Roadside Habitats Research Articles

Effects of road features on the phytogeographical characteristics of plant species on natural-area roadsides

Road features can affect the species distribution along road verges; however, we do not know much about their significance. This research was intended to assess the importance of some road features including age, traffic, width and side slope in determining the species composition and chorotype distribution along natural area roadsides. Sampling was performed by a stratified random method, so 38 sites by twelve asphalt roads were sampled within 100-m2 plots. Canonical correspondence and redundancy analyses were conducted to describe the correlation of road features and elevation with species distribution and chorotypes along roadsides. The results showed that the road age and traffic volume were the important road features determining chorotype composition along the rangeland roadsides. Although elevation explained some variation in chorotype data, it had a lower effect than the road age. However, elevation was the most important variable in species distribution along the roadside habitats. Road age, road width, traffic volume and roadside slope were the other important variables in species distribution along the natural-area roadsides. The response curve of chorotypes to the road age and traffic volume showed that medium-aged roads and medium traffic volume provided optimum conditions for the native uni-regional chorotype. Medium-aged roads also provided optimum conditions for some bi-regional and pluriregional chorotypes. In conclusion, road features such as age and traffic volume play an independent and more important role in chorotype distribution along the natural area roadsides, compared to elevation.

Integrating large mammal behaviour and traffic flow to determine traversability of roads with heterogeneous traffic on a Central Indian Highway

Roads impact wildlife in multiple ways, most conspicuous amongst which are animal-vehicle collisions (AVCs). Mitigation measures to reduce AVCs at the local scale are often centred on species-specific crossing zones and collision hotspots. However, at the road network scale, consideration of interactions among road, species and traffic characteristics influencing AVC occurrence is required to design effective mitigation strategies. We modelled traversability—the probability of an animal successfully crossing a road- across an Indian highway for six large mammal species under different scenarios of road and traffic characteristics. Among the study species, group-living and slow-moving animals had higher AVC probabilities that increased significantly with increasing traffic volume and proportions of heavy vehicles in the traffic flow. The risk of AVC was higher for species that were active near roadside habitat during peak traffic hours. Our approach could help identify roads that pose potential mortality risks to animals using empirical data on animal and traffic characteristics. Results suggest that regulating traffic volume and heterogeneity on existing road stretches could potentially reduce animal mortality and barrier effect. Mitigation on roads expected to carry heavy traffic loads passing through ecologically-sensitive areas should be prioritised to ensure traversability for animal communities.

Road network forms specific stations for living organisms in the conditions of the steppe zone

The state of art analysis of available published data allowed to determine the features of the roadside ecosystems formation and the possibility of further development of biodiversity conservation measures. In Ukraine and around the world, road infrastructure is an important economic and social object that has a negative impact on the environment. This takes place due to environmental pollution, fragmentation of habitats, biodiversity loss, etc. At the same time, on the roadsides the stations (microhabitats) are being formed. They can be a barrier to motor vehicle pollution and provide available shelters for living organisms. Road operation usually affects the structure of roadside vegetation. There is an increase in the number of of annual plant species and a decrease in perennials. Favourable conditions are also created for the spread of heliophytes and xerophytes. Roads are a source of chemical pollution that affects all components of roadside ecosystems. The amount of pollutants is mainly dependent on the traffic intensity and road width. The creation of roadside forest plantations significantly reduces the negative impact of vehicles. Wood plantations contribute to better carbon deposition, which is an integral part of many vehicle pollutants, and create a barrier for pollutants coming far from roads. Forest belt can also be a refuge for many species of animals and combine fragmented habitats around. Because plants and small animals at roadside stations are bound to their localities, they are able to accumulate much amount of ecotoxicants, especially heavy metals, which should be taken into account when conducting local business. For the living of animals in roadside stations, the characteristics of specific confined plant community, microclimate and landform are quite important. Due to the linearity and long distances, roadsides provide migration ways for many species. The developed roadside habitats may be the refugia for not only common, but for rare animals. We should conclude that further research of the environmental benefits of roadside ecosystems in the Steppe zone of Ukraine would allow developing effective measures for roadside management in the frames of nature conservation.

