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421.
Radio-acoustic positioning as a tool for studying site-specific behavior of the white shark and other large marine species 总被引:1,自引:1,他引:0
A. Peter Klimley Burney J. Le Boeuf Kelly M. Cantara John E. Richert Scott F. Davis S. Van Sommeran 《Marine Biology》2001,138(2):429-446
We describe a method, radio-acoustic-positioning (RAP), for continuously monitoring the movements and behavior of large marine animals. An ultrasonic transmitter on the animal can be localized with high spatial accuracy (2 to 10?m) within an area of 1?km2, based on when the same pulse arrives at three hydrophones on sonobuoys aligned in a triangular array. Radio transceivers communicate with the base station, where the x and y coordinates of the subject are calculated using hyperbolic equations. The base station plots the individual's position and displays information from the tag's sensors in real time on a computer monitor before saving the data on a disk. The base station must be situated either on land or on a vessel within the reception range of the three buoys. We used a RAP system to monitor the movements and behavior of white sharks (Carcharodon carcharias) near the elephant seal rookery at Año Nuevo Island in central California. This type of system is an ideal tool to study the predatory behavior of the white shark because individuals patrol for seal prey within a zone <1300?m from shore. We describe the operation of the system, including acoustic triangulation, range of detection and positioning, data acquisition and analysis, and positional accuracy. We illustrate the implementation of the method and its advantages and disadvantages by describing an ongoing study of white shark hunting-behavior. Sample data from this study are presented to illustrate specific points. We describe the movements of five sharks within the receiving range and their behavior relative to each other. The RAP system is compared to other complementary tracking methods. We conclude that this system has great potential for monitoring the movements and behavior of large marine animals within a relatively small zone, where feeding or reproduction takes place. 相似文献
422.
A. Peter Klimley Burney J. Le Boeuf Kelly M. Cantara John E. Richert Scott F. Davis Sean Van Sommeran John T. Kelly 《Marine Biology》2001,138(3):617-636
The degree to which white sharks, Carcharodon carcharias, are social while hunting is unclear. Our aim was to describe the behavior and interactions among white sharks hunting seals near a seal colony. We attached ultrasonic beacons to five adult white sharks, 4.5–5.2?m long, and recorded their movements and behavior toward each other over a 15-day period in October 1997 at Año Nuevo Island, California. This site is home to colonies of four species of seals and sea lions. Two additional sharks, females 5.5 and 4.7?m in length, were later tracked intensively during periods of 12 and 3?days during October 1998 and November 1999, respectively. We recorded stomach temperature (indicative of feeding on warm-bodied seals) and swimming depths from the 5.5-m female, swimming speed and depth from the 4.7-m female. We monitored the movements and behavior of these sharks using an array of sonobuoys moored near the island; the receptive field measured 1?km2. Our principal findings were: (1) the sharks spent a mean time of 39.5% of each day patrolling within the receptive field; (2) no shark ever moved far out of it; (3) the sharks spent an equal amount of time and activity in the receptive field at all times of the day, daytime, twilight, and nighttime; (4) movements with respect to the island rookery were most often back and forth parallel to the shoreline, (5) tracks of three sharks, tagged at the same time and place, overlapped more often than those of the other two sharks; and (6) some sharks patrolled certain areas in the field preferentially, but there was no conclusive evidence that they defended these areas as territories. Feeding appeared to be infrequent: only two likely feeding bouts occurred during a cumulative 78-day/shark period that individuals were monitored at Año Nuevo Island. The behavior and movements of the sharks were consistent with a hunting strategy, in which individuals search for prey independently but, at the same time, remain close enough to each other to “sense” and exploit a kill by any one of them by joining in on the kill to feed. 相似文献
423.
Surface glycoproteins serve as mate- and gamete-recognition molecules in some marine animals such as rotifers and sea urchins.
We investigated the role of contact chemoreception of surface glycoproteins in mate recognition, mate-guarding, and spermatophore
transfer in the marine harpacticoid Tigriopus japonicus Mori. Adult males accurately distinguished immature females from a pool of mixed-sex juveniles, and their behavior towards
both live and dead females is described. A survey of the binding sites of twelve lectins to the surface of juvenile and adult
females, and adult males demonstrated localized lectin-binding at sites considered important in mating behavior of each sex/age
class. Treating adult males with the Triticum vulgaris lectin sharply inhibited normal mate recognition and guarding behavior, as did the monosaccharide glucosamine. Treatment
of males with protease and detergents destroyed their mate-guarding behavior without affecting swimming behavior. These results
suggest that protein receptors on the antennules of the males detect glycoprotein signals on the surface of females, recognizing
carbohydrate moieties of glycoproteins to identify appropriate partners for guarding or mating. Surface glycoproteins may
function as a common mechanism of sexual communication in many marine zooplankters.
