Relating annual increments of the endangered Blanding's turtle plastron growth to climate

This research is the first published study to report a relationship between climate variables and plastron growth increments of turtles, in this case the endangered Nova Scotia Blanding's turtle (Emydoidea blandingii). We used techniques and software common to the discipline of dendrochronology to successfully cross‐date our growth increment data series, to detrend and average our series of 80 immature Blanding's turtles into one common chronology, and to seek correlations between the chronology and environmental temperature and precipitation variables. Our cross‐dated chronology had a series intercorrelation of 0.441 (above 99% confidence interval), an average mean sensitivity of 0.293, and an average unfiltered autocorrelation of 0.377. Our master chronology represented increments from 1975 to 2007 (33 years), with index values ranging from a low of 0.688 in 2006 to a high of 1.303 in 1977. Univariate climate response function analysis on mean monthly air temperature and precipitation values revealed a positive correlation with the previous year's May temperature and current year's August temperature; a negative correlation with the previous year's October temperature; and no significant correlation with precipitation. These techniques for determining growth increment response to environmental variables should be applicable to other turtle species and merit further exploration.     

Effect of neck collars on the body condition of migrating Greater Snow Geese

Markers are widely used to study behavior, migration, and the life history traits of birds such as survival, dispersal, and reproductive success. The presence of neck collars has been shown to impact the breeding propensity of adult female Greater Snow Geese (Chen caerulescens atlantica), but not their survival rates. We evaluated the hypothesis that the reduction in breeding propensity in neck‐collared birds was due to a reduction in the body condition of these long‐distance migrants that rely on a partial capital breeding strategy. Our study was conducted during 4 consecutive years along the St. Lawrence estuary in Quebec, Canada, a major spring staging area for these geese. We captured and marked 2552 geese with collars and 34 were recaptured in subsequent years at the same site. After controlling for confounding variables such as year and date of capture, we found that the presence of a neck collar reduced body condition of females during spring staging. Female Greater Snow Geese lost an average of 105.5 ± 39.1 (SE) g (4% of body mass) after carrying a collar for 1 yr and an average of 81.9 ± 43.6 g compared to original mass when recaptured 2 or 3 yr later. Our results suggest that the previously reported reduction in breeding propensity of neck‐collared geese may be due to a reduction in body condition during spring staging. Neck collars could negatively affect the body condition of female Greater Snow Geese by increasing their energy expenditure (due to increased drag during flight or to chronic stress) or reducing their foraging efficiency.     

Genetic effects of landscape,habitat preference and demography on three co‐occurring turtle species

Expanding the scope of landscape genetics beyond the level of single species can help to reveal how species traits influence responses to environmental change. Multispecies studies are particularly valuable in highly threatened taxa, such as turtles, in which the impacts of anthropogenic change are strongly influenced by interspecific differences in life history strategies, habitat preferences and mobility. We sampled approximately 1500 individuals of three co‐occurring turtle species across a gradient of habitat change (including varying loss of wetlands and agricultural conversion of upland habitats) in the Midwestern USA. We used genetic clustering and multiple regression methods to identify associations between genetic structure and permanent landscape features, past landscape composition and landscape change in each species. Two aquatic generalists (the painted turtle, Chrysemys picta, and the snapping turtle Chelydra serpentina) both exhibited population genetic structure consistent with isolation by distance, modulated by aquatic landscape features. Genetic divergence for the more terrestrial Blanding's turtle (Emydoidea blandingii), on the other hand, was not strongly associated with geographic distance or aquatic features, and Bayesian clustering analysis indicated that many Emydoidea populations were genetically isolated. Despite long generation times, all three species exhibited associations between genetic structure and postsettlement habitat change, indicating that long generation times may not be sufficient to delay genetic drift resulting from recent habitat fragmentation. The concordances in genetic structure observed between aquatic species, as well as isolation in the endangered, long‐lived Emydoidea, reinforce the need to consider both landscape composition and demographic factors in assessing differential responses to habitat change in co‐occurring species.     

