Wildlife Monographs最新文献

{"title":"Calf Survival of Woodland Caribou in a Multi-Predator Ecosystem","authors":"DAVID D. GUSTINE, KATHERINE L. PARKER, ROBERTA J. LAY, MICHAEL P. GILLINGHAM, DOUGLAS C. HEARD","doi":"10.2193/0084-0173(2006)165[1:CSOWCI]2.0.CO;2","DOIUrl":"https://doi.org/10.2193/0084-0173(2006)165[1:CSOWCI]2.0.CO;2","url":null,"abstract":"<div>\u0000 \u0000 <section>\u0000 \u0000 <h3> ABSTRACT</h3>\u0000 \u0000 <p>The proximate role of predation in limiting caribou (<i>Rangifer tarandus</i>) populations is well documented, but the long-term effects of predation pressure on selection of calving areas and the subsequent impacts to calving success remain unclear. We examined the relationships among calf survival, predation risk, and vegetation characteristics among 3 calving areas and across spatial scales in the Besa-Prophet River drainage of northern British Columbia. Fifty woodland caribou (<i>R. t. caribou</i>) neonates were collared and monitored twice daily for the first month and once weekly during the next month of life in 2 summer field seasons (2002 and 2003). Predation risk was estimated using resource selection functions (RSFs) from Global Positioning System (GPS) locations of 15 grizzly bears (<i>Ursus arctos</i>) and 5 gray wolf (<i>Canis lupus</i>) packs. The Normalized Difference Vegetation Index (NDVI) derived from Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper (ETM) data were used to quantify large-scale characteristics of vegetation (indices of biomass and quality). We incorporated small- and large-scale characteristics (i.e., predation risk, vegetation, and movement of woodland caribou calves) of neonatal calving sites into logistic regression models to predict survival for the calving (25 May–14 Jun) and summer (15 Jun–31 Jul) seasons. Predation risk and vegetation characteristics were highly variable among calving areas and calving sites, and parturient woodland caribou responded to these characteristics at different scales. Minimizing gray wolf risk and selecting against areas of high vegetation biomass were important at large scales; areas with high biomass were likely associated with increased predation risk. Calving in areas high in vegetation quality was important across scales, as parturient woodland caribou took higher levels of predation risk to access areas of high vegetative change. Models using small-scale characteristics of calving sites to predict survival performed better in the calving season than in summer. Large-scale characteristics predicted survival of woodland caribou neonates better in summer than in the calving season, probably in part because of the unexpected role of wolverines (<i>Gulo gulo</i>) as the main predator of woodland caribou calves during calving. Gray wolves were the main cause of mortality during the summer. Movement away from calving sites corresponded to higher calf survival and appeared to be in response to increased access to forage during the peak demands of lactation and/or minimizing gray wolf risk in the summer. High variation in predation risk and vegetation attributes among calving areas and at calving sites within calving areas, with no differences in calf mortality related to that variation, illustrates the importance of behavioral plasticity as a life-history strategy fo","PeriodicalId":235,"journal":{"name":"Wildlife Monographs","volume":"165 1","pages":"1-32"},"PeriodicalIF":4.4,"publicationDate":"2010-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2193/0084-0173(2006)165[1:CSOWCI]2.0.CO;2","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"6207322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nesting Density and Reproductive Success of Piping Plovers in Response to Storm- and Human-Created Habitat Changes","authors":"JONATHAN B. COHEN, LAWRENCE M. HOUGHTON, JAMES D. FRASER","doi":"10.2193/2007-553","DOIUrl":"https://doi.org/10.2193/2007-553","url":null,"abstract":"<div>\u0000 \u0000 <section>\u0000 \u0000 <h3> ABSTRACT</h3>\u0000 \u0000 <p>The threatened population of Atlantic Coast piping plovers (<i>Charadrius melodus</i>) has increased under intensive management of predation and disturbance. However, the relative importance of habitat quality, nest predation, and chick predation in population dynamics and reproductive success of this species are poorly understood. We examined effects of breeding-habitat alterations, predation, and breeding phenology on population size, habitat use, and reproductive output of piping plovers from 