scholarly journals Annual Migration Density and Stopover Patterns of Northern Saw-whet Owls (Aegolius acadicus)

The Auk ◽  
2002 ◽  
Vol 119 (4) ◽  
pp. 1154-1161
Author(s):  
David M. Whalen ◽  
Bryan D. Watts

Abstract Northern Saw-whet Owls (Aegolius acadicus) exhibit large fluctuations in annual number of individuals migrating in eastern United States. Underlying large differences in the magnitude of the migration may be important density-dependent effects on body condition and stopover patterns. We investigated such effects using data from saw-whet owls that were trapped and banded during autumn migration at the southern tip of the Delmarva Peninsula (near Cape Charles, Virginia) from 1994 to 2000. Irruptive migration events occurred in 1995 and 1999 when 1,002 and 700 owls were captured, respectively. Capture totals ranged from 22 to 105 owls during five nonirruptive years. Irruptive migration years were dominated by immature owls (82% of captures) and were characterized by low recapture rates (13%) and shorter minimum stopover lengths (median = 5 nights) for all owls. Body masses and body-condition index scores were significantly lower for both immature and adult age classes during years when owl density was very high. During such years, a smaller percentage of owls elected to stopover and, among those that did, individuals in good condition departed sooner than individuals in poor condition. Conversely, during nonirruptive years, adults constituted 67% of captures, recapture rates were nearly 3× higher (35%), and stopover lengths were twice as long (median = 10 nights). Recapture rates were significantly higher for adults (43%) than for immature owls (23%) and initial body condition of adults was positively correlated with their length of stopover. During light migration years, conditions may be conducive for extended residency, particularly for adult owls in good condition. Our results suggest that density-dependence is an important mechanism driving migration and stopover patterns of saw-whet owls.

Vaccines ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 870
Author(s):  
Yuri Perepliotchikov ◽  
Tomer Ziv-Baran ◽  
Musa Hindiyeh ◽  
Yossi Manor ◽  
Danit Sofer ◽  
...  

Response to and monitoring of viral outbreaks can be efficiently focused when rapid, quantitative, kinetic information provides the location and the number of infected individuals. Environmental surveillance traditionally provides information on location of populations with contagious, infected individuals since infectious poliovirus is excreted whether infections are asymptomatic or symptomatic. Here, we describe development of rapid (1 week turnaround time, TAT), quantitative RT-PCR of poliovirus RNA extracted directly from concentrated environmental surveillance samples to infer the number of infected individuals excreting poliovirus. The quantitation method was validated using data from vaccination with bivalent oral polio vaccine (bOPV). The method was then applied to infer the weekly number of excreters in a large, sustained, asymptomatic outbreak of wild type 1 poliovirus in Israel (2013) in a population where >90% of the individuals received three doses of inactivated polio vaccine (IPV). Evidence-based intervention strategies were based on the short TAT for direct quantitative detection. Furthermore, a TAT shorter than the duration of poliovirus excretion allowed resampling of infected individuals. Finally, the method documented absence of infections after successful intervention of the asymptomatic outbreak. The methodologies described here can be applied to outbreaks of other excreted viruses such as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), where there are (1) significant numbers of asymptomatic infections; (2) long incubation times during which infectious virus is excreted; and (3) limited resources, facilities, and manpower that restrict the number of individuals who can be tested and re-tested.


Author(s):  
Jeonggyo Yoon ◽  
Minsun Kang ◽  
Jaehun Jung ◽  
Min Jae Ju ◽  
Sung Hwan Jeong ◽  
...  