维生素E对中华鳖幼鳖生长、肝脏维生素E以及血清皮质醇含量的影响

为探讨维生素E(VE)对中华鳖(Pelodiscus sinensis)幼鳖的生长、肝脏VE和血清皮质醇的影响，通过特定生长率、高压液相色谱法和放免法，我们测定了中华鳖幼鳖的生长、肝脏VE和血清皮质醇含量。发现VE添加量为1000和5000mg／kg的两组，能明显降低中华鳖幼鳖的生长。维生素E添加量为500、1000和5000mg／kg的三组，肝脏维生素E含量明显高于对照组，VE添加量在0—1000mg／kg的范围时，肝脏VE的含量随着饲料中VE含量的增加呈指数式增加，并且在VE添加量为5000kg／kg的一组基本达到饱和。维生素E添加量为0和50mg／kg的2组，其血清皮质醇的平均值明显高于维生素E添加量为250、500、1000和5000mg／kg的4组的平均值。上述结果表明：高剂量的VE降低了中华鳖幼鳖的生长和血清皮质醇的含量；在一定剂量范围内，肝脏VE随着饲料中VE含量的增加而升高。     

Influence of somatic cell count, body condition and lameness on follicular growth and ovulation in dairy cows

The objective of this study was to investigate the effect of somatic cell count (SCC), body condition score (BCS) or lameness score on ovarian follicular growth and ovulation in dairy cows. Seventy four animals 30-80 days post-partum were monitored for all three conditions before synchronization of ovarian follicular phases by administration of gonadotrophin releasing hormone (GnRH) followed seven days later with prostaglandin F2alpha (PG). Ultrasonography of both ovaries twice daily throughout the follicular phase revealed that fewer animals with combined high SCC and lameness (4/9) ovulated compared to healthy animals (19/21; P = 0.006) or animals with only high SCC (11/11; P = 0.004) or only lameness (21/27; P = 0.06). Overall, regardless of the presence of other concurrent conditions, fewer lame cows ovulated than Non Lame animals (30/42 and 30/32; P = 0.015). Mean follicular growth and maximum follicular diameter were unaffected by any of the three conditions. However, dominant follicle growth and maximum diameter were greater in the 60 animals that ovulated compared to the 14 that did not; 1.83 ± 0.16 versus 0.96 ± 0.26 mm/day (P = 0.014) and 19.4 ± 0.4 versus 16.4 ± 1.2 mm (P = 0.003), respectively. In conclusion, lameness reduced the proportion of cows that ovulated and the synergistic effect of high SCC and lameness reduced that proportion further. However, follicular growth and maximum follicular diameter were unaffected by high SCC, low BCS or lameness.     

A genetic survey of heavily exploited, endangered turtles: caveats on the conservation value of trade animals

Asian turtles face an extinction crisis, and so it is imperative that systematists accurately determine species diversity in order to guide conservation strategies effectively. We surveyed mitochondrial and nuclear DNA (mtDNA and nuDNA) variation of the heavily exploited Mauremys mutica complex, a clade of Asian turtles that contains the endangered M. mutica from Japan, Taiwan, China and Vietnam, and the critically endangered Mauremys annamensis from central Vietnam. We discovered extensive mtDNA and nuDNA variation among samples that did not correspond to the currently recognized taxonomy. Both nuDNA and mtDNA data suggest that M. mutica is paraphyletic with respect to M. annamensis . Surprisingly, M. annamensis exhibits a previously unknown mtDNA structure in the form of two clades that are paraphyletic to M. mutica . These data reveal that the currently recognized taxonomy of the mutica complex does not reflect the genetic diversity of our samples. Unfortunately, many conservation-oriented captive-breeding efforts for turtles are also based on trade samples such as the ones studied here. These efforts include plans to breed trade-rescued individuals and release their progeny into the wild. Because our genetic survey reveals that the taxonomic identity of these samples does not reflect genetic diversity, we raise serious questions about the efficacy of these programs. In order to address conservation issues and provide more accurate estimates of evolutionary lineages within Mauremys , we recommend continued surveys for wild populations of the mutica complex to provide new genetic material and additional distributional data, attempts to extract DNA from historic museum specimens and a shift in conservation focus to in situ preservation of wild populations and associated habitat.     

Age and growth of round goby Neogobius melanostomus associated with depth and habitat in the western basin of Lake Erie