1993 to 2004. We studied piping plovers at a newly colonized site (West Hampton Dunes [WHD]) on a New York, USA, barrier island, and an adjacent reference site (REF) with a long-standing population. We monitored population size and reproductive success; determined chick habitat use and behavior; and monitored changes in habitat availability, prey abundance, and predator presence. Resource agencies managed predation by mammal trapping and by fencing nests with predator exclosures in some years. Following storm- and human-related increases in nesting and foraging habitat, the population at WHD grew from 5 pairs in 1993 to 39 pairs in 2000. The WHD population then declined to 18 pairs by 2004 concurrent with habitat losses to human development. In contrast, the population size at REF was not correlated with nesting habitat area. Population growth rate decreased with density at WHD but not at REF, which was likely close to equilibrium when the study began. Neither reproductive output nor any of its components were correlated with population density, and reproductive output was correlated between the sites despite their different population trajectories, suggesting that the population was primarily regulated by adult survival, emigration, or immigration. The latter 2 factors should be especially sensitive to local habitat quality, and the main differences between our sites was that bayside intertidal flats were available adjacent to nesting habitat at WHD but not at REF, and that a village construction project took place at WHD. Clutch size and renest rate decreased over the breeding season. Predator exclosures improved nest daily survival, and mammal trapping improved chick daily survival. Chick foraging rate was highest in bayside intertidal flats and in ocean- and bayside fresh wrack. Chicks used the bay side more than expected from percentage habitat area, and survived better on the bay side before village construction and the initiation of predator trapping, but not after. At both sites, number of chicks fledged per pair was lowest for pairs that nested late and lost a nest late in the season and increased with the annual number of cats (<i>Felis catus</i>) and foxes (<i>Vulpes vulpes</i>) trapped. Restoring nesting habitat adjacent to bayside intertidal flats may increase the carrying capacity (nesting pairs) at piping plover breeding sites. However","PeriodicalId":235,"journal":{"name":"Wildlife Monographs","volume":"173 1","pages":"1-24"},"PeriodicalIF":4.4,"publicationDate":"2010-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2193/2007-553","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"6218769","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Population Dynamics of Spotted Owls in the Sierra Nevada, California","authors":"Jennifer A. Blakesley, Mark E. Seamans, Mary M. Conner, Alan B. Franklin, Gary C. White, R. J. Gutiérrez, James E. Hines, James D. Nichols, Thomas E. Munton, Daniel W. H. Shaw, John J. Keane, George N. Steger, Trent L. Mcdonald","doi":"10.2193/2008-475","DOIUrl":"https://doi.org/10.2193/2008-475","url":null,"abstract":"<p><b>ABSTRACT</b> The California spotted owl (<i>Strix occidentalis occidentalis</i>) is the only spotted owl subspecies not listed as threatened or endangered under the United States Endangered Species Act despite petitions to list it as threatened. We conducted a meta-analysis of population data for 4 populations in the southem Cascades and Sierra Nevada, California, USA, from 1990 to 2005 to assist a listing evaluation by the United States Fish and Wildlife Service. Our study areas (from N to S) were on the Lassen National Forest (LAS), Eldorado National Forest (ELD), Sierra National Forest (SIE), and Sequoia and Kings Canyon National Parks (SKC). These study areas represented a broad spectrum of habitat and management conditions in these mountain ranges.</p><p>We estimated apparent survival probability, reproductive output, and rate of population change for spotted owls on individual study areas and for all study areas combined (meta-analysis) using model selection or model-averaging based on maximum-likelihood estimation. We followed a formal protocol to conduct this analysis that was similar to other spotted owl meta-analyses. Consistency of field and analytical methods among our studies reduced confounding methodological effects when evaluating results. We used 991 marked spotted owls in the analysis of apparent survival. Apparent survival probability was higher for adult than for subadult owls. There was little difference in apparent survival between male and female owls. Model-averaged mean estimates of apparent survival probability of adult owls varied from 0.811 ± 0.021 for females at LAS to 0.890 ± 0.016 for males at SKC. Apparent survival increased over time for owls of all age classes at LAS and SIE, for adults at ELD, and for second-year subadults and adults at SKC. The meta-analysis of apparent survival, which included only adult owls, confirmed an increasing trend in survival over time. Survival rates were higher for owls on SKC than on the other study areas.