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1.
Pups on San Nicolas Island were counted by two methods; counts by observers on the ground were compared to counts from aerial photographs taken with a 126-mm-format camera with image motion compensation. No difference was detected between photographic counts and ground counts (P= 0.367) when ground counters had unobstructed views. However, ground counts were significantly lower when areas with obstructed views were included in the analysis (P < 0.001). For areas with unobstructed viewing conditions, no difference was detected between counts by the two methods for rock substrates (P= 0.140), sand substrates (P= 0.468), or mixed rock-and-sand substrates (P= 0.968). No differences were found among three replicate aerial photographic censuses (P= 0.432), but a significant difference was found between two replicate ground censuses (P= 0.037). Total counts obtained from the aerial photographs were more precise (CV = 0.042) than counts obtained on the ground (CV = 0.078). Less variability in counts was found between photographic counters than for ground counters.  相似文献   

2.
Survival in captivity was calculated for 1,707 bottlenose dolphins (BD), 72 killer whales (KW), 73 white whales (WW), 3,090 California sea lions (CSL), and 47 Steller sea lions (SSL) based on data in the Marine Mammal Inventory Report (MMIR) of the NMFS. Mean annual survival rates (ASRs) between 1988 and 1992 were 0.951, 0.937, and 0.954 for BD, KW, and WW, respectively, and 0.952 and 0.969 for CSL and SSL, respectively. These estimates represent significant increases in survival for both BD and CSL over the last 5 yr. Using all of the MMIR data (1940–1992), the ASR of BD calves (< 1 yr of age) was significantly less than the ASR of non-calves (0.666 vs .948, 0.001). Similarly, the ASR of CSL pups (< 1 yr of age) was significantly less than survival of non-pups (0.858 vs .962, 0.001). Survival of captive-born CSL was significantly higher than those born in the wild (0.962 vs .945, 0.003), but the difference was not significantly different for BD (0.948 vs .944, 0.60). For non-calf BD and KW, captive animals survived at a slightly lower rate (BD 0.944 vs .961, = 0.07; KW 0.938 vs .976, 0,001) than animals in the wild (BD: Wells and Scott 1990, KW: Olesiuk 1990). Survival of captive non-pup SSL was slightly higher (0.968 vs .930) than animals in the wild (York 1994, life-table analyses). Survival rates were significantly different among institutions for BD calves and non-calves, CSL pups and non-pups, and SSL non-pups.  相似文献   

3.
Estimates of Steller sea lion ( Eumetopias jubatus ) pup production are valuable for estimating population trend and size. Currently in Alaska, pups are counted by visiting rookeries, driving older animals into the water, then walking through the rookeries and counting the pups, a highly disruptive procedure. At smaller rookeries, with good vantage points, pups are occasionally counted from the periphery of rookeries without disturbing the sea lions. We evaluated counts made from medium-format, color, aerial photographs as an alternative to drive counts and peripheral counts. Neither the peripheral counts nor the aerial photographic counts disturbed animals on the rokeries. There were strong 1:1 linear relationships between photographic counts and drive counts ( r 2= 0.966, P < 0.001) and between photographic counts and peripheral counts ( r 2= 0.999, P < 0.001). Precision was similar for all three methods of counting. We suggest that medium-format, color, aerial photographs is appropriate for routine surveys of Steller sea lion pups in Alaska because it is not disruptive to the hauled-out sea lions and provides comparable estimates with similar precision to drive and peripheral counts. Large areas canbe rapidly surveyed during periods of good weather with a minimum of manpower.  相似文献   

4.
Steller sea lion (Eumetopias jubatus) numbers in the United States declined by about 75% over the past 20+ yr. They are classified, under the U. S. Endangered Species Act, as “threatened” in the eastern portion of their range and as “endangered” in the western portion. We analyzed trends in numbers of pup and non-pup Steller sea lions counted in Southeast Alaska between 1979 and 1997. Sea lion numbers, based on counts of pups on rookeries, increased by an average of 5.9% per year between 1979 and 1997. However, numbers of pups increased at a much slower rate (+ 1.7% per year) between 1989 and 1997. For counts of non-pup Steller sea lions we used models that controlled for the effects of date, time, and tide at the time of the survey to analyze trends. This technique reduced bias and increased precision of the resulting trend estimates. Numbers of sea lions were stable (+0.5%) between 1989 and 1996, based on counts of non-pups. We estimated the Southeast Alaska breeding population of Steller sea lions at about 19,000 animals of all ages in 1997, a level that is probably near the highest in recorded history.  相似文献   

