The importance of grasstrees (Xanthorrhoea preissii) as habitat for mardo (Antechinus flavipes leucogaster) during post-fire recovery

2007 ◽  
Vol 34 (8) ◽  
pp. 640 ◽  
Author(s):  
Marnie L. Swinburn ◽  
Patricia A. Fleming ◽  
Michael D. Craig ◽  
Andrew H. Grigg ◽  
Mark J. Garkaklis ◽  
...  

Grasstrees (Xanthorrhoea) are an important structural component of many Australian ecosystems and also an important resource for many fauna species. Grasstrees have distinctive morphologies, with a crown of long thin leaves and skirts, the latter of which are accumulated dead leaves; both are incinerated by fire. This study determined the morphological features of Xanthorrhoea preissii, which change in response to fire from 6 months to 21 years post-burn. In addition, using radio-telemetry and spool-tracking, we determined that grasstrees are utilised as foraging and nesting resources for mardos (Antechinus flavipes leucogaster (Gray, 1841), Marsupialia: Dasyuridae). Recently burnt grasstrees (6 months post-burn) appeared not to be used by mardos at all. We found few mardos in these recently burnt sites, and the one individual we managed to track for 126 m utilised only a single grasstree: a 2-m-tall multiple-crowned grasstree that had escaped the fire was used as a nest site. For sites 5 years post-burn, mardos selectively utilised grasstrees with larger crown areas and those with a greater number of crowns compared with a random sample of available trees. At the 14-year post-burn sites, mardos still demonstrated some selection for grasstrees, although no specific single feature could be determined as most significant. We recorded humidity and temperature buffering effects in association with post-burn accumulation of grasstree skirt material and found that even dead grasstree ‘logs’ were an important resource for nests. We conclude that mardos utilise both live and dead grasstrees for foraging and nest sites, possibly owing to the availability of dense cover, a buffered microclimate, and potentially also food resources. Fire-management policies that promote habitat heterogeneity and retain several intact-skirted grasstrees within the landscape are likely to benefit mardos.

1988 ◽  
Vol 15 (5) ◽  
pp. 541 ◽  
Author(s):  
JR Ottaway ◽  
R Carrick ◽  
MD Murray

Aspects of the reproductive ecology of silver gulls, Larus novaehollandiae Stephens, were studied in South Australia during 1968-78. Some 15 950 pulli and 597 breeding adults were banded on 15 colonies, using numbered and coloured leg bands designed for identification of free-living individuals without the necessity of recapture. Nine colonies were on marine islands, four were on lacustrine islands, one was on a port breakwater, and one was on causeways in a saltworks complex. Fidelity to colony, mate and nest-site, and timing of breeding are considered in detail. The spatial relationship of adult and immature gulls, on the colony studied in greatest detail, and reproductive longevity of the gulls are also discussed. The gulls nested from June to December inclusive, although the commencement and length of breeding seasons varied between colonies and between years. There was a marked absence of 1-year-old gulls on breeding colonies. Of 3530 pulli banded on the major study colony, Penguin Island (37�30''S., 140�01''E.) at Beachport, in 1968, 950 were known to be alive in the 1970 breeding season. Almost 40% of these 2-year-olds were seen on breeding colonies, and mostly on the natal colony; however, only 0.3% were known to raise pulli, and a further 0.7% to produce eggs. Significant breeding activity therefore did not commence until the end of the third year, or later. The older, previously established breeders on Penguin Island were significantly more successful, and had significantly earlier laying dates, than younger birds. Potential reproductive longevity appears to be at least 11 breeding seasons. In this study, silver gulls showed considerably less fidelity to nest-sites and colonies than has been suggested previously. Significant shifts of nest-site, or change of colony, with or without the previous mate, were not uncommon. Of gulls banded on nests as established breeding aduls, 7-44% of gulls found breeding in subsequent years were at colonies other than the one where banded. In 1970, over 80% of 2-year-old gulls recorded present on any colony were only recorded on the natal one. Of the pulli banded on Penguin Island in 1968 and 1969 and later found actually nesting or breeding, 18% were recorded on other colonies. A small percentage of gulls were seen to have high fidelity to nest-site and to mate over 3 or 4 seasons, but it is suggested that, for some colonies, over 50% of silver gulls which eventually breed may do so at colonies other than natal. Significant spatial separation was found on Penguin Island between areas generally occupied by established breeders, which were known to be at least 4-year-olds, and by the 2-year-olds. The older birds may select and hold the territories most suitable for nesting, where vegetation or topography minimise intraspecific aggression which often leads to high mortality rates of eggs and pulli, and assist protection of eggs and pulli from extreme weather. Non-breeding gulls associating with the colonies occasionally move into the nesting areas, but are aggressively forced away and tend to congregate on the periphery of the colony or on exposed areas not suitable for successful breeding.


