Skip header and navigation

Refine By

13 records – page 1 of 2.

[Adaptive features of the ecology and annual cycle of the willow warbler (Phylloscopus trochilus L.) at the northern boundary of the Siberian part of the range].

https://arctichealth.org/en/permalink/ahliterature261514
Source
Izv Akad Nauk Ser Biol. 2014 Nov-Dec;(6):605-15
Publication Type
Article
Author
V N Ryzhanovskii
Source
Izv Akad Nauk Ser Biol. 2014 Nov-Dec;(6):605-15
Language
Russian
Publication Type
Article
Keywords
Adaptation, Physiological
Animal Migration
Animals
Climate change
Cold Climate
Feathers - anatomy & histology - physiology
Female
Flight, Animal - physiology
Male
Molting - physiology
Passeriformes - growth & development - physiology
Population Dynamics
Seasons
Siberia
Abstract
The ecology of the willow warbler in the north of Western Siberia is considered, and the adaptations that enable the spread of this species to the Subarctic are analyzed. It is established that one of the key factors that caused the change in the range of this species is the northward distribution of shrubs and, hence, the biomass of insects (available food items of these birds).
PubMed ID
25739309 View in PubMed
Less detail

Breeding on the extreme edge: Modulation of the adrenocortical response to acute stress in two High Arctic passerines.

https://arctichealth.org/en/permalink/ahliterature261017
Source
J Exp Zool A Ecol Genet Physiol. 2015 Mar 10;
Publication Type
Article
Date
Mar-10-2015
, the stress response was strongest at arrival and least robust during molt in male snow buntings. Snow bunting females had higher baseline but similar stress- induced corticosterone levels compared to males. Modification of the stress response was not due to adrenal insensitivity, but likely regulated
  1 document  
Author
Brian G Walker
Simone L Meddle
L Michael Romero
Meta M Landys
Jeroen Reneerkens
John C Wingfield
Source
J Exp Zool A Ecol Genet Physiol. 2015 Mar 10;
Date
Mar-10-2015
Language
English
Geographic Location
Greenland
Publication Type
Article
File Size
330198
Keywords
Animal Migration
Physiology
Animals
Arctic Regions
Adrenocorticotropic Hormone
Cold Climate
Corticosterone
Female
Greenland
Male
Molting
Reproduction
Songbirds
Species Specificity
Stress
Pharmacology
Abstract
Arctic weather in spring is unpredictable and can also be extreme, so Arctic-breeding birds must be flexible in their breeding to deal with such variability. Unpredictability in weather conditions will only intensify with climate change and this in turn could affect reproductive capability of migratory birds. Adjustments to coping strategies are therefore crucial, so here we examined the plasticity of the adrenocorticotropic stress response in two Arctic songbird species-the snow bunting (Plectrophenax nivalis) and Lapland longspur (Calcarius lapponicus)-breeding in northwest Greenland. Across the breeding season, the stress response was strongest at arrival and least robust during molt in male snow buntings. Snow bunting females had higher baseline but similar stress-induced corticosterone levels compared to males. Modification of the stress response was not due to adrenal insensitivity, but likely regulated at the anterior pituitary gland. Compared to independent nestlings and adult snow buntings, parental-dependent chicks had a more robust stress response. For Lapland longspurs, baseline corticosterone was highest at arrival in both male and females, and arriving males displayed a higher stress response compared to arriving females. Comparison of male corticosterone profiles collected at arrival in Greenland (76°N) and Alaska (67-71°N;) reveal that both species have higher stress responses at the more northern location. Flexibility in the stress response may be typical for birds nesting at the leading edges of their range and this ability will become more relevant as global climate change results in major shifts of breeding habitat and phenology for migratory birds. J. Exp. Zool. 9999A: 1-10, 2015. Copyright © 2015 Wiley Periodicals, Inc.
PubMed ID
25757443 View in PubMed
Documents
Less detail

Flight feather moult drives minimum daily heart rate in wild geese.

