海水网箱养殖大黄鱼细菌性病原鉴定与感染治疗研究

从患病大黄鱼的肌肉，肝、肾等病灶中分离出7种菌株，经人工感染试验证明，菌株970709A，970918a和970709B为致病菌，这三株菌株进行人工感染，死亡率均为100％，症状与自然发病相似，经菌体形态特征，生理生化特性反应测定，菌株970909A和970918a为鳗弧菌（Vibrio anguillarum)，菌株970909B为副溶血弧菌（V.parahaemolyticus)，药敏实验结果表明，氧氟沙星，环丙沙星，培氟沙星，罗红霉素，氯霉素和海鱼宁II等对致病菌有较强的抑制作用。临床治疗试验还表明，复方制剂海鱼宁II对大黄鱼弧菌病的治疗效果显著，有效率达66％－68％。     

刺参(Apostichopus japonicus)养殖环境中可培养细菌与理化参数的动态及其相关性分析

随着刺参(Apostichopus japonicus)人工养殖业的快速发展,刺参病害日渐突出.养殖环境微生物和理化参数作为养殖生态系统的重要组成部分,其变化规律及其相关性研究对防治刺参病害具有重要意义.本研究于2012年4月至2013年4月,对山东省即墨市刺参养殖池塘水体中4种可培养细菌(总异养菌、弧菌、硝化细菌、硫化细菌)、4项理化参数(温度、pH、盐度、溶解氧)和沉积环境中6种可培养细菌(总异养菌、弧菌、硝化细菌、硝酸盐还原菌、硫化细菌、硫酸盐还原菌)、6项理化参数(温度、pH、氧化还原电位、硫化物、有机碳、总氮)的动态变化进行了监测,并分析了不同细菌类群的数量及其与沉积物中5项理化指标间的相关性.结果显示:水中大多数细菌类群的周年变化呈夏季高、冬季低的趋势,与温度的变化趋势基本一致,弧菌的变化幅度较异养菌大;硝化细菌较硫化细菌高一个数量级,但变化趋势一致;水体的pH与溶解氧均在夏季高温出现最低值,与温度变化趋势相反;沉积物中异养菌数变化不大,弧菌数量在夏季和冬季出现两个高值.氮循环相关细菌的数量高于硫循环相关细菌.相关性分析结果显示,刺参养殖池塘沉积物的pH与氧化还原电位呈显著正相关(P0.05),二者与硫化物含量均呈极显著负相关(P0.01).硫化物含量与总异养菌、硫酸盐还原菌和硝化细菌均呈极显著正相关(P0.01),与硫化菌和硝酸盐还原菌呈显著负相关(P0.05),总氮含量与硝化细菌正相关性显著(P0.05).各类细菌数量之间也存在一定的相关性:总异养菌与硝化细菌、硫酸盐还原菌之间、硝化细菌与硫酸盐还原菌之间均存在极显著正相关性(P0.01),弧菌与总异养菌、硝化细菌之间存在正相关性,硝酸盐还原菌与硝化细菌之间、硫酸盐还原菌与硫化细菌之间存在负相关性.本研究表明刺参养殖池塘环境中多项理化参数和细菌数量之间相关性显著,其关系错综复杂,可为防治刺参病害提供理论依据.     

海绵体上具有抗肿瘤活性的细菌B2817的分离与鉴定

建立了镰刀菌-细胞毒组合筛选模型,并运用该模型对232株从海绵体上分离出的细菌进行筛选,得到4株抗肿瘤活性较好的细菌.经活性检测,发现菌株B2817的发酵液在稀释100倍时对人肝癌细胞SMMC-7721、人鼻咽癌细胞CNE和小鼠肉瘤细胞S180的抑制率分别为92%、90%和95%,而对正常的人肝细胞的抑制率仅为8%.经多相分类学鉴定,发现B2817是弧菌属中一个种,与弧菌属中的产气弧菌Vibriogazogenes亲缘关系最近,但两者在形态、生理生化特征、分子遗传等方面存在很大差异,故认为B2817可能是弧菌属的一株未被认识的新种.图1表3参9     