Foraging behavior of Purple-rumped sunbird (<i>Leptocoma zeylonica</i>) and Long-billed sunbird (<i>Cinnyris lotenius</i>) in selected habitats in Kandy district, Sri Lanka

Sunbirds (Passeriformes: Nectariniidae) are small passerines that feed largely on nectar. The aim of this work was to study the occurrence of sunbirds in different habitats, to observe and describe their activity frequencies, to observe the relationship of the Long-billed sunbird Cinnyris lotenius and Purple-rumped sunbird Leptocoma zeylonica with their host flowers, and to examine their behavioral relationships with the colour of the flower, flower count, nectar glucose concentration and the length of corolla of flowers. The study was carried out in five different habitat types in the Kandy district, Sri Lanka: a forest reserve, home garden habitats at two widely separated locations, a roadside habitat, and a botanical garden. The study was carried out between March and September 2013. Results show that during the day, sunbirds spent most of their time in foraging than in acquiring food. In the study, 21 different plants were recognized as nectar feeding plants for sunbirds. The number of visits by sunbirds did not depend on the plant species or the colour of the flower. The results also indicated that the correlation between the flower count and the occurrence of the Long-billed sunbird was not significant. However, there was a significant correlation between the flower count and the occurrence of the Purple-rumped sunbird. Furthermore, there was a significant correlation with the glucose concentration and the occurrence of the Long-billed sunbird; whereas no such correlation between the glucose concentration and the occurrence of Purple-rumped sunbird. There was no significant correlation with the length of corolla and the occurrence of the Long-billed sunbird, but there was a significant correlation in occurrence of Purple-rumped sunbird and the length of corolla. These correlations are due to the difference in their body size and bill length. The difference in feeding plants is due to their bill length and that allows both of them to share a common habitat.

Motorway age is linked to larger body size, but not song carrier frequency, in male grasshoppers from roadside populations

Producing calls with increased minimum carrier frequency is well documented in sound communicating species confronted with noise pollution, possibly helping them to avoid acoustic masking of low-frequency signals. However, the lack of studies on invertebrates limits our understanding of the potentially adverse effects of anthropogenic noise on natural populations. While males of the grasshopper Chorthippus biguttulus are known to produce courtship signals with elevated low-frequency local maxima (LFLM) in roadside populations, previous studies provided no insight into morphological traits underlying LFLM shifts. Although developmental plasticity was identified as one main factor accounting for elevated LFLM, an additional role for a more hard-wired trait architecture was proposed, possibly as a result of adaptation to traffic noise. Our current study therefore aims to assess (1) whether the position of LFLM is related to male body size, (2) whether body size is correlated with motorway age, and (3) whether the position of LFLM is correlated with motorway age in C. biguttulus males from roadside populations. In addition to substantial variation in LFLM among C. biguttulus males, we found that larger males produced signals with lower LFLM, suggesting a potential role in female choice as a predictor of male quality. While we found no significant correlation between LFLM and motorway age, C. biguttulus males were larger near older motorway sections. This positive correlation may be due to several reasons, including: (1) higher nutrient concentration and availability in plant tissues due to eutrophication of roadside habitats; (2) temporal succession of male size phenotypes during colonization processes; and/or (3) selection for larger body size in roadside populations. Our results highlight the multifaceted and often complex nature of the relationships between morphology, signal traits and anthropogenic pressures on sound communication in invertebrates.

Cougar roadside habitat selection: Incorporating topography and traffic

Cougar roadside habitat selection: Incorporating topography and traffic

Traffic influences nutritional quality of roadside plants for monarch caterpillars

Roadside habitats are increasingly being targeted for restoration and conservation. Roadside habitats often exhibit altered soil and plant chemistry due to pollution from maintenance (e.g. de-icing salt), car deterioration, and exhaust. Roadside plants may attract animals due to elevated levels of sodium or nitrogen, but high concentrations of heavy metals and sodium can be toxic, potentially setting an ecological trap. In this study, we determine how roads influence the chemistry of common milkweed (Asclepias syriaca) as it is the primary roadside host plant for the declining monarch butterfly (Danaus plexippus) in the eastern United States. Even though road salt is applied during the winter, we detect enhanced sodium along roads the following growing season. Road salts increase soil sodium, which in turn elevates host-plant foliar sodium (occasionally to toxic levels in <10% of plants) and sodium content in monarch caterpillars feeding on these plants. Sodium levels of milkweed leaves are highest close to the edge of busy roads. Some heavy metals (lead, zinc) are also elevated in roadside soils or plants. Nitrogen content was affected by adjacent agricultural use, but not traffic volume or proximity to a road. Other potential road pollutants (e.g. nickel) were not elevated in soil or plants. Despite a clear signature of road pollution in the chemistry of milkweed, most plants are likely still suitable for developing monarchs. Nonetheless, restoration investments in snowy regions should prioritize sites with lower-traffic density that are further from the road edge to minimize toxic impacts of high sodium. To extend this research to other insects of conservation concern, future work should characterize the nutritional quality of nectar, pollen, and other species of host-plants in roadside habitats.