</p><p>We analyzed data from 1,865 observations of reproductive outcomes for female spotted owls. The proportion of subadult females among all territorial females of known age ranged from 0.00 to 0.25 among study areas and years. The proportion of subadults among female spotted owls was negatively related to reproductive output (no. of young fledged/territorial F owl) for ELD and SIE. Eldorado study area and LAS showed an alternate-year trend in reproductive output, with higher output in even-numbered years. Mean annual reproductive output was 0.988 ± 0.154 for ELD, 0.624 ± 0.140 for LAS, 0.478 ± 0.106 for SIE, and 0.555 ± 0.110 for SKC. Eldorado Study Area exhibited a declining trend and the greatest variation in reproductive output over time, whereas SIE and SKC, which had the lowest reproductive output, had the lowest temporal variation. Meta-analysis confirmed that reproductive output varied among study areas. Reproductive output was highest for adults, followed by secon","PeriodicalId":235,"journal":{"name":"Wildlife Monographs","volume":"174 1","pages":"1-36"},"PeriodicalIF":4.4,"publicationDate":"2010-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2193/2008-475","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"5834220","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Responses of Desert Bighorn Sheep to Removal of Water Sources","authors":"JAMES W. CAIN III, PAUL R. KRAUSMAN, JOHN R. MORGART, BRIAN D. JANSEN, MARTIN P. PEPPER","doi":"10.2193/2007-209","DOIUrl":"https://doi.org/10.2193/2007-209","url":null,"abstract":"<div>\u0000 \u0000 <section>\u0000 \u0000 <h3> ABSTRACT</h3>\u0000 \u0000 <p>In arid regions of the southwestern United States, water is often considered a primary factor limiting distribution and productivity of desert ungulates, including desert bighorn sheep (<i>Ovis canadensis mexicana</i>). Thus, wildlife management agencies and sportsmen's organizations have invested substantial time and resources in the construction and maintenance of water catchments. Although the availability of freestanding water sources is believed to influence many aspects of the ecology of desert bighorn sheep, the efficacy of these water sources has been questioned and has not been examined experimentally. We used a before-after-control-impact study design to determine if removal of water catchments changed diet, characteristics of foraging areas used by female desert bighorn sheep, home-range size, movement rates, distance to catchments, adult mortality, productivity, or juvenile recruitment in 2 mountain ranges on the Cabeza Prieta National Wildlife Refuge, Arizona, USA. During pretreatment (2002–2003), we ensured that water catchments were available to desert bighorn sheep in both mountain ranges; during posttreatment (2004–2005), we drained all water catchments in the treatment range. We measured diet composition, characteristics of foraging areas, 50% and 95% kernel home ranges, movement rates, and distance to water catchments seasonally from 2002 to 2005. We also estimated adult survival, lamb:female, and yearling:female ratios from 2002 to 2005. We predicted that removal of water catchments would result in 1) increased use of foraging areas with more vegetation cover, more thermal cover, and higher succulent abundance; 2) increased consumption of cacti and other succulents; 3) an increase in home-range size, movement rates, and distance to nearest catchment; and 4) a decrease in adult survival, productivity, and juvenile recruitment. Removal of water catchments in the treatment range did not result in predicted changes in diet, foraging area selection, home-range size, movement rates, mortality, productivity, or recruitment. Female desert bighorn sheep did use areas with more thermal cover during the summer after removal of water catchments, but other characteristics of foraging areas used by bighorn sheep and their diet