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1.
Capsule: Hooded Crows Corvus cornix selected nesting trees based on species, height, grouping and distance from an occupied house. Nest re-use was common and pairs that re-used old nests produced more fledglings than those that built a new nest.Aims: To determine the features of trees that influenced whether they were used by Hooded Crows as nest sites, to establish what factors influenced nest re-use between years and to explore potential costs or benefits of nest re-use.Methods: In a large area of Orkney, Scotland, the features of trees that contained a Hooded Crow nest were compared to those of trees where nests were absent. Patterns of nest re-use between years were examined in relation to the availability of alternative sites, previous nesting success and the number of equivalent options to the tree used previously within 200?m of this site.Results: Hooded Crows favoured spruce and pine trees as nest sites, above the most locally abundant tree species, elder and willow. Preference for trees increased with tree height, local tree density and distance from occupied houses. Over half of the crows studied re-used an old nest when one was available and crows that re-used an old nest fledged more offspring than those that built a new nest. The likelihood of a new nest being built increased as the number of potential locations to build increased. Territories where a nest survived the winter were more likely to be reoccupied the following year than those where nests fell, while territories with fewer trees around the old site were most likely to be abandoned, suggesting that those were territories of lower quality.Conclusions: Hooded Crows displayed strong preferences for nest sites that might favour nesting success by offering concealment, shelter and protection from ground-based predators. Nest re-use was common, especially when alternative sites were scarce, and appeared to facilitate greater reproductive output. 相似文献
2.
Mark J. Whittingham Ailsa J. McKenzie David Feige Tom Cadwallender Matthew Grainger 《Bird Study》2020,67(2):264-267
ABSTRACT In this reply, we confirm that the results of the original paper are robust and that our conclusions were correct: densities of Ruddy Turnstones Arenaria interpres were lower on sites located further from undisturbed refuges. There are two points of learning here: (i) taking the findings of a paper based purely on what is published is normal but there is an unpublished iterative process for analysis that is often hidden from a reader (described here), so we refute that our results were caused by chance; (ii) we published a result based on an incorrect method in the revision process. We hope that other researchers involved in long-term projects involving large and complex datasets can learn from our mistake, as we will endeavour to do. 相似文献
3.
《Bird Study》2012,59(3):398-406
ABSTRACTCapsule: In large and medium wetlands with extended reed beds Phragmites and cattail Typha dominated areas, Water Rails Rallus aquaticus and Little Crakes Zapornia parva show higher differences in nesting sites in contrast with other populations from small and fragmented wetlands, where the ranges of values for environmental variables at nesting sites overlap greatly.Aims: To investigate the nesting sites and nesting habitats of both species to a fine scale, on medium and large wetlands, to evaluate the potential overlapping of nesting habitat and to compare data with those obtained in small wetlands.Methods: In the study area, the Fize? Basin, Romania, 17 wetlands, ponds and reed beds ranging from 11.78 to 252.68 ha were investigated. The species were present on 4 wetlands, which were subsequently surveyed for nests. Between April and August 2010–2012, a total of 83 Water Rail and 46 Little Crake nests were found, measured and analysed in terms of nesting habitat and nest features.Results: Principal component analyses suggest no overlap in nest site selection and a partial overlap in the nest features. An analysis of similarity confirmed significant nest structural differences. A discriminant function analysis highlights the main factors dividing the nest features of both species being: water depth and distance between the nest and a water surface. Little Crakes build their nests in cattail Typha sloped clumps, while Water Rails build their nests near reed Phragmites strains.Conclusion: In large and medium wetlands, Water Rails nest deep in the reed bed rather than in other types of habitats, contrary to what has been reported for small ponds areas. Little Crakes nest in cattail independently of the size of the wetland where they occur. 相似文献
4.
