The influence of insects on the distribution, microhabitat choice, and behaviour of the Burwash caribou herd

1986 ◽  
Vol 64 (3) ◽  
pp. 622-629 ◽  
Author(s):  
C. M. Downes ◽  
J. B. Theberge ◽  
S. M. Smith
Keyword(s):  
Avoidance Behavior ◽  
Yukon Territory ◽  
Microhabitat Use ◽  
Seasonal Activity ◽  
Mosquito Density ◽  
Activity Budgets ◽  
Microhabitat Choice ◽  
Resting Time ◽  
And Behavior

This study examined the influence of insects (mosquitoes and oestrids) on the distribution, microhabitat choice, and behavior of a population of mountain caribou. The study was conducted in the Burwash area of southwestern Yukon Territory during the summers of 1982 and 1983. Mosquito density, the presence or absence of oestrids, and the distribution, microhabitat use, and insect-avoidance behavior of the caribou were observed. Seasonal activity budgets for caribou were calculated. Mosquitoes became active in mid-June. Activity decreased with altitude, and at the highest altitudes (2000 m) the number of mosquitoes was negligible. Snow patches and exposed windy ridges had fewer mosquitoes than did open tundra. The oestrid season began in late June and lasted until early August. Oestrids were widespread throughout the study area and were present in all microhabitats. Caribou reduced harassment by mosquitoes by their altitudinal movements and use of microhabitat. Oestrids influenced activity budgets of caribou, acting to decrease feeding and resting time and to increase the time spent standing and moving.

Defense Mechanisms in Notaspid Snails: Acid Humor and Evasiveness

1991 ◽  
Vol 156 (1) ◽  
pp. 335-347 ◽  
Author(s):  
RHANOR GILLETTE ◽  
MAYUKO SAEKI ◽  
RONG-CHI HUANG
Keyword(s):  
Acid Secretion ◽  
Avoidance Behavior ◽  
Defense Mechanisms ◽  
Body Wall ◽  
Potential Role ◽  
Sea Water ◽  
Neural Pathways ◽  
Pleurobranchaea Californica ◽  
Local Contraction ◽  
And Behavior

Notaspid snails are known for their defensive skin secretion of sulfuric acid (pH 1–2) in response to noxious stimuli. We observed acid secretion and behavior in five notaspid species, and studied them in detail in Pleurobranchaea californica. All species secreted acid in response to skin abrasion or compression. Moreover, all species showed stereotypic avoidance behavior to acidified sea water less acidic (pH 2–3) then their own secretions. In Pleurobranchaea, secretion could also be stimulated by dilute solutions of taurine, 10−5-10−2moll−1. Secretion began at the stimulated region and spread slowly for about a minute following stimulation. Local contraction and transient edema of the skin were associated with acid secretion. In de-ganglionated preparations secretion could be caused by orthodromic stimulation of body wall nerves, by mechanical stimulation or by taurine. These data suggest that acid secretion is a positive feedback process modulated by inhibitory paths and coordinated by both central and peripheral nervous systems. A picture emerges of a defensive secretory response that provides an additional noxious stimulus initiating or potentiating avoidance behavior. The data also suggest a potential role for taurine release from injured tissue and the existence of specific nociceptive neural pathways regulating complex behavior. In addition to deterring extraspecific predation, acid secretion could regulate interactions between animals of the same species.

Day-roosting activity budgets of the eastern pipistrelle bat, Pipistrellus subflavus (Chiroptera: Vespertilionidae)

1996 ◽  
Vol 74 (3) ◽  
pp. 431-441 ◽  
Author(s):  
Jane M. Winchell ◽  
Thomas H. Kunz
Keyword(s):  
Post Partum ◽  
Video Camera ◽  
Time Of Day ◽  
Myotis Lucifugus ◽  
Seasonal Activity ◽  
Activity Budgets ◽  
Little Brown Bat ◽  
Eastern Pipistrelle ◽  
Pipistrellus Subflavus ◽  
Temperature Time

