agreement with a model of granivore satiation near the seed source. Rodent satiation at the meso-scale may favour maintenance of sites with high J. australis density, where individual trees may have greater probabilities of passing their genes onto the next stage of the dispersal cycle.     

Quartered neighbor method: A new distance method for density estimation

Quantitative data are essential to an appro-priate characterization of vegetation. In the past few years, considerable attention has been paid to vegetation sampling techniques. A number of methods have been developed for plant density estimations that utilize spacing distances instead of fixed-area quadrats. In this paper, we review the main distance methods for estimating density and propose a new distance method denominated the quartered neighbor method. In this method, the sampling point is considered the center, and the area around it is divided into four quadrants. The distance from the closest individual in each quadrant to its closest neighbor in the same quadrant is measured, and the average of them is the distance we need. It is actually an integration of two old distance methods, the nearest neighbor method, and the point-centered quarter method. With our new method and an old distance method (the point-centered quarter method), we calculated the average spacing distances of the Larix principis-rupprechtii population in the larch forests of the Donglingshan Mountain. Comparing the two methods with the quadrat method, we found they were almost the same in accuracy, but the precision of the new one was better. Meanwhile, it is adequate in sampling intensity and adaptable for general use in rapid ecological survey work.     

Nets with distance bias

A distance bias is imposed on the probability of direct connection between every pair of points in a random net. The probability that there exists a path from a given point in the net to another point is now a function of both the axone density and the distance between the points. A recursion formula is derived in terms of which this probability can be computed. The rate of spread of an epidemic where probability of contact depends on the distance between the individuals can also be computed from the recursion formula.     

从空间分布特征认识珍稀植物领春木的种群动态

领春木(Euptelea pleiosperrnum)系第三纪孑遗植物和东亚特有种,目前已被列为国家Ⅲ级重点保护植物.基于空间定位数据以最近邻体距离统计研究了神农架地区领春木的空间分布特征,比较幼苗(DBH≤2.5cm)、幼树(2.5～7.5cm)和成树(＞7.5cm)各径级(代表各生活史阶段)形成的时间序列上的空间格局差异,进而探讨空间格局与立苗、补员、种内竞争等种群动态过程的相互关系.结果显示,在邻域尺度上,领春木的空间格局呈聚集态;幼苗(或幼树)的大小与其距离最近幼树(或成树)的远近没有相关性,幼树(或成树)周围一定距离以内出现同等大小个体的概率约等于幼苗(或幼树)出现的概率,且幼树与最近幼苗(或成树与最近幼树)的平均距离与幼树之间(或成树之间)的平均最近邻体距离没有显著差异;任意个体的大小、任意个体与相应最近邻体的大小之和与相应的最近邻体距离均为显著的正相关关系,但幼树间的最近邻体距离并不大于幼苗随机死亡产生的最近邻体距离,成树间最近邻体距离也不大于幼苗+幼树随机死亡产生的最近邻体距离.这些结果表明,领春木的聚集分布可能与种子散布、生境异质性对立苗格局的作用有关;已定植的大个体可能不限制其邻域内小个体的布局与生长,但是长期的补员过程与邻体间的相互作用不无关系;邻体间存在一定程度的竞争作用,但是竞争强度并未充分激化至发生距离依赖的死亡.     

天山云杉种群空间格局与动态

天山云杉(Picea schrenkiana)林是天山林区的重要针叶林。研究调查了两块分别代表天山云杉不同演替阶段的标准地,应用Ripley’s K系数法研究了天山云杉种群空间格局与动态。结果表明：天山云杉是聚集型种群,天山云杉活立木、枯死木、天山桦(Betula tianschanica Rupr．)和天山柳(Salix tianschanica Rgl．)的空间格局均为聚集型;天山云杉枯死木的聚集强度大于天山云杉活立木的聚集强度;天山桦和天山柳的聚集强度大于天山云杉枯死木的聚集强度;天山桦和天山柳的空间格局随种群所处的演替阶段不同而不同,增长型种群在所有尺度上其空间格局都为聚集型,在大于70m尺度上表现为均匀格局,而天山云杉成熟林中的天山桦和天山柳只在小尺度(0～40m)上表现为聚集。随着天山云杉的生长,其聚集强度逐渐减小,聚集半径不断增大。从50a以下天山云杉到50～100a的天山云杉其聚集强度急速减小,这有利于天山云杉幼树获得足够的资源,是天山云杉幼树的一种生存策略或适应机制。150a以上天山云杉的聚集强度增加,这是由于天山云杉生长到150a左右时开始出现成熟后死亡,形成林窗有利于天山云杉林的更新。研究还对Ripley’s K系数法和频次检验法进行了比较,Ripley’s K系数法能够分析各种尺度下的种群空间格局,且不受样方大小的影响,结果清楚、直观。     

Spatial Distribution and Exploitation of Trees Gouged by Common Marmosets (Callithrix jacchus)

