E. Maurakis, W. Witschey, P. Economidis, D. Bobori
A geographical information system (GIS) for freshwater crabs and fishes in Greece was created in response to the European Environmental Agency's (EEA) biodiversity initiative for European Union countries. A total of 1931 collections, made with seines, dipnets, and backpack electroshockers in 32 drainages of Greece, yielded 126 species of fishes and crabs in 2,359 data records including species, latitude, longitude, drainage, prefecture, and locality; 731 also include stream order, elevation, gradient, stream width and depth, pH, temperature, and distance to river mouth. Our GIS indicates current distributions of species, species rich and poor areas, anomalous species distributions, areas warranting further sampling, and cogeneric species whose overlapping ecoJogical distributions call for taxonomic and phylogenetic investigation. In applied studies, the freshwater GIS can be an integral tool for EEA's biodiversity inventory Qfthe southern Balkan peninsula, an inland fisheries management plan, designs for environmental impact studies, and conducting gap analyses for the region.
{"title":"Creating a Geographical Information System for Freshwater Crabs and Fishes in Greece","authors":"E. Maurakis, W. Witschey, P. Economidis, D. Bobori","doi":"10.25778/MKTN-2X24","DOIUrl":"https://doi.org/10.25778/MKTN-2X24","url":null,"abstract":"A geographical information system (GIS) for freshwater crabs and fishes in Greece was created in response to the European Environmental Agency's (EEA) biodiversity initiative for European Union countries. A total of 1931 collections, made with seines, dipnets, and backpack electroshockers in 32 drainages of Greece, yielded 126 species of fishes and crabs in 2,359 data records including species, latitude, longitude, drainage, prefecture, and locality; 731 also include stream order, elevation, gradient, stream width and depth, pH, temperature, and distance to river mouth. Our GIS indicates current distributions of species, species rich and poor areas, anomalous species distributions, areas warranting further sampling, and cogeneric species whose overlapping ecoJogical distributions call for taxonomic and phylogenetic investigation. In applied studies, the freshwater GIS can be an integral tool for EEA's biodiversity inventory Qfthe southern Balkan peninsula, an inland fisheries management plan, designs for environmental impact studies, and conducting gap analyses for the region.","PeriodicalId":23516,"journal":{"name":"Virginia journal of science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2003-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82127688","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. T. Mengak, S. Castleberry, W. Ford, Nikki L. Castleberry, Jane L. Rodrigue
The Allegheny woodrat (Neotoma magister) is found throughout much of the central and southern Appalachians and adjacent portions of the Interior Highlands. Allegheny woodrats have declined in the northern portions of their range and are state-listed as threatened, endangered or sensitive species of concern in every state where they occur. Until recently, biologists have had to rely on biological data collected from the closely related eastern woodrat (N.jloridana) because oflimited research on the Allegheny woodrat. We have been studying the ecology and natural history ofwoodrats in Virginia and West Virginia since 1990. On 8 August 1997 we caught and ear-tagged a juvenile female woodrat. She was caught a total of 24 times in the same outcrop from 1997 through 2002. A conservative estimate of her age on 25 January 2002 was 1,734 days or 57.8 months. This extends the record longevity for a wild Allegheny woodrat by 70 days or 2.3 