2014 ◽  
Vol 25 (2) ◽  
pp. 192-206 ◽  
Author(s):  
RYAN D. CLARK ◽  
RENAUD MATHIEU ◽  
PHILIP J. SEDDON

SummaryThe concealed and widely dispersed nests of the rare and endangered Yellow-eyed Penguin Megadyptes antipodes, or “hoiho”, have been considered to reflect an essential requirement for the visual isolation of nest sites from conspecifics. However, this may be a consequence of selection for habitat features that provide protection from insolation, thereby minimising the risk of heat stress. To help improve the understanding of hoiho nesting requirements and the effectiveness of habitat restoration, we aimed to determine whether visual isolation from conspecifics or protection from insolation is the primary driver of hoiho nest site selection. We compared the mean maximum distance of visibility and the mean percentage insolation cover of active nests with randomly sampled unused sites in flax Phormium tenax and Hebe elliptica coastal scrub at Boulder Beach, and in coastal forest at Hinahina Cove, New Zealand, 2006–2007. Results of univariate tests and the evaluation of logistic regression models suggested that the amount of insolation cover was more important than visibility for hoiho nest site selection, particularly in flax and scrub. In addition, Spearman's correlations indicated that decreasing insolation cover significantly increased the visibility of nests in the forest habitat, and had a similar effect on inter-nest distance in flax. We infer that hoiho nest site selection and distribution are influenced primarily by the location and density of micro-habitat features (particularly within 1 m of the ground) that provide optimal protection from insolation, possibly along with other important features such as a firm backing structure. Strong selection for these features results in the typical but non-essential visual isolation of nest sites from conspecifics. Restoration of nesting habitats with a relatively high density and diversity of vegetation and solid structures within 1 m of the ground may eventually provide an optimal availability and quality of suitable nest sites.