Assessing zinc tolerance in two butterfly species: consequences for conservation in polluted environments

Abstract Zinc is a widespread pollutant released from industrial combustion, automobile residue, and mining. Zinc accumulates in soils and mobilises into plant tissue where it may be consumed to potentially toxic levels by leaf feeding insects, including developing pollinators. While zinc tolerance thresholds have been previously assessed in insect pollinators, most observations are limited to model organisms and pest species. We lack understanding of zinc tolerance in insects of conservation concern. We assess dietary zinc tolerance of developing caterpillars from wild populations of the monarch butterfly (Danaus plexippus), a species of conservation concern, whose caterpillars are commonly exposed to elevated dietary zinc exposure in milkweed plants along roadsides. We contrast monarch zinc tolerance with that of cabbage white butterfly caterpillars (Pieris rapae), a non‐native pest species. Tolerance was assessed by rearing caterpillars on artificial diets containing varying levels of zinc. Zinc reduced monarch survival at levels as low as 344 mg kg−1 but positively impacted cabbage white survival at 227 and 738 mg kg−1. Cabbage whites also displayed prolonged development time, smaller adult body size, and slower growth rate, consistent with the possibility that zinc tolerance had fitness costs. Our results support previous observations that heavy metal tolerance varies between species and highlight the importance of broadening our understanding of tolerance to insect species of conservation concern before drawing general conclusions about insect susceptibility to heavy metal pollution. Nonetheless, our results suggest that zinc pollution alone is unlikely a risk in developing roadside habitat for monarch butterflies.

Effect of pan trap size on the diversity of sampled bees and abundance of bycatch

Monitoring pollinator health and pollination is among the top priorities to safeguard pollinators and secure pollinator services. Assessments of sampling methods are therefore essential for developing a standardized protocol for long-term pollinator monitoring. Pan trapping is a popular technique to survey pollinators, but limited information is available on the effect of pan trap diameter on the abundance, richness, and body size of sampled bees, as well as on the abundance of bycatch (non-targeted arthropods). We conducted experiments using four diameters of yellow pan traps in three habitats (a semi-natural phrygana habitat, a roadside, and a salt flat) on the Greek island of Lesvos during a 10-day period in late June/early July of 2017 and 2018. We found that pan traps of 4, 7, 10, and 12 cm captured a similar richness of bees and have little or no effect on the abundance estimates of bees and flies. Pan trap diameter did not affect body size of collected bees. Bycatch accounted for 62.8% of the arthropods collected and increased with the diameter of the pan traps in the phrygana and roadside habitats. According to literature, many researchers, especially outside Europe, use pan traps of various diameters (7–34 cm), volumes (96.1–2000 ml), and shapes (round, square, rectangular, or hexagonal). To reduce potential negative effects on populations of other beneficial arthropods, as well as to minimize processing effort and costs, we recommend using small pan traps (7 cm), unless standardized pan trapping protocols have already been adopted.

Evaluating the effects of roads on giant panda habitat at two scales in a typical nature reserve

Little is known about how roads affect the habitats of giant pandas (Ailuropoda melanoleuca), this study aimed to provide a scientific basis to better understand this question, and to formulate targeted measures to reduce the adverse effects of roads. To evaluate the effects of roads on giant panda habitat, a field survey was carried out in the Wanglang Nature Reserve at two scales, 400 m2 and 100 m2, in July and August of every year from 2015 to 2019. We compared the community characteristics of roadside habitats, giant panda habitats and the local environment by using difference tests and multiple comparison methods. The results showed that, at the 400 m2 scale, the significant differences in number of bamboo clumps and regeneration size among different habitats were related to roads. At the 100 m2 scale, the significant difference in number of bamboo clumps was also related to roads. Roads may affect the number of bamboo clumps and regeneration size, which alters important characteristics of giant panda habitat. The roadside habitat had fewer bamboo clumps and smaller regeneration sizes than the giant panda habitat, and this lack of food may be why giant pandas seldom use the roadside habitat. To improve the suitability of the roadside habitats, more bamboo should be planted and protective measures should be taken to ensure the normal growth of bamboo and regeneration species. This study provides reference methods for future studies on the effects of roads in other regions.