大熊猫肠道产果胶酶细菌的多样性及产酶特性

为探究大熊猫肠道微生物与消化的相互关系,利用果胶筛选培养基,从大熊猫新鲜粪便中分离具有产果胶酶活性的细菌,对获得的菌株采用生理生化特征和16S r DNA进行鉴定分类,探讨产果胶酶细菌多样性,并研究菌株的最适生长特性及产酶特性.共分离得到产果胶酶的细菌31株,属于志贺菌属(Shigella)、埃希氏菌属(Escherichia)、克雷伯氏菌属(Klebsilla)3个属,其中最高酶活为334.44 U/m L,最低酶活为15.6 U/m L.PF-4菌株具有最高的酶活,鉴定为肺炎克雷伯氏菌,生长温度范围为16-45℃,生长p H范围是5-8,最适产酶时间为24 h,最适产酶温度为37℃,最适产酶p H为6.结果为研究大熊猫消化系统中微生物果胶酶的来源及性质提供了参考.     

粘细菌的活性检测及与环境因子的相关性

为筛选具有抗菌活性的粘细菌,利用兔粪诱导、大肠杆菌划线诱导和滤纸诱导3种方法从内蒙古凉城地区采集的20种土样中分离粘细菌,结合形态观察、生理生化特征和分子鉴定方法确定这些菌株的分类地位,通过平板对峙法分析抗菌活性,并采用统计学方法分析其与环境因子的相关性.共分离得到140株菌,包括39株纯粘细菌,经鉴定分别为黄色粘球菌(17株)、橙色粘球菌(13株)、变绿粘球菌(5株),还有4株只鉴定到粘球菌属(Myxococcus sp.).抗菌结果显示:39株纯菌均表现出可以对一种甚至多种指示菌产生抗性,其中37株抑制大肠杆菌的生长,35株抑制马铃薯晚疫病菌的生长,26株抑制金黄色葡萄球菌的生长,20株抑制酿酒酵母菌的生长,19株抑制枯草芽孢杆菌的生长.在分析环境因子与粘细菌分布情况的关系时发现,分离出的溶细菌类群的菌株数、溶纤维素类群的菌株数及总的菌株数与土壤p H和速效钾的含量呈正相关,与含水量呈负相关,与其它参数无明显相关性.综上,内蒙古凉城地区粘细菌的优势菌群为粘球菌属,且绝大多数都有不同程度的抗菌活性;结果可为丰富内蒙古地区粘细菌资源及抗马铃薯晚疫病农药研发奠定基础.     

松材线虫对其携带的一株细菌繁殖和致病性的影响

采用黑松(Pinusthunbergii)无菌苗和愈伤组织的接种试验证明,松材线虫携带的洋葱伯克霍尔德氏菌(Burk-holderiacepacia)B619菌株的繁殖及对黑松的致病性受松材线虫的影响.进一步的研究表明,松材线虫的分泌物及死尸均可促进该菌株的生长繁殖和致病作用,且活线虫的促进作用比死尸更加显著,这可能是由于松材线虫提供给该菌株某些重要的营养物质.试验还发现,松材线虫分泌液经高温处理后对致病细菌繁殖的促进活性下降.表5参18     

水体中氧化铁鞘细菌的分离鉴定及保藏

采用试管静止富集培养及生态模拟富集培养，结合平板划线、稀释涂布、平板滴加法，成功地从150份水样中分离到94株鞘细菌．利用Winogradsky液体试管法进行产铁氧化酶鞘细菌的快速初筛，从中筛选出24株产铁氧化酶能力较高的菌株，再经摇瓶复筛，获得产酶活性最高的菌株FC9901．采用多相鉴定方法对菌株FC9901细胞形态、培养特征、生理生化反应及各种碳源利用情况进行了研究，根据《伯杰氏细菌鉴定手册》第9版，把该菌株鉴定为第十四群鞘细菌类(sheathed bacteria)球衣菌属(Sphaerotilus)浮游球衣菌(Sphaerotilus natans)．对鞘细菌几种保藏方法进行比较研究，结果表明蒸馏水保藏法保藏时间长，是一种经济简便有效的保藏方法．图3表7参9     

