Hasil untuk "Natural history (General)"

Jianfeng Tong, Jianfeng Tong, Jianfeng Tong et al.

Nowadays, most fishing vessels are equipped with high-resolution commercial echo sounders. However, many instruments cannot be calibrated and missing data occur frequently. These problems impede the collection of acoustic data by commercial fishing vessels, which are necessary for species classification and stock assessment. In this study, an automatic detection and classification model for echo traces of the Pacific saury (Cololabis saira) was trained based on the algorithm YOLO v5m. The in situ measurement value of the Pacific saury was measured using single fish echo trace. Rapid calibration of the commercial echo sounder was achieved based on the living fish calibration method. According to the results, the maximum precision, recall, and average precision values of the trained model were 0.79, 0.68, and 0.71, respectively. The maximum F1 score of the model was 0.66 at a confidence level of 0.454. The living fish calibration offset values obtained at two sites in the field were 116.30 dB and 118.19 dB. The sphere calibration offset value obtained in the laboratory using the standard sphere method was 117.65 dB. The differences between in situ and laboratory calibrations were 1.35 dB and 0.54 dB, both of which were within the normal range.

Barbara J. Cade-Menun, Rosalind J. Dodd, Solange Duhamel et al.

Haiwei Zhao, Ruidong Wu, Feiling Yang et al.

Abstract China's Grain for Green Program (GGP) is the largest reforestation program in the world. Previous studies lacked targeted assessments regarding its effectiveness in vegetation conversion. Using the time series of Vegetation Continuous Fields in southwest China, we derived the spatiotemporal variations in total vegetation cover, short vegetation (SV) cover and tree canopy (TC) cover during the period from 2000 to 2016. By conducting residual trend analyses independently on the SV and TC cover time series, the trends in human‐induced SV cover (SVH) and TC cover (TCH) were detected. Then, we performed overlay analyses to derive the human‐induced SV–TC conversion in cropland. The study found that the SV in southwest China showed a net browning trend whereas the TC presented a net greening trend. Approximately 69.5% of the pixels with a significant browning trend in SVH showed a significant greening trend in TCH. Furthermore, 50.6% of the human‐induced SV–TC conversion in southwest China occurred in cropland, and the proportion was even larger for the eastern provinces. Our study provides a targeted evaluation of the performance of the GGP and highlights that the implementation of the GGP has caused widespread SV–TC conversion that potentially mitigates global climate change.

Scott Bennett, Scott Bennett, Raquel Vaquer-Sunyer et al.

Comparative patterns in thermal performance between populations have fundamental implications for a species thermal sensitivity to warming and extreme events. Despite this, within-species variation in thermal performance is seldom measured. Here we compare thermal performance both within-species and between-species, for two species of seagrass (Posidonia oceanica and Cymodocea nodosa) and two species of seaweed (Padina pavonica and Cystoseira compressa) across the Mediterranean Sea. Experimental populations from four locations representing between 75 and 99% of each species thermal distribution and a 6°C gradient in summer temperatures, were exposed to 10 temperature treatments between 15 and 36°C. Experimental thermal performance displayed the greatest variability between species, with optimal temperatures differing by over 10°C within the same location. Within-species differences in thermal performance were also important for P. oceanica which displayed large thermal safety margins within cool and warm-edge populations and small safety margins within central populations. Our findings suggest patterns of thermal performance in Mediterranean seagrasses and seaweeds retain deep “pre-Mediterranean” evolutionary legacies, suggesting marked differences in sensitivity to warming within and between benthic marine communities.

Junpei Shinji, Ryutaro Kamiyama, Tsubasa Nakamura et al.

