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71.
Jordan C. Bader Bronte E. Van Helden Paul G. Close Peter C. Speldewinde Sarah J. Comer 《The Journal of wildlife management》2019,83(5):1254-1260
Although critically endangered western ringtail possums (Pseudocheirus occidentalis) have been recorded from a variety of vegetation types in southwestern Australia, the extent to which many of these vegetation types are occupied by the species remains unknown. We conducted spotlight surveys for western ringtail possums between March and April 2018 in Albany, southwestern Australia, to determine the species’ occupancy in 2 vegetation types. Using occupancy models, we demonstrated that sheoak (Allocasuarina fraseriana) woodlands, previously unrecognized as providing western ringtail possum habitat, support the species, although the median probability of their occupancy was lower than in marri (Corymbia calophylla) and eucalypt (Eucalyptus marginata and E. staeri) woodlands. Use of trees and other habitat components by western ringtail possums varied within and between vegetation types. Sheoak woodlands are likely critical for western ringtail possums and given the apparent flexibility in vegetation types used by the species, investigation of the potential value of other vegetation types for this species has conservation merit. © 2019 The Wildlife Society. 相似文献
72.
Per Hedberg Fanny F. Rybak Martin Gullström Narriman S. Jiddawi Monika Winder 《Journal of fish biology》2019,94(1):29-39
Fish larvae abundances, diversity and trophic position across shallow seagrass, coral reef and open water habitats were examined to characterize their distribution in coastal East Africa. Larvae were identified to family and analysed for abundance differences between sites and habitats, trophic level using stable-isotope analysis and parental spawning mode. Abundances differed greatly between sites with the highest numbers of larvae occurring in the open-water and seagrass habitats. Larval fish diversity was high across habitats with 51 families identified with small differences between sites and among habitats. Notably, larvae of abundant large herbivorous fishes present in reef and seagrass habitats were almost completely absent at all sampling locations. In the seagrass, demersal spawned larvae were more abundant compared with the reef and open-water habitats. Stable-isotope analysis revealed that fish larvae have a varied diet, occupying trophic level two to three and utilizing planktonic prey. This study offers new insights into distributional aspects of fish larvae along the East African coast where such information is sparse. 相似文献
73.
Asaf Sharabi 《Anthropological Forum》2019,29(4):356-373
ABSTRACTIn many ethnographies, deities reflect social structures, represent power relations, or serve as a resource for individuals. However, believers usually do not doubt the existence of deities and their agency: that is, their ability to act and initiate change. The gap between these points of view narrows in the religious experiences in the Indian Himalayas. There, the local population, who communicate with local deities via mediums, face an epistemological problem: how to be certain that they are, indeed, talking with their gods. Furthermore, the believers are aware that they play a role in the decisions of the gods. These two aspects of the religious experience are expressed in the gradual transition of the gods from a Pahā?ī to a pan-Hindu identity, an indication of the way in which the agency of the gods is being challenged and is subject to negotiation by the locals. 相似文献
74.
Juliusz Chojnacki 《International Review of Hydrobiology》1983,68(3):435-441
The length weight relationship was determined for Pseudocalanus minutus elongatus, Temora longicornis, Acartia bifilosa, and Acartia longiremis caught in the Pomeranian Bay (Baltic Sea). To determine the weights of the individuals a geometrical method was used and the formula. 相似文献
75.
The paper presents an analysis of the bottom fauna occurrence in the central part of the Gdańsk Deep in the past four decades. In 53% of the samples there were not any bottom invertebrates at all and they periodically disappeared in every decade. At the beginning of the study period, Priapuloidea, Bivalvia, Crustacea and Polychaeta were present in the bottom fauna communities, while only the two latter groups occurred towards the end of the period and the hemipelagic polychaete Harmothoe sarsi was often noted as the only species of the macrozoobenthos. 相似文献
76.
Danielle K. Walkup Anna Michelle Lawing Toby J. Hibbitts Wade A. Ryberg 《Ecology and evolution》2022,12(2)
The western massasauga (Sistrurus tergeminus) is a small pit viper with an extensive geographic range, yet observations of this species are relatively rare. They persist in patchy and isolated populations, threatened by habitat destruction and fragmentation, mortality from vehicle collisions, and deliberate extermination. Changing climates may pose an additional stressor on the survival of isolated populations. Here, we evaluate historic, modern, and future geographic projections of suitable climate for S. tergeminus to outline shifts in their potential geographic distribution and inform current and future management. We used maximum entropy modeling to build multiple models of the potential geographic distribution of S. tergeminus. We evaluated the influence of five key decisions made during the modeling process on the resulting geographic projections of the potential distribution, allowing us to identify areas of model robustness and uncertainty. We evaluated models with the area under the receiver operating curve and true skill statistic. We retained 16 models to project both in the past and future multiple general circulation models. At the last glacial maximum, the potential geographic distribution associated with S. tergeminus occurrences had a stronghold in the southern part of its current range and extended further south into Mexico, but by the mid‐Holocene, its modeled potential distribution was similar to its present‐day potential distribution. Under future model projections, the potential distribution of S. tergeminus moves north, with the strongest northward trends predicted under a climate scenario increase of 8.5 W/m2. Some southern populations of S. tergeminus have likely already been extirpated and will continue to be threatened by shifting availability of suitable climate, as they are already under threat from desertification of grasslands. Land use and habitat loss at the northern edge of the species range are likely to make it challenging for this species to track suitable climates northward over time. 相似文献
77.