土壤氨氧化细菌对大气CO2浓度增高的响应

摘要：利用FACE(free．aircarbondioxideenrichment，开放式空气CO2浓度增高)试验平台，研究大气CO2浓度增高对土壤氨氧化细菌的数量、优势菌群及其硝化活性的影响。结果表明，大气CO2浓度增高时，土壤氨氧化细菌的数量在常氮水平上趋于而在高氮水平上与对照没有差异。大气CO2浓度增高对土壤氨氧化细菌的优势菌群也产生明显影响。CO2浓度增高条件下，亚硝化球菌(Nitrosococcus sp.)和亚硝化弧菌(Nitrosovibrio sp．)是优势菌属；而在对照条件下，亚硝化单胞菌(Nitrosomonas sp．)和亚硝化球菌(Nitrosococcus sp．)是优势菌属。另外，CO2浓度增高条件下优势菌株的硝化活性也有不同程度的减弱。     

养殖虾塘常见耐药菌的分离鉴定与耐药基因检测

了解水产养殖区中抗生素耐药菌的分布及抗生素耐药基因的污染现状,有助于科学、合理地使用抗生素。采用诺氟沙星抗性平板和红霉素抗性平板统计虾塘泥样和水样中耐药微生物数量,从中筛选得到60株耐药菌株。基于16Sr DNA序列分析完成部分菌株的鉴定,同时,对耐药菌株携带的喹诺酮类(诺氟沙星)抗性基因gyr A及大环内酯类(红霉素)抗性基因erm B进行了扩增及测序分析。结果表明,虾塘水样细菌在诺氟沙星抗性平板中均未生长,虾塘泥样细菌对诺氟沙星的耐药率分别为0.36%、0.82%;1号虾塘泥样和水样中细菌对红霉素的耐药率分别为23.33%、18.50%,2号虾塘泥样和水样中细菌对红霉素的耐药率分别为20.00%、12.50%。耐药菌16S rDNA鉴定结果如下:南极适冷菌(Rheinheimera sp.)7株、不动杆菌(Acinetobacter sp.)6株、微杆菌(Microbacterium sp.)3株、厦门希瓦氏菌(Shewanella xiamenensis)2株、嗜水气单胞菌(Aeromonashydrophila)2株、豚鼠气单胞菌(Aeromonascaviae)1株。1号虾塘gyr A检出率为43.33%,erm B检出率为30.00%;2号虾塘gyr A检出率为10.00%,erm B检出率为70.00%。耐药基因序列比对结果显示,所测菌株序列与数据库中相应耐药基因序列相似性均≥97%。     

紫花苜蓿根际氢氧化细菌的分离与鉴定

利用气体循环培养体系从陕西乾县HUP-豆科植物紫花苜蓿(Medicago sativa)根际土壤中分离获得37株细菌.菌株氧化氢能力测定结果表明,8株菌氧化氢和自养生长能力较强,初步确定为氢氧化细菌类群;根据其形态特征、培养特征和生理生化特性,鉴定为7个不同属:假单胞菌属(Pseudomonas)、邻单胞菌属(Plesiomonas)、脂肪杆菌属(Pimelobacter)、黄色杆菌属(Xanthobacter)、勒米诺氏菌属(Leminorella)、地杆菌属(Terrabacter)和稀有杆菌属(Rarobacter);其中氧化氢能力最强的优势菌株WMQ-7 16S rDNA序列(GenBank登录号为EU807744)长度为1 451bp,GC含量为53.8%,其核苷酸序列与假单胞菌属同源性高于99%,在系统发育树上位于同一分支,将WMQ-7菌株鉴定为假单胞菌属(Pseudomonas).图2表5参16     

Achieving Open Access to Conservation Science

Conservation science is a crisis discipline in which the results of scientific enquiry must be made available quickly to those implementing management. We assessed the extent to which scientific research published since the year 2000 in 20 conservation science journals is publicly available. Of the 19,207 papers published, 1,667 (8.68%) are freely downloadable from an official repository. Moreover, only 938 papers (4.88%) meet the standard definition of open access in which material can be freely reused providing attribution to the authors is given. This compares poorly with a comparable set of 20 evolutionary biology journals, where 31.93% of papers are freely downloadable and 7.49% are open access. Seventeen of the 20 conservation journals offer an open access option, but fewer than 5% of the papers are available through open access. The cost of accessing the full body of conservation science runs into tens of thousands of dollars per year for institutional subscribers, and many conservation practitioners cannot access pay‐per‐view science through their workplace. However, important initiatives such as Research4Life are making science available to organizations in developing countries. We urge authors of conservation science to pay for open access on a per‐article basis or to choose publication in open access journals, taking care to ensure the license allows reuse for any purpose providing attribution is given. Currently, it would cost $51 million to make all conservation science published since 2000 freely available by paying the open access fees currently levied to authors. Publishers of conservation journals might consider more cost effective models for open access and conservation‐oriented organizations running journals could consider a broader range of options for open access to nonmembers such as sponsorship of open access via membership fees. Obtención de Acceso Abierto a la Ciencia de la Conservación     