The importance of local knowledge as a relevant information resource for ecosystem conditions has recently been the focus of sustainable ecosystem management. However, the accuracy of economic evaluation based on local knowledge regarding ecosystems has not yet been discussed, despite most activities in human society, including ecological conservation, being monetarily mediated. This study reports the correspondence between the economic value estimated by the fisher community and the analyzed environmental factors in the marine areas sectioned for oyster farming in Japan. At the study site, community-agreed usage fees for the area sections showed a gradient from the inner to the outer part of the bay. Our numerical modeling showed that the gradient of the economic value correlated with oyster feeding efficiency, indicating that a better location for feeding was empirically evaluated at a high price by the local fisher community. This suggests that the economic evaluation based on the local knowledge was biologically reasonable and could be a reliable information source for the aim of the area use in the study site.

Aylin Ulman, Fadilah Z. Ali, Holden E. Harris et al.

Major invasions of Indo-Pacific lionfish (Pterois volitans and P. miles) are underway in the Western Atlantic Ocean and the Mediterranean Sea. While the establishment of lionfish in the Western Atlantic is perhaps the most well-studied marine fish invasion to date, the rapidly expanding invasion in the Mediterranean is more recent and has received less attention. Here we review and synthesize successes and failures from two decades of lionfish management in the Western Atlantic to give policy recommendations for their management in the Mediterranean. Two failed approaches that were attempted multiple times in the Western Atlantic and that we advise against are (1) feeding lionfish to native fish to promote predation and (2) implementing bounty programs to incentivize lionfish harvest. Broadly, the most important management lessons that we recommend include (1) conducting routine removals by spearfishing with scuba, which can effectively suppress local abundances of lionfish; (2) encouraging the development of recreational and commercial lionfish fisheries, which can promote long-term, sustainable lionfish population control; and, (3) engaging local communities and resource users (e.g., with lionfish removal tournaments), which can concurrently achieve multiple objectives of promoting lionfish removals, market-development, research, and public education. Managers in the Western Atlantic often needed to adapt current conservation policies to enable lionfish removals in areas where spearfishing with scuba was otherwise prohibited for conservation purposes. The risk of abusing these policies was mitigated through the use of gear restrictions, diver trainings, and through participatory approaches that integrated scuba divers and stakeholder organizations in lionfish research and management. Our review of policies and practices in the Mediterranean Sea found that many of our recommended lionfish management approaches are not being done and indicate potential opportunities to implement these. We expect and fully recommend that work continues towards multinational cooperation to facilitate regional coordination of research, control, and management efforts with respect to the Mediterranean lionfish invasion. As with other major biological invasions, lionfish are unconstrained by political borders and their control will require rapid and strategic management approaches with broad cooperation among and between governments and stakeholders.

Wang Huaiyi, Li Zhongkui

[Objective] The research status of watershed ecological compensation was analyzed and mastered in order to provide a basis for improving the compensation system and promoting watershed ecological protection and high-quality development of river basins in China. [Methods] CiteSpace visualization software, Price's law, and the X index were used to analyze 876 studies collected by CNKI for author co-occurrence, high-frequency keywords, and research topic clustering. [Results] Domestic research on watershed ecological compensation mainly began in 2000, and the annual number of publications showed an upward trend. Research hotspots were highly coupled with national policies and watershed development, mainly including quantitative research on watershed ecological compensation standards, research on the behavior of watershed ecological compensation subjects from the perspective of game theory, and research on watershed ecological compensation mechanisms under the background of ecological protection. According to the evolution characteristics of research topics, three stages could be identified: preliminary exploration (before 2007), rapid development (2007—2017), and consolidation and improvement (from 2018 to 2021). During these time periods, research emphasis changed from theoretical analysis to quantitative analysis of compensation standards under the background of water resource governance. The objective of this research focused on the two major water systems of the Yangtze River basin and the Yellow River basin. Researches on the main stream and important tributaries were carried out alternately and gradually deepened. The researches formed multiple basic scientific research platforms, but there were few high-yield authors and little cross sectoral cooperation. [Conclusion] Over the past 20 years, research in the field of watershed ecological compensation in China has formed a certain theoretical system and research framework. The research topics and hot spots have distinctive characteristics, and the research methods have tended to be systematic and diversified. In the future, theory and application should be combined to explore the dynamic and market-oriented compensation mechanisms suitable for regional characteristics.

