scholarly journals No island-effect on glucocorticoid levels for a rodent from a near-shore archipelago

PeerJ ◽  
2020 ◽  
Vol 8 ◽  
pp. e8590 ◽  
Author(s):  
Nathan D. Stewart ◽  
Gabriela F. Mastromonaco ◽  
Gary Burness
Keyword(s):  
National Park ◽  
Stress Physiology ◽  
Population Densities ◽  
Island Effect ◽  
Near Shore ◽  
Thousand Islands ◽  
Island Syndrome ◽  
Corticosterone Metabolites ◽  
Stress Biomarker ◽  
Fecal Corticosterone Metabolites

Island rodents are often larger and live at higher population densities than their mainland counterparts, characteristics that have been referred to as “island syndrome”. Island syndrome has been well studied, but few studies have tested for island-mainland differences in stress physiology. We evaluated island syndrome within the context of stress physiology of white-footed mice (Peromyscus leucopus) captured from 11 islands and five mainland sites in Thousand Islands National Park, Ontario, Canada. Stress physiology was evaluated by quantifying corticosterone (a stress biomarker), the primary glucocorticoid in mice, from hair and its related metabolites from fecal samples. White-footed mice captured in this near-shore archipelago did not display characteristics of island syndrome, nor differences in levels of hair corticosterone or fecal corticosterone metabolites compared with mainland mice. We suggest that island white-footed mice experience similar degrees of stress in the Thousand Islands compared with the mainland. Although we did not find evidence of island syndrome or differences in glucocorticoid levels, we identified relationships between internal (sex, body mass) and external (season) factors and our hormonal indices of stress in white-footed mice.

scholarly journals No island-effect on stress for a rodent from a near-shore archipelago

2019 ◽  
Author(s):  
Nathan D Stewart ◽  
Gabriela F Mastromonaco ◽  
Gary Burness
Keyword(s):  
National Park ◽  
Stress Physiology ◽  
Stress Hormone ◽  
Population Densities ◽  
Island Effect ◽  
Near Shore ◽  
Thousand Islands ◽  
Island Syndrome ◽  
Corticosterone Metabolites ◽  
Fecal Corticosterone Metabolites

Island rodents are often larger and live at higher population densities than their mainland counterparts, characteristics that have been referred to as “island syndrome”. Island syndrome has been well studied, but few studies have tested for island-mainland differences in stress physiology. We evaluated island syndrome within the context of stress physiology of white-footed mice (Peromyscus leucopus) captured from islands (n = 11) and mainland sites (n = 5) in Thousand Islands National Park, Ontario, Canada. Stress physiology was evaluated by quantifying corticosterone, the primary glucocorticoid (stress hormone) of rodents, from hair and its related metabolites from fecal samples. White-footed mice captured in this near-shore archipelago did not display characteristics of island syndrome, nor differences in levels of hair corticosterone or fecal corticosterone metabolites compared with mainland mice. We suggest that island white-footed mice experience similar degrees of stress in the Thousand Islands compared with the mainland. Although we did not find evidence of island syndrome or accompanying changes to stress physiology, we identified relationships between internal (sex, body mass) and external (season) factors and our hormonal indices of stress in white-footed mice.

scholarly journals No island-effect on stress for a rodent from a near-shore archipelago

2019 ◽  
Author(s):  
Nathan D Stewart ◽  
Gabriela F Mastromonaco ◽  
Gary Burness
Keyword(s):  
National Park ◽  
Stress Physiology ◽  
Stress Hormone ◽  
Population Densities ◽  
Island Effect ◽  
Near Shore ◽  
Thousand Islands ◽  
Island Syndrome ◽  
Corticosterone Metabolites ◽  
Fecal Corticosterone Metabolites

Island rodents are often larger and live at higher population densities than their mainland counterparts, characteristics that have been referred to as “island syndrome”. Island syndrome has been well studied, but few studies have tested for island-mainland differences in stress physiology. We evaluated island syndrome within the context of stress physiology of white-footed mice (Peromyscus leucopus) captured from islands (n = 11) and mainland sites (n = 5) in Thousand Islands National Park, Ontario, Canada. Stress physiology was evaluated by quantifying corticosterone, the primary glucocorticoid (stress hormone) of rodents, from hair and its related metabolites from fecal samples. White-footed mice captured in this near-shore archipelago did not display characteristics of island syndrome, nor differences in levels of hair corticosterone or fecal corticosterone metabolites compared with mainland mice. We suggest that island white-footed mice experience similar degrees of stress in the Thousand Islands compared with the mainland. Although we did not find evidence of island syndrome or accompanying changes to stress physiology, we identified relationships between internal (sex, body mass) and external (season) factors and our hormonal indices of stress in white-footed mice.

scholarly journals Assessment of the Stress Response in North American Deermice: Laboratory and Field Validation of Two Enzyme Immunoassays for Fecal Corticosterone Metabolites