did not change appreciably with removal of water catchments. We did not document changes in home-range area, movement rates, or distance sheep were from water during hotter months; we only documented changes in home-range area, movement rates, and distance to water catchments during winter and autumn. There were 10 desert bighorn sheep mortalities in the treatment range and 8 in the control range; 7 mortalities in each mountain range were during pretreatment. Twelve of the 18 total mortalities occurred during summer. Survival rate was lower during pretreatment than posttreatment in both mountain ranges. We did no","PeriodicalId":235,"journal":{"name":"Wildlife Monographs","volume":"171 1","pages":"1-32"},"PeriodicalIF":4.4,"publicationDate":"2010-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2193/2007-209","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"6207313","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Elk Calf Survival and Mortality Following Wolf Restoration to Yellowstone National Park","authors":"SHANNON M. BARBER-MEYER, L. DAVID MECH, P. J. WHITE","doi":"10.2193/2008-004","DOIUrl":"https://doi.org/10.2193/2008-004","url":null,"abstract":"<p><b>ABSTRACT </b> We conducted a 3-year study (May 2003–Apr 2006) of mortality of northern Yellowstone elk (<i>Cervus elaphus</i>) calves to determine the cause for the recruitment decline (i.e., 33 calves to 13 calves/100 adult F) following the restoration of wolves (<i>Canis lupus</i>). We captured, fit with radiotransmitters, and evaluated blood characteristics and disease antibody seroprevalence in 151 calves ≤6 days old (68M:83F). Concentrations (x̄, SE) of potential condition indicators were as follows: thyroxine (T4; 13.8 μg/dL, 0.43), serum urea nitrogen (SUN; 17.4 mg/dL, 0.57), γ-glutamyltransferase (GGT; 66.4 IU/L, 4.36), gamma globulins (GG; 1.5 g/dL, 0.07), and insulin-like growth factor-1 (IGF-1; 253.6 ng/mL, 9.59). Seroprevalences were as follows: brucellosis (<i>Brucella abortus</i>; 3%), bovine-respiratory syncytial virus (3%), bovine-viral-diarrhea virus type 1 (25%), infectious-bovine rhinotracheitis (58%), and bovine parainfluenza-3 (32%). Serum urea nitrogen, GGT, GG, and IGF-1 varied with year; T4, SUN, and GG varied with age (<i>P</i> ≤ 0.01); and SUN varied by capture area (<i>P</i> = 0.02). Annual survival was 0.22 (SE = 0.035, <i>n</i> = 149) and varied by calving area but not year. Neonates captured in the Stephens Creek/Mammoth area of Yellowstone National Park, USA, had annual survival rates >3× higher (0.54) than those captured in the Lamar Valley area (0.17), likely due to the higher predator density in Lamar Valley. Summer survival (20 weeks after radiotagging) was 0.29 (SE = 0.05, <i>n</i> = 116), and calving area, absolute deviation from median birth date, and GG were important predictors of summer survival. Survival during winter (Nov-Apr) was 0.90 (SE= 0.05, <i>n</i> = 42), and it did not vary by calving area or year. Sixty-nine percent (<i>n</i> = 104) of calves died within the first year of life, 24% (<i>n</i> = 36) survived their first year, and 7% (<i>n</i> = 11) had unknown fates. Grizzly bears (<i>Ursus arctos</i>) and black bears (<i>Ursus americanus</i>) accounted for 58–60% (<i>n</i> = 60–62) of deaths, and wolves accounted for 14–17% (<i>n</i> = 15–18). Summer predation (95% of summer deaths) increased, and winter malnutrition (0% of winter deaths) decreased, compared with a similar study during 1987–1990 (72% and 58%, respectively). Physiological factors (e.g., low levels of GG) may predispose calves to predation. Also, the increase in bear numbers since wolf restoration and spatial components finer than the northern range should be considered when trying to determine the causes of the northern Yellowstone elk decline. This is the first study to document the predation impacts from reintroduced wolves on elk calf mortality in an ecosystem already containing established populations of 4 other major predators (i.e., grizzly and black bears, cougars [<i>Puma concolor</i>], and coyotes [<i>Canis latrans</i>]). The results are relevant to resource managers of the Yellowstone ecosystem in understanding ","PeriodicalId":235,"journal":{"name":"Wildlife Monographs","volume":"169 1","pages":"1-30"},"PeriodicalIF":4.4,"publicationDate":"2010-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2193/2008-004","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"6235253","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluation of Factors