scholarly journals Roads and Road-Posts as an Ecological Trap for Cavity Nesting Desert Birds

2020 ◽  
Vol 1 ◽  
Author(s):  
Nimrod Ben-Aharon ◽  
Dror Kapota ◽  
David Saltz

While road-side productivity attracts wildlife, roads are also a major cause of mortality. Thus, roads are potentially an attractive sink. We investigated whether roads in a desert environment in southern Israel act as an ecological trap for the territorial mourning wheatear (Oenanthe lugens). We applied an individual-based mechanistic approach to compare the apparent survival of individually-marked wheatears between roadside territories and territories in natural habitats farther away from the road, and determined directionality in territorial shifting to and from the road. Analysis was based on mark-resight techniques and multi-model inference in a multi-strata approach (program MARK). Wheatear survival in road-side territories was too low to be compensated by the maximum possible recruitment, but shifted territories from natural habitat toward the roadside habitat as these territories were vacated by mortality. Vacated territories along the road were re-occupied faster than vacated territories in natural habitat. Thus, the roadside habitat in our study area fulfilled all conditions for an ecological trap. Roads may act as widespread ecological traps and their impact, therefore, may extend well-beyond the existing perception of narrow dissecting elements causing local mortality and/or animal avoidance. In species where habitat selection is based on contest competition (e.g., territorial species) and contest success has a genetically heritable component, ecological traps will induce a paradoxical selection process.

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Cheng Gong ◽  
Liangtao Li ◽  
Jan C. Axmarcher ◽  
Zhenrong Yu ◽  
Yunhui Liu

AbstractIn the intensively farmed, homogenous agricultural landscape of the North China Plain, family graveyards form distinct cultural landscape features. In addition to their cultural value, these graveyards represent semi-natural habitat islands whose potential roles in biodiversity conservation and ecological functioning has remained poorly understood. In this study, we investigated plant species richness on 199 family graveyards of different ages and sizes. In accordance with biogeography theory, both overall and insect-pollinated plant species richness increased with area and age of graveyards. Even small graveyards show a strong potential for conserving local plant richness, and a mosaic of both large and small family graveyards could play an important role in the conservation of farmland biodiversity and related ecosystem functions. The launch of agri-environmental measures that conserve and create semi-natural habitats, in turn benefitting agricultural biodiversity and ecological functioning, has proven difficult in China due to the shortage of dispensable arable land. Given the great value of family graveyards as semi-natural habitats reflected in our study, we propose to focus preliminary efforts on conserving these landscape features as existing, widespread and culturally important semi-natural habitat islands. This would represent an effective, complementary policy to a subsequent re-establishment of other semi-natural habitats for the conservation of biodiversity and ecological functioning in agricultural landscapes.


2020 ◽  
Vol 86 (1) ◽  
pp. 133-152
Author(s):  
Matthew P. Purtill

To evaluate a model of the travel-route selection process for upper Ohio Valley Paleoindian foragers (13,500–11,400 cal BP), this study investigates archaeological data through the theoretical framework of landscape learning and risk-sensitive analysis. Following initial trail placement adjacent to a highly visible escarpment landform, Paleoindians adopted a risk-averse strategy to minimize travel outcome variability when wayfaring between Sandy Springs, a significant Ohio River Paleoindian site, and Upper Mercer–Vanport chert quarries of east-central Ohio. Although a least-cost analysis indicates an optimal route through the lower Scioto Valley, archaeological evidence for this path is lacking. Geomorphic and archaeological data further suggest that site absence in the lower Scioto Valley is not entirely due to sampling bias. Instead, evidence indicates that Paleoindians preferred travel within the Ohio Brush Creek–Baker's Fork valley despite its longer path distance through more rugged, constricted terrain. Potential travel through the lower Scioto Valley hypothesizes high outcome variability due to the stochastic nature of the late Pleistocene hydroregime. In this case, perceived outcome variability appears more influential in determining travel-route decisions among Paleoindians than direct efforts to reduce energy and time allocation.