months. Regardless, her known time alive (from first capture to last) of 1,630 days still surpasses previous estimates of longevity for the Allegheny woodrat INTRODUCTION The Allegheny woodrat (Neotoma magister) is found throughout much of the central and southern Appalachians and adjacent portions of the Interior Highlands. It is widespread but uncommon in Virginia and West Virginia (Mengak, 1998). It is a habitat specialist closely associated with rock outcrops, cliffs, talus slopes, boulder fields and cave entrances. Allegheny woodrats are tolerant of a wide range of macrohabitats but select specific habitats based on microhabitat features (Castleberry et al., 2002b). The Allegheny woodrats' natural history and role in the local food web and in forest dynamics is unclear. Fungi and mast (hard and soft) are major components of the woodrats diet (Castleberry et al., 2002a) but it is not known what role wo.odrats play, if any, in the distribution of mycorrhizal fungi and forest regeneration. In this ecoregion, the rough and inaccessible areas inhabited by woodrats generally have not been subject to direct, large-scale disturbances from human activities such as logging, agriculture, or second-home development. The long-term effect of disturbances to Corresponding Author: (Phone) 706-583-8096, (E-mail) mmengak@smokey.forestry.uga.edu 168 VIRGINIA JOURNAL OF SCIENCE adjacent habitats on woodrat populations is unclear even as regional land use activities such as forest management and mining continue to increase in intensity. Natural history information on woodrats is needed to assess population status and recommend actions to ensure the long-term survival of this species. Allegheny woodrats have declined in the northern portions of their range and are state-listed as threatened, endangered or sensitive species of concern in every state where they occur (Beans, 1992; Laerm et al. , 2000; Castleberry et al., 2002a). Nonetheless, they still appear to be abundant in appropriate habitat ·in the central Appalachians of Kentucky, Vi
阿勒格尼木鼠(Neotoma magister)遍布阿巴拉契亚山脉中部和南部的大部分地区以及内陆高地的邻近地区。阿勒格尼森林鼠在其活动范围的北部地区已经减少，在它们生长的每个州都被列为受威胁、濒危或敏感物种。直到最近，由于对阿勒格尼木鼠的研究有限，生物学家不得不依靠从密切相关的东部木鼠(N.jloridana)收集的生物数据。自1990年以来，我们一直在研究弗吉尼亚州和西弗吉尼亚州的木鼠生态和自然历史。1997年8月8日，我们捕获了一只年轻的雌性木鼠，并给它贴上了耳标。从1997年到2002年，她在同一露头共被捕获了24次。保守估计她在2002年1月25日的年龄为1734天或57.8个月。这使得野生阿勒格尼木鼠的寿命延长了70天，也就是2.3个月。无论如何，她已知的存活时间(从第一次捕获到最后一次捕获)为1630天，仍然超过了之前对阿勒格尼木鼠寿命的估计。阿勒格尼木鼠(Neotoma magister)分布在阿巴拉契亚山脉中部和南部以及内陆高地邻近地区的大部分地区。它在弗吉尼亚州和西弗吉尼亚州很普遍，但并不常见(Mengak, 1998)。它是一个与岩石露头、悬崖、talus斜坡、巨石场和洞穴入口密切相关的栖息地专家。阿勒格尼木鼠对各种大生境都有耐受性，但会根据微生境特征选择特定的生境(Castleberry et al.， 2002b)。阿勒格尼森林鼠的自然历史和在当地食物网和森林动态中的作用尚不清楚。真菌和桅杆(硬的和软的)是木鼠饮食的主要成分(Castleberry et al.， 2002a)，但它们的作用尚不清楚。如果有的话，蛇在菌根真菌的分布和森林再生中起着作用。在这一生态区域中，木鼠居住的粗糙和难以到达的地区通常不会受到人类活动(如伐木、农业或第二家园开发)的直接、大规模干扰。干扰对通讯作者:(电话)706-583-8096，(电子邮件)mmengak@smokey.forestry.uga.edu 168弗吉尼亚科学杂志邻近栖息地对木鼠种群的长期影响尚不清楚，即使区域土地利用活动(如森林管理和采矿)的强度继续增加。需要关于木鼠的自然历史信息来评估种群状况，并建议采取行动以确保该物种的长期生存。阿勒格尼木鼠在其活动范围的北部地区已经减少，在它们出现的每个州都被列为受威胁、濒危或敏感物种(Beans, 1992;Laerm et al.， 2000;Castleberry et al.， 2002a)。尽管如此，在肯塔基州、弗吉尼亚州和西弗吉尼亚州的阿巴拉契亚中部的适当栖息地，它们似乎仍然大量存在。下降的原因尚不清楚，是争论的主题，但可能包括恶劣的天气(Nawrot和Klimstra, 1976)，鸟类和中哺乳动物捕食增加(Balcom和Yahner, 1996)，消除美洲板栗(Castanea dentata)和毒蛾(Lymantria dispar)在栎林(Quercus spp.)中的侵害所带来的硬杆产量减少(Hall, 1985)，白尾鹿(Odocoileus virginianus)草本象牙的植被变化(Hassinger等，1996)，浣熊蛔虫(Baylis ascaris procyonis)寄生(McGowan and Hicks, 1996)和栖息地破碎化(Balcom and Y ahner, 1996)。直到最近，由于对阿勒格尼木鼠的研究有限，生物学家不得不依靠从密切相关的东部木鼠(N. jl.oridana)收集的生物学数据。然而，最近的许多报告都涉及了阿勒格尼木鼠的生态和自然历史，包括景观特征(Balcom和Yahner, 1996)、种群遗传学(Castleberry等人，回顾)、木材管理的影响(Castleberry等人，2001)、夏季微生境选择(Castleberry等人，2002b)、饮食习惯(Castleberry等人，2002a)、外寄生(Castleberry等人，2002)、繁殖和幼树生长(Mengak, 2002)、和长寿(Mengak, 1997;2000)。通过这篇笔记，我们延长了野生阿勒格尼木鼠的寿命记录，并对繁殖策略进行了评论。此前，野生阿勒格尼森林鼠的寿命纪录分别为1468天和1502天(Mengak, 1997)。另一项长寿记录是1664天(Mengak, 2000)。在Mengak (1997;2000年)报道，圈养的阿勒格尼木鼠的寿命可达48个月(Poole, 1940)。其他关于该属的报道包括野生东部木鼠991天(Fitch and Rainey, 1956)，圈养沙漠木鼠67个月(N。