Potentially Influencing a Desert Bighorn Sheep Population","authors":"TED McKINNEY, THORRY W. SMITH, JAMES C. DeVOS Jr.","doi":"10.2193/0084-0173(2006)164[1:EOFPIA]2.0.CO;2","DOIUrl":"https://doi.org/10.2193/0084-0173(2006)164[1:EOFPIA]2.0.CO;2","url":null,"abstract":"<div>\u0000 \u0000 <section>\u0000 \u0000 <h3> ABSTRACT</h3>\u0000 \u0000 <p>We studied a desert bighorn sheep (<i>Ovis canadensis</i>) population in the Mazatzal Mountains (primary study area) in central Arizona and population indices on reference areas between 1989 and 2003. We evaluated disease exposure and nutritional status of desert bighorn sheep, vegetation parameters, predator diets, and mountain lion (<i>Puma concolor</i>) harvest and abundance (1999–2003) and mountain lion predation (1995–2003) as factors potentially affecting desert bighorn sheep and population parameters. We measured rainfall monthly, monitored demography and relative abundance of desert bighorn sheep using aerial surveys, captured and placed radio collars on desert bighorn sheep, and collected samples of blood, parasites, and other pathogenic agents from captured animals. We measured mineral content, relative use, and structural composition of vegetation and determined diets of desert bighorn sheep adults and lambs, dietary intakes of nitrogen (FN), 2,6-diaminopimelic acid (FDAPA), neutral detergent fiber, and minerals using fecal analyses. We incorporated mountain lion reductions as an experimental element, monitored harvest, and used track surveys as an index of relative abundance of the predator and monitored radio-collared desert bighorn sheep to determine mortalities and causes of death. We determined diets of bobcats (<i>Lynx rufus</i>), coyotes (<i>Canis latrans</i>), and mountain lions using fecal analyses. Drought conditions occurred during summer (July-September) and winter (November-April) during 4 and 3 years, respectively, between 1999 and 2003. Annual surveys indicated that the Mazatzal Mountains population declined during drought between 1994 and 1997, experienced low growth and lamb production coincident with above-normal rainfall in 1998 and drought in 1999, and exhibited higher growth, production, and productivity during 2000–2003 despite persistent drought conditions during this period. We observed no clinical symptoms of disease in radio-collared desert bighorn sheep, and hematological and other evidence of exposure to disease agents was unremarkable. Population indices on the primary study and reference areas were positively correlated with winter (November-April) rainfall. We found no evidence of forage overutilization on the primary study area. Rainfall on Mazatzal Mountains was associated with differences in primary production, particularly of forbs, forage mineral concentrations, and diets, nutritional status, and demographic attributes of desert bighorn sheep between 1999 and 2003. Higher winter rainfall was associated with higher forb growth, and higher rainfall was associated with higher concentrations of P and Se but lower levels of Fe in browse; higher concentrations of Ca, P, and Zn in forbs; and higher levels of P, Se, and Zn in grasses. Narrower mean Ca:P ratios of browse and forbs were associated with hi","PeriodicalId":235,"journal":{"name":"Wildlife Monographs","volume":"164 1","pages":"1-36"},"PeriodicalIF":4.4,"publicationDate":"2010-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2193/0084-0173(2006)164[1:EOFPIA]2.0.CO;2","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"6235260","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Aspects of the Thermal Ecology of Bobwhites in North Texas","authors":"FRED S. GUTHERY, ALEXANDR R. RYBAK, SAMUEL D. FUHLENDORF, TIM L. HILLER, STEVEN G. SMITH, WILLIAM H. PUCKETT JR., ROBERT A. BAKER","doi":"10.2193/0084-0173(2004)159[1:AOTTEO]2.0.CO;2","DOIUrl":"https://doi.org/10.2193/0084-0173(2004)159[1:AOTTEO]2.0.CO;2","url":null,"abstract":"<p><b>Abstract: </b> We studied the thermal ecology of northern bobwhites (<i>Colinus virginianus</i>) to better understand the role of temperature in the field behavior of these birds. We obtained descriptive data on thermal aspects of the landscape; bobwhite selection for Normalized Difference Vegetation Index (NDVI; vegetation biomass) classes and cover associations relative to their thermal properties; and thermal conditions at nests, mid-day coverts, and roosts. We collected data on a 796-ha area in the Texas Rolling Plains during May 2000-July 2003 using satellite