Responses in Phenotypic Plasticity of Amaranthus palmeri and Polygonum orientale to Soil Factors under Different Habitats

AbstractThe extension and structure of functional traits variation in response to different soil factors between invasive and native plants are poorly understood. Functional traits and soil factors of the invasive plant Amaranthus palmeri and its coexisting plant Polygonum orientale are investigated under three heterogeneous habitats: roadside (rs), wasteland (wl), and riverbank (rb) in Tianjin, China. The shoot dry weight (SDW) and leaf nitrogen (LN) of A. palmeri are significantly higher compared with P. orientale, while A. palmeri has significantly lower leaf dry weight (LDW), leaf area (LA), leaf carbon (LC), and leaf C/N ratio under different habitats. The larger phenotypic plasticity of A. palmeri is one of the important reasons for their successful invasion to heterogeneous habitats. Similarly, the soil water content (SWC) of both species shows a significant difference (p &lt; 0.05) with maximum in riverbank habitat to lowest in roadside habitat. Soil N/P ratio, C/N ratio, and C/P ratio of rb habitats are significantly lower compared to wl and rs habitats (p &lt; 0.05). A redundancy analysis indicates that SWC is the dominant soil factor affecting the functional traits of A. palmeri and P. orientale. However, A. palmeri forms an environmental adaptation strategy by changing traits of SDW, LN, and leaf C/N ratio, which is different from P. orientale by changing traits of LA and LDW.

Roadside Habitats: The Impact of Salinization on the Occurrence, Growth and Reproduction of Two Weed Species Echinochloa crus-galli and Digitaria sanguinalis

The specific conditions in habitats in the immediate vicinity of roads provide a suitable environment for noxious weeds and invasive species that spread through them to the landscape. Echinochloa crus-galli and Digitaria sanguinalis are problematic weeds of wide-row crops. The field experiment focused on the impact of the roadside habitat salinization on the occurrence, growth and reproduction of these two species. Quantitative vegetative and generative characteristics of the plants were determined. Measurements were carried out at three distances from the edge of the road and on control plots. The results showed that the growth and reproduction of E. crus-galli and D. sanguinalis occur in the period when the values of soil environmental variables correspond to values of non-saline soil according to the criteria for soil salinity assessment. Despite this fact, the average salinity of soil along roadside was still higher than in soil of further distances and we found these levels of salinity to be well tolerated by the study species. Therefore, we conclude that roadsides with the same or higher salt content represent a suitable location for the occurrence and reproduction of E. crus-galli and D. sanguinalis, thus being temporary locations that enable their further spreading to the countryside.

Ant (Hymenoptera: Formicidae) Fauna of the Marine Port of Savannah, Garden City, Georgia (USA)

Abstract Seaports act as a critical interface between land and sea for the international transportation of goods and have played an important role in the introduction of exotic ant species worldwide. The objective of our survey was to catalog the ant species residing on and immediately adjacent to the Port of Savannah in Garden City, Georgia, USA. We assessed the ant fauna with pitfall traps, baits, active searching on trees, extraction from leaf litter, and destruction of coarse woody debris (rotting logs) along nine transects in wooded areas. We also collected ants along roadside habitat on and adjacent to Port of Savannah property. In total, we collected 1,300 samples in 2015 and 2016. Forty-five ant species representing 20 genera were cataloged, including 13 exotic species from 10 genera; 65,424 ants were collected during the study. The most diverse genera were Strumigenys (six species); Crematogaster and Pheidole (five species each); and Camponotus and Solenopsis (four species each). The tawny crazy ant, Nylanderia fulva Mayr, which was the most common ant collected (76% of all ants collected along nine transects in wooded areas), is reported here for the first time in Chatham County, Georgia and is the northernmost location from which it has been reported. Owing to the ubiquitous nature of the Formicidae, one or more ant species were present in 97.7% of the study's 1,300 samples.