Virittäjä ◽  
1970 ◽  
Vol 125 (1) ◽  
Author(s):  
Ildikó Vecsernyés

Tässä artikkelissa tarkastellaan, kuinka Suomen ja Unkarin pääministereitä puhutellaan Facebookissa. Tutkimuksen kohteena on se, mitä puhuttelukeinoja kommentoijat käyttävät kahdessa eri tarkoituksessa: toisaalta sympatian tai samaa mieltä olemisen, toisaalta erimielisyyden tai kritiikin ilmaisemisessa. Kahden sukukielen, suomen ja unkarin, puhuttelukeinot ovat samankaltaisia, mutta niiden käytössä on huomattavia eroja esimerkiksi sinuttelun ja teitittelyn yleisyydessä. Aineistona on viiteen Suomen pääministeri Juha Sipilän ja yhdeksään Unkarin pääministeri Viktor Orbánin vuosina 2015–2017 kirjoittamaan Facebook-päivitykseen tulleita kommentteja. Tarkastelun kohteena on 189 suomenkielistä ja 191 unkarinkielistä puhuttelumuotoa sisältävää kommenttia. Kommentit on jaettu myötäileviin ja vastustaviin ja näitä kahta kommenttityyppiä tarkastellaan kvantitatiivisesti ja kvalitatiivisesti pyrkimyksenä selvittää, mitä eroja puhuttelumuodon valinnassa ilmenee. Tutkimuksen teoreettis-metodisena taustana on aiempi sosiopragmaattinen puhuttelututkimus. Tutkimus osoittaa, että suomessa sinuttelu on hyvin yleistä riippumatta kommentin laadusta, mutta unkarissa sinuttelu on tavallisesti erimielisyyden osoittamisen keino. Tyypillinen kannustavan kommentin kirjoittaja käyttää suomessa sinuttelua ja pääministerin etunimeä, unkarissa teitittelyä, ön-teitittelypronominia ja pääministerin titteliä. Unkarin kielessä puhuteltavan yhteiskunnallinen asema vaikuttaakin puhuttelumuodon valintaan vahvemmin kuin suomessa. Toissijaisena strategiana unkarissa esiintyy jonkin verran myös uudenlaista kunnioittavaa sinuttelua yhdistettynä pääministerin etunimen käyttöön. Suomenkielisen aineiston vastustavissa kommenteissa esiintyy vielä todennäköisemmin sinuttelua kuin myötäilevissä kommenteissa sekä sinä-pronominia ja pääministerin sukunimeä, unkarinkielisessä aineistossa puolestaan sinuttelua, te ’sinä’ -pronominia ja pääministerin etu- tai sukunimeä tai nimenmuunnoksia. Toissijaisena strategiana joissain unkarin vastustavissa kommenteissa hyödynnetään ylikohteliaisuutta ja intentionaalista inkoherenssia. Aineiston perusteella näyttää siltä, että Facebook-kommenteissa käytetään suomessa etupäässä sinuttelua samoin kuin muissakin internetkeskusteluissa; kommentoijien mielipiteen ilmaisemisessa nominaalisilla puhuttelumuodoilla on tärkeä rooli. Unkarissa taas internetin yleisestä sinuttelupainotteisuudesta huolimatta tärkeimpänä keinona on sinuttelun ja teitittelyn vastakkainasettelu.   How to address a Prime Minister? Forms of address in comments to posts from the Prime Ministers of Finland and Hungary This article examines how the Prime Ministers of Finland and Hungary are addressed on Facebook. The aim of the study is to investigate which forms of address are used by commentators expressing, on the one hand, sympathy or consent, and on the other, disagreement or criticism. The repertoires of address forms of these two related languages, Finnish and Hungarian, bear many similarities, but the frequency and status of these forms are different. The data consists of comments on five posts written by Prime Minister of Finland Juha Sipilä and on nine posts written by Prime Minister of Hungary Viktor Orbán between 2015–2017, comprising a total of 189 comments in Finnish and 191 comments in Hungarian, all containing forms of address. The comments have been divided into two types: comments showing sympathy and comments showing disagreement or criticism. These two comment types have been analysed quantitatively and qualitatively aiming to determine how the address practices employed differ from each other. The theoretical background of this study is based upon previously conducted socio­pragmatic address research. The article shows that the use of T forms  is very common in Finnish, regardless of the type of comment, but that in Hungarian, T forms are typically used as a linguistic tool to express disagreement. In Finnish, a typical commentator showing sympathy will use T forms and address the Prime Minister by his first name, whereas in Hungarian V forms, the V form pronoun ön, and the title ‘Prime Minister’ are favoured. The social status of the addressee has a stronger effect on the choice of address forms in Hungarian than it does in Finnish. However, some Hungarian comments include a new, respectful type of T form used with the first name of the Prime Minister. In comments expressing disagreement in the Finnish data, writers favour T forms, especially T form pronouns, and the use of the Prime Minister’s surname, whereas in the Hungarian data T forms, the T form pronoun te ‘you’ and the use of the Prime Minister’s first name, surname or nicknames are the most typical address practices. In conclusion, commentators in the Finnish data seem to use mostly T forms on Facebook, thus imitating address practices common in other online conversations. Instead of the T/V opposition, nominal forms of address play an important role in expressing the commentators’ attitude. In the Hungarian data, despite the prevalence of the T forms in online chats, the most important resource in expressing relation to the Prime Minister seems to be the contrast between the T and V forms, reflecting their significant status in Hungarian.