1983 ◽  
Vol 31 (5) ◽  
pp. 695 ◽  
Author(s):  
IJ Rooke ◽  
SD Bradshaw ◽  
RA Langworthy

Total body water content (TBW) and TBW turnover were measured by means of tritiated water (HTO) in free-ranging populations of silvereyes, Zosterops lateralis, near Margaret River, W.A. Birds were studied in their natural habitats during spring and summer, and compared with a vineyard population in summer. In the natural habitat TBW content was found to be 77.6% in spring, which was not significantly different from that measured in summer (78.3%). Birds in vineyards in summer, however, were dehydrated, with a TBW content of 69.4%. Calculated rates of water influx for spring, summer and summer vineyards birds were 1.44,2.20 and 0.65 ml g.day-' respectively. These water turnover rates are much higher than those of any other bird yet studied. Dehydration was marked in the vineyard birds, with a significantly lower TBW content and an average net water loss of 0.63 ml day-'. Laboratory studies showed that silvereyes have a low tolerance to sodium loading. Their tolerance is, however, quite adequate for them to drink the most concentrated free water available to them in the field. Ingestion of concentrated sugar solutions of up to 25% did not provoke an osmotic diuresis and thus cannot account for the dehydration and negative water balance of vineyard birds.


2004 ◽  
Vol 82 (11) ◽  
pp. 1804-1817 ◽  
Author(s):  
Suzanne Prange ◽  
Stanley D Gehrt

Common raccoons (Procyon lotor (L., 1758)), Virginia opossums (Didelphis virginiana Kerr, 1792), and striped skunks (Mephitis mephitis (Schreber, 1776)) are common urban inhabitants, yet their relative demographic response to urbanization is unknown. Urbanization often affects community structure, and understanding these effects is essential in rapidly changing landscapes. We examined mesopredator-community structure in small and large patches of natural habitat surrounded by urban, suburban, or rural matrices. We created generalized logit models using road-survey and livetrapping data to examine effects of surrounding land use on proportions of opossums and skunks relative to raccoons, while accounting for effects of season and year and their interactions. For large sites, the land use × season model was chosen for both data sets, and occurrence of opossums and skunks relative to raccoons was higher at the rural site (P < 0.001 for all tests). For small sites, the land-use model best fit the road-survey data, with a higher occurrence of skunks relative to raccoons at the rural site (χ2 = 21.06, df = 1, P < 0.001). However, the season model best fit the trapping data for small sites. Our data indicated that raccoons exhibited a greater demographic response to urbanization, suggesting that they exploit anthropogenic resources more efficiently. Although numerous reasons exist for disparity in anthropogenic-resource use, differences in intraspecific tolerance and the role of learning in foraging behaviors were best supported by our observations.


2019 ◽  
Vol 77 ◽  
pp. 1-18
Author(s):  
Julien Carlier ◽  
James Moran

Across Europe, Greenways upcycle disused railway infrastructure into non-motorised public infrastructure, often with limited consideration to potential ecological synergies. Pre-development, disused transport corridors become relatively undisturbed and potentially host diverse semi-natural habitats. The study objectives were 1) to produce a highly detailed and accurate dataset using remote sensing with rapid assessment techniques for ground truthing and 2) subsequently examine habitat diversity existing along a proposed Greenway. A 7000 ha study corridor was based on a disused railway proposed as a transfrontier Greenway connecting the Republic of Ireland and the United Kingdom. The study applied a rapid-assessment virtual validation techniquealongside remote sensing and accuracy assessment. Inter-relationship between seminatural habitat diversity and land-use intensification was examined. Remote sensing accuracies of 89% and 99% for a real and linear habitat classification were obtained. Degrees of land-use intensification were observed throughout the corridor, highlighting the importance of maintaining and enhancing remaining semi-natural habitat that exists along the proposed Greenway route. Through understanding the landscape matrix composition and semi-natural habitat diversity, European Greenwayscan achieve multi-functionality for ecosystem conservation, forming integral components of Green Infrastructure.


2012 ◽  
Vol 10 (4) ◽  
pp. 75-96
Author(s):  
Piotr Matyjasiak

The aim of this paper is (i) to review the method of valorization of natural resources as applied in the environmental impact assessment, and (ii) to develop recommendations on how valorization expertise should be prepared in order to be comprehensive and transparent. Valorization is the proper time to carry out identi>cation of the possible negative environmental impacts and damages of a planned project. It is recommended to perform valorization due to the state (numbers) and functions (quality) of natural resources. This approach is related to the concept of environmental damage, which is defined as a measurable adverse change in a natural resource or measurable impairment of a natural resource service (which means the functions performed by a natural resource for the benefit of another natural resource or the public). Valorization of natural resources should include an assessment of potential environmental damage, including an impact on the local biodiversity, the ecological connectivity, the N2000 network, and the legally protected areas. The valorization of natural resources should be performed at the following thematic levels focusing on the role of the area under consideration due to: (1) the implementation of the objectives of protection of Nature 2000 network and its overall coherence, (2) the implementation of the objectives of protection of legally protected areas other than N2000, (3) the maintenance of the ecological connectivity in a context other than the coherence of Nature 2000 network, (4) the maintenance of species and natural habitats with favorable conservation status, (5) the conservation of species and natural habitat types that are not legally protected.


