Conservation Physiology最新文献

{"title":"Maternal diet influences fecundity in a freshwater turtle undergoing population decline.","authors":"Kristen Petrov, James U Van Dyke, Arthur Georges, Claudia Keitel, Ricky-John Spencer","doi":"10.1093/conphys/coae033","DOIUrl":"10.1093/conphys/coae033","url":null,"abstract":"<p><p>Food availability determines the amount of energy animals can acquire and allocate to reproduction and other necessary functions. Female animals that are food limited thus experience reduced energy available for reproduction. When this occurs, females may reduce frequency of reproductive events or the number or size of offspring per reproductive bout. We assessed how maternal diet affects reproductive output in adult female Murray River short-necked turtles, <i>Emydura macquarii,</i> from four wetlands in Victoria. We previously found that turtle diets differ in the composition of plants and animals between our study wetlands. In this study, we tested whether differences in turtle diet composition (i.e. plants and animals) at these wetlands were associated with differences in clutch mass, individual egg mass, bulk egg composition and hatching success. We found total clutch mass increased with maternal body size at each site. At sites where filamentous green algae were scarce and <i>E. macquarii</i> were carnivorous, females produced smaller clutches relative to body size compared to females from sites where algae were abundant, and turtles were more herbivorous. Individual egg mass, bulk egg composition and hatching success did not differ across wetlands. Isotopic analysis revealed significant positive relationships between the carbon and nitrogen isotopes (δ¹³C, δ¹⁵N) of the eggs and those of the mothers, indicating that mothers allocated ratios of carbon and nitrogen isotopes to their eggs similar to those present in their tissues. Our study suggests that at sites where females are more carnivorous due to a relative absence of algae, females produce smaller clutches, but other aspects of their reproduction are not significantly impacted. The reduction in clutch size associated with differences in the availability of dietary plants and animals may have long-term consequences for <i>E. macquarii</i> and other freshwater turtle species that are experiencing population declines.</p>","PeriodicalId":54331,"journal":{"name":"Conservation Physiology","volume":"12 1","pages":"coae033"},"PeriodicalIF":2.7,"publicationDate":"2024-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11129712/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141159167","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Hot climate, hot koalas: the role of weather, behaviour and disease on thermoregulation.","authors":"Valentina S A Mella, Christine E Cooper, Madeline Karr, Andrew Krockenberger, George Madani, Elliot B Webb, Mark B Krockenberger","doi":"10.1093/conphys/coae032","DOIUrl":"10.1093/conphys/coae032","url":null,"abstract":"<p><p>Thermoregulation is critical for endotherms living in hot, dry conditions, and maintaining optimal core body temperature (<i>T</i>_b) in a changing climate is an increasingly challenging task for mammals. Koalas (<i>Phascolarctos cinereus</i>) have evolved physiological and behavioural strategies to maintain homeostasis and regulate their <i>T</i>_b but are thought to be vulnerable to prolonged heat. We investigated how weather, behaviour and disease influence <i>T</i>_b for wild, free-living koalas during summer in north-west New South Wales. We matched <i>T</i>_b with daily behavioural observations in an ageing population where chlamydial disease is prevalent. Each individual koala had similar <i>T</i>_b rhythms (average <i>T</i>_b = 36.4 ± 0.05°C), but male koalas had higher <i>T</i>_b amplitude and more pronounced daily rhythm than females. Disease disrupted the 24-hr circadian pattern of <i>T</i>_b. Koala <i>T</i>_b increased with ambient temperature (<i>T</i>_a). On the hottest day of the study (maximum <i>T</i>_a = 40.8°C), we recorded the highest (<i>T</i>_b = 40.8°C) but also the lowest (<i>T</i>_b = 32.4°C) <i>T</i>_b ever documented for wild koalas, suggesting that they are more heterothermic than previously recognized. This requires individuals to predict days of extreme <i>T</i>_a from overnight and early morning conditions, adjusting <i>T</i>_b regulation accordingly, and it has never been reported before for koalas. The large diel amplitude and low minimum <i>T</i>_b observed suggest that koalas at our study site are energetically and nutritionally compromised, likely due to their age. Behaviour (i.e. tree hugging and drinking water) was not effective in moderating <i>T</i>_b. These results indicate that <i>T</i>_a and koala <i>T</i>_b are strongly interconnected and reinforce the importance of climate projections for predicting the future persistence of koalas throughout their current distribution. Global climate models forecast that dry, hot weather will continue to escalate and drought events will increase in frequency, duration and severity. This is likely to push koalas and other arboreal folivores towards their thermal limit.