F. Henrioux 《Bird Study》2013,60(3):250-257
Capsules Sites are selected as part of an antipredator strategy. Aims To assess if site choice depends on habitat variables at nest sites and if habitat quality influences reproduction. Methods Breeding density was explored in northwestern Switzerland from 1992 to 1996. Habitat variables were examined at 38 breeding sites and were compared with data collected from random sites. Habitat quality was estimated using the discriminant function scores of the nesting sites. Results Breeding density was found to vary between years; more pairs bred and raised more young in 1993, a year of high vole abundance. Long-eared Owls tended to avoid the vicinity of buildings; they occupied sites with denser forest edges, greater canopy cover, and with more conifers than random sites. I found no statistical evidence that they used less optimal sites when the population was high. The number of fledglings increased with habitat quality, but did not vary with any of the habitat variables taken separately. Conclusion Long-eared Owl selects nesting habitat as part of an anti-predator strategy, but the measures of territory quality did not seem to be a limiting factor for the population. 相似文献
5.
Evidence Of Botanical Diversity and Species Continuity from Chancay Sites in The Huaura Valley, Peru. This study reports on new botanical evidence from the north-central coast of Peru. The material dates to the Late Intermediate
Period (approximately CE 1100–1435) and is from archaeological excavation at the sites of Rontoy, Quipico, and Chambara located
in the Huaura Valley. All three sites belong to what has been defined as the Chancay culture. The diversity of species present
is consistent with the plants utilized in the region beginning in the Preceramic Period. Data also show differential distribution
of plant taxa by site that cannot be explained by ecological zone or site location. 相似文献
6.
Capsule Foraging sites with low vegetation height and density, but with high arthropod biomass, are selected. Aims To test the hypothesis that on intensively grazed moorland, breeding Meadow Pipits forage for nestling food where arthropod prey are most readily available, and therefore that foraging site choice is a function of prey abundance and vegetation structure. Methods Observations of adults provisioning nestlings were made from hides positioned close to 19 nests within grazed, 3.3-hectare experimental plots at Glen Finglas, Scotland. Vegetation height and density and arthropod abundance from mapped foraging sites were compared with control sites. Prey items fed to nestlings were quantified and compared with their relative abundance. Results Meadow Pipits selected foraging sites with significantly lower vegetation height and density, but with significantly higher arthropod biomass. Our data suggest that within foraging sites, Meadow Pipits select particular prey types to provision nestlings, in particular, Lepidoptera larvae, adult Tipulidae and Arachnida. Conclusions In intensively grazed upland systems, it appears that Meadow Pipits select foraging sites that optimize total food abundance and accessibility. In order to understand how anticipated changes to livestock farming in Europe will affect grassland birds, we recommend that future studies should investigate the foraging and vigilance behaviour, diet composition and breeding success of a variety of bird species provisioning nestlings under a range of livestock management scenarios. 相似文献
7.
《Plains anthropologist》2013,58(50):237-250
AbstractData from two groups of burned rock midden sites are presented. Occupation of the sites seems to have been heaviest during Archaic times, with some Late Prehistoric and possible Paleo-Indian components also recognized. A burial is described from one site. Problems pertaining to burned rock midden sites are briefly discussed. 相似文献
8.
Mark J. Whittingham Ailsa J. McKenzie Richard M. Francksen David Feige Tom Cadwallender Matthew Grainger 《Bird Study》2019,66(4):431-440
ABSTRACTCapsule: Wintering Ruddy Turnstones Arenaria interpres occur in higher densities and their populations decline less on, or close to, offshore refuges than on mainland sites subject to greater levels of human disturbance.Aim: To compare wintering densities of Ruddy Turnstones and changes in counts across time from sites with differing levels of human disturbance.Methods: Long-term counts of Ruddy Turnstones (1998/1999 to 2015/2016) were used from 19 sites (two offshore refuges and 17 mainland sites subject to higher levels of human disturbance) in northeast England. No direct measure of human disturbance was available for our mainland sites; instead we used questionnaires (n?=?690) to understand how far people travelled to visit the coast and then used this distance with human population densities in a buffer around each site as a proxy for human disturbance levels.Results: After controlling for the extent of their preferred habitat at each site (rocky shore) we found: (i) the closer each of the 19 sites was to the nearest offshore refuge the higher the density of Ruddy Turnstones and (ii) bird counts were stable at the two refuge sites, whereas, on average, counts declined at the 17 mainland sites. However, no relationship was found between Ruddy Turnstone counts from 17 mainland sites and human population densities within differing distances from each site (up to 10?km).Conclusions: Our work suggests that Ruddy Turnstones made greater use of relatively undisturbed areas (offshore refuges) than those subject to greater disturbance by humans (mainland sites). Although the use of refuges and mainland in our study area was not well known, observations from 11 radio-tagged Ruddy Turnstones suggest that individual birds did use both locations. In a broader context, our work concurs with other studies that highlight the need for refuges with limited or no human access. 相似文献
9.
