Use of evergreen and deciduous plants by nocturnal-roosting birds:A case study in Beijing

With continually increasing urbanization,the land cover in urban areas continues to change,resulting in the loss of biodiversity.Birds are highly sensitive to changes in habitat.Most forest birds perch on plants that provide increased safety to reduce the risk of predation,and small birds may also consider insulation when using roosting plants in winter because of cold weather.Landscaping plants thus shape the nocturnal roosting environment of urban birds,and proper planting is essential for the survival of birds at night.The use of roosting plants by urban birds should therefore be studied to provide a reference for landscaping.In the current study,we observed 1865 nocturnal roosting birds in Beijing from 2021 to 2022,with 23 species of birds from 12 families and 45 species of plants from 22 families recorded.Juniperus chinensis exhibited the highest bird rarity-weighted richness,followed by Fraxinus pennsylvanica,Phyllostachys propinqua,Pinus tabuliformis,and Ulmus pumila.The diameter at breast height,tree height,and crown width of plants used by birds was largest in summer and smallest in winter,and the perch height of birds was the highest in spring and summer and the lowest in winter.Birds used the highest proportion of deciduous plants in summer and the highest proportion of evergreen plants in winter.A significant seasonal difference in the use of evergreen and deciduous plants by small birds was noted,with a preference for deciduous plants in summer and evergreen plants in winter,while this preference was not found in large birds.These findings indicate that evergreen plants provide a vital nocturnal roosting environment for small birds in winter.To provide a better nocturnal roosting habitat for urban birds,we recommend paying attention to the combination of evergreen and deciduous plants when carrying out landscape construction.

Comparison of roosting habitat characteristics of two sympatric pheasants during springtime at Dazhong Mountain,southwestern China

Hume's Pheasant(Syrmaticus humiae) and the Silver Pheasant(Lophura nycthemera) are two sympatric bird species at Dazhong Mountain of Yunnan Province,southwestern China.We investigated characteristics of roosting habitats of the two pheasants from February to April,2004 in this area.Multiple statistics,Matryoshka and a habitat classification-tree were used to analyze the selection of roosting habitats of these pheasants. The results of the habitat classification-tree indicated that several separations occurred in their macro and micro roosting habitats in the study area. The two pheasants had similar crucial requirements for and selection of ecological roosting factors,which allow them to live in the same macrohabitat.Competition between these two pheasants was avoided by separation of spatial elements,such as roosting trees and topographic characteristics.For safety strategy,Hume's Pheasant adopted primarily a way of'uneasily found habitat cover plus easy escape',while the Silver Pheasant employed a unique way of'uneasily found habitat cover'.For tactics of keeping warm,Hume's Pheasant selected mainly a method of'suitable vegetation supplemented with suitable topography',while the Silver Pheasant chose a unique man-ner of'suitable vegetation'.

Disturbance increases high tide travel distance of a roosting shorebird but only marginally affects daily energy expenditure

Background:Anthropogenic disturbance can negatively affect an animal's energy budget by evoking movement responses.Existing research focuses mainly on immediate displacement as a disturbance effect,since this can be easily observed in the field. However, effects on movement over longer timescales are poorly examined and it is largely unknown if and to what extent they reflect immediate responses.Longer-term responses could for example be larger than immediate responses if birds, after disturbance, return to the original location and thereby travel twice the immediate disturbed distance. Methods:We combined GPS tracking data with observational data to quantify the effects of anthropogenic (air force and walkers) and non-anthropogenic disturbances on distances travelled by roosting Eurasian Oystercatchers (Haematopus ostralegus) during the non-breeding season. We compared immediate displacement after a disturbance with distance travelled during the entire high tide period (longer-term response), while accounting for environmental factors.Additionally,we calculated energy expenditure due to disturbance based on observed disturbance frequencies.Results:Disturbance resulted in an immediate displacement response of ~200 m (median).Air force disturbances tended to yield larger immediate responses than walker and,especially,than non-anthropogenic disturbances.Longer-term responses and immediate responses were approximately similar,suggesting that,over longer timescales,spatial disturbance effects in the study area remain confined to immediate effects.However,disturbances were infrequent (0.17 disturbances per bird per hour) and most disturbances were of natural origin (62%).Consequently, anthropogenic disturbance of roosting oystercatchers in the study area on average costs 0.08% of the daily energy expenditure. Conclusions:Our results suggest that immediate spatial responses to disturbance can be a useful proxy for spatial responses over longer timescales.Over the non-exhaustive range of conditions investigated,energetic consequences of spatial disturbance responses for an oystercatcher in the study area are marginal due to low disturbance levels.