https://arctichealth.org/en/permalink/ahliterature303125
Source
Biol Lett. 2018 11 28; 14(11):
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Date
11-28-2018
Author
Steven J Portugal
Craig R White
Jonathan A Green
Patrick J Butler
Author Affiliation
School of Biological Sciences, Royal Holloway, University of London, Egham TW20 0EX, UK steve.portugal@rhul.ac.uk.
Source
Biol Lett. 2018 11 28; 14(11):
Date
11-28-2018
Language
English
Publication Type
Journal Article
Research Support, Non-U.S. Gov't
Keywords
Animals
Feathers - growth & development
Female
Flight, Animal
Geese - growth & development - physiology
Heart rate
Male
Molting
Norway
Abstract
Waterfowl undergo an annual simultaneous flight-feather moult that renders them flightless for the duration of the regrowth of the flight feathers. In the wild, this period of flightlessness could restrict the capacity of moulting birds to forage and escape predation. Selection might therefore favour a short moult, but feather growth is constrained and presumably energetically demanding. We therefore tested the hypothesis that for birds that undergo a simultaneous flight-feather moult, this would be the period in the annual cycle with the highest minimum daily heart rates, reflecting these increased energetic demands. Implantable heart rate data loggers were used to record year-round heart rate in six wild barnacle geese (Branta leucopsis), a species that undergoes a simultaneous flight-feather moult. The mean minimum daily heart rate was calculated for each individual bird over an 11-month period, and the annual cycle was divided into seasons based on the life-history of the birds. Mean minimum daily heart rate varied significantly between seasons and was significantly elevated during wing moult, to 200 ± 32 beats min-1, compared to all other seasons of the annual cycle, including both the spring and autumn migrations. The increase in minimum daily heart rate during moult is likely due to feather synthesis, thermoregulation and the reallocation of minerals and protein.
PubMed ID
30487260 View in PubMed
Less detail

Hormone, vitamin and contaminant status during the moulting/fasting period in ringed seals (Pusa [Phoca] hispida) from Svalbard.

https://arctichealth.org/en/permalink/ahliterature98859
Source
Comp Biochem Physiol A Mol Integr Physiol. 2010 Jan;155(1):70-6
Publication Type
Article
Date
Jan-2010
Author
Heli Routti
Bjørn Munro Jenssen
Christian Lydersen
Christina Bäckman
Augustine Arukwe
Madeleine Nyman
Kit M Kovacs
Geir Wing Gabrielsen
Author Affiliation
Norwegian Polar Institute, Polar Environmental Centre, 9296 Tromsø, Norway. heli.routti@npolar.no
Source
Comp Biochem Physiol A Mol Integr Physiol. 2010 Jan;155(1):70-6
Date
Jan-2010
Language
English
Publication Type
Article
Keywords
Animals
Fasting - blood - metabolism - physiology
Female
Health status
Hormones - analysis - blood - metabolism
Liver - chemistry - metabolism
Male
Molting - genetics - physiology
Phoca - blood - genetics - metabolism - physiology
Seasons
Svalbard
Thyroid Hormone Receptors beta - genetics - metabolism
Vitamins - analysis - blood - metabolism
Water Pollutants, Chemical - analysis - blood
Abstract
This study investigates the potential effects of moulting, and the concomitant period of fasting undertaken by ringed seals, on hormone, vitamin and contaminant status in adult animals in a population from Svalbard, Norway, which has relatively low contaminant levels. Concentrations of circulating total and free thyroxine and triiodothyronine, circulating and hepatic vitamin A, hepatic persistent organic pollutants and their circulating hydroxyl metabolites were higher in moulting seals compared to pre-moulting seals. The opposite trend was observed for body condition, circulating calcitriol levels and hepatic mRNA expression of thyroid hormone receptor beta. No differences were observed for circulating or hepatic vitamin E levels or hepatic mRNA expressions for deioidinase 1 or 2, or retinoic acid receptor alpha between the two seal groups. The observed differences are likely the result of increased metabolic rates required during moulting to maintain thermal balance and replace the pelage, in combination with mobilization of lipid soluble compounds from blubber stores during the fasting period that is associated with moulting. The present study shows that contaminant levels and their relationships with physiological or endogenous variables can be highly confounded by moulting/fasting status. Thus, moulting status and body condition should be taken into consideration when using variables related to thyroid, calcium or vitamin A homeostasis as biomarkers for contaminant effects.
PubMed ID
19800979 View in PubMed
Less detail