ABSTRACT Capsule: Duration and peak frequency of Wren Troglodytes troglodytes songs differ between Welsh islands (Skokholm, Flat Holm, and Sully Island) and a mainland site, suggesting random or cultural divergence. Aims: The study tests for differences in bioacoustic traits in Wren song between four breeding sites. Methods: Songs from breeding male Wrens were recorded from three Welsh islands and a representative location on the local mainland. Each sonogram was measured for six variables from the whole song and two distinct phrases from the beginning and middle. The variables were measured manually using an open source acoustic tool and compared between sites using generalized linear mixed-effects models. Results: There was significant variation in song variables between island sites and the mainland. Skokholm Wren songs were significantly longer in duration than all other sites by up to 66%. Peak frequency was significantly different across all sites with Sully Island having the highest peak frequency and Skokholm the lowest. Conclusion: The differences in song duration and frequency do not directly suggest a trend associated with selective pressures such as habitat or noise, but instead may be explained by non-selective drivers such as cultural drift or local dialect formation. 相似文献
10.
Lu Gong 《法国昆虫学会纪事》2018,54(2):111-118
Two new species of the genus Apsiphortica are described from China: A. orthophallos n. sp. and A. sinuatipenis n. sp. Species delimitations are improved by integrating morphological and DNA barcoding information. The intra- and interspecific pairwise p-distances (proportional distance) are summarized for five Apsiphortica species from China. Furthermore, nucleotide sites with fixed status in the alignment of the COI sequences (639 nucleotide sites in length) are used as “pure” molecular diagnostic characters to delineate the five species. A key to all the Chinese species of the genus Apsiphortica is provided. 相似文献
11.
《Biochimica et Biophysica Acta (BBA)/General Subjects》2023,1867(10):130424
BackgroundS1-like nucleases are widespread enzymes commonly used in biotechnology and molecular biology. Although it is commonly believed that they are mainly Zn2+-dependent acidic enzymes, we have found that numerous members of this family deviate from this rule. Therefore, in this work, we decided to check how broad is the range of non‑zinc-dependent S1-like nucleases and what is the molecular basis of their activities.MethodsS1-like nucleases chosen for analysis were achieved through heterologous expression in appropriate eukaryotic hosts. To characterize nucleases' active-site properties, point mutations were introduced in selected positions. The enzymatic activities of wild-type and mutant nucleases were tested by in-gel nuclease activity assay.ResultsWe discovered that S1-like nucleases encoded by non-vascular plants and single-celled protozoa, like their higher plant homologues, exhibit a large variety of catalytic properties. We have shown that these individual properties are determined by specific non-conserved active site residues.ConclusionsOur findings demonstrate that mutations that occur during evolution can significantly alter the catalytic properties of S1-like nucleases. As a result, different ions can compete for particular S1-type nucleases' active sites. This phenomenon undermines the existing classification of S1-like nucleases.General significanceOur findings have numerous implications for applications and understanding the S1-like nucleases' biological functions. For example, new biotechnological applications should take into account their unexpected catalytic properties. Moreover, these results demonstrate that the trinuclear zinc-based model commonly used to characterize the catalytic activities of S1-like nucleases is insufficient to explain the actions of non‑zinc-dependent members of this family. 相似文献
12.