Humidifier disinfectant (HD) is a household biocidal product used in humidifier water tanks to prevent the growth of microorganisms. In 2011, a series of lung injury cases of unknown causes emerged in children and pregnant women who had used HD in Korea. This study investigated changes in the nationwide number of cases of humidifier disinfectant-associated lung injury (HDLI) in concordance with nationwide HD consumption using data covering the entire Korean population. More than 25 kinds of HD products were sold between 1994 and 2011. The number of diagnosed HDLI, assessed by S27.3 (other injuries of lungs) of the Korea National Health Insurance Service (NHIS) data, sharply increased by 2005, subsequently decreased after 2005, and almost disappeared after 2011 in concordance with the annual number of HD sales. The number of self-reported HDLIs, assessed using data from all suspected HDLI cases registered in the Korea Ministry of Environment, changed with the annual number of HD sales, with a delay pattern, potentially induced by the late awareness of lung injury diseases. The present study suggests that changes in the nationwide annual consumption of HD products were consistent with changes in the annual number of HDLI cases in Korea.


2012 ◽  
Vol 39 (4) ◽  
pp. 301 ◽  
Author(s):  
Gina M. Morgan ◽  
Travis E. Wilcoxen ◽  
Michelle A. Rensel ◽  
Stephan J. Schoech

Context Anthropogenic disturbances induce physiological and behavioural responses in numerous species. The negative effects of human disturbance are of special concern to threatened and endangered species. Aims The present study aims to compare physiological stress measures and reproductive success of Florida scrub-jays (Aphelocoma coerulescens) living near roads with jays that live away from roads. Specifically, it aims to test whether roads are stressful. Methods We assessed physiological measures that can serve as indicators of ‘stress’ to determine whether a highway that bisects our study site had physiological effects on adult male Florida scrub-jays. We captured male breeders from three territory types, including scrub habitat that (1) bordered a highway with a grassy shoulder that created an ‘edge’ habitat (roadside), (2) bordered human-maintained habitat (a plowed firebreak of sand with adjacent pasture) that served as a control for the edge-effect of the road (pasture) and (3) contained only natural scrub habitat (interior). We measured baseline concentrations of the stress hormone corticosterone (CORT), body mass, and a suite of longitudinal body measures to generate a body condition index in males from each territory type over three breeding seasons. Key results Roadside jays had greater body mass than did interior and pasture jays, although there were no differences in overall baseline CORT concentrations or body condition among territory classes. There was no difference in clutch initiation date or size and nestling and independent-young survival. Conclusions Our results suggest that the road through our study site has physiological effects on Florida scrub-jays; however, there is mixed evidence as to whether it acts as a chronic stressor. Implications Our findings provide evidence that roads and road-associated disturbance has neutral or potentially beneficial physiological effects of roads on Florida scrub-jays. Knowledge of these effects of roads and disturbance on jays will hopefully provide additional opportunities to improve conservation of this species.


2011 ◽  
Vol 11 (9) ◽  
pp. 2407-2417 ◽  
Author(s):  
L. P. Almeida ◽  
Ó. Ferreira ◽  
M. I. Vousdoukas ◽  
G. Dodet

Abstract. This work investigates historical variation and trends in storm climate for the South Portugal region, using data from wave buoy measurements and from modelling, for the period 1952 to 2009. Several storm parameters (annual number of storms; annual number of days with storms; annual maximum and mean individual storm duration and annual 99.8th percentile of significant wave height) were used to analyse: (1) historical storminess trends; (2) storm parameter variability and relationships; and (3) historical storminess and its relationship to the North Atlantic Oscillation (NAO). No statistically significant linear increase or decrease was found in any of the storm parameters over the period of interest. The main pattern of storm characteristics and extreme wave heights is an oscillatory variability with intensity peaks every 7–8 yr, and the magnitude of recent variations is comparable with that of variations observed in the earlier parts of the record. In addition, the results reveal that the NAO index is able to explain only a small percentage of the variation in storm wave height, suggesting that more local factors may be of importance in controlling storminess in this region.


Author(s):  
Danise Benatti ◽  
Luis Felipe Andrietti ◽  
José Flávio Cândido Júnior ◽  
Alexandre Vogliotti ◽  
Marcela Figueirêdo Duarte Moraes ◽  
...  