Convergences in the diversification of bats

Twenty-five characters or suites of characters from bats are considered in light of changes in bat classification. Thecharacters include some associated with flower-visiting (two), echolocation (12), roosting (six), reproduction (two) and three areof unknown adaptive function. In both the 1998 and 2006 classifications of bats into suborders (Megachiroptera and Microchiropteraversus Yinpterochiroptera and Yangochiroptera, respectively), some convergences between suborders are the same (e.g.,foliage roosting, tent building), but others associated with echolocation differ substantially. In the 1998 phylogeny convergencesassociated with echolocation (high duty cycle echolocation, nasal emission of echolocation calls) occurred among the Microchiroptera.In the 2006 phylogeny, they occur between Yinpterochiroptera and Yangochiroptera. While some traits apparently aroseindependently in two suborders (e.g., foliage-roosting, tent building, low intensity echolocation calls, noseleafs, nasal emission ofecholocation calls, high duty cycle echolocation behaviour), others appear to have been ancestral (roosting in narrow spaces,laryngeal echolocation, stylohyal-tympanic contact, oral emission of echolocation calls, and small litter size). A narrow profilethrough the chest is typical of bats reflecting the thoracic skeleton. This feature suggests that the ancestors of bats spent the day insmall crevices. Features associated with laryngeal echolocation appear to be ancestral, suggesting that echolocation evolved earlyin bats but was subsequently lost in one yinpterochiropteran lineage .

Microhabitat characteristics related to seasonal roost switching:implications from a threatened and introduced cockatoo species in an urban landscape

Background:Communal roosting is a common avian social behaviour,which potentially provides foraging benefits,predation avoidance or thermoregulation in birds.To identify the crucial environmental factors associated with roost site selection,most studies have focused on the comparison of physical characteristics between roosts and non-roosts.However,the differences among roosts have usually been neglected and the causes of roost switching have seldom been investigated.Methods:To explore the variations among roost sites and assess the most influential environmental factors related to seasonal roost switching,we conducted a 105-day observation on an introduced population of critically endan-gered Yellow-crested Cockatoo(Cacatua sulphurea)in an urban environment in Hong Kong from 2014 to 2016.We identified seven roost sites that were occupied in different seasons and then measured their microhabitat character-istics in terms of land use types,human disturbance and microclimate temperature.To quantify these differences,we used Pearson’s chi-squared test,partial least squares determinant analysis(PLS-DA)and one-way repeated measures ANOVA,respectively.Results:Our results distinguished roost sites occupied in three seasons,i.e.spring,summer and winter roosts,using several microhabitat characteristics.The land use types were significantly associated with roosts,where spring roosts were usually located in tree-dominated areas,which are the major feeding grounds.The discriminant analysis on human disturbance variables indicated that summer roosts were positively associated with night illumination.The microhabitat temperatures of winter roosts were significantly higher than those of most other roosts on cold nights.Conclusions:The results highlighted significant variations among roosts,and seasonal roost switching was likely driven by specific microhabitat characteristics of each roost site,such as microclimate.It also helps us understand the behavioural adaptation of birds to urban environments.

Biometrics and wing molt in White-winged Black Tern (Chlidonias leucopterus) in north-west Australia

We analyze morphometrics from a sample of 276 White-winged Black Tern(Chlidonias leucopterus) caught in north-west Australia on 4 March 2011. An estimated 40000 terns were present — the largest concentration of this species yet reported from Australia. When comparing juveniles with adults, only wing length and body mass differed significantly; however, juveniles were still easily recognized by plumage and wing molt as late as March. There was little evidence of any dramatic weight gain in adults before their northward migration. No morphological characteristic distinguishing sex was found. We confirmed that terns caught in this study did not appear to differ morphologically from those of the western palearctic populations. We describe wing molt based on data from 354 individuals captured and banded in Australia over 28 years. Wing molt proceeds in much the same way as found in other small terns.

