Interaction of foliage and larval age influences preference and performance of a geometrid caterpillar

2009 ◽  
Vol 141 (2) ◽  
pp. 136-144 ◽  
Author(s):  
Lauren Pinault ◽  
Graham Thurston ◽  
Dan Quiring
Keyword(s):  
Foraging Behaviour ◽  
Survival Rates ◽  
Field Studies ◽  
Tsuga Canadensis ◽  
Fourth Instar ◽  
Eastern Hemlock ◽  
Age Classes ◽  
Balanced Diet ◽  
And Performance ◽  
Insect Fitness

AbstractIn two recent studies it was reported that feeding on foliage of multiple age classes can improve insect fitness, but it was not determined whether the increase in fitness was due to larvae obtaining a more balanced diet (the balanced-diet hypothesis) or to a difference in the nutritional requirements between young and old larvae (the ontogenetic hypothesis). To test these two hypotheses, we examined the foraging behaviour and performance of young (second or third to fourth instar) and old (third or fourth to fifth instar) larvae of the pale-winged gray moth, Iridopsis ephyraria (Walker) (Lepidoptera: Geometridae), on different-aged foliage of eastern hemlock, Tsuga canadensis (L.) Carrière (Pinaceae), during an outbreak in southwestern Nova Scotia. Defoliation attributed to I. ephyraria was highest on current-year foliage and gradually declined with foliage age. Young larvae were only observed feeding on current-year shoots but old larvae fed on foliage of all ages. When forced to feed on foliage of specific ages in manipulative field studies, survival rates of young and old larvae were highest on current-year and old (≥1 year old) foliage, respectively. However, both young and old larvae had higher survival rates when provided with access to foliage of all age classes than when they were forced to feed on only young or old foliage. Thus, this study supports both the balanced-diet and ontogenetic hypotheses.

scholarly journals Fire and Its Interactions With Other Drivers Shape a Distinctive, Semi-Arid ‘Mallee’ Ecosystem

2021 ◽  
Vol 9 ◽  
Author(s):  
Michael F. Clarke ◽  
Luke T. Kelly ◽  
Sarah C. Avitabile ◽  
Joe Benshemesh ◽  
Kate E. Callister ◽  
...  
Keyword(s):  
Regional Scale ◽  
Fire Regimes ◽  
Field Studies ◽  
Arid Ecosystems ◽  
Coarse Grained ◽  
Pest Species ◽  
Age Classes ◽  
Eastern Australia ◽  
Animal Communities ◽  
Semi Arid

Fire shapes ecosystems globally, including semi-arid ecosystems. In Australia, semi-arid ‘mallee’ ecosystems occur primarily across the southern part of the continent, forming an interface between the arid interior and temperate south. Mallee vegetation is characterized by short, multi-stemmed eucalypts that grow from a basal lignotuber. Fire shapes the structure and functioning of mallee ecosystems. Using the Murray Mallee region in south-eastern Australia as a case study, we examine the characteristics and role of fire, the consequences for biota, and the interaction of fire with other drivers. Wildfires in mallee ecosystems typically are large (1000s ha), burn with high severity, commonly cause top-kill of eucalypts, and create coarse-grained mosaics at a regional scale. Wildfires can occur in late spring and summer in both dry and wet years. Recovery of plant and animal communities is predictable and slow, with regeneration of eucalypts and many habitat components extending over decades. Time since the last fire strongly influences the distribution and abundance of many species and the structure of plant and animal communities. Animal species display a discrete set of generalized responses to time since fire. Systematic field studies and modeling are beginning to reveal how spatial variation in fire regimes (‘pyrodiversity’) at different scales shapes biodiversity. Pyrodiversity includes variation in the extent of post-fire habitats, the diversity of post-fire age-classes and their configuration. At regional scales, a desirable mix of fire histories for biodiversity conservation includes a combination of early, mid and late post-fire age-classes, weighted toward later seral stages that provide critical habitat for threatened species. Biodiversity is also influenced by interactions between fire and other drivers, including land clearing, rainfall, herbivory and predation. Extensive clearing for agriculture has altered the nature and impact of fire, and facilitated invasion by pest species that modify fuels, fire regimes and post-fire recovery. Given the natural and anthropogenic drivers of fire and the consequences of their interactions, we highlight opportunities for conserving mallee ecosystems. These include learning from and fostering Indigenous knowledge of fire, implementing actions that consider synergies between fire and other processes, and strategic monitoring of fire, biodiversity and other drivers to guide place-based, adaptive management under climate change.