5.
Pup production on Sable Island, Nova Scotia, has been increasing exponentially since the early 1960s and by 1997 Sable Island was the largest gray seal colony worldwide. Using an aerial photographic survey, as in previous years, we estimated pup production in January 2004 to determine if this exponential rate of increase had continued. A total of 33,268 pups was counted on the color positives. When corrected for the proportion pups missed on the imagery (1.106 for the 12th; 1.527 on the 13th), the proportion of pups that died prior to the survey (0.031), and the proportion of pups born before the survey (east colony 0.966, west colony 0.962), estimated total pup production was 41,500 with SE = 4,381. The 2004 estimate indicates that pup production on Sable Island has continued to increase, but suggests that the rate of increase ( r ) may have declined (0.070 compared to previous 0.128). Females from the 1998–2000 cohorts were about 16 times less likely to give birth for the first time at age 4 yr and more than twice as likely at age 6 yr compared to those in the mid-late 1980s. The new estimate of pup production and observed changes in age of primiparity provide the first indication of changes in vital rates of this population. However, additional estimates of pup production and vital rates are needed to confirm this conclusion and to investigate the underlying mechanisms.  相似文献   

6.
A mark-recapture study conducted in 1987–1992 provided weight measurements of juvenile male northern fur seals ( Callorhinus ursinus ) on St. Paul Island, Alaska, at ages ranging from approximately 1.5 mo to 5 yr. Males born in 1987 tended to weigh less at ages 3 and 4 yr than those born in other years. Weights of individuals at ages 2, 3, and 4 yr were significantly correlated with their weights as pups ( P < 0.05). Weights at ages 2 and 3, 3 and 4, and 4 and 5 yr were significantly correlated ( P < 0.001), although weight changes with age were highly variable. Data indicate that larger than average male pups born during 1987–1990 were more likely to survive, but this effect was less evident than among pups born during 1960–1965 when average pup weights were lower.  相似文献   

7.
The number of seals on shore at Tugidak Island (Gulf of Alaska) declined 72%–85% between 1976 and 1988 and increased during the 1990s. We compared pupping phenology and the ratio of pupping-period counts to molting-period counts between declining (1976–1979) and increasing (1994–1998) years, and examined the sex/age structure of seals ashore during the 1990s. In the 1970s the onset and peak of pupping occurred 6–18 d later than in the 1990s. Rate of pup abandonment was higher in 1978 than in the 1990s. Between 1994 and 1995, the maximum and mean number of seals ashore increased >50%, largely due to an increase in non-pups. From 1995 to 1998, the sex/age structure of seals ashore was similar among years. We observed three to four times as many seals during the molting period than during the pupping period in the 1970s, whereas similar numbers were ashore during these periods in the 1990s, perhaps reflecting changes in demography and/or haul-out behavior. Changes in pupping phenology and demography may reflect environmental changes, such as food availability, and when monitored in conjunction with population counts, may help us better interpret changes in the number of seals ashore.  相似文献   

8.
The distribution and abundance of harbor seals ( Phoca vitulina richardii ) in Oregon were monitored from 1977 to 2003 by aerial photographic surveys. Harbor seals on shore were counted each year during the reproductive period. Mean annual counts of non-pups (adults and subadults) were used as an index of population size and the trend in the counts was modeled using exponential (density-independent) and generalized logistic (density-dependent) growth models. Models were fit using maximum likelihood and evaluated using Akaike's Information Criterion. The population dynamics of harbor seals in Oregon were best described by the generalized logistic model. The population grew following protection under the Marine Mammal Protection Act of 1972 until stabilizing in the early 1990s. The estimated absolute abundance of harbor seals (all age classes) during the 2002 reproductive period was 10,087 individuals (95% confidence interval was 8,445–12,046 individuals). The current predicted population size for harbor seals in Oregon is above its estimated maximum net productivity level and hence within its optimum sustainable population range. We speculate that recent increases in ocean productivity in the eastern Pacific Ocean may lead to an increase in carrying capacity and renewed growth in Oregon's harbor seal population.  相似文献   