Some polyphagous Homoptera gain protection from their natural enemies by feeding on the toxic plantsSpartium junceum andErythrina corallodendrum (Leguminosae)

Summary Interactions were studied among alkaloid-containing legumes (Erythrina corallodendrum andSpartium junceum) and non-toxic plants (Citrus sinensis, Cucurbita moschata andEuphorbia tirucalli), several polyphagous homopterans,Aphis craccivora (Aphididae),Icerya purchasi, I. aegyptiaca (Margarodidae),Lepidosaphes ulmi (Diaspididae) andPlanococcus citri (Pseudococcidae), and some major natural enemies of these homopterans. Significant reductions in survival due to negative effects of alkaloid containing as compared with non-alkaloidal plants were recorded for the predatorsRodolia cardinalis andChilocorus bipustulatus, but not forCryptolaemus montrouzieri (Coleoptera: Coccinellidae),Chrysoperla carnea (Neuroptera: Chrysopidae) andSympherobius sanctus (Neuroptera: Sympherobiidae). The development time of the larvae or pupae ofR. cardinalis, C. carnea andS. sanctus was longer on the toxic plants than on the non-toxic ones. The percentage of parasitism ofA. craccivora collected from the non-alkaloidal plantsVicia palaestina andMelilotus albus was much higher than that onS. junceum. The parasitoid complexes ofA. craccivora differed between both plant groups. The nutritive value of honeydew ofI. purchasi andA. craccivora, as expressed by the life span ofEncyrtus infelix (Hymenoptera: Encyrtidae) adults, was also investigated. Life spans were significantly longer when the wasps fed on honeydew produced on non-alkaloidal plants (C. sinensis andPittosporum tobira) than on alkaloid containing plants whenI. purchasi — but notA. craccivora — was the producer. It is suggested that the chemical defense ofE. corallodendrum andS. junceum is exploited by polyphagous phytophages to reduce predation. In nature, population growth and density of four of the investigated homopterans are conspicuously high when they developed on the alkaloid containing plant species, and very low on non-alkaloid plants. The efficiency of their natural enemies may be reduced by sequestration of alkaloids (or other toxic plant compounds) or their transfer into excreted honeydew. Therefore it is assumed that a generalist phytophagous homopteran may be protected from its natural enemies, although at different rates of efficiency, if it can safely sequester the host allelochemical when it develops on toxic species within its host range.     

Sequestration of cucurbitacin analogs by New and Old World chrysomelid leaf beetles in the tribe Luperini

Summary Two South American polyphagous leaf beetles,Diabrotica speciosa andCerotoma arcuata, selectively accumulated the bitter tasting compound 23,24-dihydrocucurbitacin D in their body after ingesting root tissues of cucurbit plants. Similarly, three Asian Cucurbitaceae-feeding specialists in the genusAulacophora were found to sequester the same compound. Cucurbitacin analogs were shown to deter feeding by a bird predator, indicating an allomonal role for these compounds in cucurbitacin-associated chrysomelid leaf beetles both of New and Old Worlds. The strong affinity to cucurbitacins, selective sequestration of the analogs and consequent protection from predators suggested an ecological adaptation mechanism developed in common among these two geographically isolated subtribes in the Luperini.     

Effects of Controlled Fire and Livestock Grazing on Bird Communities in East African Savannas