</p>","PeriodicalId":54331,"journal":{"name":"Conservation Physiology","volume":"12 1","pages":"coae032"},"PeriodicalIF":2.7,"publicationDate":"2024-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11129715/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141159147","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spatiotemporal variation in ecophysiological traits align with high resolution niche modelling in the short-range banded ironstone endemic Aluta quadrata","authors":"Wolfgang Lewandrowski, Emily P Tudor, Hayden Ajduk, Sean Tomlinson, Jason C Stevens","doi":"10.1093/conphys/coae030","DOIUrl":"https://doi.org/10.1093/conphys/coae030","url":null,"abstract":"Defining plant ecophysiological responses across natural distributions enables a greater understanding of the niche that plants occupy. Much of the foundational knowledge of species’ ecology and responses to environmental change across their distribution is often lacking, particularly for rare and threatened species, exacerbating management and conservation challenges. Combining high-resolution species distribution models (SDMs) with ecophysiological monitoring characterized the spatiotemporal variation in both plant traits and their interactions with their surrounding environment for the range-restricted Aluta quadrata Rye &amp; Trudgen, and a common, co-occurring generalist, Eremophila latrobei subsp. glabra (L.S.Sm.) Chinnock., from the semi-arid Pilbara and Gascoyne region in northwest Western Australia. The plants reflected differences in gas exchange, plant health and plant water relations at sites with contrasting suitability from the SDM, with higher performance measured in the SDM-predicted high-suitability site. Seasonal differences demonstrated the highest variation across ecophysiological traits in both species, with higher performance in the austral wet season across all levels of habitat suitability. The results of this study allow us to effectively describe how plant performance in A. quadrata is distributed across the landscape in contrast to a common, widespread co-occurring species and demonstrate a level of confidence in the habitat suitability modelling derived from the SDM in predicting plant function determined through intensive ecophysiology monitoring programmes. In addition, the findings also provide a baseline approach for future conservation actions, as well as to explore the mechanisms underpinning the short-range endemism arid zone systems.","PeriodicalId":54331,"journal":{"name":"Conservation Physiology","volume":"31 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-05-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141151848","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Acclimation of thermal tolerance in juvenile plants from three biomes is suppressed when extremes co-occur","authors":"Rosalie J Harris, Philippa R Alvarez, Callum Bryant, Verónica F Briceño, Alicia M Cook, Andrea Leigh, Adrienne B Nicotra","doi":"10.1093/conphys/coae027","DOIUrl":"https://doi.org/10.1093/conphys/coae027","url":null,"abstract":"Given the rising frequency of thermal extremes (heatwaves and cold snaps) due to climate change, comprehending how a plant’s origin affects its thermal tolerance breadth (TTB) becomes vital. We studied juvenile plants from three biomes: temperate coastal rainforest, desert and alpine. In controlled settings, plants underwent hot days and cold nights in a factorial design to examine thermal tolerance acclimation. We assessed thermal thresholds (Tcrit-hot and Tcrit-cold) and TTB. We hypothesized that (i) desert species would show the highest heat tolerance, alpine species the greatest cold tolerance and temperate species intermediate tolerance; (ii) all species would increase heat tolerance after hot days and cold tolerance after cold nights; (iii) combined exposure would broaden TTB more than individual conditions, especially in desert and alpine species. We found that biome responses were minor compared to the responses to the extreme temperature treatments. All plants increased thermal tolerance in response to hot 40°C days (Tcrit-hot increased by ~3.5°C), but there was minimal change in Tcrit-cold in response to the cold −2°C nights. In contrast, when exposed to both hot days and cold nights, on average, plants exhibited an antagonistic response in TTB, where cold tolerance decreased and heat tolerance was reduced, and so we did not see the bi-directional expansion we hypothesized. There