Elena Lloret-Lloret, Elena Lloret-Lloret, Joan Navarro et al.

Improving the knowledge on the biology, ecology and distribution of marine resources exploited by fisheries is necessary to achieve population recovery and sustainable fisheries management. European hake (Merluccius merluccius) is one of the most important target species in the Mediterranean Sea and is largely overexploited by industrial fisheries. Here, we used two methodological approaches to further investigate the seasonal variation in the spatial distribution of European hake considering ontogenetic changes and trophic ecology in the western Mediterranean Sea. Our main aim was to explore if spatial changes in hake distribution were related to trophic behavior, in addition to key environmental factors. We employed a hierarchical Bayesian species distribution modeling approach (B-SDM), using spatial data from two oceanographic surveys conducted during winter and summer. We analyzed how the environmental variables, together with abundance and mean weight distribution of the main preys identified for European hake, affected the seasonal distribution of the species. Results revealed clear differences in the distribution of the European hake between seasons, which were indeed partially correlated to the distribution of their main preys, in addition to the environment. Stable isotope values and Bayesian isotopic mixing models (MixSIAR) revealed substantial seasonal and ontogenetic differences in trophic habits of European hake, partly matching the spatial distribution results. These findings could have implications for a future seasonal-based adaptive fisheries management, as local depletion of prey, or variation in size and condition may affect European hake presence in this area. Moreover, this study illustrates how the sequential application of methodologies provides a more holistic understanding of species seasonality, which is essential to understand the phenological processes of exploited species and their potential shifts due to environmental changes.

Javier Pinochet, Reinaldo Rivera, Paula E. Neill et al.

The geographical expansion of invasive species depends mainly on its dispersal potential, and the abiotic and biotic factors affecting it. Knowing the invasive dynamic of non-native species, as well as its behavior at different natural or anthropogenic scenarios, is fundamental for planning conservation management policies and control plans. The invasive sea anemone Anemonia alicemartinae in habits from the north (18°S) to the south-central (36°S) coast of Chile and its distribution range has expanded by approximately 1,928 km in the last 50 years. Previous works have proposed that human-mediated southward transport associated with regional-scale maritime activities could explain its rapid spread. To evaluate this hypothesis, we used ecological niche models (ENM) to evaluate the potential colonization of the southernmost area of South America. Additionally, we conducted a post hoc analysis to evaluate the relationship between the prediction of the ENM and human activity measured as the number of landings of ships in ports. The models were built based on presence records of A. alicemartinae, and oceanographic variables. Results showed that sea surface salinity and annual sea surface temperature (variance) are the best predictor variables to explain the distribution of A. alicemartinae. There was a positive and significant relationship between the geographical distribution of the sea anemone predicted by the ENM and the number of landings, as a proxy of anthropogenic activity. The most susceptible areas to invasion were those that showed the highest variability in both oceanographic predictors. These areas included the Biobío region, Chiloé´s inland sea, Aysén, and Chacabuco regions, which together comprise two biogeographical provinces. These results sustain the proposed hypothesis and, overall, the results suggest that along with the characteristics of the life history of A. alicemartinae, oceanographic conditions and maritime transport as vector contribute to the southern range expansion of this invasive cryptogenic species in the Humboldt-current large marine ecosystem.