Abstract: In East Africa fire and grazing by wild and domestic ungulates maintain savannas, and pastoralists historically set fires and herded livestock through the use of temporary corrals called bomas. In recent decades traditional pastoral practices have declined, and this may be affecting biodiversity. We investigated the effects of prescribed fires and bomas on savanna bird communities in East Africa during the first and second dry seasons of the year (respectively before and after the rains that mark the onset of breeding for most birds). We compared abundance, richness, and community composition on 9‐ha burned plots, recently abandoned bomas, and control plots in the undisturbed matrix habitat over a 3‐year period. Generally, recently burned areas and abandoned bomas attracted greater densities of birds and had different community assemblages than the surrounding matrix. The effects of disturbances were influenced by interactions between primary productivity, represented by the normalized difference vegetation index, and time. Bird densities were highest and a greater proportion of species was observed on burned plots in the months following the fires. Drought conditions equalized bird densities across treatments within 1 year, and individuals from a greater proportion of species were more commonly observed on abandoned bomas. Yearly fluctuations in abundance were less pronounced on bomas than on burns, which indicate that although fire may benefit birds in the short term, bomas may have a more‐lasting positive effect and provide resources during droughts. Several Palearctic migrants were attracted to burned plots regardless of rainfall, which indicates continued fire suppression may threaten their already‐declining populations. Most notably, the paucity of birds observed on the controls suggests that the current structure of the matrix developed as a result of fire suppression. Traditional pastoralism appears critical to the maintenance of avian diversity in these savannas.     

What Every Conservation Biologist Should Know about Economic Theory

Abstract: The last century has seen the ascendance of a core economic model, which we will refer to as Walrasian economics. This model is driven by the psychological assumptions that humans act only in a self‐referential and narrowly rational way and that production can be described as a self‐contained circular flow between firms and households. These assumptions have critical implications for the way economics is used to inform conservation biology. Yet the Walrasian model is inconsistent with a large body of empirical evidence about actual human behavior, and it violates a number of basic physical laws. Research in behavioral science and neuroscience shows that humans are uniquely social animals and not self‐centered rational economic beings. Economic production is subject to physical laws including the laws of thermodynamics and mass balance. In addition, some contemporary economic theory, spurred by exciting new research in human behavior and a wealth of data about the negative global impact of the human economy on natural systems, is moving toward a world view that places consumption and production squarely in its behavioral and biophysical context. We argue that abandoning the straightjacket of the Walrasian core is essential to further progress in understanding the complex, coupled interactions between the human economy and the natural world. We call for a new framework for economic theory and policy that is consistent with observed human behavior, recognizes the complex and frequently irreversible interaction between human and natural systems, and directly confronts the cumulative negative effects of the human economy on the Earth's life support systems. Biophysical economics and ecological economics are two emerging economic frameworks in this movement.     

Effects of Coffee Management on Deforestation Rates and Forest Integrity

Knowledge about how forest margins are utilized can be crucial for a general understanding of changes in forest cover, forest structure, and biodiversity across landscapes. We studied forest‐agriculture transitions in southwestern Ethiopia and hypothesized that the presence of coffee (Coffea arabica)decreases deforestation rates because of coffee's importance to local economies and its widespread occurrence in forests and forest margins. Using satellite images and elevation data, we compared changes in forest cover over 37 years (1973–2010) across elevations in 2 forest‐agriculture mosaic landscapes (1100 km² around Bonga and 3000 km² in Goma‐Gera). In the field in the Bonga area, we determined coffee cover and forest structure in 40 forest margins that differed in time since deforestation. Both the absolute and relative deforestation rates were lower at coffee‐growing elevations compared with at higher elevations (?10/20% vs. ?40/50% comparing relative rates at 1800 m asl and 2300–2500 m asl, respectively). Within the coffee‐growing elevation, the proportion of sites with high coffee cover (>20%) was significantly higher in stable margins (42% of sites that had been in the same location for the entire period) than in recently changed margins (0% of sites where expansion of annual crops had changed the margin). Disturbance level and forest structure did not differ between sites with 30% or 3% coffee. However, a growing body of literature on gradients of coffee management in Ethiopia reports coffee's negative effects on abundances of forest‐specialist species. Even if the presence of coffee slows down the conversion of forest to annual‐crop agriculture, there is a risk that an intensification of coffee management will still threaten forest biodiversity, including the genetic diversity of wild coffee. Conservation policy for Ethiopian forests thus needs to develop strategies that acknowledge that forests without coffee production may have higher deforestation risks than forests with coffee production and that forests with coffee production often have lower biodiversity value. Efectos de la Administración Cafetalera sobre las Tasas de Deforestación y la Integridad de los Bosques     

Globalization of the Cashmere Market and the Decline of Large Mammals in Central Asia