Round goby Neogobius melanostomus were examined from the Bass Islands area in the western basin of Lake Erie, U.S.A., to determine age and growth correlations. A total of 188 specimens were collected and examined during summer 2011 with 90 aged using scale analysis. Fish were grouped by sex, depth of habitat and habitat type (anthropogenically modified shallows, natural shallows and open lake deep water). Fish ranged from 17 to 117 mm total length (L_T) and 0+ to 3+ years. Males dominated the population (1·94:1) and backcalculated age showed that both sexes grew exponentially, with male growth rate increasing faster than female. Males were significantly larger than females in L_T and mass (both P < 0·001). The relative mass index (W_r) was low for the sampled population (mean ± s.d . = 32·00 ± 26·87 g), implying that the health of the Bass Island area population is very poor when compared with the species throughout its range. This could be due to a lack of food resources related to population size or that the fish is not optimally utilizing the available food resources. In contradiction to these findings, regression slope coefficient (b), calculated using Fulton's condition factor (K) (mean ± s.d . =1·50 ± 0·20), was very low for each habitat, implying a healthy population throughout. This seemingly opposite effect may be due to more individuals per unit area in shallow waters, which would cause increased competition for resources. Poor condition may indicate that the Lake Erie population has reached saturation or may reflect indirect fitness costs associated with increasing anoxic or hypoxic hypolimnion conditions.     

Population level differences in adult body mass emerge in infancy and early childhood: Evidence from a global sample of low and lower‐income countries

Many studies have linked measures of adult body shape and mass in ancient and contemporary populations to ecogeographical variables such as temperature and latitude. These results tend to support Bergmann's rule, which posits that bodies will be relatively less slender for their height in colder climates and more slender in warmer climates. Less well explored is the ontogeny of these population‐level differences. Here we use data on infants and children from 46 low and lower income countries to test whether children's weight for height is associated with measures of temperature and latitude. We also test the hypothesis that children living in areas with greater pathogen prevalence will be lighter for their height because of life history trade‐offs between investment in immune function and growth. Finally, we test whether population specific adult body mass predicts infant and child body mass, and whether this is independent of ecogeographical variables. Our results show that maximum monthly temperature explains 17% of children's weight for height while adult population‐level body mass explains ～44% (Table 5 ). The measures of pathogen prevalence explain little of the variation in children's body shape (8%; P > 0.05). Our results suggest that population differences are consistent with Bergmann's rule but parental body shape explains more variance. Moreover, these population‐level differences arise early in development, suggesting that any possible environmental influences occur in utero and/or result from epigenetic or population genetic differences. Am J Phys Anthropol 154:232–238, 2014. © 2014 Wiley Periodicals, Inc.     

The effects of feeding history and environment on condition,body composition and growth of bluegills Lepomis macrochirus

Initial relative mass (W_R, low v. high) and energetic trajectory in time (starved v. fed) were experimentally manipulated in bluegill Lepomis macrochirus. Fed fish starting at low W_R grew more and gained more W_R than fed fish starting at high W_R. Similarly, starved fish starting at high W_R lost more mass and W_R than did starved fish starting at low W_R. Temporal changes in other variables did not consistently match that of W_R, but, by the end of the experiment, proximate composition showed a high correlation to W_R. Regression slopes of W_R on proximate composition increased with time in the laboratory. Differences between wild and laboratory fish appeared to result from relaxation of environmental stress. When excess resources are available such that L. macrochirus grow, condition indices will increase, but individual response will depend on initial values and thus past environmental experience.     

城市湖泊湿地温湿效应——以武汉市为例

选择武汉城市三环内主城区14块湖泊湿地为研究对象,采用小尺度定量测定的方法,研究城市湖泊湿地与温湿效应间的关系。结果表明:(1)城市湿地温度值与面积指数、距离指数呈显著负相关,与景观形状指数呈显著正相关(P0.05);湿度值与面积指数、距离指数、环境类型指数呈显著正相关,与景观形状指数呈显著负相关(P0.05)。其中面积指数的贡献值最大。(2)14块湖泊湿地的降温增湿效应排序为湖泊11—14湖泊6—10湖泊1—5。当湖泊湿地面积为9.2—12.2 hm2时,其降温增湿效应明显;当湖泊湿地面积为308.4hm2左右时,降温效应显著且趋于稳定,湖泊湿地面积为67.6hm2左右时,增湿效应显著且趋于稳定(P0.05)。当湖泊湿地面积达到临界值之后,多斑块离散型(Dispersive)湖泊湿地布局对整个城市环境的降温增湿效应更为显著。     

Effects of angling on post‐release mortality,gonadal development and somatic condition of Australian bass Macquaria novemaculeata