Animals ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 1120
Author(s):  
Andreas Eleftheriou ◽  
Rupert Palme ◽  
Rudy Boonstra
Keyword(s):  
Adrenocorticotropic Hormone ◽  
Stress Physiology ◽  
Post Injection ◽  
Field Validation ◽  
Wildlife Ecology ◽  
Adrenocortical Activity ◽  
Enzyme Immunoassays ◽  
Fecal Cortisol ◽  
Corticosterone Metabolites ◽  
Fecal Corticosterone Metabolites

Stress physiology is commonly employed in studies of wildlife ecology and conservation. Accordingly, we need robust and suitable methods to measure stress physiology in the field. Fecal cortisol/corticosterone metabolites (FCMs) are now increasingly being used to non-invasively evaluate adrenocortical activity; a measure of stress physiology. However, immunoassays that measure FCMs must be appropriately validated prior to their use and factors that can influence FCMs, such as trap-induced stress, must be considered. Deermice (Peromyscus maniculatus) are widely used in scientific studies so that developing methods that appropriately measure their adrenocortical activity is critical. In the laboratory, we tested the suitability of two enzyme immunoassays (EIAs; a corticosterone EIA, and a group-specific 5α-pregnane-3β,11β,21-triol-20-one EIA) in deermice by challenging individuals with dexamethasone and adrenocorticotropic hormone (ACTH). We found that dexamethasone suppressed FCM levels within ~10 h post injection whereas ACTH increased FCM levels within ~2 h post injection. In the field, we found that FCM levels generally increased with more time in trap confinement when using both EIAs. Although we acknowledge low sample sizes (N = 4), our results validated the two EIAs for use with FCMs from deermice.

scholarly journals Non-Invasive Monitoring of Adrenocortical Activity in Three Sympatric Desert Gerbil Species

Animals ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 75
Author(s):  
Álvaro Navarro-Castilla ◽  
Mario Garrido ◽  
Hadas Hawlena ◽  
Isabel Barja
Keyword(s):  
Small Sample ◽  
Post Injection ◽  
Control Groups ◽  
Treatment Groups ◽  
Adrenocortical Activity ◽  
Non Invasive ◽  
Endocrine Status ◽  
Corticosterone Metabolites ◽  
Small Sample Sizes ◽  
Fecal Corticosterone Metabolites

The study of the endocrine status can be useful to understand wildlife responses to the changing environment. Here, we validated an enzyme immunoassay (EIA) to non-invasively monitor adrenocortical activity by measuring fecal corticosterone metabolites (FCM) in three sympatric gerbil species (Gerbillus andersoni, G. gerbillus and G. pyramidum) from the Northwestern Negev Desert’s sands (Israel). Animals included into treatment groups were injected with adrenocorticotropic hormone (ACTH) to stimulate adrenocortical activity, while control groups received a saline solution. Feces were collected at different intervals and FCM were quantified by an EIA. Basal FCM levels were similar in the three species. The ACTH effect was evidenced, but the time of FCM peak concentrations appearance differed between the species (6–24 h post-injection). Furthermore, FCM peak values were observed sooner in G. andersoni females than in males (6 h and 18 h post-injection, respectively). G. andersoni and G. gerbillus males in control groups also increased FCM levels (18 h and 48 h post-injection, respectively). Despite the small sample sizes, our results confirmed the EIA suitability for analyzing FCM in these species as a reliable indicator of the adrenocortical activity. This study also revealed that close species, and individuals within a species, can respond differently to the same stressor.

Tidal fish connectivity of reef and sea grass habitats in the Indo-Pacific

2007 ◽  
Vol 87 (5) ◽  
pp. 1287-1296 ◽  
Author(s):  
Richard K.F. Unsworth ◽  
James J. Bell ◽  
David J. Smith
Keyword(s):  
Shallow Water ◽  
National Park ◽  
Fish Assemblages ◽  
Fish Fauna ◽  
Subsistence Fisheries ◽  
Tidal State ◽  
Sea Grass ◽  
Water Fish ◽  
Tidal Changes ◽  
Near Shore

The present study considered the influence of the tide on shallow water fish assemblages within the Wakatobi Marine National Park, Indonesia. Timed underwater visual observations were made across a gradient of intertidal to subtidal habitats from near-shore to reef crest at different tidal heights. Transient fish were found to dominate shallow water fish assemblages and the assemblage composition varied with tidal state. Fish assemblages were more diverse and abundant at higher tides in both coral and sea grass habitats, however, this was more pronounced within sea grass habitats. A tidal reduction from ≈2.0m to ≈0.8m (above chart datum) corresponded to a 30% reduction in fish abundance, while species richness also significantly decreased from 13.5 to 10.8 species per standardized timed observation. Fifty fish groups were reported from sea grass habitats with the most abundant being from the Engraulidae family and Lethrinus harak, which form important local subsistence fisheries. This research confirms the importance of tidal changes in structuring the fish fauna of Indonesian sea grass habitats and underlines the connectivity that exists between these habitats and nearby coral reefs.

scholarly journals Changes in number and distribution of hippoptamus (Hippopotamus amphibius) in the Sabie River, Kruger National Park, during the 1992 drought