Resource distribution shapes many aspects of primate behavioral ecology. Though the spatial patterning of fruits, leaves, and insects has been explored among primate foods, comparatively less is known about exudate distributions. Tree exudates are a renewable resource, provide long-term evidence of exploitation, and may be selectively exploited to manipulate spatial distribution. We assessed the spatial patterning of trees gouged by common marmosets (Callithrix jacchus) to determine if they exhibit a uniform, random, or clumped distribution. We also asked whether marmosets selectively gouge trees in home range centers, which may afford them exclusive access to exudates. We explored whether spatial or physical characteristics of trees predict how intensely gouged trees were exploited. The mean nearest neighbor distance of gouged trees was significantly closer than expected for a random distribution and Ripley’s K-function showed that gouged trees were clumped across all spatial scales in our study area. Clumping may enable marmosets to reduce day and home ranges and facilitate repeated gouging of trees. Gouged trees were not closer to marmosets’ home range centers than peripheries, nor were centrally located trees more intensely gouged. Increased gouging intensity was associated with larger tree circumferences, although this effect was primarily driven by interspecific differences in circumference. Although marmosets may benefit from exploiting clumped exudates, they do not concentrate gouging in areas where they are more likely to gain exclusive access. Species-specific tree characteristics such as exudate quality and/or bark properties may play a larger role in determining gouging patterns than intergroup feeding competition.     

基于相邻木排列关系的混交度研究

混交度是反映森林群落中树种相互隔离状况的一个重要指标,目前已提出多种混交度指数.Mg考虑了对象木与最近相邻木的树种异同,Mv和Ms进一步考虑了最近相邻木(空间结构单元)树种数,但仍不能准确描述树种隔离程度.基于相邻木排列关系的混交度Mp,利用“1+4”结构的17个不同空间结构单元和天目山常绿阔叶林数据对Mg、Mv、Ms和Mp4个混交度进行了比较分析.结果表明:Mp的区分能力最强,Mv和Ms次之,Mg最差.Mp最适用于分析混交结构复杂的林分.在天目山常绿阔叶林分析中,混交度水平为中度,4个最近邻体中有2个相同种顺序排列的空间结构单元个数明显多于交错排列的个数.基于相邻木排列关系的混交度Mp能准确区分树种隔离程度,提高了混交度的区分度,可反映森林实际混交状况.     

Clumped planting arrangements improve seed production in a revegetated eucalypt woodland

The arrangement of plants within revegetated sites is rarely considered an important characteristic of these communities. However, in natural systems, plant spatial arrangements can influence a range of ecological processes, including pollination and seed set. Pollinators tend to preferentially visit larger and/or more closely spaced populations, with plants in these populations generally receiving more outcrossed pollen, resulting in increased seed set and better quality seed. Similar trends may occur in revegetated populations, but little is known about the influence of planting arrangement on seed production in restored systems. Here, we quantified the effect of plant abundance (number of conspecifics within 100 m) and distance to nearest reproductive conspecific on the level of seed set for six eucalypt species (n = 422 trees in total) in 1 year and for one of these species (Eucalyptus leucoxylon), across three additional years. Seed number per fruit was highly variable both between individuals and within individuals across years. Despite this variability, there was a consistent trend of higher seed production (seed number per fruit) when another reproductive conspecific was within 20 m. In contrast, plant abundance had little influence on seed production. Further investigation of nearest neighbor arrangements found the distance to either the first, second, third, or fourth reproductive neighbors were the key predictors of seed production. Therefore, revegetation designs that consider plant spacing and aggregation, rather than only planting to overall density criteria (i.e. trees/ha), at least for the eucalypts studied here, has the potential to improve seed production in revegetated populations.     

Inter‐individual variation in colour patterns in noctuid moths characterizes long‐distance dispersers and agricultural pests

A high capacity for long‐distance dispersal is a key to success for species confronted with environmental heterogeneity, habitat modification, fragmentation and loss. However, dispersal capacity is difficult to quantify and therefore poorly known in most taxa. Here, we report on a test for an association of variation in dispersal capacity with variable colouration of noctuid moths. First, using data from 12 experienced lepidopterologists, we showed that despite variation among experts in average assessments, different species are consistently classified as having non‐variable, variable or highly variable colour patterns when assessed by different experts. We then compared the incidence of non‐resident species with high inter‐individual variation in colour patterns recorded on the isolated island Utklippan (n = 47), with that in a species pool of potential long‐distance dispersers from the nearest mainland (n = 295). Species with high inter‐individual colour pattern variation were over‐represented on the island compared with species having non‐variable colouration. This finding constitutes rare evidence from the wild of long‐distance dispersal, measured on a spatial scale relevant for moths when tracking habitats in fragmented and changing landscapes or when keeping pace with environmental challenges associated with climate change. Finally, we showed that Swedish noctuid moths classified as agricultural pests (n = 28) had more variable colour patterns compared with non‐pests (n = 368). The majority of agricultural pests were also recorded on the isolated island, an outcome that is indicative of pest species having high dispersal capacity. Data on colour pattern variation may thus offer a simple and cost‐effective proxy to estimate dispersal capacity and can also help identify potential pest species. Our findings are potentially useful when modelling and predicting population and range dynamics of species in spatiotemporally heterogeneous environments, with direct implications for conservation biology and pest management.