Received: 6 May 1997 / Accepted: 14 September 1997 相似文献
424.
Robert J. Luxmoore William W. Hargrove M. Lynn Tharp Wilfred M. Post Michael W. Berry Karen S. Minser Wendell P. Cropper Jr. Dale W. Johnson Boris Zeide Ralph L. Amateis Harold E. Burkhart V. Clark Baldwin Jr. Kelly D. Peterson 《Environmental Modeling and Assessment》2000,5(2):125-137
Stochastic transfer of information in a hierarchy of simulators is offered as a conceptual approach for assessing forest responses
to changing climate and air quality across 13 southeastern states of the USA. This assessment approach combines geographic
information system and Monte Carlo capabilities with several scales of computer modeling for southern pine species and eastern
deciduous forests. Outputs, such as forest production, evapotranspiration and carbon pools, may be compared statistically
for alternative equilibrium or transient scenarios providing a statistical basis for decision making in regional assessments.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
425.
Basmadjian E Perkins EM Phillips CR Heilprin DJ Watts SD Diener DR Myers MS Koerner KA Mengel MJ Robertson G Armstrong JL Lissner AL Frank VL 《Environmental monitoring and assessment》2008,138(1-3):239-253
The prevalence of toxicopathic liver lesions in demersal fish on the San Pedro Shelf, California was determined for a 15-year
period (1988–2003). Fish livers were sampled at fixed locations as part of the Orange County Sanitation Districts (OCSD) ocean
monitoring program. Histopathological examination of selected fish liver tissues was studied to determine whether the wastewater
discharge had affected fish health. The prevalence of toxicopathic lesion classes neoplasms (NEO), preneoplastic foci of cellular
alteration (FCA), and hydropic vacuolation (HYDVAC) varied among species and locations. For all species sampled, severe lesions
occurred in 6.2% of the fish examined (n = 7,694). HYDVAC (4.1%) was the most common toxicopathic lesion type followed by FCA (1.4%) and NEO (0.7%). HYDVAC occurred
only in white croaker (Genyonemus lineatus), accounting for 84.8% of the toxicopathic lesions for this species. Prevalence of HYDVAC, NEO, and FCA in white croaker
was 15.2, 2.0, and 0.7%, respectively. The prevalence of HYDVAC and NEO in white croaker increased with age and size but there
was no sexual difference. A linear regression model was used for hypothesis testing to account for significant differences
in fish size (and age for croakers) at the different sampling locations. This analysis showed that for HYDVAC there was no
spatial or location effect for lesion rate or size/age of onset. For NEO, the model predicted that white croaker near the
wastewater outfall may acquire these lesions at a smaller size/younger age, and at a higher rate, than at other sites. However,
this result may be biased due to the unequal size frequency distributions and the low prevalence of NEO in white croaker at
the different sampling sites. Bigmouth sole (Hippoglossina stomata) had a prevalence of FCA and NEO of 1.3 and 0.35%, respectively, but the prevalence and distribution of lesions was too few
for statistical testing. There was no sexual difference for lesion prevalence in hornyhead turbot (Pleuronichthys verticalis) and the prevalence of FCA and NEO was 3.4 and 0.37%, respectively. FCA prevalence increased with size in hornyhead turbot
and there were no significant spatial differences for lesion rates and fish size at lesion onset. Overall, consistent spatial
differences for lesion prevalence were not demonstrated and highlight the analytical difficulties of detecting a possible
point source impact when the effect is rare, correlated with the size/age structure of the population, and may be caused by
exposure to unknown multiple sources. Thus, the usefulness of liver histopathology as a point-source monitoring tool is best
applied to where the spatial scale of impact generally exceeds the home range of the target species. 相似文献
426.