scholarly journals Foraging behaviour and performance of steers from two local breeds (Asturian Valley and Asturian Mountain) grazing in Cantabrian (N Spain) summer pastures

2019 ◽  
Vol 17 (1) ◽  
pp. e0601
Author(s):  
Alicia Román-Trufero ◽  
Antonio Martínez ◽  
Luis M. M. Ferreira ◽  
Valentín García-Prieto ◽  
Rocío Rosa-García ◽  
...  
Keyword(s):  
Body Weight ◽  
Body Size ◽  
Diet Composition ◽  
Foraging Behaviour ◽  
Meat Production ◽  
Market Demand ◽  
Nutrient Requirements ◽  
Northern Spain ◽  
Sward Height ◽  
And Performance

Steer meat production in northern Spain is deficient to attend market demand. This research aimed to compare the foraging behaviour and production of yearling steers from two local breeds differing in body weight (BW), Asturian Valley (AV, 372 kg) and Asturian Mountain (AM, 307 kg), grazing in summer pastures consisting of 70% grassland and 30% heathland. Bodyweight gains from a total of 42 steers were recorded during four grazing seasons (from June to October). In two years, in July and September, plant community selection and diet composition were estimated by direct observation and using faecal markers, respectively. Grazing time increased from July to September (488 vs. 557 min/day; p<0.001) as sward height in the grassland decreased. Although AV steers grazed proportionally for longer on herbaceous pastures than AM steers (81.3 vs. 73.3%; p<0.05), no differences between breeds were found in diet composition. AM steers showed greater mean daily BW gains than AV steers (252 vs. 133 g/day; p<0.01). From June to August, steers from both breeds gained BW (487 vs. 360 g/day for AM and AV, respectively; p<0.01), but thereafter BW gains decreased (120 vs. –12 g/day for AM and AV, respectively; p<0.05), because of reduced availability of grassland herbage. Yearling steers from AM breed seem to be better suited to mountain conditions than those from AV breed, probably because of their smaller body size and lower total nutrient requirements for maintenance.

scholarly journals Breathing Artifacts of Urban BioClimatic Layers for Post-Anthropocene Urban Environment

2021 ◽  
Vol 13 (20) ◽  
pp. 11307
Author(s):  
Marie Davidová
Keyword(s):  
Urban Design ◽  
Data Model ◽  
Architectural Design ◽  
Cultural Landscape ◽  
Visual Complexity ◽  
Field Studies ◽  
Qualitative Synthesis ◽  
Hard Data ◽  
And Performance ◽  
Climate Comfort

This article seeks the qualitative synthesis of schools of thought from extreme climate regions that could support urban biodiversity and climate change adaptation through architectural design. It proposes that climate comfort and biodiversity are closely related. This article suggests a possible systemic urban metabolism within a built environment that can support a transition to post-Anthropocene, where humans and other species live together in synergy. This article exemplifies and seeks systemic relations and reflections of gathered field studies documentation of case studies of breathing walls, envelopes, and screens generating bioclimatic layers in the cultural landscape, selected for their penetrability and performance. The samples from diverse study journeys that were codesigned through vernacular cultures and the author’s research by design speculations on the responsive screen ‘Ray’ are investigated and speculated upon through gigamapping (visual complexity mapping). This gigamapping is not to present any hard data model but to relate, inform and speculate on the investigated field that is grounded in research by design on cross-species coliving. This is approached through possible architectures and architectural and urban design parasites, transitioning towards synergetic landscapes of our envisioned colived and cocreated futures.

scholarly journals LOGS AS REFUGES FROM FUNGAL PATHOGENS FOR SEEDS OF EASTERN HEMLOCK (TSUGA CANADENSIS)

Ecology ◽  
2004 ◽  
Vol 85 (1) ◽  
pp. 284-289 ◽  
Author(s):  
D. L. O'Hanlon-Manners ◽  
P. M. Kotanen
Keyword(s):  
Fungal Pathogens ◽  
Tsuga Canadensis ◽  
Eastern Hemlock

USE OF THE RELATIVE TURGIDITY TECHNIQUE FOR MEASUREMENT OF WATER STRESSES IN GYMNOSPERM LEAVES

1965 ◽  
Vol 43 (2) ◽  
pp. 305-316 ◽  
Author(s):  
J. J. Clausen ◽  
T. T. Kozlowski
Keyword(s):  
Abies Balsamea ◽  
Pinus Resinosa ◽  
Tsuga Canadensis ◽  
Red Pine ◽  
Eastern Hemlock ◽  
Balsam Fir ◽  
White Pine ◽  
Sampling Variation

Adaptations of Weatherley's relative turgidity technique (Weatherley 1950), fitting it for use with red pine (Pinus resinosa Ait.), white pine (P. strobus L.), balsam fir (Abies balsamea (L.) Mill.), and eastern hemlock (Tsuga canadensis (L.) Carr.) are described. Results of preliminary investigations of sampling variation between trees, whorls, and needle ages in red pine are presented.