imagery, black-bulb temperature probes, mortality- and temperature-sensing radiotransmitters, and continuous-recording video cameras for nest observations. Linear models of black-bulb temperature (<i>T</i><sub>bb</sub>) as a function of air temperature (<i>T</i><sub>a</sub>) at a base weather station explained 42–70% of the variation in <i>T</i><sub>bb</sub> in 10 NDVI classes during daylight and 78% during night in summer (all NDVI classes; Jul 2001). During February 2002, <i>T</i><sub>a</sub> explained 38–92% of the variation during day and 89% of the variation at night. The linear models provided a means of qualitatively assessing thermal space on the landscape as <i>T</i><sub>a</sub> changed and of predicting <i>T</i><sub>bb</sub> in NDVI classes. At <i>T</i><sub>a</sub> = 42 °C, 100% of the 796-ha landscape under study had predicted <i>T</i><sub>bb</sub> > 39 °C, the approximate threshold leading to hyperthermia in bobwhites. Based on 9,287 radiolocations of 217 bobwhites, bobwhites selected for all NDVI classes in mixed-shrub cover (sand plum, [<i>Prunus angustifolia</i>]; fragrant sumac, [<i>Rhus aromatica</i>]) on an annual and seasonal basis. If <i>T</i><sub>a</sub> was <35 °C, the approximate upper critical temperature, the operative temperature (<i>T</i><sub>e</sub>) experienced by bobwhites exceeded <i>T</i><sub>a</sub> in 699 of 818 simultaneous readings (<i>n</i> = 24 bobwhites with thermal transmitters) and the difference between <i>T</i><sub>e</sub> and <i>T</i><sub>a</sub> increased as air temperature declined. Data from video cameras indicated thermal stress (i.e., gular flutter) in 25 of 26 incubating bobwhites. Gular flutter began at an average <i>T</i><sub>a</sub> of 30.4 ± 0.2 ±C SE (<i>n</i> = 158) and total bouts of gular flutter averaged 87 minutes/bird/day after 16 June. Data from thermal radiotransmitters indicated 91.3 ± 6.1% of incubating adults were in thermal stress at <i>T</i><sub>a</sub> > 35 °C. Temperature of nest contents averaged about 30 °C and incubating bobwhites appeared to protect nest contents more rigorously from hyperthermia than from hypothermia. Mid-day covert selection (NDVI 6, mixed-shrub cover; <i>n</i> = 58) during summer reduced bobwhite exposure to <i>T</i><sub>bb</sub> > 39 °C by an average of 1,600.7 heating-degree minutes in comparison with random points (<i>n</i> = 58) during 1200–1600 hours. The roosting disc ap","PeriodicalId":235,"journal":{"name":"Wildlife Monographs","volume":"159 1","pages":"1-36"},"PeriodicalIF":4.4,"publicationDate":"2010-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2193/0084-0173(2004)159[1:AOTTEO]2.0.CO;2","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"6207310","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pathogens, Nutritional Deficiency, and Climate Influences on a Declining Moose Population","authors":"DENNIS L. MURRAY, ERIC W. COX, WARREN B. BALLARD, HEATHER A. WHITLAW, MARK S. LENARZ, THOMAS W. CUSTER, TERRI BARNETT, TODD K. FULLER","doi":"10.2193/0084-0173(2006)166[1:PNDACI]2.0.CO;2","DOIUrl":"https://doi.org/10.2193/0084-0173(2006)166[1:PNDACI]2.0.CO;2","url":null,"abstract":"Abstract Several potential proximate causes may be implicated in a recent (post-1984) decline in moose (Alces alces andersoni) numbers at their southern range periphery in northwest Minnesota, USA. These causes include deleterious effects of infectious pathogens, some of which are associated with white-tailed deer (Odocoileus virginianus), negative effects of climate change, increased food competition with deer or moose, legal or illegal hunting, and increased predation by gray wolves (Canis lupus) and black bears (Ursus americanus). Long-standing factors that may have contributed to the moose decline include those typically associated with marginal habitat such as nutritional deficiencies. We examined survival and productivity among radiocollared (n = 152) adult female and juvenile moose in northwest Minnesota during 1995–2000, and assessed cause of death and pathology through carcass necropsy of radiocollared and non-radiocollared animals. Aerial moose surveys suggested that hunting was an unlikely source of the numerical decline because the level of harvest was relatively low (i.e., approx. 