{"title":"Longevity Record for a Wild Allegheny Woodrat (Neotama magister) in West Virginia","authors":"M. T. Mengak, S. Castleberry, W. Ford, Nikki L. Castleberry, Jane L. Rodrigue","doi":"10.25778/FBAG-VJ45","DOIUrl":"https://doi.org/10.25778/FBAG-VJ45","url":null,"abstract":"The Allegheny woodrat (Neotoma magister) is found throughout much of the central and southern Appalachians and adjacent portions of the Interior Highlands. Allegheny woodrats have declined in the northern portions of their range and are state-listed as threatened, endangered or sensitive species of concern in every state where they occur. Until recently, biologists have had to rely on biological data collected from the closely related eastern woodrat (N.jloridana) because oflimited research on the Allegheny woodrat. We have been studying the ecology and natural history ofwoodrats in Virginia and West Virginia since 1990. On 8 August 1997 we caught and ear-tagged a juvenile female woodrat. She was caught a total of 24 times in the same outcrop from 1997 through 2002. A conservative estimate of her age on 25 January 2002 was 1,734 days or 57.8 months. This extends the record longevity for a wild Allegheny woodrat by 70 days or 2.3 months. Regardless, her known time alive (from first capture to last) of 1,630 days still surpasses previous estimates of longevity for the Allegheny woodrat INTRODUCTION The Allegheny woodrat (Neotoma magister) is found throughout much of the central and southern Appalachians and adjacent portions of the Interior Highlands. It is widespread but uncommon in Virginia and West Virginia (Mengak, 1998). It is a habitat specialist closely associated with rock outcrops, cliffs, talus slopes, boulder fields and cave entrances. Allegheny woodrats are tolerant of a wide range of macrohabitats but select specific habitats based on microhabitat features (Castleberry et al., 2002b). The Allegheny woodrats' natural history and role in the local food web and in forest dynamics is unclear. Fungi and mast (hard and soft) are major components of the woodrats diet (Castleberry et al., 2002a) but it is not known what role wo.odrats play, if any, in the distribution of mycorrhizal fungi and forest regeneration. In this ecoregion, the rough and inaccessible areas inhabited by woodrats generally have not been subject to direct, large-scale disturbances from human activities such as logging, agriculture, or second-home development. The long-term effect of disturbances to Corresponding Author: (Phone) 706-583-8096, (E-mail) mmengak@smokey.forestry.uga.edu 168 VIRGINIA JOURNAL OF SCIENCE adjacent habitats on woodrat populations is unclear even as regional land use activities such as forest management and mining continue to increase in intensity. Natural history information on woodrats is needed to assess population status and recommend actions to ensure the long-term survival of this species. Allegheny woodrats have declined in the northern portions of their range and are state-listed as threatened, endangered or sensitive species of concern in every state where they occur (Beans, 1992; Laerm et al. , 2000; Castleberry et al., 2002a). Nonetheless, they still appear to be abundant in appropriate habitat ·in the central Appalachians of Kentucky, Vi","PeriodicalId":23516,"journal":{"name":"Virginia journal of science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80705837","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Kristine L. Lowe, Ruth E. Fliflet, T. Ly, B. Little, J. Jones-Meehan