Family Raphiophoridae Angelin,1854GenusAbulbaspisgen.nov.Type species Bulbaspis ordosensisLuin Luet al.1976,from the Kli moli Formation(Llanvirn)ofZhuozishan,Wuhai,Inner Mongolia.Diagnosis A raphiophorid genus si milar toAmpyxDal man,1827,but distinguishe… 相似文献
78.
Antibodies were raised against specific peptides from N-terminal regions of the alpha1 and alpha3 isoforms of the GABA(A) receptor, and used to assess the relative expression of these proteins in the superior frontal and primary motor cortices of 10 control, nine uncomplicated alcoholic and six cirrhotic alcoholic cases were matched for age and post-mortem delay. The regression of expression on post-mortem delay was not statistically significant for either isoform in either region. In both cortical areas, the regression of alpha1 expression on age differed significantly between alcoholic cases, which showed a decrease, and normal controls, which did not. Age had no effect on alpha3 expression. The alpha1 and alpha3 isoforms were found to be expressed differentially across cortical regions and showed a tendency to be expressed differentially across case groups. In cirrhotic alcoholics, alpha1 expression was greater in superior frontal than in motor cortex, whereas this regional difference was not significant in controls or uncomplicated alcoholics. In uncomplicated alcoholics, alpha3 expression was significantly lower in superior frontal than in motor cortex. Expression of alpha1 was significantly different from that of alpha3 in the superior frontal cortex of alcoholics, but not in controls. In motor cortex, there were no significant differences in expression between the isoforms in any case group. 相似文献
79.
Determination of antigenic domain in GST fused major surface protein (Nc-p43) of Neospora caninum 总被引:1,自引:0,他引:1
The antigenic domain of the major surface protein (Nc-p43) of Neospora caninum was examined by polymerase chain reaction of its gene fragments and recombinant expression as GST fusion proteins. The fragments of Nc-p43 were as follow: a total open reading frame (OFR), T; OFR without signal sequence and C-terminal hydrophobic sequence, S; N-terminal 2/3 parts of S, A; C-terminal 2/3 parts, P; N-terminal 1/3 part, X; middle 1/3 part, Y; and C-terminal 1/3 part, Z, respectively. The DNA fragments were cloned into pGEX-4T vector. Recombinant plasmids transformed into Escherichia coli of BL21 pLysS (DE3) strain were induced to express GST or GST fused fragments of Nc-p43 such as 69 kDa protein for T, 66 kDa for S, 52 kDa for A, 53 kDa for P, and 40 kDa proteins for X, Y, and Z, respectively in SDS-PAGE. The Nc-p43 fragments of T, S, and P reacted with a bovine serum of neosporosis while those of A, X, Y, and Z together with GST did not in the western blot. These findings suggest that the antigenic domain of Nc-p43 of N. caninum may be localized in the C-terminal 2/3 parts. Together with A19 clone in SAG1 of Toxoplasma gondii (Nam et al., 1996), the P fragment of Nc-p43 could be used as efficient antigens to diagnose and differentiate those infections with both species. 相似文献
80.
Robbins MM Bermejo M Cipolletta C Magliocca F Parnell RJ Stokes E 《American journal of primatology》2004,64(2):145-159
Life-history traits and ecological conditions have an important influence on primate social systems. Most of what we know about the life-history patterns and social structure of gorillas comes from studies of eastern gorillas (Gorilla beringei sp.), which live under dramatically different ecological conditions compared to western gorillas (Gorilla gorilla sp.). In this paper we present new data on western gorilla social structure and life histories from four study sites, and make comparisons with eastern gorilla populations. Data were obtained from two study sites with gorilla groups undergoing the habituation process (Lossi, Democratic Republic of Congo and Bai Hokou, Central African Republic) and two "bai" studies (Maya Nord and Mbeli Bai, Republic of Congo). The size and structure of these groups were similar to those seen in eastern gorillas. However, differences in the occurrence of various group transitions (group formations, changes between one-male and multimale composition, and group disintegrations) exist, and western gorillas notably exhibit much higher rates of male emigration and correspondingly fewer multimale groups compared to mountain gorillas. Certain phenomena have been observed only rarely, including predation by leopards. The preliminary data show no significant differences in birth rates between western gorillas and mountain gorillas. The ecological variability across gorilla habitats likely explains the flexibility in the social system of gorillas, but we need more information on the social relationships and ecology of western gorillas to elucidate the causes for the similarities and differences between western and eastern gorillas on the levels of individuals, social groups, and population dynamics. 相似文献