Daily and seasonal activity budgets of adult female eastern pipistrelle bats, Pipistrellus subflavus, were quantified at a maternity colony in eastern Massachusetts. Ambient and roost temperatures were recorded. Activities of roosting bats were monitored using an infrared-sensitive video camera. Scan sampling was used to analyze video records taken at weekly intervals from mid-May to late July 1989. Analysis of day-roosting indicates that adult females spend an average of 77% of their time at rest, 16% alert, 7% grooming, and < 1% crawling. Bats were most active immediately following their morning return to the day-roost and just prior to their departure at dusk. Periodic bouts of activity throughout the day were usually associated with urination and (or) defecation, mother–pup interactions, and movements in response to changes in roost temperature. Females were significantly more active in mortise roosts than when roosting on the open ridgepole, probably because fluctuations in temperature in mortises were smaller. As the season progressed, the overall time that bats spent resting decreased from 86 to 70%, whereas time spent alert increased from 9 to 24%; weekly fluctuations in the incidence of grooming and crawling showed no consistent seasonal trends. Roost temperature, time of day, and date explained significant amounts of variation in both daily and seasonal activity budgets. Females rested significantly less and were more alert after young were born than before, although time spent grooming and crawling did not differ significantly between the pre- and post-partum periods. Our findings for P. subflavus generally corroborate activity budgets previously reported for the little brown bat (Myotis lucifugus).

scholarly journals Activity budget of Rhinopithecus bieti at Tibet: Effects of day length, temperature and food availability

2010 ◽  
Vol 56 (6) ◽  
pp. 650-659 ◽  
Author(s):  
Zuofu Xiang ◽  
Sheng Huo ◽  
Wen Xiao
Keyword(s):  
Food Availability ◽  
Activity Budget ◽  
Day Length ◽  
Feeding Time ◽  
Activity Budgets ◽  
Rhinopithecus Bieti ◽  
Resting Time ◽  
Positive Functions ◽  
Energy Balances ◽  
Foraging Time

Abstract How animals allocate their time to various activities has significant consequences for their survival because they reflect the different constraints on time-energy balances. Many ecological variables, such as day length, temperature, food availability, are supposed to effect on activity budgets allocation of temperate primates. To examine the potential influence of these three variables, the activity budgets of Rhinopithecus bieti was studied at Xiaochangdu, Tibet from June 2003 to March 2005. Pearson correlations were utilized to assess potential relationships between activity budget and day length, food availability and temperature, and stepwise multiple regressions to identify the priority of resting and other activities (activities besides feeding, moving and resting). Time spent resting and doing "other activities" is positively related to day length, temperature and food availability. No significant correlations were found between feeding/moving time and any of these variables. This suggests that foraging time (feeding + moving) takes priority over rest and other activities. Day length and foraging time (as independent variables) were related to the time spent in the other two activities besides feeding/moving (as dependent variables). Both time spent resting and in "other activities" were highly significant positive functions of day length, with the latter a highly significant negative function of feeding time and moving time. Resting time may therefore be interpreted as taking priority over "other activities" time. These results provide further evidence of the importance of day length, temperature and food availability to seasonal activity budgets .

scholarly journals Microhabitat use and behavior of voles under weasel and raptor predation risk: predator facilitation?

1996 ◽  
Vol 7 (1) ◽  
pp. 30-34 ◽  
Author(s):  
Erkki Korpimaki ◽  
Vesa Koivunen ◽  
Hani Hakkarainen
Keyword(s):  
Predation Risk ◽  
Microhabitat Use ◽  
And Behavior

Seasonal Activity Budgets of Moose in Aspen-Dominated Boreal Forests

1989 ◽  
Vol 53 (2) ◽  
pp. 296 ◽  
Author(s):  
Lyle A. Renecker ◽  
Robert J. Hudson
Keyword(s):  
Boreal Forests ◽  
Seasonal Activity ◽  
Activity Budgets