Chromium tolerant bacteria were enumerated from portions of the Chesapeake Bay watershed and examined for their potential to reduce Cr(VI). Water and sediment samples were collected from various locations in Baltimore Harbor and Bear Creek, as well as Sandy Point State Park in Maryland and the Anacostia River in Washington, DC. Samples were spread onto agar plates with Cr042-(5 ppm) as the sole terminal electron acceptor. Plates were incubated anaerobically and colony forming units (CFU) enumerated. CFU arising on minimal-Cr042medium ranged from 10 -10 mC or f 1 and community estimates from sites in proximity to Baltimore City were approximately 6-30X higher than distal sites. Bacterial identification by BIO LOGTM or l 68 rRNA sequencing indicated the presence of bacteria of the genera Klebsiella, Pseudomonas, Burkholderia, Kluyvera and others. Typical Cr(VI) reduction rates by these isolates were significantly lower than Shewanella oneidensis, a known metal-reducing bacterium. Results suggested that microbial communities in the Chesapeake Bay watershed, particularly in Baltimore Harbor and Bear Creek, had a high tolerance for Cr(VI) and/or could grow slowly with Cr(VI) as a terminal electron acceptor. However, the isolates did not rapidly degrade Cr(VI) in the laboratory. INTRODUCTION The Chesapeake Bay is the largest estuary in the U.S. and is fed by a broad watershed that includes six states (New York, Pennsylvania, Delaware, Maryland, Virginia and West Virginia) and the District of Columbia, encompassing an area of approximately 12,000 km (Pritchard and Schubel, 2001). Forests, cultivated and abandoned agricultural land, wetlands and residential areas surround the Bay and its adjacent watershed. It is home to a wide range of aquatic wildlife and has regional economic importance in the fishery and shipping industries (Lippson and Lippson, 1997). In addition, the Chesapeake Bay is ·a popular site for recreational boaters and tourists. * To whom correspondence should be addressed. E-mail: jonesmee@cc(nrl.navy.mil; Telephone: (202)404-6361; Fax: (202)404-8515 142 VIRGINIA JOURNAL OF SCIENCE As a result of past and recent human activities, pollutants and other contaminants (i.e., pesticides, herbicides, organophosphates, polychlorinated biphenyls [PCBs], petroleum products and heavy metals) have accumulated in the Bay (Lynch, 2001). Pollutants reach the Bay through river drainage, runoff and direct discharge ( Curtin, 2001 ). One of the more problematic contaminants is chromium, which was mined north of the Bay in the 19th and 20th centuries. Chromium is an important industrial metal used in the manufacture of many diverse products, including ferrous and nonferrous alloys, paints, pigments, wood preservatives and corrosion inhibitors (Fendorf et al., 2000). Such manufacturing industries have operated in and around the Bay region during the past two centuries. Chromium is a redox active transition metal with a wide range of possible oxidation state
{"title":"Chromium Tolerant Microbial Communities from the Chesapeake Bay Watershed","authors":"Kristine L. Lowe, Ruth E. Fliflet, T. Ly, B. Little, J. Jones-Meehan","doi":"10.25778/AS3S-1K32","DOIUrl":"https://doi.org/10.25778/AS3S-1K32","url":null,"abstract":"Chromium tolerant bacteria were enumerated from portions of the Chesapeake Bay watershed and examined for their potential to reduce Cr(VI). Water and sediment samples were collected from various locations in Baltimore Harbor and Bear Creek, as well as Sandy Point State Park in Maryland and the Anacostia River in Washington, DC. Samples were spread onto agar plates with Cr042-(5 ppm) as the sole terminal electron acceptor. Plates were incubated anaerobically and colony forming units (CFU) enumerated. CFU arising on