9.
Methods commonly used to estimate the number of nests and size of the breeding population at colonies of Least Terns (Sternula antillarum) and other waterbirds include walk‐through counts of nests (ground‐nest counts) and counts of incubating adults from the colony perimeter (incubating‐adult counts). The bias and variance of different methods and the comparability of repeated surveys versus once‐annual censuses are poorly understood. Our objectives were to assess (1) the potential bias and variation of the more rapid incubating‐adult counts compared to the time‐intensive, and presumably more accurate, ground‐nest counts, and (2) how accurately a once‐annual census captured peak nesting abundance. We studied nine Least Tern colonies at Cape Lookout National Seashore (CALO), North Carolina, from April to August 2010–2012. We analyzed observer and survey method agreement with concordance correlation coefficients (ρc). We deployed time‐lapse cameras at 156 nests and used repeated‐measures logistic regression to determine if the proportion of time spent incubating varied with colony, time of day, or time of season. We found substantial agreement in abundance estimates of Least Tern nests and incubating adults between observers and survey methods, and among different times of day and seasons (all comparisons ρc > 0.97). Least Terns incubated eggs 94% of the time on average during daylight hours, irrespective of colony, nesting stage, or month. Although the nesting peak at CALO occurred during the recommended census period for Least Terns, abundance estimates for surveys conducted at different times during that period varied by as much as 39%. We recommend conducting incubating‐adult counts to estimate nest and breeding population abundance of Least Terns or other waterbirds when vegetation or dunes do not obstruct views of nesting colonies. In addition, given the variation in abundance estimates for surveys conducted at different times during the recommended survey period, incubating‐adult counts should be performed at least twice during the census period, with the maximum count reported as peak nest abundance.  相似文献   

10.
Ten strains of lentil rhizobia (Rhizobium leguminosarum ) were evaluated for drought tolerance by exposing them to soil moisture potentials of −0·03, −1·0 and −1·5 MPa. Water availability, rhizobial strain and time of exposure to drought had a significant ( P ≤ 0·001) effect on the number of surviving rhizobia g−1 of soil. Highest cell counts were observed at −0·03 MPa, followed by soil maintained at −1·0 and −1·5 MPa. Five strains originating from saline areas showed significantly ( P ≤ 0·05) better survival under low water potential after 35 days. Two strains exhibited greatest survival under low water potential and produced viable cell counts of more than 107 rhizobia g−1 of soil. These strains could probably be used successfully as inoculants for lentil production in arid and semi-arid environments.  相似文献   

11.
Glacier Bay National Park had one of the largest breeding aggregations of harbor seals in Alaska, and it is functionally the only marine reserve for harbor seals in Alaska; yet, numbers of seals in the Bay are declining rapidly. Understanding why seals in Glacier Bay are declining may clarify their minimal habitat needs. We estimated population trends using models that controlled for environmental and observer‐related factors. In 1992, 6,200 seals were counted on icebergs in a tidewater glacial fjord and at terrestrial sites; by 2002 only 2,550 seals were counted at these same haul‐outs. Numbers of non‐pups in the glacial fjord declined by 6.6%/yr (?39%/8 yr) in June and by 9.6%/yr (?63%/11 yr) in August and at all other haul‐outs by 14.5%/yr (?75%/10 yr) during August. In the glacial fjord the number of pups remained steady from 1994 to 1999 and made up an increasing proportion of seals counted (5.4%/yr), and the proportion of pups peaked at 34%–36%. The rapid declines do not appear to be due to changes in seal behavior or redistribution. The declines reinforce genetic evidence that harbor seals in Glacier Bay are demographically isolated from other populations and indicate that current management stocks need to be redefined. Changes in Glacier Bay's ecosystem and population demographic data from the glacial fjord suggest that interspecific competition and predation are likely factors in the declines.  相似文献   