Paolo G. Albano, Piet A. J. Bakker, Bruno Sabelli

We revise the type specimens of 132 nominal species of worldwide Triphoridae stored in the Natural History Museum of the United Kingdom (NHMUK), London. We provide the species name in its original combination, followed by bibliographic details of the original description, the location of the known type material, the original description (and its translation when in Latin), a diagnosis and curatorial or nomenclatural notes. We illustrated most specimens in the type series in colour and with SEM imaging and we have added the original figure whenever possible. The specimens of Triphoris alveolatus, T. granulatus, T. suturalis and T. verrucosus, all A. Adams & Reeve, 1850, T. pfeifferi Crosse & Fischer, 1865 and T. cucullatus de Folin, 1867, previously considered type material, are not considered here belonging to the type series. Adams & Reeve’s taxa should be considered nomina dubia. The name Triphora insularum is a manuscript name by H.E.J. Biggs who deposited “types” in the NHMUK but refrained from introducing the name due to the lack of apex of the studied material. We selected lectotypes for six species (T. concors Hinds, 1843, T. maxillaris Hinds, 1843, T. fuscomaculata E.A. Smith, 1904, T. shepstonensis E.A. Smith, 1906, T. eupunctata G.B. Sowerby III, 1907, and T. rufula Watson, 1886) to stabilize the nomenclature. Finally, we illustrate original specimens (although not types) of three species described by Turton, whose type material is lost.

Yu. Furyk

The data on malacological collections stored in four natural depositories of Ukraine is analyzed. These museums are as follows: State Natural History Museum, Lviv; malacological col-lection by Prof. V. Zdun, stored in the of the Benediсt Dybowski Zoological Museum of the Ivan Franko National University of Lviv; Ivan Franko Zhytomyr State University and National Museum of Natural History of the Academy of Sciences of Ukraine (Kyiv). Gastropod and bivalve mollusks collected in the late 20th and in the early 21th century within the Tisa River basin (Transcarpathian) are concerned. Basing on catalogues as well as vouchers studied altogether 51 species is listed (9 of class Gastropoda and 4 of class Bivalvia). Also, the article gives data on the numerical representa-tion of these species in the above mentioned collections. This article represents the first paper on a series of articles devoted to the study of the malacological fauna of the Transcarpathian region.

Tashi Dhendup

<p>The Asiatic Golden Cat is a Near Threatened wild cat species as listed by the IUCN. Being a lesser studied species, there is a general paucity of data and hence, global assessment of its true status has been very difficult. In Bhutan, available information on this species is mainly from biodiversity surveys on big mammals such as Tiger and Snow Leopard. A modest attempt has been made to review all available literature on Asiatic Golden Cat in Bhutan and abroad to describe the current status of the species in the country and the need for further studies.</p><div> </div>

A. Munirathinam, R. Krishnamoorthi, G. Baskaran et al.

<p>After a gap of 25 years the Centre for Research in Medical Entomology (CRME) surveyed the mosquito biodiversity in the tail-end hill ranges of the Western Ghats, viz., Kanyakumari (Keeriparai) and Tirunelveli districts (Kalakkad-Mundanthurai Tiger Reserve (KMTR) and Courtallam) of Tamil Nadu between July 2010 and June 2013.  The altitude of the hills ranged from 100–950 m covered by evergreen forests.  A major emphasis was given to collect the immature stages of mosquitoes, from various breeding habitats, viz., slow flowing streams, spring pool, rocky pool, leaf axils, latex cup, tree hole, bamboo stumps, etc.  Altogether 4602 immature individuals were collected, reared individually to be identified at the adult stage.  A total of 3583 specimens belonging to 50 species classified under 21 genera and 18 subgenera were recorded.  The major vector species found in these hill ranges were <em>Stegomyia aegypti, S. albopicta</em> (Dengue and Chikungunya), <em>Culex bitaeniorhynchus, C. tritaeniorhynchus </em>(Japanese encephalitis), <em>Downsiomyia nivea</em> (diurnally subperiodic filariasis) and <em>Anopheles mirans</em> (Simian malaria) vectors were recorded.</p><div> </div>

Shuihua Chen, Zhongyong Fan, Daniel D. Roby et al.