This study assessed the protracted effects of two angling treatments (mild and harsh) on the post‐release mortality, gonadal development and somatic condition of Australian bass Macquaria novemaculeata in a pond‐based experiment. Angled fish were destructively sampled (along with controls) three times: immediately before, and 1 or 4 weeks after release into cages. Compared with the other groups, harshly angled fish had similar, low immediate and short‐term mortalities (≤5%), but significant delayed mortality (25%) and fed only minimally. None of these fish ejected ingested hooks. Forty‐six per cent of captive fish (across all groups) and 20% of wild fish had non‐ripening gonads (stage I) prior to, or during, the experiment. In females with ripening ovaries (stages II or III), neither angling treatment significantly reduced standardized gonadal mass. The mean per cent of atretic oocytes increased among females in all groups, but was significantly greater in those that were harshly angled. The results demonstrated that the gonadal development of M. novemaculeata could be suppressed or impaired (by angling, handling and confinement), and that further research is warranted. In particular, the timing and severity of angling in relation to the stage of gonadal development could have important implications for the introduction of temporal restrictions to angling.     

Diet and body condition of cave‐dwelling dwarf crocodiles (Osteolaemus tetraspis,Cope 1861) in Gabon

We present the first ever observations of dwarf crocodiles (Osteolaemus tetraspis) selectively utilizing a cave ecosystem. We analysed crocodile diet to preliminarily assess the degree of ecological isolation of cave‐dwelling crocodiles from their forest‐dwelling conspecifics despite their physical proximity. We additionally conducted the first study of body condition of dwarf crocodiles and compared cave‐dwelling individuals to surface‐dwelling individuals from a variety of alternative habitats and sites as a means to better understand the implications of a semihypogean life on this species. Crocodiles captured in the caves appeared to forage exclusively in the caves and ate mostly cave crickets and bats, whereas crocodiles captured in the surrounding forest habitat consumed primarily freshwater crustaceans and insects and were not found to consume cave‐dwelling prey. Juvenile cave crocodiles had significantly higher body condition compared to juvenile forest crocodiles, which did not vary amongst forest locations. The difference in body condition between adult cave and forest crocodiles was not statistically significant despite also being higher; we suspect this is an artefact of the low sample size rather than a real nondifference. Forest adult crocodiles generally had significantly higher body condition than juveniles, but did not vary by site or habitat. This lack of variation suggests that habitat type is not the most important factor influencing dwarf crocodile body condition. Our results provide a unique insight into facultative cave use by a principally surface‐dwelling species and reinforce the necessity for further research into this unique system to better understand the evolutionary‐scale implications of cave habitat use by dwarf crocodiles.     

Evaluating morphometric and metabolic markers of body condition in a small cetacean,the harbor porpoise (Phocoena phocoena)

Mammalian body condition is an important individual fitness metric as it affects both survival and reproductive success. The ability to accurately measure condition has key implications for predicting individual and population health, and therefore monitoring the population‐level effects of changing environments. No consensus currently exists on the best measure to quantitatively estimate body condition in many species, including cetaceans. Here, two measures of body condition were investigated in the harbor porpoise (Phocoena phocoena). First, the most informative morphometric body condition index was identified. The mass/length² ratio was the most appropriate morphometric index of 10 indices tested, explaining 50% of the variation in condition in stranded, male porpoises with different causes of death and across age classes (n = 291). Mass/length² was then used to evaluate a second measure, blubber cortisol concentration, as a metabolic condition marker. Cortisol is the main glucocorticoid hormone involved in the regulation of lipolysis and overall energy balance in mammals, and concentrations could provide information on physiological state. Blubber cortisol concentrations did not significantly vary around the girth (n = 20), but there was significant vertical stratification through the blubber depth with highest concentrations in the innermost layer. Concentrations in the dorsal, outermost layer were representative of concentrations through the full blubber depth, showed variation by sex and age class, and were negatively correlated with mass/length². Using this species as a model for live cetaceans from which standard morphometric measurements cannot be taken, but from which blubber biopsy samples are routinely collected, cortisol concentrations in the dorsal, outermost blubber layer could potentially be used as a biomarker of condition in free‐ranging animals.     