Spatial Distribution of Regenerated Woody Plants in <i>Alnus hirsuta</i>(Turcz.) var. <i>sibirica</i>Stand in Japan

The role of N2 fixation in structuring plant communities and influencing ecosystem function will be potentially large. In previous study, we investigated nodule biomass and activity, and calculated the amount of N2 fixation in a naturally established 18-year-old alder (Alnus hirsute (Turcz.) var. sibirica) stand following disturbance by road construction in Takayama, central Japan. In this study, to estimate the facilitation effects by alder on the spatial distribution of the regenerated tree species, we examined the distribution pattern of the regenerated tree species in this naturally established 18-year-old alder stand. The distribution pattern of alder and the regenerated woody species was analyzed in terms of spatial point processes and the regenerated species tended to distribute near the alder site. In particular, bird-dispersed tree species (endozoochory species) with relatively high shade tolerance showed a significant attraction to alder. These results suggest that alder will be used as roost trees and play the role of mother trees for these regenerated species at the degraded site. It was also suggested that the endozoochory species, which occupy 13 of 26 regenerated species in this stand, might regenerate faster than other species at this alder stand.

Latidens salimalii （Endemic, Endanger Fruit Bat） A Reliable Propagator of Endemic Trees of Southern Western Ghats

Salim Ali＇s fruit bat （Latidens salimalii） is Endemic to Southern Western Ghats. India and is classified as Endangered by IUCN. Latidens is morphologically adapted to play a major role in the propagation of economically important trees： some of them are endemic to southern Western Ghats. This paper describes and documents, the bat＂s ecology, foraging behavior and food selection. The study is based on the dietary details of the discovered populations of L. salimalii in the Agasthiyar hill range and the High Wavy Mountains of southern Western Ghats, India. Seeds. partially eaten fruits and seedlings germinated on the floor of the feeding roosts confirm this bat forage for fruits among relatively tall trees of evergreen forests in an elevation above 900 meter. Mist netting below and above canopy near the fruiting and flowering trees of their foraging area confirmed their interaction with certain endemic tree species. Their species specific dietars＇ preferences immensely help to restore and bring back the natural forest community structures.

Habitat selection of the Tibetan Snow Cock Tetraogallus tibetanus in the spring in Lhasa

The habitat selection of Tibetan Snow Cocks in shrub vegetation was investigated in Lhasa,Tibet,China,between March and April,2005.Fourteen parameters were measured.These include altitude,slope,slope aspect,slope position,vegetation cover,plant type and other environmental parameters.Results show that Snow Cocks favor foraging in areas where vegetation cover was small and close to the residents’houses.Supplementary food supplied by humans has caused Snow Cocks to decrease their foraging range.Snow Cocks also favor roosting in areas with low vegetation,sparse grass,short grass,large rocks and close to houses.The Snow Cocks’activity in the study areas show a close relationship with human activities.

Crocodiles Rule the Roost in Far North Australia

选注者言:本文描述的是澳大利亚的一个鳄鱼保护区里的故事,内容生动可读,信息丰富动人。但是,就语言表达而言,本文出现的一个现象值得读者注意。首先,本文标题中的Rule the Roost是一个英语成语,含义是:当家;为首;为王。而初学者则容易将此成语当作Rule+the Roost(统治+栖息处)去理解。所幸的是,聪明的读者也能从“统治+栖息处”的意思推断出“当家;为首;为王”的理解,但是,并非所有的英语成语均能如此顺利“推断”,比如,本文的结尾处,出现了plunge pool。什么叫plunge pool是一个习惯搭配,意思是“瀑布下的水潭”,假如,读者不知道这个习惯搭配,而是根据plunge+pool的意思“游泳+池”(plunge确实有“游泳”的意思)去猜想,那就麻烦了!