Mercury distribution in the skin of beluga (Delphinapterus leucas) and narwhal (Monodon monoceros) from the Canadian Arctic and mercury burdens and excretion by moulting.

https://arctichealth.org/en/permalink/ahliterature6608
Source
Sci Total Environ. 2005 Dec 1;351-352:333-43
Publication Type
Article
Date
Dec-1-2005
Author
R. Wagemann
H. Kozlowska
Author Affiliation
Department of Fisheries and Oceans, Central and Arctic Region, Freshwater Institute, 501 University Crescent, Winnipeg, Manitoba, Canada R3T 2N6.
Source
Sci Total Environ. 2005 Dec 1;351-352:333-43
Date
Dec-1-2005
Language
English
Publication Type
Article
Keywords
Adipose Tissue - chemistry - metabolism
Animals
Arctic Regions
Beluga Whale - growth & development - metabolism
Canada
Environmental monitoring
Food Contamination
Humans
Mercury - analysis - metabolism
Molting
Muscles - chemistry - metabolism
Research Support, Non-U.S. Gov't
Risk assessment
Skin - chemistry - growth & development - metabolism
Water Pollutants, Chemical - analysis - metabolism
Whales - growth & development - metabolism
Abstract
Beluga and narwhal skin as a whole (in Inuktitut known as "muktuk") is considered to be a delicacy by native Canadian and Greenland people. Individual strata of the skin, and muscle from 27 beluga from the western, and 20 narwhal from the eastern Canadian Arctic, were analyzed for mercury and the thickness and density of each skin layer was measured. Mercury was not uniformly distributed in the skin, but increased outwardly with each layer. The concentration was only 0.29 and 0.16 microg/g (wet wt) in the innermost layer (dermis) of belugas and narwhal respectively, and 1.5 and 1.4 microg/g (wet wt) in the outermost layer (degenerative epidermis) of beluga and narwhal, respectively. There was a significant (alpha=0.05) association between age and mercury concentration in each skin layer, the regression coefficients progressively increasing from the inner layer (dermis) to the outer layer: 0.011-0.063 microg/g year-1; 0.034 microg/g year-1 for skin as a whole; 0.054 microg/g year-1 for muscle. The concentration of total mercury was 0.84 and 0.59 microg/g (wet wt) in skin as a whole (muktuk) of beluga and narwhal respectively, and 0.12 and 0.03 microg/g in blubber, respectively. The average, total mercury concentration in muscle tissue was 1.4 and 0.81 microg/g wet wt, in beluga and narwhal respectively, exceeding (except for blubber) the Canadian Government's Guideline (0.5 microg/g wet wt) for fish export and consumption. The skin surface area of an average-size beluga and narwhal was estimated (6.10 and 6.50 m2, respectively), as were excretions of mercury through moulting (13,861 and 6721 microg year-1; 14 and 7 mg year-1) for belugas and narwhal, respectively. The whole-body mercury burden (699,300 microg; 700 mg) for a 1000 kg beluga and its various tissues were estimated, as was the fraction of mercury excreted by moulting (2-0.42% of the whole-body burden). Annual mercury burden increments in beluga skin, muscle and the whole body were estimated (2750; 17,280; 40,00 microg year-1, respectively), using regression coefficients of age on mercury concentration. The annual gross mercury intake via food was estimated (131,400 microg), of which 70% was excreted.
PubMed ID
16271747 View in PubMed
Less detail

Milk intake and energy expenditure of free-ranging northern fur seal, Callorhinus ursinus, pups.