Koedoe ◽  
1995 ◽  
Vol 38 (2) ◽  
Author(s):  
P.C. Viljoen
Keyword(s):  
Southern Africa ◽  
National Park ◽  
Dry Season ◽  
Kruger National Park ◽  
Population Densities ◽  
Drought Period ◽  
Aerial Surveys ◽  
Hippopotamus Amphibius ◽  
Reduced Flow

The 1991/92 drought in Southern Africa and the effect of the resultant reduced flow of the Sabie River on hippopotami was investigated. Hippopotami are counted annually in the Kruger National Park's (KNP) major rivers as part of the park's monitoring pro- gramme. Two additional aerial surveys were conducted to document changes in hippopotamus population densities in the Sabie River during the drought period. The hippopotamus population decreased during the drought by 12.6 to 672 animals between July 1991 and October 1992. The highest and lowest hippopotamus densities recorded were 11.6 and 2.2 animals/km river length respectively in different river sections. Only 12 hippopotamus mortalities were recorded at the end of the 1992 dry season (October).

scholarly journals Frequent serial fecal corticoid measures from rats reflect circadian and ovarian corticosterone rhythms

2005 ◽  
Vol 184 (1) ◽  
pp. 153-163 ◽  
Author(s):  
S A Cavigelli ◽  
S L Monfort ◽  
T K Whitney ◽  
Y S Mechref ◽  
M Novotny ◽  
...  
Keyword(s):  
Sprague Dawley ◽  
Temporal Acuity ◽  
Non Invasive ◽  
Laboratory Rodents ◽  
Sprague Dawley Rats ◽  
Single Animal ◽  
Invasive Method ◽  
Luteinizing Hormone Surge ◽  
Corticosterone Metabolites ◽  
Fecal Corticosterone Metabolites

The circadian glucocorticoid rhythm provides important information on the functioning of the hypothalamic-pituitary-adrenal axis in individuals. Frequent repeated blood sampling can limit the kinds of studies conducted on this rhythm, particularly in small laboratory rodents that have limited blood volumes and are easily stressed by handling. We developed an extraction and assay protocol to measure fecal corticosterone metabolites in repeated samples collected from undisturbed male and female adult Sprague–Dawley rats. This fecal measure provides a non-invasive method to assess changes in corticosterone within a single animal over time, with sufficient temporal acuity to quantify several characteristics of the circadian rhythm: e.g. the nadir, acrophase, and asymmetry (saw-tooth) of the rhythm. Males excreted more immunoreactive fecal corticoids than did females. Across the estrous cycle, females produced more fecal corticoids on proestrus (the day of the preovulatory luteinizing hormone surge) than during estrus or metestrus. These results establish a baseline from which to study environmental, psychological, and physiological disturbances of the circadian corticosterone rhythm within individual rats.

Surfacing, Voicing and Signalling Freedom in Relational Performance: Cheryl L’Hirondelle and Camille Turner’s Freedom Tours

Public ◽  
2021 ◽  
Vol 32 (64) ◽  
pp. 23-31
Author(s):  
Tania Willard
Keyword(s):  
Indigenous People ◽  
National Park ◽  
Temporal Space ◽  
Thousand Islands ◽  
Colonial Histories ◽  
Maple Sap

The marking of colonial narratives mapped as histories onto Canada are reinforced on almost every boat, train, or rail tour in Canada. In Freedom Tours (2017) for LandMarks2017/Répéres2017, by artists Cheryl L’Hirondelle and Camille Turner the artists disrupted these entrenched histories hosting two sailings with tour narration. Thes narrated tours featured narratives that stemmed from Cree worldview and Caribbean diasporic perspectives. In L’Hirondelle and Turner’s work they built an architecture of songs unsung and stories untold in a temporal space- a boat tour in the waters in and around the Thousand Islands National Park. In this text I revisit the process of working with these artists to reveal the ways in which their work while being joyous also signaled the ways in which colonial histories drown out Indigenous, Black and People of Colour narratives in Canada. The historic settler alteration of waterways and borders within the Thousand Islands National Park has meant that some islands, previously visited by Indigenous people to harvest maple sap, are no longer above water. In this paper I want to be that island resurfacing sweet syrup, rising in these unstable waters to offer truths to Canada’s colonial narrative.

THE DISTRIBUTION AND LIFE HISTORIES OF THE CADDIS FLIES OF WASKESIU LAKE, SASKATCHEWAN

1943 ◽  
Vol 75 (10) ◽  
pp. 191-198 ◽  
Author(s):  
D. J. Milne
Keyword(s):  
National Park ◽  
Life Histories ◽  
Caddis Flies ◽  
Near Shore ◽  
General Program ◽  
Prince Albert National Park

A study of the caddis flies of Waskesiu Lake was carried out during the summer of 1940 as part of the general program of limnological investigations which have been conducted in Prince Albert National Park, Saskatchewan, since 1928. The importance of caddis flies in the ecology of the lake had been recognized since they provide much food for fish in the near shore reginn.

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