15% / 2 yr) and the population usually grew in years following a hunt. The majority of moose mortalities (up to 87% of radiocollared moose [n = 76] and up to 65% of non-radiocollared moose [n = 84]) were proximally related to pathology associated with parasites and infectious disease. Liver fluke (Fascioloides magna) infections apparently constituted the greatest single source of mortality and caused significant pathology in the liver, thoracic and peritoneal cavities, pericardial sac, and lungs. Mortality due to meningeal worm (Parelaphostrongylus tenuis) was less prevalent and was manifested through characteristic neurological disease. Several mortalities apparently were associated with unidentified infectious disease, probably acting in close association with malnutrition. Bone-marrow fat was lower for moose dying of natural causes than those dying of anthropogenic factors or accidents, implying that acute malnutrition contributed to moose mortality. Blood profiles from live-captured animals indicated that those dying in the subsequent 18 months were chronically malnourished. Relative to other populations, average annual survival rates for adult females (0.79 [0.74–0.84; 95% CI]) and yearlings (0.64 [0.48–0.86]) were low, whereas those for calves (0.66 [0.53–081]) were high. Pregnancy (48%) and twinning (19%) rates were among the lowest reported for moose, with reproductive senescence among females being apparent as early as 8 years. Pregnancy status was related to indices of acute (i.e., bone-marrow fat) and chronic (i.e., blood condition indices) malnutrition. Opportunistic carcass recovery indicated that there likely were few prime-aged males (>5 yr old) in the population. Analysis of protein content in moose browse and fecal samples indicated that food quality was probably adequate to support moose over winter, but the higher fecal protein among anim","PeriodicalId":235,"journal":{"name":"Wildlife Monographs","volume":"166 1","pages":"1-30"},"PeriodicalIF":4.4,"publicationDate":"2010-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2193/0084-0173(2006)166[1:PNDACI]2.0.CO;2","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"6207312","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"SURVIVAL, MOVEMENTS, AND HARVEST OF EASTERN PRAIRIE POPULATION CANADA GEESE","authors":"SUSAN E. SHEAFFER, DONALD H. RUSCH, DALE D. HUMBURG, JEFFERY S. LAWRENCE, GUY G. ZENNER, MURRAY M. GILLESPIE, F. DALE CASWELL, STEVE WILDS, SCOTT C. YAICH","doi":"10.2193/0084-0173(2004)156[1:SMAHOE]2.0.CO;2","DOIUrl":"https://doi.org/10.2193/0084-0173(2004)156[1:SMAHOE]2.0.CO;2","url":null,"abstract":"<p><b>Abstract: </b> The Eastern Prairie Population (EPP) of Canada geese (<i>Branta canadensis interior</i>) nests in the Hudson Bay lowlands of Manitoba and migrates through south-central Manitoba, western Minnesota, and Iowa, with a wintering terminus primarily in Missouri, Arkansas, and southern Illinois. The southern range of the EPP historically extended through Arkansas and along coastal southwestern Louisiana and Texas. However, during the 1950s and 1960s a progressive northern shift in wintering distribution occurred as numbers of geese wintering in Louisiana and Arkansas declined while numbers wintering in Missouri increased. Continued temporal and geographic shifts in fall and winter distributions were suspected during the 1980s when numbers of wintering Canada geese increased in Minnesota and declined in Missouri. However, concurrent increases in numbers of Mississippi Valley Population (MVP; <i>B. c. interior</i>) and Mississippi Flyway Giant Population (MFGP; <i>B. c. maxima</i>) Canada geese in portions of the winter range shared with EPP geese confounded interpretations of winter population and harvest surveys. During 1984-93, researchers conducted a cooperative banding and observation effort to improve information on survival rates, harvest rates, and winter distributions of EPP Canada geese. Consistent harvest regulations within 3-year periods during 1984-93, combined with extensive observations of marked geese, allowed for an integrative analysis of survival and movements of this population relative to changes in harvest pressure. We used observations, recaptures, and hunter recoveries of marked geese to provide information on survival, harvest, and movements of the EPP that is needed for long-term management of this population.