《Journal of bryology》2013,35(4):264-267
AbstractGrimmia anomala is reported from seven sites in Scotland and Ireland. Confusion in the past with Grimmia hartmanii has meant that this species has been overlooked. Its occurrence in Scandinavia and the Faroes means that its sites in Scotland are not unexpected but the Irish localities for this boreal-montane species are noteworthy. 相似文献
13.
《Plains anthropologist》2013,58(31):41-76
AbstractThe materials collected from four sites on the Little Bend of the Missouri River are described and analyzed. In the conclusion, these manifestations, referred to as the No Heart Creek complex, are compared to seven other sites along the river in north.-central South Dakota. The sites are related to the Le Compte Focus and are characterized by a distinetive settlement pattern. 相似文献
14.
15.
《Plains anthropologist》2013,58(41):228-241
AbstractCeramics recovered from the Gettysburg Site during the summers of 1964, 1965, and 1966 are described and analyzed. A comparison is made with ceramic collections from 19 other sites in the Middle Missouri Valley. Concluding comments demonstrate the relationship of the Gettysburg Site to sites of the Extended Coalescent Horizon. 相似文献
16.
Rates and outcomes of testing for lynch syndrome in a national colorectal cancer screening programme
BackgroundLynch Syndrome (LS), the most common cause of hereditary colorectal cancer (CRC), is characterised by pathogenic variants in mismatch repair (MMR) genes. Universal testing of all CRCs for LS can increase detection. Rates and outcomes of testing in Ireland’s national CRC screening programme have not been examined previously.MethodsCRCs diagnosed at two screening sites between 2015 and 2020 were identified. Patient records were used to determine if CRCs had been tested for MMR deficiency and if detected, what downstream testing to rule out LS or genetic testing to confirm LS was undertaken.ResultsOver five years, 206 CRCs were diagnosed. Testing for LS was carried out for 100% of CRCs at site A and 69% of CRCs at site B. Of CRCs tested for LS, 14 (8%) were MMR deficient. After downstream testing for BRAF mutation or hypermethylation of MLH1, three CRCs were identified as potentially LS-related. Of these two individuals declined genetic testing and one was lost to follow-up.ConclusionsBy 2020 both sites had implemented universal testing of all CRCs for LS. A small number of individuals were identified as being eligible for genetic testing for LS, however those offered declined testing and one individual was lost to follow up. This highlights the importance of universal testing and the need for referral pathways to ensure all appropriate individuals are referred onwards to genetic services. 相似文献
17.
《Plains anthropologist》2013,58(39):63-70
AbstractTwo sites bearing Apachean pottery are reported from north central New Mexico. Using the archeological, ethnographic, and historical records, it is suggested that the sites were occupied by Jicarilla Apaches during the second half of the nineteenth century. 相似文献
18.
《Plains anthropologist》2013,58(46):253-271
AbstractMill Creek ceramics from northwest Iowa are used to derive a sequence of occupations for sites along the Little Sioux River and its tributaries. Previous typologies and attempts at seriation of sites are examined and tested. The methods employed in this study are evaluated, and the resulting seriation is cross-checked with stratigraphic evidence and a series of radiocarbon dates. 相似文献
19.
《Plains anthropologist》2013,58(74):311-312
AbstractThirteen radiocarbon dates from mound and habitation sites, and from late Quaternary spring deposits in the western Ozarks of Missouri are published here, several of them for the first time. 相似文献
20.
《Plains anthropologist》2013,58(62):344-349
AbstractProjectiles from nine Middle Missouri tradition sites in two contiguous archaeological regions are analyzed. These sites date from the 12th to 17th centuries. Discriminant Analysis was used to cluster sites on the basis of similarities in projectile size and shape. The site groupings provided by this analysis crosscut geographic boundaries, suggesting that the variation is not due to local manufacturing practices; rather, the noted differences probably reflect pattern changing through time. 相似文献