scholarly journals Habitat alteration enables hybridisation between Lesser Spotted and Greater Spotted Eagles in north-east Poland

2013 ◽  
Vol 24 (2) ◽  
pp. 152-161 ◽  
Author(s):  
GRZEGORZ MACIOROWSKI ◽  
PAWEŁ MIRSKI
Keyword(s):  
Environmental Factors ◽  
Habitat Preferences ◽  
Arable Land ◽  
Habitat Requirements ◽  
Habitat Alteration ◽  
Landscape Changes ◽  
Human Settlements ◽  
North East ◽  
Conservation Implications ◽  
Several Variables

SummaryWetlands in the Biebrza Valley, north-east Poland, are inhabited by two closely related Aquila species: the more numerous Lesser Spotted Eagle A. pomarina prefers human-transformed landscapes, whereas the very rare Greater Spotted Eagle A. clanga is associated with natural marshy landscapes. At least since the last decade of the 20th century, these two species have been known to hybridise in the broad zone of their sympatric occurrence in Europe. The aim of the present study was to compare habitat preferences of both spotted eagle species in order to detect which environmental factors could increase the probability of hybridisation. We analysed nesting and hunting habitats for 148 breeding territories (61 of A. pomarina, 56 of A. clanga and 31 of mixed pairs). As expected, the presence of breeding Greater Spotted Eagles was associated with non-transformed marshy landscapes, whereas Lesser Spotted Eagles clearly preferred human-transformed areas. We hypothesised that mixed pairs should occur in intermediate habitat, confirming this assumption by analysing several variables: distance to human settlements, distance to open areas, and proportion of wetlands, shrublands, grasslands, agricultural mosaic and arable land. Results of this study suggest that some landscape changes can enable two species with different habitat requirements to inhabit the same area and hybridise. This scenario has potential conservation implications for the rarer species, Greater Spotted Eagle, which has narrower habitat preferences.

Habitat requirements and distribution of Engaeus cisternarius and three subspecies of Parastacoides tasmanicus (Decapoda : Parastacidae), burrowing crayfish from an area of south-western Tasmania

1980 ◽  
Vol 31 (4) ◽  
pp. 475 ◽  
Author(s):  
AMM Richardson ◽  
R Swain
Keyword(s):  
Small Area ◽  
Habitat Preferences ◽  
Sandy Soils ◽  
Taxonomic Status ◽  
River Valley ◽  
Habitat Requirements ◽  
Intensive Study ◽  
Extensive Survey ◽  
South West ◽  
Waterlogged Soils

During an extensive survey of the crayfish fauna of the lower catchments of the Gordon River, south-western Tasmania. two species of crayfish were collected: Engaeus cisternarius and three subspecies of Parastacoides tasmanicus (P. t. tasmanicus, P. t. inermis and P. t. insignis). From this survey and an intensive study in a small area of the Olga River valley, distinct habitat preferences of each of the forms were recognized. E. cisteinavius was restricted to the areas north and west of the Gordon River where it was found only in clay and sandy soils under rainforest. P. t. tasmanicus was found in waterlogged soils, peats and sands on valley floors covered either with wet sedgeland or rainforest. P. t. inermis was found in two disjunct habitats: well- drained slopes and hillsides covered in heath vegetation. and under rocks in small creeks in rainforests. P. t. insignis occupied an intermediate habitat between P. t. tasmanicus and the non-creek dwelling, P. t. inermis, but was restricted geographically to the extreme south-west of the study area. The taxonomic status of the P. tasmanicus subspecies is discussed.

scholarly journals Subterranean Species in Washington, D.C.: Spatial Analysis, Habitat Preferences, & Urban Conservation Implications

2018 ◽  
Vol 1 ◽  
Author(s):  
Jenna Keany
Keyword(s):  
Competitive Exclusion ◽  
Habitat Preferences ◽  
Shallow Groundwater ◽  
Soil Morphology ◽  
Chemical Parameters ◽  
Species List ◽  
Environmental Preferences ◽  
Small Water ◽  
Conservation Implications ◽  
Subterranean Species