As drivers of terrestrial ecosystems, humans have replaced large carnivores in most areas, and human influence not only exerts striking ecological pressures on biodiversity at local scales but also has indirect effects in distant corners of the world. We suggest that the multibillion dollar cashmere industry creates economic motivations that link western fashion preferences for cashmere to land use in Central Asia. This penchant for stylish clothing, in turn, encourages herders to increase livestock production which affects persistence of over 6 endangered large mammals in these remote, arid ecosystems. We hypothesized that global trade in cashmere has strong negative effects on native large mammals of deserts and grassland where cashmere‐producing goats are raised. We used time series data, ecological snapshots of the biomass of native and domestic ungulates, and ecologically and behaviorally based fieldwork to test our hypothesis. In Mongolia increases in domestic goat production were associated with a 3‐fold increase in local profits for herders coexisting with endangered saiga (Saiga tatarica).That increasing domestic grazing pressure carries fitness consequences was inferred on the basis of an approximately 4‐fold difference in juvenile recruitment among blue sheep (Pseudois nayaur)in trans‐Himalayan India. Across 7 study areas in Mongolia, India, and China's Tibetan Plateau, native ungulate biomass is now <5% that of domestic species. Such trends suggest ecosystem degradation and decreased capacity for the persistence of native species, including at least 8 Asian endemic species: saiga, chiru (Pantholops hodgsoni), Bactrian camel (Camelus bactrianus), snow leopard(Panthera uncia), khulan(Equus hemionus), kiang (E. kiang), takhi (E. przewalski), and wild yak (Bos mutus). Our results suggest striking yet indirect and unintended actions that link trophic‐level effects to markets induced by the trade for cashmere. Globalización del Mercado de Cachemira y la Declinación de Mamíferos Mayores en Asia Central     

The lichen-rich coastal heath vegetation on the isle of Anholt, Denmark — conservation and management

The high conservational value of the lichen-rich vegetation and landscape of the marine foreland Ørkenen on the isle of Anholt is treated from a Danish as well as a European perspective. The sensitivity of the lichen-rich vegetation to physical disturbance is emphasized. The impact of invasive species such asPinus mugo as well as the effect of atmospheric deposition of nutrients on the heaths at Anholt is described. Considerations related to the development of a management plan for Ørkenen are presented.     

Behavior and ecology of Old World Luperini beetles of the genusAulacophora (Coleoptera: Chrysomelidae)

Summary The attraction of Old World leaf beetles in the genusAulacophora to kairomones and parakairomones which are effective lures for New WorldDiabrotica andAcalymma were investigated. Beetles captured on sticky traps baited with single and multicomponent lures were no different from the control traps for two species ofAulacophora. Yellow colored traps and squash blossoms are attractive toAulacophora beetles which detect sub-microgram quantities of cucurbitacins on silica gel. Leaf feeding behavior and flight activity data are correlated with varietal preference of threeAulacophora species. The common response byDiabrotica andAulacophora to cucurbitacins reinforces the two groups' coevolutionary association with the Cucurbitaceae. The apparent lack of a common response toCucurbita blossom volatiles suggests recent evolutionary pathways are substantially different for these two groups of beetles.     

Use of stochastic patch occupancy models in the California red-legged frog for Bayesian inference regarding past events and future persistence

Assessing causes of population decline is critically important to management of threatened species. Stochastic patch occupancy models (SPOMs) are popular tools for examining spatial and temporal dynamics of populations when presence–absence data in multiple habitat patches are available. We developed a Bayesian Markov chain method that extends existing SPOMs by focusing on past environmental changes that may have altered occupancy patterns prior to the beginning of data collection. Using occupancy data from 3 creeks, we applied the method to assess 2 hypothesized causes of population decline—in situ die-off and residual impact of past source population loss—in the California red-legged frog. Despite having no data for the 20–30 years between the hypothetical event leading to population decline and the first data collected, we were able to discriminate among hypotheses, finding evidence that in situ die-off increased in 2 of the creeks. Although the creeks had comparable numbers of occupied segments, owing to different extinction–colonization dynamics, our model predicted an 8-fold difference in persistence probabilities of their populations to 2030. Adding a source population led to a greater predicted persistence probability than did decreasing the in situ die-off, emphasizing that reversing the deleterious impacts of a disturbance may not be the most efficient management strategy. We expect our method will be useful for studying dynamics and evaluating management strategies of many species.