Microhabitat use, seasonal activity and diet of the snake-eyed skink (Ablepharus kitaibelii fitzingeri) in comparison with sympatric lacertids in Hungary

Biologia ◽  
2007 ◽  
Vol 62 (4) ◽  
Author(s):  
Gábor Herczeg ◽  
Tibor Kovács ◽  
Zoltán Korsós ◽  
János Török
Keyword(s):  
Thermal Inertia ◽  
Bare Soil ◽  
Stomach Content Analysis ◽  
Food Composition ◽  
Generalist Predator ◽  
Microhabitat Use ◽  
Microhabitat Selection ◽  
Seasonal Activity ◽  
Podarcis Muralis ◽  
Lacerta Viridis

AbstractMicrohabitat selection and seasonal activity of the snake-eyed skink, Ablephaus kitaibelii fitzingeri, are compared to the two lacertid lizards (Lacerta viridis and Podarcis muralis) that co-occur in many of its habitats. The food composition of A. k. fitzingeri is also described. Significant differences in microhabitat selection and seasonal activity among the three species were found. The snake-eyed skink was associated with open grasslands, and with a low level of scrub, bare soil and rock cover. The microhabitat preference of L. viridis was quite similar to that of the skink, but with a higher preference for scrub. P. muralis occurred in places with greater rock and bare soil cover, and more scrub than A. k. fitzingeri. Activity of the snake-eyed skink decreased dramatically in summer, probably because of the reduced thermal inertia originating from the extremely small size of this species, but its seasonal activity overlapped with those of the lacertids. Stomach content analysis of the snake-eyed skink suggests that it is a generalist predator of small, mainly flightless arthropod prey. Competition with juvenile lacertids and predation by adult L. viridis are conceivable for the snake-eyed skink.

Modelling correlates of microhabitat use of two sympatric lizards: a model selection approach

2009 ◽  
Vol 59 (1) ◽  
pp. 109-126 ◽  
Author(s):  
Luca Luiselli ◽  
Pierluigi Bombi ◽  
Marco Bologna ◽  
Daniele Salvi
Keyword(s):  
Logistic Regression ◽  
Information Criterion ◽  
Sympatric Species ◽  
Microhabitat Use ◽  
Logistic Regression Models ◽  
Model Selection Approach ◽  
Depth Analysis ◽  
Microhabitat Choice ◽  
Biology Research ◽  
Study Species

AbstractStudies of the ecological characteristics of sympatric species are important for developing and testing ecological theory, but may be of interest also for conservation biology research when the study species are threatened, endemic and with narrow distribution. Here, we studied a particular aspect of the ecology (i.e. microhabitat use) of two sympatric lizards (Archaeolacerta bedriagae, Podarcis tiliguerta) endemic to Sardinia and Corsica (Tyrrhenian islands). We studied this issue by modelling procedures, using field data collected at six study areas in both Sardinia and Corsica. We recorded 18 microhabitat variables for each lizard spot. The variables were entered as independent variables in logistic regression analysis with the presence/absence data for the lizards as the dependent variable, and Akaike Information Criterion was applied to select the best models describing the ecological equation of each study species. In total, we based our modelling approach on 296 individuals of A. bedriagae and 182 of P. tiliguerta. The general logistic regression models revealed that five distinct variables were significantly correlated to the presence/absence of A. bedriagae, and six to that of P. tiliguerta. We found that three variables were important for only P. tiliguerta, two for only A. bedriagae, and three for both species and with an identical sign. We also found some similarities in microhabitat choice between species. Indeed, some variables were always present in the best models of both A. bedriagae and P. tiliguerta. In general, A. bedriagae was more related to spots with large stones and low vegetation than P. tiliguerta, which, on the contrary, choose spots relatively closer to vegetation. The various reasons explaining the observed similarities and differences between species were examined. It is suggested that our modelling procedure may be widely used for studies of lizard community ecology, because it easy to use and allows a more-in-depth analysis than normal 'count approaches'.

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