was, however, considerable variation among species in these responses. As climate change intensifies, plant communities, especially in transitional seasons, will regularly face such temperature swings. Our results shed light on potential plant responses under these extremes, emphasizing the need for deeper species-specific thermal acclimation insights, ultimately guiding conservation efforts.","PeriodicalId":54331,"journal":{"name":"Conservation Physiology","volume":"102 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-05-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141151771","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Migratory behaviours are risk-sensitive to physiological state in an elevational migrant.","authors":"Kristin Denryter, Thomas R Stephenson, Kevin L Monteith","doi":"10.1093/conphys/coae029","DOIUrl":"10.1093/conphys/coae029","url":null,"abstract":"<p><p>Accretion of body fat by animals is an important physiological adaptation that may underpin seasonal behaviours, especially where it modulates risk associated with a particular behaviour. Using movement data from male Sierra Nevada bighorn sheep (<i>Ovis canadensis sierrae</i>), we tested the hypothesis that migratory behaviours were risk-sensitive to physiological state (indexed by body fat). Sierra bighorn face severe winter conditions at high elevations and higher predation risk at lower elevations. Given that large body fat stores ameliorate starvation risk, we predicted that having small body fat stores would force animals to migrate to lower elevations with more abundant food supplies. We also predicted that body fat stores would influence how far animals migrate, with the skinniest animals migrating the furthest down in elevation (to access the most abundant food supplies at that time of year). Lastly, we predicted that population-level rates of switching between migratory tactics would be inversely related to body fat levels because as body fat levels decrease, animals exhibiting migratory plasticity should modulate their risk of starvation by switching migratory tactics. Consistent with our predictions, probability of migration and elevational distance migrated increased with decreasing body fat, but effects differed amongst metapopulations. Population-level switching rates also were inversely related to population-level measures of body fat prior to migration. Collectively, our findings suggest migration was risk-sensitive to physiological state, and failure to accrete adequate fat may force animals to make trade-offs between starvation and predation risk. In complex seasonal environments, risk-sensitive migration yields a layer of flexibility that should aid long-term persistence of animals that can best modulate their risk by attuning behaviour to physiological state.</p>","PeriodicalId":54331,"journal":{"name":"Conservation Physiology","volume":"12 1","pages":"coae029"},"PeriodicalIF":2.7,"publicationDate":"2024-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11109817/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141082957","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tolerance threshold of a pelagic species in China to total dissolved gas supersaturation: from the perspective of survival characteristics and swimming ability","authors":"Hongtao Wang, Yuanming Wang, Kefeng Li, Ruifeng Liang, Weiyang Zhao","doi":"10.1093/conphys/coae023","DOIUrl":"https://doi.org/10.1093/conphys/coae023","url":null,"abstract":"Total dissolved gas (TDG) supersaturation downstream of dams can occur in the Yangtze River basin and is known to cause stress and even death in fish. Consequently, it is important to establish tolerance thresholds of endemic fish to protect local aquatic resources. We conducted experiments to assess survival characteristics and swimming ability of bighead carp, an important commercial fish dwelling in the Yangtze River, to evaluate its tolerance threshold to TDG supersaturation. The typical external symptoms of gas bubble trauma (GBT) were observed and the time when the fish lost equilibrium and died were recorded. The results showed that the mortality occurred when TDG level exceeded 125%, with obvious symptoms such as exophthalmos and bubbles on the head. The interval between loss of equilibrium and mortality decreased with an increase in TDG level. Neither exposure time nor TDG level significantly affected the critical swimming speed (Ucrit) of fish exposed to non-lethal exposure (110%, 120% and 125% TDG) over a 7 day period. Significant reductions in Ucrit were found under 130% and 135% TDG conditions when the exposure lasted 52.0 h and 42.9 h, respectively. The Ucrit also significantly decreased after exposure of 1.6 h under 140% TDG condition. Moreover, after exposure to 140% TDG for 39.2 h, 135% TDG for 56.5 h and 130% TDG for 95.9 