Abstract Rodents are small mammals that can be parasitized by various helminths. This study aimed to identify and describe the ecological indicators of infection in rodents captured in fragments of the Atlantic Forest in the western region of Paraná State, Brazil. Sixty-eight specimens of five rodent species were collected, necropsied, and inspected in search of helminths. The parasites were stored in 70% ethanol, morphologically identified, and counted for calculation of infection indicators. Fourteen species of helminths and one species of Crustacea were recorded: ten in Akodon montensis, four in Mus musculus, two in Thaptomys nigrita, two in Oligoryzomys nigripes, and one in Euryoryzomys russatus. The registered species of parasites were: Rodentolepis akodontis, Angiostrongylus sp., Protospirura numidica criceticola, Trichuris navonae, Syphacia alata, Syphacia criceti, Syphacia evaginata, Trichofreitasia lenti, Stilestrongylus aculeata, Stilestrongylus eta, Stilestrongylus gracielae, Stilestrongylus franciscanus, Stilestrongylus moreli, Stilestrongylus sp., and Pentastomida gen. sp. A positive correlation between the intensity of infection of T. navonae and T. lenti was observed with the body condition index of the host A. montensis. For all species, this study represents a new register of locality, and for eight of them a new host.


2016 ◽  
Vol 2 (1) ◽  
pp. 67-76
Author(s):  
Yasser Ahmed ◽  
Armin Fabritzek ◽  
Neviaty P. Zamani ◽  
Karen Von Juterzenka ◽  
Mark Lenz

Pergerakan organisme dipengaruhi oleh penyebaran alami dan aktivitas manusia.Beberapa spesies yang terbawa, memiliki sebaran yang melebihi distribusi batas normal oleh pengaruh tertentu (vector).Penelitian ini melakukan pengujian pada skala laboratorium untuk melihat survival rate yang terkait dengan body condition index selama diberikan stress suhu yang terkait perubahan iklim dan ini juga dapat dijadikan sebagai simulasi transportasi kapal, sehingga dapat diketahui pergerakan organisme.Distribusi organisme tersebut mempengaruhi kemampuan bertahan hidupselama transportasi.Oleh karena itu, perlu dilakukan penelitian dengan mengekspose grup pra-stress dan grup non stress sebelum masuk ke fase stress dan membandingkan survival rate dan body condition index (BCI) pada organisme tersebut. Organisme yang dipilih adalah Kerang Hijau (P. viridis) dengan menggunakan stress suhu.Pengukuran respon variabel dari organisme tersebut yaitu survival rate dan body condition index (BCI).Penelitian ini menunjukkan bahwa survival rate dan body condition index memiliki korelasi linier.


2007 ◽  
Vol 55 (4) ◽  
pp. 249 ◽  
Author(s):  
Louise Mortimer ◽  
Alan Lill

Some birds facing energy ‘bottlenecks’ display elevated oxidative metabolism and oxygen delivery to tissues and could be particularly susceptible to chronic stress. We examined whether there was evidence for such trends in little penguins (Eudyptula minor) over the period from breeding to the post-moulting stage and particularly during the onshore moult-fast. Penguin parents contribute equally to incubation, brooding and brood provisioning. A few weeks post-breeding, adults undergo a protracted, terrestrial moult-fast and then make brief visits to the colony during the post-moulting stage. Provisioning nestling(s) and moulting could theoretically be particularly energetically and nutritionally demanding. We determined for adults whether mass, a body condition index and blood parameters influencing vascular oxygen carrying capacity (hematocrit, Hct; whole blood haemoglobin, Hb) and indicating chronic stress (leukocyte count, WBC; heterophil/lymphocyte ratio, H/L) varied from August to May in a manner reflecting likely variation in energy and nutrient demand. Female mass and body condition index decreased significantly between the incubation and guard stages, before returning to incubation levels between the guard and post-guard nestling stages. Both parameters declined to their lowest levels between the post-guard and moult stages, before increasing to levels comparable with those during nestling care between the moult and post-moult stages. Blood parameters in both sexes exhibited temporal variation similar to that in female mass and body condition index, declining to their lowest levels during moult and increasing after the moult to levels comparable with those during breeding. Results indicated that the period of most intense provisioning of nestlings was associated with a decrease in blood oxygen carrying capacity, but no pronounced change in chronic stress indicators. However, the penguin’s moult-fast involved a loss of female body condition and, in both sexes, a reduction in body mass, vascular oxygen carrying capacity and possibly specific immune competence. Thus, regulation of human disturbance in accessible little penguin colonies may be particularly important during moult.