Agronomy ◽  
2020 ◽  
Vol 10 (5) ◽  
pp. 756
Author(s):  
Eva Edo-Tena ◽  
Russ W. Gesch ◽  
Aritz Royo-Esnal

The aim of the present work is to study possible differences in the germination behavior of apical and basal seeds (produced in the upper and lower fruits of the infruitescence), of two populations of field pennycress (Thlaspi arvense), both produced in a Mediterranean and a continental temperate climate. The results showed that among the three studied factors (population, seed type, production site), only the production site was relevant for the total germination, germinating those produced in Morris in a greater amount than those produced in Lleida. Germination models could be applied only to seeds produced at Morris (>10% germination), and despite the lack of differences in the total germination percentage, germination rates (speed—b parameter—and time to 50% germination—G50) differed between population and seed types—apical seeds from the Spanish population germinated faster (lower b parameter) than the rest, while apical seeds of both populations germinated faster than the corresponding basal seeds (lower G50). The results show, on the one hand, the importance of the seed production site if this species was considered as a commercial oilseed crop and, on the other hand, differences that will help seed selection for seed germination and establishment improvement of pennycress.


2019 ◽  
Vol 129 (2) ◽  
pp. 388-397
Author(s):  
Benjamin J Muller ◽  
Robin M Andrews ◽  
Lin Schwarzkopf ◽  
David A Pike

Abstract Microhabitat orientation and structure and the presence of conspecifics may strongly influence the choice of habitat. We studied how these variables influence retreat- and nest-site selection in gravid females of a globally successful invasive species, the Asian house gecko (Hemidactylus frenatus). When provided with various substrates (vertical and horizontal ceramic tiles, vertical and horizontal plywood tiles, horizontal bark over leaf litter, vertical bark over a log, and sand) gravid female geckos preferred to retreat to, and nest in, materials with crevices commonly found in urban habitats. When housed alone, gravid females most frequently retreated to vertical ceramic tile or wooden crevices, and 66.7% nested in vertical ceramic tiles. When housed with two other conspecifics, gravid females most frequently retreated to vertical ceramic tiles, but selected a wider range of nest sites. Overall, gravid geckos housed alone typically nested in the same substrates that they used as diurnal retreats; when housed in groups, however, females oviposited in locations different from those they selected as retreats. Thus, H. frenatus females use a wider range of substrates when conspecifics are present. Invasion success in this species might be driven, in part, by preferences for retreat and nest substrates that are common in human-dominated habitats.


1975 ◽  
Vol 32 (5) ◽  
pp. 633-642 ◽  
Author(s):  
A. F. Tautz ◽  
C. Groot

Detailed accounts of the spawning behavior of chum salmon (Oncorhynchus keta) and rainbow trout (Salmo gairdneri) in laboratory flumes are provided. The behavioral activities, quivering, probing, and crossing over increase in frequency as a function of time prior to spawning whereas digging remains constant or decreases slightly. Maps of digging locations and movie films suggest nest shape and current pattern are monitored by the female, allowing her to intensify her digging activity near the center of the nest. Probing appears to be a signal to the male indicating approach of oviposition and also provides information to the female regarding the shape and suitability of the nest site. The probing act is also used in the synchronization of the male and female spawning acts. Changes in velocity do not appear to markedly affect nest construction either in terms of number of digs to oviposition or in size of nest constructed. It is inferred that velocity and gravel size are important insofar as they influence the construction of a suitable nest depression. Nest sites would appear to be selected on the basis of acceleration of flow rather than velocity per se though high limits must obviously exist.