h, bighead carp were transferred into air saturated water to recover for 24 h or 48 h; however, swimming performance remained impaired. The results of this study indicate that 125% TDG was the highest TDG level where limited mortality was observed and the swimming ability was not impaired, showing that 125% TDG can be set as the tolerance threshold of this species to guide the operation of dams in the Yangtze River Basin.","PeriodicalId":54331,"journal":{"name":"Conservation Physiology","volume":"25 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141058576","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Respiratory acidosis and O_<b>2</b> supply capacity do not affect the acute temperature tolerance of rainbow trout (<i>Oncorhynchus mykiss</i>).","authors":"Daniel W Montgomery, Jennifer Finlay, Stephen D Simpson, Georg H Engelhard, Silvana N R Birchenough, Rod W Wilson","doi":"10.1093/conphys/coae026","DOIUrl":"10.1093/conphys/coae026","url":null,"abstract":"<p><p>The mechanisms that determine the temperature tolerances of fish are poorly understood, creating barriers to disentangle how additional environmental challenges-such as CO₂-induced aquatic acidification and fluctuating oxygen availability-may exacerbate vulnerability to a warming climate and extreme heat events. Here, we explored whether two acute exposures (~0.5 hours or ~72 hours) to increased CO₂ impact acute temperature tolerance limits in a freshwater fish, rainbow trout (<i>Oncorhynchus mykiss</i>). We separated the potential effects of acute high CO₂ exposure on critical thermal maximum (CT_max), caused via either respiratory acidosis (reduced internal pH) or O₂ supply capacity (aerobic scope), by exposing rainbow trout to ~1 kPa CO₂ (~1% or 10 000 μatm) in combination with normoxia or hyperoxia (~21 or 42 kPa O₂, respectively). In normoxia, acute exposure to high CO₂ caused a large acidosis in trout (blood pH decreased by 0.43 units), while a combination of hyperoxia and ~1 kPa CO₂ increased the aerobic scope of trout by 28%. Despite large changes in blood pH and aerobic scope between treatments, we observed no impacts on the CT_max of trout. Our results suggest that the mechanisms that determine the maximum temperature tolerance of trout are independent of blood acid-base balance or the capacity to deliver O₂ to tissues.</p>","PeriodicalId":54331,"journal":{"name":"Conservation Physiology","volume":"12 1","pages":"coae026"},"PeriodicalIF":2.7,"publicationDate":"2024-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11109029/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141082959","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Physiologically informed organismal climatologies reveal unexpected spatiotemporal trends in temperature.","authors":"Aubrey Foulk, Tarik Gouhier, Francis Choi, Jessica L Torossian, Allison Matzelle, David Sittenfeld, Brian Helmuth","doi":"10.1093/conphys/coae025","DOIUrl":"10.1093/conphys/coae025","url":null,"abstract":"<p><p>Body temperature is universally recognized as a dominant driver of biological performance. Although the critical distinction between the temperature of an organism and its surrounding habitat has long been recognized, it remains common practice to assume that trends in air temperature-collected via remote sensing or weather stations-are diagnostic of trends in animal temperature and thus of spatiotemporal patterns of physiological stress and mortality risk. Here, by analysing long-term trends recorded by biomimetic temperature sensors designed to emulate intertidal mussel temperature across the US Pacific Coast, we show that trends in maximal organismal temperature ('organismal climatologies') during aerial exposure can differ substantially from those exhibited by co-located environmental data products. Specifically, using linear regression to compare maximal organismal and environmental (air temperature) climatologies, we show that not only are the magnitudes of body and air temperature markedly different, as expected, but so are their temporal trends at both local and biogeographic scales, with some sites showing significant decadal-scale increases in organismal temperature despite reductions in air temperature, or vice versa. The idiosyncratic relationship between the spatiotemporal patterns of organismal and air temperatures suggests that environmental climatology cannot be statistically corrected to serve as an accurate proxy for organismal climatology. Finally, using quantile regression, we show that spatiotemporal trends vary across the distribution of organismal temperature, with extremes shifting in different directions and at different rates than average metrics. Overall, our results highlight the importance of quantifying changes in the entire distribution of temperature to better predict biological performance and dispel the notion that raw or 'corrected' environmental (and specially air temperature) climatologies can be used to predict organismal temperature trends. Hence, despite their widespread coverage and availability, the severe limitations of environmental climatologies suggest that their role in conservation and management policy should be carefully considered.