https://arctichealth.org/en/permalink/ahliterature4809
Source
Physiol Biochem Zool. 2002 Jan-Feb;75(1):3-18
Publication Type
Article
Author
M J Donohue
D P Costa
E. Goebel
G A Antonelis
J D Baker
Author Affiliation
University of California, Santa Cruz, CA 95064, USA. Mary.Donohue@noaa.gov
Source
Physiol Biochem Zool. 2002 Jan-Feb;75(1):3-18
Language
English
Publication Type
Article
Keywords
Animal Nutrition
Animals
Animals, Suckling - growth & development - physiology
Body Composition
Body Weight - physiology
Energy Intake - physiology
Energy Metabolism - physiology
Female
Fur Seals - growth & development - physiology
Male
Milk
Molting - physiology
Research Support, U.S. Gov't, Non-P.H.S.
Weight Gain - physiology
Abstract
Milk ingested by mammalian offspring, coupled with offspring's utilization of this energetic investment, influences survival and growth. A number of studies have examined milk intake in otariids, but few have examined milk intake over the entire lactation period, and none has independently measured energy expenditure concurrent with milk intake. We concurrently examined milk intake, field metabolic rate (FMR), and body composition of 41 pups over the entire lactation interval in 1995 and 1996 on St. Paul Island, Alaska. One hundred two metabolic measurements were obtained with isotope dilution methods. Mean milk intake did not differ annually but increased with age and mass, ranging from 3,400+/-239 to 6,780+/-449 (+/-SE) mL per suckling bout. Milk energy consumption did not vary with age on a mass-specific basis. No differences were detected in milk volume consumed by male and female pups, either absolutely or on a mass-specific basis. Mass-specific FMR peaked during molting, was lowest postmolt, and did not vary by sex. Pups in 1995 had lower FMR than pups in 1996 and were also fatter. Mean milk energy utilized for maintenance metabolism decreased over time from 77% to 43% in 1995 and remained at 71% in 1996. Pup body mass was negatively correlated with the percentage of total body water and positively correlated with the percentage of total body lipid (TBL). Pups increased the percentage of TBL from 16% to 37%. Northern fur seal pups increased energy intake over lactation, while concurrent changes in body composition and pelage condition resulted in mass-specific metabolic savings after the molt.
PubMed ID
11880973 View in PubMed
Less detail

Phodopus campbelli detect reduced photoperiod during development but, unlike Phodopus sungorus, retain functional reproductive physiology.

https://arctichealth.org/en/permalink/ahliterature80468
Source
Reproduction. 2006 Oct;132(4):661-70
Publication Type
Article
Date
Oct-2006
Author
Timonin Mary E
Place Ned J
Wanderi Esther
Wynne-Edwards Katherine E
Author Affiliation
Department of Biology, Queen's University, Kingston, Ontario, Canada K7L 3N6.
Source
Reproduction. 2006 Oct;132(4):661-70
Date
Oct-2006
Language
English
Publication Type
Article
Keywords
Animals
Cricetinae
Epididymis - anatomy & histology
Female
Leptin - blood
Male
Molting
Organ Size
Ovary - anatomy & histology
Phodopus - anatomy & histology - physiology
Photoperiod
Prolactin - blood
Reproduction - physiology
Seasons
Sexual Maturation
Species Specificity
Testis - anatomy & histology
Testosterone - blood
Uterus - anatomy & histology
Vagina - anatomy & histology
Abstract
Golden (Mesocricetus auratus) and Siberian (Phodopus sungorus) hamsters are widely used as animal models for seasonal reproduction; but M. auratus shows no developmental delay in short days until after sexual maturity, whereas P. sungorus juveniles delay development in short days. As the photoperiodic response of Phodopus campbelli is not well established, litters of the two Phodopus species were gestated and reared under long days (14 h light:10 h darkness) or short days (10 h light:14 h darkness) until 70 days of age. As expected, under short photoperiod P. sungorus showed reduced body, testes, epididymides, uterus, and ovary weight; antral follicles and corpora lutea were absent and vaginae remained closed. Animals moulted to winter pelage, and low concentrations of each of leptin, testosterone, and prolactin were present in male serum. Phodopus campbelli juveniles also responded to the short photoperiod as measured by reduced body, testes, epididymides, and ovary weight. The summer pelage persisted. However, both sexes of P. campbelli developed functional reproduction under 10 h light:14 h darkness. All females had a patent vagina by 10 weeks; ovaries contained antral follicles and corpora lutea, and uteri were not reduced in weight. In males, the concentrations of testosterone, leptin, and prolactin were not reduced by short photoperiod. Developmental patterns in the three species of hamster, therefore, differ and are not predicted by relatedness or latitude of origin. Other ecological traits, such as predictability of summer rainfall, ambient temperature, and differential responses to social cues might be important.
PubMed ID
17008477 View in PubMed
Less detail

Plasma biochemistry values in emperor geese (Chen canagica) in Alaska: comparisons among age, sex, incubation, and molt.