12.
We estimated the number of live Australian fur seal pups using capture-markresights, direct ground counts, or aerial photography at all breeding sites following the pupping season of November-December 2002. Pups were recorded at 17 locations; nine previously known colony sites, one newly recognized colony and seven haul-out sites where pups are occasionally born. In order of size, the colonies were Lady Julia Percy Island (5,899 pups), Seal Rocks (4,882), The Skerries (2,486), Judgment Rocks (2,427), Kanowna Island (2,301), Moriarty Rocks (1,007), Reid Rocks (384), West Moncoeur Island (257), and Tenth Island (124). The newly recognized site was Rag Island, in the Cliffy Group, where we recorded 30 pups. We also recorded pups at the following haul-out sites: Cape Bridge-water (7 pups), Bull Rock (7), Wright Rock (5), Twin Islet (1), The Friars (1), He des Phoques (1), and Montague Island (1). In total, we estimate there were 19,819 (SE = 163) live pups at the time of the counts. We discuss trends in pup numbers and derive current population estimates for the Australian fur seal.  相似文献   

13.
We studied the ontogeny of hemoglobin concentration, hematocrit and erythrocyte counts in the Galapagos fur seal ( Arctocephalus galapagoensis , Heller 1904). Two hundred and fifty-three animals were sampled between the ages of 22 d and > 8 yr, of which 46 were adult females. Body mass increased steadily with age from 6.1 ± 1.2 kg in 1-mo-old pups ( n = 27) to 28.5 ± 3.3 kg in adult females. Even adult females increased in mass with age. Hemoglobin (Hb), hematocrit (Hct), and red blood cell (RBC) values all increased in a logarithmic fashion with age up to 2 yr. Blood values for pups were Hct: 35.5 ± 4.1%; Hb: 12.9 ± 1.3 g/dl; RBC: 4.1 ± 0.3·106/μl. Half-year-old fur seals (Hct: 42.1 ± 3.2%; Hb: 15.7 ± 1.3 g/dl; RBC: 4.9 ± 0.5·106/μl; n = 50) were the oldest age group to show significantly lower blood values than adult females ( P < 0.001 for all three parameters). Yearling blood values (Hct: 47.2 ± 3.6%; Hb: 17.3 ± 1.6 g/dl; RBC: 5.6 ± 0.4·106/μl; n = 56) did not differ significantly from those of adult females ( P < 0.32; P < 0.26; P < 0.23, respectively). Blood values of adult females were lower than those of 2-yr-olds (Hct: 49.6 ± 2.4%; Hb: 18.5 ± 1.2 g/dl; RBC: 5.7 ± 0.3·106/μl; n = 31). These differences were significant only for RBCs ( P < 0.003). Up to the age of 1 yr, age was the best predictor for blood values, thereafter mass tended to be a better predictor. Female juveniles between the ages of 150 and 600 d had higher blood values than same-age males. The relationship of blood value development to diving activity is briefly described and the results are compared to values of other marine mammals. Ontogeny is discussed in relation to the development of these blood values in terrestrial mammals.  相似文献   

14.
Recent pup population estimates of sympatric Subantarctic (Arctocephalus tropicalis) and Antarctic fur seals (A. gazella) at Marion Island are presented. Published pup population estimates of A. tropicalis (1995 and 2004) with an unpublished total island count in 2013, and annual counts on subsets of rookeries (2007–2015) were analyzed using a hierarchical Bayesian model. The pup population declined by 46% (95% credible interval CI: 43%–48%) between 2004 (mean = 15,260, CI: 14,447–16,169 pups) and 2013 (mean = 8,312, CI: 7,983–8,697), mirrored by a 58%–60% decline at rookeries counted annually (2007–2015). Population decline was highest at high‐density west and north coast rookeries, despite negligible change in female attendance patterns, pup mortality or median pupping date over the previous 25 yr. A better understanding of foraging behavior and its effects on reproductive success and survival in this A. tropicalis population is needed before we can attribute population decline to any external factors. In contrast, total island counts of A. gazella pups in 2007, 2010, and 2013, suggest that this population is still increasing although the annual intrinsic rate of population growth decreased from 17.0% (1995–2004, 744 pups) to 4.0% (2010–2013, 1,553 pups). The slowed growth of A. gazella is likely the result of saturation at the main rookery.  相似文献   