</p>","PeriodicalId":54331,"journal":{"name":"Conservation Physiology","volume":"12 1","pages":"coae025"},"PeriodicalIF":2.7,"publicationDate":"2024-05-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11109819/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141082958","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The OptoReg system: a simple and inexpensive solution for regulating water oxygen.","authors":"Rasmus Ern, Fredrik Jutfelt","doi":"10.1093/conphys/coae024","DOIUrl":"10.1093/conphys/coae024","url":null,"abstract":"<p><p>This paper describes an optocoupler-based regulation apparatus for saturation manipulation of oxygen in water (OptoReg). This system enables control of solenoid valves for oxygen and nitrogen gases using a FireSting-O₂ meter, an optocoupler box and an electronic switch box. The hardware components connect to a computer through Universal Serial Bus (USB) cables. The control software is free and has a graphical user interface, making it easy to use. With the OptoReg system, any lab with a computer running Microsoft Windows operating system and a 4-channel FireSting-O₂ meter can easily and cheaply set up four independently controlled systems for regulating water oxygen levels. Here, we describe how to assemble and run the OptoReg system and present a data set demonstrating the high precision and stability of the OptoReg system during static acclimation experiments and dynamic warming trials.</p>","PeriodicalId":54331,"journal":{"name":"Conservation Physiology","volume":"12 1","pages":"coae024"},"PeriodicalIF":2.7,"publicationDate":"2024-05-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11087874/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140913224","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Can blubber steroid hormone measurements reveal reproductive state in narwhals?","authors":"Justine M Hudson, James Simonee, Cortney A Watt","doi":"10.1093/conphys/coae020","DOIUrl":"https://doi.org/10.1093/conphys/coae020","url":null,"abstract":"Hormone measurements from blubber samples have been used to assess reproduction in cetaceans and are a widely applicable technique, as blubber samples are often collected from necropsied individuals and biopsies are readily collected from live, free-swimming cetaceans. Many studies have assessed reproduction in cetaceans based on blubber hormone concentrations but few have validated their findings with individuals of known reproductive state. The objectives of this study were to use a unique dataset of paired female narwhal (Monodon monoceros) reproductive tracts and blubber samples to: (1) determine narwhal reproductive state based on ovarian analysis; (2) evaluate progesterone, estradiol, testosterone and corticosterone concentrations in paired blubber samples to validate the use of blubber hormone measurements as a technique to assess reproductive state in narwhals; and (3) determine narwhal reproductive rates using reproductive tract and hormone analyses. Female narwhals with complete reproductive tracts or known ages (n = 13) were categorized as: pregnant (fetus or placenta present; n = 5), active (at least one corpus luteum present; n = 2), resting (at least one corpus albicans present; n = 3) or immature (absence of corpora lutea and albicantia or age &amp;lt;8; n = 3), and eight individuals were classified as unknown due to incomplete reproductive tracts. Estradiol, testosterone, and corticosterone concentrations were not useful for assessing reproductive state; however, progesterone concentrations were higher in pregnant narwhals (432.66 ± 182.13 ng/g) than active (1.57 ± 0.42 ng/g), resting (1.52 ± 0.87 ng/g) and immature (1.44 ± 0.71 ng/g) individuals, validating the use of blubber progesterone concentrations in determining pregnancy in narwhals. Using a progesterone threshold for pregnancy, determined in this study, we were able to classify three individuals with incomplete reproductive tracts as pregnant and identify a potential impending pregnancy loss. The results from this study suggest that blubber progesterone concentrations are useful for assessing pregnancy and can help inform reproductive rates of narwhal populations.","PeriodicalId":54331,"journal":{"name":"Conservation Physiology","volume":"187 1","pages":""},"PeriodicalIF":2.7,"publicationDate":"2024-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140930387","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}