Efroymson RA Peterson MJ Welsh CJ Druckenbrod DL Ryon MG Smith JG Hargrove WW Giffen NR Roy WK Quarles HD 《Journal of environmental management》2008,88(4):1436-1451
Habitat valuation methods are most often developed and used to prioritize candidate lands for conservation. In this study the intent of habitat valuation was to inform the decision-making process for remediation of chemical contaminants on specific lands or surface water bodies. Methods were developed to summarize dimensions of habitat value for six representative aquatic and terrestrial contaminated sites at the East Tennessee Technology Park (ETTP) on the US Department of Energy Oak Ridge Reservation in Oak Ridge, TN, USA. Several general valuation metrics were developed for three broad categories: site use by groups of organisms, site rarity, and use value added from spatial context. Examples of use value metrics are taxa richness, a direct measure of number of species that inhabit an area, complexity of habitat structure, an indirect measure of potential number of species that may use the area, and land use designation, a measure of the length of time that the area will be available for use. Measures of rarity included presence of rare species or communities. Examples of metrics for habitat use value added from spatial context included similarity or complementarity of neighboring habitat patches and presence of habitat corridors. More specific metrics were developed for groups of organisms in contaminated streams, ponds, and terrestrial ecosystems. For each of these metrics, cutoff values for high, medium, and low habitat value were suggested, based on available information on distributions of organisms and landscape features, as well as habitat use information. A companion paper describes the implementation of these habitat valuation metrics and scoring criteria in the remedial investigation for ETTP. 相似文献
427.
Pedro Mayor Hani R. El Bizri Thais Q. Morcatty Kelly Moya Nora Bendayán Samantha Solis Carlos F. A. Vasconcelos Neto Maire Kirkland Omar Arevalo Tula G. Fang Pedro E. Pérez-Peña Richard E. Bodmer 《Conservation biology》2022,36(2):e13801
The trade in wild meat is an important economic component of rural people's livelihoods, but it has been perceived to be among the main causes of the decline of wildlife species. Recently, the COVID-19 pandemic has brought to light an additional concern of wildlife markets as a major human-health challenge. We analyzed data from the largest longitudinal monitoring (1973–2018) of the most important urban wild-meat markets in Iquitos, Peru, to examine the trends in and impacts of these markets on people's livelihoods. Over the last 45 years, wild meat sales increased at a rate of 6.4 t/year (SD 2.17), paralleling urban population growth. Wild meat sales were highest in 2018 (442 t), contributing US$2.6 million (0.76%) to the regional gross domestic product. Five species of ungulates and rodents accounted for 88.5% of the amount of biomass traded. Vulnerable and Endangered species represented 7.0% and 0.4% of individuals sold, respectively. Despite growth in sales, the contribution of wild meat to overall urban diet was constant: 1–2%/year of total meat consumed. This result was due to greater availability and higher consumption of cheaper meats (e.g., in 2018, poultry was 45.8% cheaper and was the most consumed meat) coupled with the lack of economic incentives to harvest wild meat species in rural areas. Most wild meat was sold salted or smoked, reducing the likelihood of foodborne diseases. Community-based wildlife management plans and the continued trade bans on primates and threatened taxa may avoid biodiversity loss. Considering the recent COVID-19 pandemic, future management plans should include potential viral hosts and regulation and enforcement of hygiene practices in wild-meat markets. 相似文献
428.
Schirmer Waldir Nagel dos Santos Liliana Andréa Martins Kelly Geronazzo Gueri Matheus Vitor Diniz Jucá José Fernando Thomé 《Journal of Material Cycles and Waste Management》2023,25(5):2887-2899
Journal of Material Cycles and Waste Management - Anaerobic digestion of the organic fraction of municipal solid wastes is a well-established process for biogas production and various forms of... 相似文献
429.
Davis Lodinikki Lemoy Aragão Walessa Alana Bragança de Oliveira Lopes Géssica Eiró Luciana Guimaraes Freire Alexandre Rodrigues Prado Felippe Bevilacqua Rossi Ana Cláudia da Silva Cruz Allan das Graças Fernandes Dantas Kelly Albuquerque Alan Rodrigo Leal Paz Simone Patricia Aranha Angélica Rômulo Simões Lima Rafael Rodrigues 《Environmental science and pollution research international》2022,29(10):13930-13940
Environmental Science and Pollution Research - There are a few data relating to the effects of lead (Pb) exposure on the alveolar bone, which has very distinct morphophysiological characteristics... 相似文献
430.
Liu Zhuling Yang Janet Z. Clark Susan S. Shelly Michael A. 《Environment, Development and Sustainability》2022,24(9):11011-11026
Environment, Development and Sustainability - This study examines the effectiveness of a public service announcement (PSA) video designed based on the theory of planned behavior (TPB) in motivating... 相似文献