Washington, D.C. is home to a remarkable assemblage of troglomorphic amphipods and isopods living in shallow groundwater habitats, the hypotelminorheic. Groundwater from the hypotelminorheic emerges on the surface into low-flowing seepage springs, or “seeps”, which are categorized as having blackened leaves, an underlain layer of clay, a drainage area of less than 10,000 m2, and are situated in slight topographical depressions. Stygobiotic species found in D.C.’s seeps include Crangonyx and Stygobromus amphipods and Caecidotea isopods. One species, Stygobromus hayi, is on the endangered species list and is endemic to the district; however, little is known about their habitat preferences or their distribution. All small water bodies, including rainwater puddles and seepage springs were sampled in national park lands in Southeast D.C. for hypotelminorheic fauna, soil morphology, and water quality indicators such as nitrates, phosphates, radon, pH, DO, and conductivity. Comparing sites with and without stygobionts, all phsysico-chemical parameters were statistically insignificant except for conductivity, which was able to distinguish between stygobiont-rich and stygobiont-poor seeps using logistic regression. Spatially, Crangonyx and Stygobromus amphipods rarely inhabit the same seepage spring, with only three occasions of cohabitation and an expected occurrence of ten. Caecidotea, however, is found in habitats with both amphipods. These results can be explained by either competitive exclusion or the presence of chemical differences in their habitats; however, even if there were some slight differences in their habitats, that still does not exclude competitive exclusion as an explanation. This study highlights new and important findings into the environmental preferences of D.C.’s most cryptic and rare species, and the importance of continued exploration of D.C.’s lesser known park lands.

Heterospecific social attraction in migrant birds: habitat niche overlap between two threatened shrikes

2019 ◽  
Vol 46 (1) ◽  
pp. 25 ◽  
Author(s):  
Gianpasquale Chiatante
Keyword(s):  
Niche Overlap ◽  
Indicator Kriging ◽  
Habitat Requirements ◽  
Distribution Models ◽  
Social Attraction ◽  
Conservation Implications ◽  
Habitat Niche ◽  
Lesser Grey Shrike ◽  
Migrant Birds ◽  
Grey Shrike

Context Effective biodiversity conservation requires information about a species’ ecology and its relationship with the geographical context. To achieve this efficiently, species distribution models can be developed, also taking into account species associations. Aims I aimed to illustrate the habitat requirements of two threatened passerines of semi-open landscapes, i.e. the lesser grey shrike, Lanius minor, and the woodchat shrike, Lanius senator, in southern Italy. Further, I assessed whether there is heterospecific social attraction between them, by assessing how their habitat niches overlap. Methods Data were collected by territory mapping during the 2009–13 breeding seasons. The habitat requirements of the species were investigated with the help of ecological niche factor analysis (ENFA). In addition, the areas of sympatry between the two species were defined by indicator kriging and the habitat niche overlap was analysed using the generalised linear model (GLM). Key results The results showed that these two species inhabit open areas, with scattered vegetation such as shrubs and trees, while avoiding intensively cultivated permanent crops, such as vineyards and olive groves. Moreover, a little difference was observed in the percentage cover of shrublands, which were higher in the woodchat shrike territories than in the lesser grey ones. The strong overlap in their habitat niches suggests heterospecific social attraction between them, especially because of the species rarity. Conclusions The lesser grey and the woodchat shrike were found to occur in very similar environments, by evidencing the overlap of their macrohabitat niches. This suggests the presence of heterospecific social attraction, corroborating the understudied hypothesis that this phenomenon is valid for migrant birds as well. The lesser grey shrike, in particular, may use occurrences of the woodchat shrike as a cue for assessing habitat quality and, thus, to establish its territory. Implications Considering the high habitat niche overlap, habitat changes occurring in the landscape might affect them equally. Furthermore, the use of heterospecific social information in habitat selection potentially has many important conservation implications. Indeed, by reproducing the appropriate information, birds could be attracted to specific sites known to be high-quality habitat.