Author(s):  
Vladimir Grigor'ev ◽  
Dan Chuong Fam Thi ◽  
Rustam Nizamov ◽  
Igor' Grigor'ev

Aquaculture is one of the most promising and dynamically developing types of agricultural production, especially in countries with warm climates. The research was carried out to analyze the current situation in aquaculture in Vietnam to clarify the existing problems and prospects of this industry. When collecting materials, we used statistical data from the Government of the Socialist Republic of Vietnam, as well as information from representatives of the Institute of Economics and Business of the Vietnam National University (Hanoi). In the Socialist Republic of Vietnam, aquaculture is well developed and continues to actively expand, annually increasing the production of products that are in significant demand on the world market. One of the most important problems of the industry is the threat to natural biodiversity, primarily due to the reduction of the natural habitats of the inhabitants of rivers and mangroves. An equally important problem is the strong dependence of the production of products, primarily shrimp, on foreign markets, which today is objective and insurmountable. Due to the use of chemicals and antibiotics in aquaculture, especially in natural conditions, environmental degradation is possible. Among the promising areas for the development of the industry is the convergence of natural ecosystems and agriculture, a good example of which is the cultivation of shrimp in mangroves without destroying the forest cover. It is possible to switch to aquaculture as an adaptation to changes in the ecological situation, primarily to the salinization of river deltas. As a result of a decrease in the profitability of fishing in the natural habitat of fish and shrimps, an increase in their populations in natural conditions is possible


2021 ◽  
Vol 12 ◽  
Author(s):  
Zhaoying Zeng ◽  
Dan Mou ◽  
Li Luo ◽  
Wenlin Zhong ◽  
Lin Duan ◽  
...  

Cordyceps cicadae is an entomogenous fungus with important uses in traditional Chinese medicine. However, its wild resources have not met consumers’ demand due to excessive harvesting practices. Artificial cultivation is therefore an important alternative, but research on cultivating C. cicadae in natural habitats has not been reported. In this study, we aimed to explore the viability of cultivating C. cicadae in a natural habitat, in the soil of Pinus massoniana forest. We assessed and compared the yield, metabolite contents and bacterial community composition of C. cicadae grown in the Antheraea pernyi pupae at different growth stages, and under different cultivation conditions, in the soil of a natural habitat and in sterile glass bottles. Our results showed that cultivating C. cicadae in a natural habitat is feasible, with up to 95% of pupae producing C. cicadae fruiting bodies. The content of nitrogen compounds (amino acids) in C. cicadae cultivated in a natural habitat was significantly higher than in glass bottles, while the yield and carbon compound (mannitol and polysaccharide) and nucleoside (cordycepin and adenosine) contents were lower. Different bacterial genera were enriched in C. cicadae at different growth stages and cultivation environments, and these bacterial genera were closely related to metabolites contents during growth. This study demonstrated the viability of a novel cultivation method of C. cicadae, which could be used as an alternative to wild stocks of this fungus. These findings provided new insights into the growth mechanism of C. cicadae and its interaction with soil microorganisms.


2018 ◽  
Author(s):  
Miguel Á. Collado ◽  
Daniel Sol ◽  
Ignasi Bartomeus

ABSTRACTHabitat loss and alteration is widely considered one of the main drivers of the current loss of pollinator diversity. Unfortunately, we still lack a comprehensive analysis of habitat importance, use and preference for major groups of pollinators. Here, we address this gap analysing a large dataset of 15,762 bee specimens (more than 400 species) across northeast USA. We found that natural habitats sustain the highest bee diversity, with many species strongly depending on such habitats. By characterizing habitat use and preference for the 45 most abundant species, we also show that many bee species can use human-altered habitats despite exhibiting strong and clear preferences for forested habitats. However, only a few species appear to do well when the habitat has been drastically modified. We conclude that although altered environments may harbor a substantial number of species, preserving natural areas is still essential to guarantee the conservation of bee biodiversity.


Author(s):  
Erle C. Ellis

Human reshaping of ecology has been driving the Anthropocene transition since its very first beginnings. ‘Oikos’ explains that the Anthropocene poses even greater challenges for those working to conserve and restore natural habitats. What does ‘natural habitat’ even mean on a planet transformed by humans? The complex dynamics of human–environment interactions make it a challenge to detect whether a significant ecological change has occurred. The ‘historic range of variability’ or ‘baseline’ state of ecological parameters needs to be characterized. If human societies are now operating as a global force that is transforming Earth to the detriment of both humanity and non-human nature, what, if anything, is to be done about it?


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