Vegetation Ecology Associated with Some Species of Family Zygophyllaceae in Different Regions of Egyptian Desert

The Zygophyllaceae is a widespread family of common existence in arid and semi-arid habitats of the Old and New Worlds, especially in seasonally dry deserts. Various members of this family are characterized by high efficient potential for the treatment of broad spectrum health disorders and well known in scientific and folk literature for their medicinal uses. TWINSPAN cluster for the 38 stands yielded four vegetation groups (A, B, C and D) at the 3rd level of classification. These groups were identified after the first dominant species that attained the highest importance value (IV). Group A: Zygophyllum aegyptium, group B: Fagonia cretica, group C: Zygophyllum coccineum and group D: Pulicaria undulata. The vegetation group A characterized sand formation habitats along Deltaic Mediterranean coastal desert, while group B represented roadside habitats of the western Mediterranean coastal desert, group C dominated Wadi Hagul bed and gravel desert habitats of Suez. Furthermore, group D inhabited wadi bed and roadside habitats in Ismailia. Ordination of the vegetation groups along 2 axes was performed using Detrended Correspondence Analysis (DCA), while Canonical Correspondence Analysis (CCA) was utilized to determine the relation between the community types and soil factors.

Butterflies do not alter oviposition or larval foraging in response to anthropogenic increases in sodium

Humans have drastically increased the availability of many once-limited nutrients, resulting in potential attraction of animals to now toxic, novel nutritional conditions. For instance, herbivores are attracted to sodium in many terrestrial ecosystems because sodium occurs in much lower concentrations in plants than in animals. However, sodium availability has increased due to crop irrigation or distribution of de-icing salts along roads. While moderate increases in once-limited sodium may be beneficial, large increases are potentially toxic. Here, we investigate whether increased sodium along roadsides is functioning as an ecological trap, drawing butterflies to oviposit and forage on plants with toxic levels of sodium. As in many other animals, butterflies exhibit sodium-specific foraging behaviour – males will ‘puddle’ for minerals on mud, dung or carrion; yet sodium-seeking behaviours at other life stages remain unexplored. We present data from a series of field- and laboratory-based sodium preference trials using both caterpillars and ovipositing adult females. Female monarch and cabbage white butterflies did not show any preference for laying eggs on sodium-enriched plants, either at moderate levels that are likely to be physiologically beneficial, or at potentially toxic levels typical of high-traffic roads. Monarch caterpillars somewhat avoided the plants highest in sodium, but this behaviour is unlikely to compensate for the failure of ovipositing females to avoid toxic high-sodium plants. These results suggest that while butterflies frequently use sodium-enriched roadside habitats, they are unlikely to be seeking out or avoiding these areas due to elevated sodium.

Monarch butterfly host plant (milkweed Asclepias spp.) abundance varies by habitat type across 98 prairies

The decline in migratory monarch butterflies (Danaus plexippus) over the past 20 years has been attributed to several drivers, including loss of their host plants (milkweeds Asclepias spp.). This has sparked widespread interest in milkweed ecology and restoration. We developed a model on environmental and habitat‐type variables to predict milkweed abundance by sampling 93 prairie plantings (47 conservation plantings and 46 roadsides) and 5 unplowed prairie remnants throughout the state of Iowa, United States. Milkweeds were censused in 10–25 random locations within each site, and data on plant diversity, age of planting, soil characteristics, and management were tested as predictors of abundance. Milkweed densities of all species combined were highest in remnant prairies (8,705 stems/ha), intermediate in roadside plantings (1,274 stems/ha), and lowest in conservation plantings (212 stems/ha). Most milkweeds were common milkweeds Asclepias syriaca, which were more abundant in roadside than conservation plantings. Remnants contained the most milkweed species. Total milkweed and common milkweed abundance were both predicted by higher soil pH, a more linear site shape, and lower soil bulk density across restorations. Our results indicate that common milkweed is maintained by disturbance, and establishes readily in rural roadside habitat. Remnants are important as reservoirs for multiple milkweed species and should be protected.