Synergistic effect refers to simultaneous actions of separate factors which have a greater total effect than the sum of the individual factor effects. However, there has been a limited knowledge on how synergistic effects occur and individual roles of different drivers are not often considered. Therefore, it becomes quite challenging to manage multiple threatening processes simultaneously in order to mitigate biodiversity loss. In this regard, our hypothesis is, if the traits actually play different roles in the synergistic interaction, conservation efforts could be made more effectively. To understand the synergistic effect and test our hypothesis, we examined the processes associated with the endangerment of critically endangered Chinese Crested Tern (Thalasseus bernsteini), whose total population number was estimated no more than 50. Through monitoring of breeding colonies and investigations into causative factors, combined with other data on human activities, we found that widespread human harvest of seabird eggs and increasing frequency of typhoons are the major factors that threatened the Chinese Crested Tern. Furthermore, 28 percent of breeding failures were due to the synergistic effects in which egg harvest-induced renestings suffered the higher frequent typhoons. In such combined interactions, the egg harvest has clearly served as a proximal factor for the population decline, and the superimposition of enhanced typhoon activity further accelerated the species toward imminent extinction. Our findings suggest that species endangerment, on one hand, should be treated as a synergistic process, while conservation efforts, on the other hand, should focus principally on combatting the threat that triggers synergistic effects.

S.R. Ganesh, E. Ramanujam

Rediscovery of a rare venomous snake after nearly two centuries (since R.H.Beddome's period). Provides revised diagnosis for the species and updates the congener-comparison. Highlights the lack of taxonomic studies in south Indian coral snakes, particularly the striped coral snake sp. Complex.

Enrique R Laffont

The mound- building termite Nasutitermes coxipoensis is commonly found at subtropical environments of northeast Argentina. This study gives new data about its nest architecture, biology and nutritional habits, comparing these results with other populations of the species. The volume of the analyzed nests varied between 0.91 dm3 y 207.33 dm3, a wider range than previously reported for N. coxipoensis. The external and internal characteristics of the nests were similar to descriptions from other sites although it was not possible to differentiate the royal cell. The societies were monogynic and the queens laid eggs throughout the year. The body length and weight of primary reproductives were reported. The presence of alates within the mounds was higher in October and November. Feeding substrates consumed by N. coxipoensis at these habitats are also reported.

Jared F. Duquette, Jerrold L. Belant, Dean E. Beyer Jr. et al.

Abstract Ketamine and xylazine are an effective chemical combination for white‐tailed deer (Odocoileus virginianus) immobilization, but the effects of body condition on ketamine–xylazine efficacy have not been examined. We assessed the influence of ketamine dosage, xylazine dosage, body condition, age class, and injection site on successful adult female deer chemical immobilization. From January to March 2009–2011, we captured 87 deer (age ≥1.5 yr) in Clover traps and immobilized them using ketamine–xylazine ratios of 400 mg (n = 58) or 300 mg (n = 29) of ketamine to 100 mg of xylazine. Mean deer body mass was 67.8 kg (SD = 12.3, range = 43.0–93.0). We considered immobilization successful if deer induction was achieved ≤15 minutes from first ketamine–xylazine injection. Seventy‐five percent of injected deer (81% with 400:100 mg ketamine:xylazine; 62% with 300:100 mg ketamine:xylazine) achieved successful induction. We recorded deer heart rate, respiration rate and rectal temperature at 0 minutes, 10 minutes, and 20 minutes post‐induction. Comparison of 7 generalized linear models indicated that the probability of successful induction increased by about 6.7% with every 1.0 mg/kg increase in ketamine dosage and by about 0.7% with every 1‐unit decrease in body‐condition index. The remaining parameters did not influence the success of deer induction. Deer heart rate, respiration rate, and rectal temperature decreased over time post‐induction, with >95% within reported ranges for ketamine–xylazine immobilization. We suggest that deer weighing ≤93.0 kg be injected with 5.8 mg/kg ketamine and 1.6 mg/kg xylazine to produce satisfactory induction when using similar capture methods during winter. © 2012 The Wildlife Society.

Warren R. Dawson