15.
Standard hematologic and serum chemistry parameters were determined from 28 harp seals (Phoca groenlandica) and 20 hooded seals (Cystophora cristata) sampled from 6 March 2001 to 13 March 2001 during the breeding season. Whole blood was collected immediately postmortem from harp seal mother-pup pairs and from six hooded seal pups, and from live-captured adult hooded seals and three hooded seal pups; blood was analyzed within 24 hr at a local human hospital. A certified veterinary laboratory validated subsamples of whole blood and analyzed all serum chemistry parameters. Significant interlaboratory differences in mean values of packed cell volume (PCV) and mean cell volume (MCV) were found. Significant differences were found between samples from the five seal groups (adult male hooded seals, lactating female hooded seals, unweaned hooded seal pups; lactating female harp seals, and unweaned harp seal pups) for hematology and most serum chemistry parameters. In general, age-class influenced mean values of PCV, hemoglobin (HB), red blood cell (RBC) counts, MCV, mean cell hemoglobin (MCH), mean cell hemoglobin concentration (MCHC), and nucleated red blood cell (NRBC) counts per 100 leucocytes, but most age-related variations were species specific. Harp seal pups had significantly lower mean values of HB, PCV, MCH, and MCHC than did other seal groups, and significantly lower mean RBC counts than did hooded seal pups. Mean NRBC counts per 100 leukocytes were more than three times higher in harp seal pups than in hooded seal pups, but this difference was not statistically significant. Mean MCV were significantly lower in harp and hooded seal pups compared to those of adult harp and hooded seals. Differences in hemograms between pup species were likely because of the precocious development of hooded seal pups, which are weaned within 4 days, compared to 12 days for harp seal pups. Among adult seal groups, male hooded seals had significantly higher mean values of PCV and HB than did female harp and hooded seals, and significantly higher mean RBC counts than did adult female hooded seals. Among adult females, mean values of MCH and MCHC were statistically higher in hooded seals than in harp seals. Adult female harp and hooded seals did not differ significantly in other RBC parameters and mean leukocyte counts. Mean values of glucose, blood urea nitrogen, total bilirubin, alanine aminotransferase (ALT), alkaline phosphatase (ALP), total protein, and albumin showed species-specific variations between adults and pups. Except for ALP, few significant differences in mean enzyme activities of aspartate aminotransferase (AST), ALT, creatine kinase and gamma-glutamyltransferase were found between seal groups. Mean concentrations of electrolytes (calcium, phosphorus, sodium, potassium, chloride, magnesium, and total carbon dioxide) varied with age class, but variations in potassium and magnesium were species specific. Harp seal pups had significantly higher mean phosphorus and potassium levels compared to other seal groups.  相似文献   

16.
A breeding population of black-browed albatrosses has been known to exist at the Ildefonso Archipelago, Chile, for >90 years but the population has never been censused using scientifically defendable methods. To estimate population size, and examine the accuracy and practicality of various census methods, the population was censused in the 2002/2003 breeding season using (a) ground-truthed aerial photography, (b) yacht-based photography, (c) ground counts, (d) quadrat sampling and (e) point-distance sampling. Compared to ground-truthed aerial photography (judged the most accurate) yacht-based photography underestimated population size by 55%, ground counts by 13%, quadrat sampling by 11% and point-distance sampling by 9%. Ground-truthed air photography revealed that in the 2002/2003 breeding season 47,000 pairs of black-browed albatrosses bred at the Ildefonso Archipelago. A repeat aerial census in 2006 suggested the size of the breeding population had not changed in the 4 years between the two censuses. After the Falkland Islands/Islas Malvinas, South Georgia and Diego Ramirez, the Ildefonso Archipelago holds the fourth largest population of black-browed albatrosses in the world.  相似文献   

17.
Abstract: Aerial surveys are often used to quantify sizes of waterbird colonies; however, these surveys would benefit from a better understanding of associated biases. We compared estimates of breeding pairs of waterbirds, in colonies across southern Louisiana, USA, made from the ground, fixed-wing aircraft, and a helicopter. We used a marked-subsample method for ground-counting colonies to obtain estimates of error and visibility bias. We made comparisons over 2 sampling periods: 1) surveys conducted on the same colonies using all 3 methods during 3–11 May 2005 and 2) an expanded fixed-wing and ground-survey comparison conducted over 4 periods (May and Jun, 2004–2005). Estimates from fixed-wing aircraft were approximately 65% higher than those from ground counts for overall estimated number of breeding pairs and for both dark and white-plumaged species. The coefficient of determination between estimates based on ground and fixed-wing aircraft was ≤0.40 for most species, and based on the assumption that estimates from the ground were closer to the true count, fixed-wing aerial surveys appeared to overestimate numbers of nesting birds of some species; this bias often increased with the size of the colony. Unlike estimates from fixed-wing aircraft, numbers of nesting pairs made from ground and helicopter surveys were very similar for all species we observed. Ground counts by one observer resulted in underestimated number of breeding pairs by 20% on average. The marked-subsample method provided an estimate of the number of missed nests as well as an estimate of precision. These estimates represent a major advantage of marked-subsample ground counts over aerial methods; however, ground counts are difficult in large or remote colonies. Helicopter surveys and ground counts provide less biased, more precise estimates of breeding pairs than do surveys made from fixed-wing aircraft. We recommend managers employ ground counts using double observers for surveying waterbird colonies when feasible. Fixed-wing aerial surveys may be suitable to determine colony activity and composition of common waterbird species. The most appropriate combination of survey approaches will be based on the need for precise and unbiased estimates, balanced with financial and logistical constraints. (JOURNAL OF WILDLIFE MANAGEMENT 72(3):697–706; 2008)  相似文献   