scholarly journals Germination characteristics of Salicornia patula Duval-Jouve, S. emerici Duval-Jouve, and S. veneta Pign. et Lausi and their occurrence in Croatia

2013 ◽  
Vol 72 (2) ◽  
pp. 347-358 ◽  
Author(s):  
Nina Šajna ◽  
Marjana Regvar ◽  
Simona Kaligarič ◽  
Željko Škvorc ◽  
Mitja Kaligarič
Keyword(s):  
Environmental Factors ◽  
Habitat Preferences ◽  
Seed Morphology ◽  
Salicornia Europaea ◽  
Molecular Analyses ◽  
High Germination ◽  
Germination Characteristics ◽  
Salicornia Patula ◽  
Floral Characters

Abstract - According to recent molecular analyses of Salicornia, we revised the annual glassworts from the Croatian coast, classified until now only as Salicornia europaea. Two species, a diploid Salicornia patula and a tetraploid S. emerici were recognized. They can be easily distinguished by floral characters, but not only by their habitus, which varies extremely according to environmental factors. Both species differ also in seed morphology. Salicornia patula has dimorphic seeds, with larger central seeds reaching high germination rates. Germination patterns helped to explain the habitat preferences. The species rarely co-occur, however. The rare S. patula occupies drier habitats, on coastal mudflats or sands that are irregularly inundated. It occurs within the assoc. Suaedo maritimae-Salicornietum patulae. Salicornia emerici occupies the lowest coastal mudflats, regularly inundated, where nutrient-rich conditions prevail, and forms an almost monotypical assoc. Salicornietum emerici. Due to the synonymy of S. veneta with S. emerici, we exclude the occurrence of S. veneta in Croatia as an independent taxon.

Diversity, spatiotemporal distribution, abundance, species composition and habitat preferences of Ostracoda in Akbük and Akdeniz coastal mesosaline lagoons (Muğla, the South Aegean Region, Turkey)

2015 ◽  
Vol 44 (2) ◽  
Author(s):  
Selçuk Altınsaçlı ◽  
Ferda Perçin-Paçal ◽  
Songül Altınsaçlı
Keyword(s):  
Environmental Factors ◽  
Environmental Variables ◽  
Habitat Preferences ◽  
Aegean Region ◽  
Qualitative And Quantitative ◽  
Ordination Techniques ◽  
Ecological Importance ◽  
The Relationship ◽  
Ostracod Species

AbstractAkdeniz and Akbuk lagoons are part of a shallow coastal ecosystem of great aesthetic and ecological importance, located in Muğla Province in the southern Aegean region of Turkey. In the present study, four expeditions to collect ostracods from these lagoons were conducted in May, July, October, and November of 2008. Benthic samples were obtained monthly and several environmental factors were recorded simultaneously in situ. The ecological preferences of the ostracods were monitored, and qualitative and quantitative samples were collected from three sites in Akdeniz lagoon and two sites in Akbuk lagoon. Three ostracod taxa (Cyprideis torosa, Loxoconcha elliptica and Cytherois fischeri) were identified from the Akdeniz lagoon sampling sites and one species (Cyprideis torosa) from the Akbuk lagoon sampling sites. We present and analyze the dominance and distribution of ostracod assemblages and their relationships to environmental factors: temperature, dissolved oxygen, percentage oxygen saturation, pH, redox potential, salinity, and electrical conductivity) using classification and ordination techniques. Canonical correspondence analysis (CCA) is used to characterize the relationship between ostracods and the environmental variables. Approximately 82% of the correlation between the community composition and environmental variables was explained by the first axis of the CCA ordination for the Akdeniz lagoon. The study revealed that the distribution and population density of ostracod species depends on the physicochemical properties of the environment. The reason for this is that Cyprideis torosa and Loxoconcha elliptica are euryhaline species.

scholarly journals Assessing impacts of land abandonment on Mediterranean biodiversity using indicators based on bird and butterfly monitoring data