2006 ◽  
Vol 84 (11) ◽  
pp. 1533-1539 ◽  
Author(s):  
Rebecca Jo Safran

Despite hundreds of studies, we know very little about the causes and fitness-related consequences of nest-site selection. For example, it is not typically known whether the rarely reported fitness consequences of site selection are the result of nest, individual, or nest-site variables or combinations of these factors. Reuse of previously constructed nest sites is a prevalent behavior in many animals and offers the opportunity to experimentally tease apart whether seasonal reproductive success is a function of nest, individual, or nest-site characteristics. I used observational and experimental data to test three hypotheses related to these factors in association with barn swallow ( Hirundo rustica L., 1758) nest reuse. While both nest and individual characteristics explain variation in seasonal reproductive success, nest location per se is not an important factor defining the outcome of nest-site selection. Whereas traits related to habitat and individual characteristics are likely confounded in correlational studies, my experiments demonstrate a causal relationship between seasonal reproductive success and aspects of the nest and individual, the latter explaining more variation in the model than nest characteristics. Knowledge of the relative roles of individual, nest, and nest-site attributes are important for understanding the causes and consequences of habitat selection behavior.


1979 ◽  
Vol 6 (2) ◽  
pp. 205 ◽  
Author(s):  
DA Saunders

Data on nest hollows were collected from four study areas throughout the range of the short-billed form of the white-tailed black cockatoo, Calyptorhynchus baudinii latirostris, in south Western Australia. Hollows in trees are formed as a result of some destructive agent such as termites or fungi attacking the heartwood of the tree and breaking down the structure of the wood cells. The breaking off of part of the tree provides access to the hollow from the outside, and allows it to be used as a nest site. Throughout their breeding range, white-tailed black cockatoos will nest in any species of eucalypt which has a hollow of suitable size. The aspects of the entrances of hollows are not randomly distributed among compass groups, but the birds' selection of hollows was random. The aspect, depth to the floor and height of the entrance from the ground do not affect the success or failure of the nesting attempt. Female white-tailed black cockatoos searching for and preparing nest hollows chase female conspecifics from an area around their prospective nest tree. They continue this activity until they are incubating; this may result in suitable hollows not being accessible to other females. The rate of loss of hollows was 4.8 and 2.2% at two of the study areas. Hollows are being destroyed by all causes, particularly clearing for agriculture, faster than they are being created. Guidelines for the management of woodland must be drawn up so as to maintain a continuing supply of mature trees and protect hole-nesting species.


2019 ◽  
Vol 6 (9) ◽  
pp. 190886 ◽  
Author(s):  
Aurora García-Berro ◽  
Johanna Yliportimo ◽  
Kai Lindström ◽  
Charlotta Kvarnemo

The operational sex ratio (OSR, ready-to-mate males to females) is a key factor determining mating competition. A shortage of a resource essential for reproduction of one sex can affect OSR and lead to competition within the opposite sex for resource-holding mates. In the sand goby ( Pomatoschistus minutus ), a fish with paternal care, male readiness to mate depends on acquiring a nest-site, whereas food abundance primarily impacts female egg production. Comparing body condition and gonadal investment of fish from two populations with different availability in resources (Baltic Sea: few nest-sites, more food; North Sea: many nest-sites, less food), we predicted females carrying more mature eggs in the Baltic Sea than in the North Sea. As predicted, ovaries were larger in Baltic Sea females, and so was the liver (storage of energy reserves and vitellogenic compounds) for both sexes, but particularly for females. More females were judged (based on roundness scores) to be ready to spawn in the Baltic Sea. Together with a nest colonization experiment confirming a previously documented difference between the two areas in nest-site availability, these results indicate a more female-biased OSR in the Baltic Sea population, compared to the North Sea, and generates a prediction that female–female competition for mating opportunities is stronger in the Baltic population. To our knowledge, this is the first time that female reproductive investment is discussed in relation to OSR using field data.


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