Changes in Form and Style in Randai Performance at The Minangkabau Diaspora in Malaysia

2022 ◽  
Vol 21 (2) ◽  
pp. 340-355
Author(s):  
Indrayuda Indrayuda ◽  
Mohd Effindi Samsuddin
Keyword(s):  
Local Community ◽  
Field Studies ◽  
Peninsular Malaysia ◽  
Snowball Sampling ◽  
Long Distance ◽  
Taxonomic Analysis ◽  
Study Results ◽  
Observation Instruments ◽  
Cultural Themes ◽  
And Performance

This article reveals the changes in form and style of the Randai performance performed by the Minangkabau’s diaspora in Malaysia. The novelty of this research is the study of changes in forms and styles in Randai carried out by the Malaysian Minangkabau diaspora. The disconnection of socio-cultural communication and the long distance between Minangkabau and Peninsular Malaysia impacts the shift in forms and styles of Randai in the Minangkabau diaspora. This research was conducted qualitatively by designing research works such as pre-field studies, by collecting preliminary data based on a diffusion approach. In the field stage, the informants were selected by snowball sampling. The interview and observation instruments were designed based on the performance structure and performance procedures. Researchers conducted data analysis using the techniques recommended by Spradley, namely: (1) domain analysis, (2) taxonomic analysis, (3) componential analysis, and (4) discovering cultural themes. The study results revealed that the forms and styles were caused by mixing cultures between the diaspora and the Malaysian Malays. These changes were done so that the local community could accept Randai. In addition, Randai can be easily learned and cultivated by the Malay Malays and easily expressed by the Malaysian community and the Minangkabau diaspora as the perpetrators of Randai. These changes occur through a process of adaptation and acculturation. The implication of this research is the emergence of a new Randai model, namely Randai, which refers to local culture, both from the aspect of the story, Silat style, and music, as an identity and tradition for the Malaysian Minangkabau diaspora for the future.

scholarly journals 66. Field Research in EMS: Who is Doing the Work?

1996 ◽  
Vol 11 (S2) ◽  
pp. S36-S36
Author(s):  
David R. Johnson ◽  
Mark B. Napier
Keyword(s):  
Educational Institution ◽  
Field Research ◽  
Field Studies ◽  
System Structure ◽  
Public And Private ◽  
Exact Test ◽  
Critical Data ◽  
And Performance ◽  
Data Elements ◽  
Meta Analyses

Purpose: To determine what types of EMS systems (public vs. private) are contributing to the peer reviewed field research in EMS and what type of research is being done by these agencies.Methods: A Medline literature search was conducted of all peer reviewed journals using the search terms: EMS, emergency medical services, EMT, paramedic, and ambulance. Studies published between 1976 and 1995 meeting these criteria were reviewed and classified as field or non-field studies. Studies were classified as field studies if they evaluated clinical outcomes or overall EMS system structure and performance. The type of EMS system in which the study was conducted was classified as: public (PB), private (PR), or a mixture of public and private agencies (PP). If the type of system was not evident in the paper, the primary author or EMS agency was contacted by phone. The primary affiliation of the first author was classified as being with: an educational institution, hospital, government agency, or EMS agency. Each study was also classified as being primarily clinical or evaluating EMS system structure. Review articles, editorials, and meta-analyses were excluded as were studies in which critical data elements could not be verified. Fischer's exact test was used for statistical analysis.Results: A total of 365 studies were evaluated with 66 non-field studies being excluded from analysis. 75 studies did not meet inclusionary criteria. This left 224 studies for analysis. PB systems accounted for 167 (74.5%) of field studies, with PP 44 (19.6%) and PR 13 (5.8%). Clinical studies were more commonly done by PB systems (72.5%) when compared to PR systems (38.5%), p = 0.02. System structure studies accounted for the majority of studies done by PR systems (61.5%). An affiliation with an educational institution such as a university occurred in 61.2% of the studies. The number of field studies done by PB systems has increased steadily over the last 10 years while field studies published by PR and PP systems has remained at a low level, with none published from 1992–1994.

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