基于加权Ripley's K-function的多尺度景观格局分析——以江苏盐城滨海湿地为例

以1987,1992,1997,2002,2007年的遥感影像为例,首次尝试使用加权Ripley's K-function的多尺度格局分析方法,计算了20年来景观异质性在江苏盐城滨海湿地的时间变化和空间分布趋势。通过对研究区的样带划分以及景观类型的点状化处理,建立滨海湿地样带图层和1987—2007年间各类型景观的点格局数据库,从而分析滨海湿地不同类型景观的空间聚集特征变化。基于加权Ripley's K-function的计算表明,在各级空间尺度和时间变化上,各类型湿地的斑块都呈现出空间聚集分布状态,且1987年以来,不同湿地类型的聚集空间特征尺度和空间分布强度均出现了大幅的增减变化,除互花米草滩之外的自然湿地的聚集空间特征尺度和强度都有明显下降甚至少到无法被检测到,而人工湿地却呈现聚集特征尺度和强度的双增长,且该聚集程度有逐渐增强的趋势。分析表明,既考虑样点的空间位置信息又考虑样点分布范围的加权Ripley's K-function方法能很好地表征湿地景观在多尺度上的变异,且与传统空间景观指数等分析方法的结论在一定程度上保持一致。     

Effects of shell lesions on survival, growth, condition and reproduction in the New Zealand blackfoot abalone Haliotis iris

The pathogenicity of shell lesions in Haliotis iris Martyn was examined in a laboratory experiment in which 73 apparently healthy and 106 lesion-bearing abalone were maintained for up to 12 mo. The abalone were collected from the wild and kept in cages (1 ind. cage(-1)) for 4, 8 or 12 mo, at which times estimates of survival, growth, condition and reproductive capacity were made for each of 3 groups: 'healthy' (n = 73), 'mildly affected' (n = 61) and 'severely affected' (n = 32). Unaffected abalone showed a 2.7% mortality (n = 73) compared to 7.5% (n = 93) in lesion-bearing individuals over the entire experiment. Growth rates were significantly decreased in mildly and severely affected abalone: the relative von Bertalanffy growth coefficient (K), calculated over 12 mo, was -0.176 for unaffected, -0.079 for mildly affected and -0.048 for severely affected individuals. The asymptotic length (L(infinity)) was calculated to be 131.5 mm for unaffected, 142.1 mm for mildly affected and 150.3 mm for severely affected abalone. Significantly (p < 0.05) lower condition indices and decreased reproductive capacity (p > 0.05) were obtained for the severely affected group compared to unaffected abalone. These trends were consistent over the course of the experiment.     

Ocean warming and hypoxia affect embryonic growth,fitness and survival of small-spotted catsharks,Scyliorhinus canicula

Elasmobranchs are key to a healthy marine ecosystem but are under threat from human activities, such as destructive fisheries and shark finning. Embryos of oviparous elasmobranchs may be further challenged during development by rising temperatures and falling dissolved oxygen concentrations in their intertidal environment. However, the impact of climate change on survival and growth of oviparous elasmobranchs is still poorly understood. Here, we investigate the effects of temperature and hypoxia on the growth and survival of small-spotted catshark (Scyliorhinus canicula) embryos by incubating eggs in normoxia 15°C, normoxia 20°C, hypoxia 15°C, or hypoxia 20°C. Incubation under the elevated temperature increased the embryonic growth rate, yolk consumption rate and Fulton's condition factor at hatching, whilst decreasing the total length and body mass of newly hatched sharks. Under low oxygen conditions (50% air saturation) the survival rate of S. canicula embryos dropped significantly and the temperature-induced increase in Fulton's condition factor was reversed. Together, these data demonstrate both the individual and compound effects of elevated temperature and hypoxia on the survival and growth during early ontogeny of a ubiquitous, coastal elasmobranch, S. canicula.     

卡麦角林处理哺乳期小鼠对子代存活和生长的影响

哺乳期是兽类繁殖成功的关键阶段之一,本实验以不同浓度卡麦角林油溶液对哺乳早期雌性小鼠连续灌胃3 d,检测雌性小鼠体重和幼鼠存活及体重变化,以此确定卡麦角林对哺乳雌性小鼠繁殖成功的影响。结果发现,卡麦角林对雌性小鼠在哺乳期的体重相对增长率无显著影响,但处理组幼鼠出现部分死亡,0 μg / kg、50 μg / kg、100 μg/ kg、200 μg/ kg、400 μg/ kg 组幼鼠死亡率分别为1.30% 、3.85% 、4. 08% 、7.38% 、21.19% ,幼鼠死亡数和剂量呈正相关,400 μg / kg 组幼鼠成活率显著下降到78 8% ,其他剂量组幼鼠成活率与对照组差异不显著;给药后7 d 存活幼鼠的生长发育显著被抑制,之后处理组幼鼠体重变化与对照组无显著差异。上述结果表明卡麦角林处理哺乳早期雌性小鼠可降低幼鼠成活率并抑制存活幼鼠的生长发育,进而有可能降低雌性小鼠及其子代的繁殖成功率。