</p><p>Annual survival rates of neck-banded adult geese averaged (x ± SE) 0.707 ± 0.019 during 1984-86, 0.651 ± 0.022 during 1987-89 when harvest seasons were restricted, and 0.595 ± 0.028 during 1990-93 when harvest seasons were liberalized. Annual survival rates for neck-banded adults were lower versus leg-banded adults during 1987-89 and 1990-93 (<i>P</i> ≤ 0.05). Mean survival of neck-banded adults during the harvest seasons in 1987-89 was lower than the mean rate in the harvest seasons of 1984-86, primarily due to a low survival estimate in 1989. Survival averaged 0.918 ± 0.0129 during the 1987 and 1988 harvest seasons but declined to 0.665 ± 0.051 during 1989. Restrictions in harvest correlated with a decrease in direct recovery rates and an increase in survival rates of neck-banded adults during the 1987 and 1988 harvest seasons, but not in 1989. Higher recovery rates in 1989-92 suggested that increased harvest mortality contributed to lower survival of adult geese. However, mortality rates during the 1989-92 harvest seasons increased at a greater proportion than increases in direct recovery rates, suggesting that factors other than harvest could have significantly impacted fall mortality rates of","PeriodicalId":235,"journal":{"name":"Wildlife Monographs","volume":"156 1","pages":"1-54"},"PeriodicalIF":4.4,"publicationDate":"2010-12-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2193/0084-0173(2004)156[1:SMAHOE]2.0.CO;2","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"6235258","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Behavior, energetics and management of refuging waterfowl: a simulation model","authors":"R. Frederick","doi":"10.31274/RTD-180813-5034","DOIUrl":"https://doi.org/10.31274/RTD-180813-5034","url":null,"abstract":"A stochastic simulation model, designed to test the effects of alternative management schemes on refuging waterfowl populations, was constructed from data on fall-migrating lesser snow geese (Chen c. caerulescens) at the DeSoto National Wildlife Refuge, Iowa. Components of the model include goose population level, food density and distribution, food-searching flight characteristics, feeding rates, activity and energy budgets, migration rates, and the effects of weather, hunting pressure, and land management practices on the system. Independent data were collected to test the model's validity. The model validly describes movement from the refuge core to distant feeding areas, and it provides insight into factors affecting emigration. Refuge population level was not sensitive to shifts (?20%) in the input values of 25 selected parameters, but hunting mortality and daily foraging distances were sensitive to several combinations of parameter perturbations. Model outcome was most sensitive to changes in digestive efficiency, mean food density, and the proportion of refuge fields in which food was available. In other model experiments, increased hunting pressure caused significant (P < 0.05) increases in hunting mortality and a reduction in the refuge population. The direct effect of hunting was less important in reducing waterfowl population size than the associated disturbance of feeding geese by hunters, which reduced energy gains and subsequently hastened emigration. Geese in the vicinity of the DeSoto Refuge feed almost exclusively on waste corn. Simulated hunting mortality increased significantly (P < 0.0001) when waste-corn density was moderately reduced because increased goose movement resulted in more shooting opportunities for hunters, but, at extremely low levels of food density, refuge use by waterfowl declined and hunting mortality was reduced. When superabundant food was provided on the refuge, hunting mortality was reduced and waterfowl use of the refuge increased. An artificial reduction in size of the feeding arena, from a radius of 121 km to 8 km, did not affect waterfowl population levels because food supplies were adequate within 8 km of the refuge core. The model can be used to simulate the effects of other management scenarios and is a valuable tool for identifying and meeting management objectives. WILDL. MONOGR. 96, 1-35 Journal Paper J-11908 of the Iowa Agriculture and Home Economics Experiment Station, Ames, Iowa, Project 2427. 2 Present Address: Department of Biological Sciences, Eastern Kentucky University, Richmond, KY 40475. 3 Supported jointly by the U.S. Fish and Wildlife Service, Iowa Conservation Commission, Iowa State University, and Wildlife Management Institute. This content downloaded from 157.55.39.35 on Wed, 31 Aug 2016 04:14:15 UTC All use subject to http://about.jstor.org/terms","PeriodicalId":235,"journal":{"name":"Wildlife Monographs","volume":"148 1","pages":"4-25"},"PeriodicalIF":4.4,"publicationDate":"1983-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"69350799","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}