Road mortality of freshwater turtles in Palawan, Philippines

The impact of road mortality on freshwater turtle populations on a global scale could be significant enough to cause the extinction of sensitive species. Essential data on roadkill abundance, composition, spatial patterns, and temporal distribution is needed for crafting mitigation strategies. To provide such information, a survey was conducted along the highway section (67 km) connecting Aborlan and Puerto Princesa City in Palawan, Philippines. Collection of data was done four times a month from January 2010 to December 2015. A total of 127 road-killed turtles belonging to two species of the Geoemydidae family were recorded, 102 (80.3%) of which were classified as the Southeast Asian Box Turtle (Cuora amboinensis) and 25 (19.7%) were identified as the Asian Leaf Turtle (Cyclemys dentata). The increase in road traffic noticed during the survey period possibly caused the corresponding increase in the roadkill counts of C. amboinensis, which is a more common species. Concurrently, the decline in the road-kill counts of C. dentata may indicate a severe drop in the population of this less common species. Roadside habitat types, time of the day, and presence of water bodies are found to be important predictors of road-killed turtles. High densities of road-killed turtles clustered in short segments of the road which identified as hotspots. Effective mitigating measures to curve down the impact of road mortality on turtle populations must be implemented and focusing the conservation strategies along the hotspots is considered an efficient and practical option.

Influence of motor transport on species composition and number of roadside habitat carabid beetles

This paper examines the impact of road transport on species composition and abundance of roadside habitat carabid beetles. The studies were carried out in Saransk and its suburban area, because it is cities that are most affected by anthropogenic press, as they evolved and exist in concentrated and intensive impact of human society. When analyzing urban fauna one can get objective information about how harmful pollution of air, soil, water, plants to organisms, how effective those or other environmental measures, what dynamics of ecological situation is in the city. The study of carabid fauna in these circumstances, is оf great interest, as it allоws to find measures to restore damaged ecosystems and to track the dynamics of changes in the implementation of these measures.

Patterns in urban butterflies and spontaneous plants across a University campus in Japan

University campuses often contain contiguous areas of urban green space (UGS) which are otherwise scarce in large cities and, thus, may provide critical habitat for numerous species. In this study, we evaluate butterfly and plant diversity at Chiba University in Japan from five UGS types, including intensive green roofs, meadows, roadsides, open spaces, and community gardens. Surveying non-destructively every two weeks from June to November 2010, we identified 707 individual butterflies to 25 species from five families, including red-listed species (e.g. Parantica sita Kollar, 1844). However, one species, Pseudozizeeria maha Kollar, 1848, represented over 50% of all individuals surveyed. Butterflies in the family Papilionidae showed strong preference for roadside habitat, indicating the importance of ‘butterfly flyways’ and contiguous habitat corridors on University campuses. Butterfly richness and abundance was significantly different between UGS types and highest in the community garden and roadsides. We recorded 70 garden plant species and 117 spontaneous plant species (which grew opportunistically, without design input), of which 58% were native. Total plant richness was positively correlated with butterfly species richness, and non-native spontaneous plant species richness was positively correlated with butterfly richness, abundance, diversity, and evenness. Additionally, 76% of the spontaneous species identified were determined to be used by butterflies as larval hosts or for adult feeding. Identification of spontaneous plant species and use of selective weeding should be included in landscape management planning on campuses to promote butterflies, which can act as ambassadors for biodiversity conservation and help connect people to nature.

The secret life of possums: data loggers reveal the movement ecology of an arboreal mammal

Understanding animal movement patterns is fundamental to ecology, as it allows inference about species' habitat preferences and their niches. Such knowledge also underpins our ability to predict how animals may respond to environmental change, including habitat loss and modification. Data-logging devices such as GPS trackers and accelerometers are rapidly becoming cheaper and smaller, allowing movement at fine scales to be recorded on a broad range of animal species. We examined movement patterns of an arboreal mammal (bobuck, Trichosurus cunninghami) in a highly fragmented forest ecosystem. The GPS data showed males travelled greater distances than females in linear roadside strip habitats, but not in forest fragments. The accelerometer data showed that both sexes exhibited higher activity levels in roadside habitats compared to forest fragments. By coupling GPS and accelerometer data, we uncovered for this species an ecological pattern similar to other mammals: that male bobucks had higher activity levels than females for a given distance travelled. Our findings also suggest that habitat fragmentation changes the amount and type of activity bobucks perform while moving, and that linear forest strips could be considered “energetically challenging” habitats, which informs how we should manage the spatial distribution of key supplementary resources for this species such as nest sites and minimum fragment sizes.