<em>Abstract</em>.—U.S. Game and Fish agencies and farm-pond owners throughout the United States use commercially produced channel catfish <em>Ictalurus punctatus </em>fingerlings transported from the southern United States for supplemental stocking. We conducted six trials to examine whether pathogen load, body condition, and select environmental factors influence fingerling survival following transport and cage stocking. Fingerlings were sampled prior to stocking and weekly for the following 3 weeks. Weights and lengths were measured, and a relative condition index was used to quantify body condition. Skin scrapings and gill clippings were examined microscopically for pathogens, and posterior kidney was assayed for <em>Aeromonas hydrophila</em>. Mortality was either less than 10% (four trials) or catastrophic (two trials). A Columnaris disease epizootic was associated with ~50% mortality in one trial, and a red sore disease epizootic was associated with ~80% mortality in another. Body condition or other pathogens, present initially or acquired in study ponds, were not associated with high mortality. The first week appears to be critical for the survival of channel catfish fingerlings following transport.


Author(s):  
Mariusz Wesołowski ◽  
Paweł Iwanowski

Many factors have an impact on flight operation safety and air transport participants life. This article presents one of them, which is maintenance of the airport infrastructure in a good condition, with proper infrastructure management, in particular of cash and human resources. At the beginning of the article, attention is paid to the aspect of safety and human life in air transport. Also, an overview of world experience in the field of assessment of the technical condition of airport pavements was presented, including the standard method of the Pavement Condition Index (PCI) estimation. Then, the authors propose an innovative method of assessing the condition of airport pavements based on the Airfield Pavement Condition Index (APCI), taking into account, apart from the extent of surface damage, such parameters as load capacity, evenness, roughness, and bond strength. This approach gives a broader picture of the actual condition of the airport pavement, which has a great importance on flight operation safety, including passengers and cruel life. Next the described research method is experimentally verified in real conditions at Polish airports. Finally, an example of using the APCI method in the assessment of selected airport pavements from Polish airports is presented. The results of tests performed on five functional elements of a military airfield are presented. A satisfactory result is obtained for three elements, an adequate—for two.


2010 ◽  
Vol 31 (4) ◽  
pp. 558-562 ◽  
Author(s):  
Rodica Plăiaşu ◽  
Tibor Hartel ◽  
Raluca Ioana Băncilă ◽  
Dan Cogălniceanu ◽  
Joost Smets

AbstractBody condition is important because it is correlated with population and habitat quality parameters. Since the direct measurements are either lethal or unreliable, a wide range of non-lethal body condition indices has been proposed. The aim of our study was to apply and compare three body condition indices (Fulton's index, relative body condition mass index and residual index) using body size indicator – body mass data for 24 populations of the yellow bellied toad (Bombina variegata). The condition index should be independent of body size indicator, in this case snout vent length (SVL). Therefore we tested all three indices for the statistical independence of SVL and for the normality of distribution. Fulton's index violated the independence assumption, whereas the relative body condition mass index did not have a normal distribution. Residual index was found both independent of SVL and normally distributed. Moreover, the residual index highlighted biological significant differences on the basis of altitude and season. Our results recommend the residual index as a useful tool in amphibian monitoring and conservation.


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