2015 ◽  
Vol 43 (1) ◽  
pp. 69-78 ◽  
Author(s):  
SERGI HERRANDO ◽  
LLUÍS BROTONS ◽  
MARC ANTON ◽  
FERRAN PÁRAMO ◽  
DANI VILLERO ◽  
...  
Keyword(s):  
Large Scale ◽  
Forest Cover ◽  
Habitat Preferences ◽  
Land Abandonment ◽  
Monitoring Data ◽  
Open Habitat ◽  
North East ◽  
The North ◽  
Butterfly Monitoring ◽  
The Impact

SUMMARYIn Europe, and particularly in the Mediterranean Basin, the abandonment of traditional land-use practices has been reported as one of the main causes of decline for open-habitat species. Data from large-scale bird and butterfly monitoring schemes in the north-east Iberian Peninsula were used to evaluate the impact that land abandonment has had on local biodiversity. Species’ habitat preferences, along a gradient from open to forest habitats, were significantly related to population trends: for both birds and butterflies, open-habitat species showed the most marked declines while forest species increased moderately. Multi-species indicators for tracking the impact of land abandonment on bird and butterfly populations were developed using habitat preference estimates and population trend indices. The patterns shown by these indicators were in line with the changes occurring in forest cover in the monitoring sites. This study reveals that multi-species indicators based on monitoring data from different taxonomic groups (here, birds and butterflies) may usefully be employed to track impacts of environmental change on biodiversity.

scholarly journals Monitoring of Landscape Transformations within Landscape Parks in Poland in the 21st century

2019 ◽  
Author(s):  
Piotr Krajewski
Keyword(s):  
Land Cover ◽  
Landscape Change ◽  
Arable Land ◽  
Landscape Changes ◽  
Nature Protection ◽  
Dominant Type ◽  
Mining Areas ◽  
The One ◽  
Landscape Transformations ◽  
Lower Silesia

One of the most problematic forms of nature protection in Poland relates to landscape parks. On the one hand, they include the most valuable landscapes; on the other hand, the areas within the landscape park still have economic uses. Therefore, the monitoring of landscape changes within landscape parks is necessary in order to properly manage these forms of protection. The main objective of the study was to monitor the scale and nature of landscape transformations within the boundaries of landscape parks in Poland during the period 2000–2018 and to assess the possibility of using the landscape change index (LCI) to monitor the intensity of landscape transformations within this type of protected area. Filling a gap in the research on landscape changes, I developed and verified the possibility of using LCI for monitoring the intensity of landscape changes using the example of 12 landscape parks in the Lower Silesia region. Preliminary analyses of the transformations within all landscape parks in Poland showed an upward trend, both in terms of the number of types of identified landscape changes as well as their area. In spite of the large diversity and degree of transformation in landscape parks, several dominant processes can be observed. The largest number and area of changes during each of the analyzed periods were found in transformations within forest landscapes (temporary and permanent deforestation and forest maturation), which constitute the dominant type of land cover within most of the landscape parks. In open landscapes, changes mainly relate to afforestation and natural succession in meadows, pastures and arable land, as well as the transformation of arable land into mining areas. Twelve case studies, covering all landscape parks of the Lower Silesia, have shown that the LCI is an excellent tool for monitoring the intensity of landscape changes, but it is dependent on the accuracy of the source data. The analyses confirmed that, during the study periods, the changes in all 12 Lower Silesian landscape parks were at a low level, but their particular intensification took place in the years 2012–2018. The highest LCI was found in the area where a natural disaster had occurred (air tornado), which destroyed huge areas of forest in landscape parks. After changes in the forest landscape, the most frequently identified type of change in 2006–2012 is the transformation of non-forest landscapes into forest landscapes. The main reason for such changes was the expansion of forest into abandoned arable land, meadows and pastures. The use of the Corine Land Cover database to calculate LCI and monitor the intensity of landscape change revealed a low usability of the database for the year 2000 and a high usability for data from 2006–2018.

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