https://arctichealth.org/en/permalink/ahliterature88521
Source
J Zoo Wildl Med. 2009 Jun;40(2):321-7
Publication Type
Article
Date
Jun-2009
Author
Franson J Christian
Hoffman David J
Schmutz Joel A
Author Affiliation
U.S. Geological Survey, National Wildlife Health Center, 6006 Schroeder Road, Madison, Wisconsin 53711, USA. jfranson@usgs.gov
Source
J Zoo Wildl Med. 2009 Jun;40(2):321-7
Date
Jun-2009
Language
English
Publication Type
Article
Keywords
Age Factors
Alaska
Animals
Animals, Newborn - blood
Blood Chemical Analysis - veterinary
Female
Geese - blood
Male
Molting - physiology
Reference Values
Reproduction - physiology
Seasons
Sex Factors
Abstract
Reduced populations of emperor geese (Chen canagica), a Bering Sea endemic, provided the need to assess plasma biochemistry values as indicators of population health. A precursory step to such an investigation was to evaluate patterns of variability in plasma biochemistry values among age, sex, and reproductive period. Plasma from 63 emperor geese was collected on their breeding grounds on the Yukon-Kuskokwim Delta in western Alaska, USA. The geese sampled included 18 incubating adult females captured, in mid June, on their nests by using bow nets, and 30 adults and 15 goslings captured in corral traps in late July and early August, when the adults were molting their wing feathers and the goslings were 5-6 weeks old. Plasma was evaluated for 15 biochemical parameters, by comparing results among age, sex, and sampling period (incubation versus wing-feather molt). Ten of the 15 biochemical parameters assayed differed among adults during incubation, the adults during molt, and the goslings at molt, whereas sex differences were noted in few parameters.
PubMed ID
19569480 View in PubMed
Less detail

Reference Intervals for Serum Biochemistries of Molting Pacific Black Brant ( Branta bernicla nigricans) in Northern Alaska, USA.

https://arctichealth.org/en/permalink/ahliterature289493
Source
J Wildl Dis. 2017 04; 53(2):417-419
Publication Type
Journal Article
Research Support, U.S. Gov't, Non-P.H.S.
Date
04-2017
Author
J Christian Franson
Paul L Flint
Joel A Schmutz
Author Affiliation
1 US Geological Survey, National Wildlife Health Center, 6006 Schroeder Road, Madison, Wisconsin 53711, USA.
Source
J Wildl Dis. 2017 04; 53(2):417-419
Date
04-2017
Language
English
Publication Type
Journal Article
Research Support, U.S. Gov't, Non-P.H.S.
Keywords
Alaska
Animals
Anseriformes
Ecosystem
Geese
Molting
Abstract
We determined reference intervals for nine serum biochemistries in samples from 329 molting, after-hatch-year, Pacific Black Brant ( Branta bernicla nigricans) in Alaska, US. Cholesterol and nonesterified fatty acids differed by sex, but no other differences were noted.
PubMed ID
28094610 View in PubMed
Less detail

Reference Intervals for Serum Biochemistries of Molting Pacific Black Brant ( Branta bernicla nigricans) in Northern Alaska, USA.

https://arctichealth.org/en/permalink/ahliterature289651
Source
J Wildl Dis. 2017 04; 53(2):417-419
Publication Type
Journal Article
Research Support, U.S. Gov't, Non-P.H.S.
Date
04-2017
Author
J Christian Franson
Paul L Flint
Joel A Schmutz
Author Affiliation
1 US Geological Survey, National Wildlife Health Center, 6006 Schroeder Road, Madison, Wisconsin 53711, USA.
Source
J Wildl Dis. 2017 04; 53(2):417-419
Date
04-2017
Language
English
Publication Type
Journal Article
Research Support, U.S. Gov't, Non-P.H.S.
Keywords
Alaska
Animals
Anseriformes
Ecosystem
Geese
Molting
Abstract
We determined reference intervals for nine serum biochemistries in samples from 329 molting, after-hatch-year, Pacific Black Brant ( Branta bernicla nigricans) in Alaska, US. Cholesterol and nonesterified fatty acids differed by sex, but no other differences were noted.
PubMed ID
28094610 View in PubMed
Less detail

13 records – page 1 of 2.