18.
目的:探讨早期宫颈癌患者围手术期外周血淋巴细胞数与其预后之间的关系。方法:回顾性分析2006年1月至2012年12年就诊于解放军总医院,根据2009年最新宫颈癌FIGO指南诊断为Ⅰb~ⅡA期宫颈癌进行阴式宫颈癌根治术患者的临床病历资料。分析患者的围手术期淋巴细胞数和其无瘤生存期、总生存期间的关系。结果:共143例阴式早期宫颈癌根治术患者纳入研究,随访时间为6~87个月,中位随访时间为53个月。术后,宫颈癌患者外周血淋巴细胞数显著下降。术前外周血淋巴细胞数较高的患者无瘤生存期及总生存期均较外周血淋巴细胞数低于平均水平的患者显著延长(P0.05);术后第三天淋巴细胞数恢复或高于术前水平的患者无瘤生存期较术后第三天淋巴细胞数低于术前水平的患者显著延长(P0.05),但总生存期无明显差异(P0.05)。COX回归分析显示术前淋巴细胞数高于平均水平及术后第三天淋巴细胞数高于或等于术前水平的宫颈癌患者的预后相对较好。结论:术前淋巴细胞数和术后第三天淋巴细胞数的变化均可作为评估宫颈癌术后患者预后的重要参考指标。  相似文献   

19.
The aim of this study was to extend 40 yr of prior demographic work on northern elephant seals (Mirounga angustirostris) at Año Nuevo, California, by including the oldest animals. We used a Bayesian mark‐recapture analysis to estimate lifelong survival and lifespan of a cohort of 372 weaned pups branded in 1985–1987 and resighted until 2008. Annual survival probability of females averaged 86.3%/yr at ages 5–16, then declined until age 21, the age of the oldest female. Male survival was lower, averaging 67.7%/yr from age 1 to age 15, the age of the oldest male. Northern elephant seal females in the expanding population at Año Nuevo live longer than southern elephant seal females (M. leonina) at colonies whose populations are declining. This comparison suggests that high survival of females is a key factor in population growth.  相似文献   

20.
Harbor seals, Phoca vitulina, use diverse haul‐out substrates including ice calved by tidewater glaciers. Numbers of seals at glacial and terrestrial haul‐outs on the southeastern Kenai Peninsula, Alaska, were assessed using aerial, vessel, and video surveys. Mean annual abundance at glacial and terrestrial haul‐outs differed temporally. From 2004 to 2011, numbers of seals counted during the molt increased 5.4%/yr at glacial haul‐outs and 9%/yr at terrestrial haul‐outs while numbers of pups increased 5.0%/yr at glacial sites and 1.5%/yr at terrestrial sites. Numbers of seals without pups counted during pupping increased 7.96%/yr at glacial sites and 5.1%/yr at terrestrial sites. Results indicate that pupping and molting locations are not equivalent and population monitoring during the molt does not necessarily reflect habitat association of pupping seals. Ratios of pups to total seals counted during pupping and the subsequent molt were used to contrast habitat use. Low proportions of pups at terrestrial haul‐outs, relative to most glacial haul‐outs, indicate an overall preference for pupping in glacial haul‐outs. High proportions of pups at most glacial sites (during pupping and molting) suggest reduced use of tidewater glacier habitats by nonbreeders and molting seals. Results suggest more seals associate with glacial haul‐outs than currently estimated.  相似文献   

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