minimal-Cr042medium ranged from 10 -10 mC or f 1 and community estimates from sites in proximity to Baltimore City were approximately 6-30X higher than distal sites. Bacterial identification by BIO LOGTM or l 68 rRNA sequencing indicated the presence of bacteria of the genera Klebsiella, Pseudomonas, Burkholderia, Kluyvera and others. Typical Cr(VI) reduction rates by these isolates were significantly lower than Shewanella oneidensis, a known metal-reducing bacterium. Results suggested that microbial communities in the Chesapeake Bay watershed, particularly in Baltimore Harbor and Bear Creek, had a high tolerance for Cr(VI) and/or could grow slowly with Cr(VI) as a terminal electron acceptor. However, the isolates did not rapidly degrade Cr(VI) in the laboratory. INTRODUCTION The Chesapeake Bay is the largest estuary in the U.S. and is fed by a broad watershed that includes six states (New York, Pennsylvania, Delaware, Maryland, Virginia and West Virginia) and the District of Columbia, encompassing an area of approximately 12,000 km (Pritchard and Schubel, 2001). Forests, cultivated and abandoned agricultural land, wetlands and residential areas surround the Bay and its adjacent watershed. It is home to a wide range of aquatic wildlife and has regional economic importance in the fishery and shipping industries (Lippson and Lippson, 1997). In addition, the Chesapeake Bay is ·a popular site for recreational boaters and tourists. * To whom correspondence should be addressed. E-mail: jonesmee@cc(nrl.navy.mil; Telephone: (202)404-6361; Fax: (202)404-8515 142 VIRGINIA JOURNAL OF SCIENCE As a result of past and recent human activities, pollutants and other contaminants (i.e., pesticides, herbicides, organophosphates, polychlorinated biphenyls [PCBs], petroleum products and heavy metals) have accumulated in the Bay (Lynch, 2001). Pollutants reach the Bay through river drainage, runoff and direct discharge ( Curtin, 2001 ). One of the more problematic contaminants is chromium, which was mined north of the Bay in the 19th and 20th centuries. Chromium is an important industrial metal used in the manufacture of many diverse products, including ferrous and nonferrous alloys, paints, pigments, wood preservatives and corrosion inhibitors (Fendorf et al., 2000). Such manufacturing industries have operated in and around the Bay region during the past two centuries. Chromium is a redox active transition metal with a wide range of possible oxidation state","PeriodicalId":23516,"journal":{"name":"Virginia journal of science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84963304","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Populations of female grass shrimps (Palaemonetes pugio and P. vulgaris) were sampled from five coastal embayments in Delaware, Maryland, and Virginia (Delmarva) and compared with respect to reproductive and life history attributes. We observed interspecific differences in timing ofreproduction, carapace length, ratio of carapace length to total body length, body weight, clutch weight, clutch size, and egg volume. Onset of reproduction in P. vulgaris lagged behind P. pugio. Although there was no difference in the relationship between clutch size and carapace length for the two species, carapace length/total body length in P. pugio was greater than that in P. vulgaris. A multivariate analysis of variance indicated significant differences in carapace length, clutch weight, body weight, clutch size, and egg volume attributable to effects of species, population, and interactions between them. At all sites, P. pugio produced larger eggs than P. vulgaris. Although the two species did not differ in reproductive effort, both species exhibited increases in reproductive effort with latitude. Clutch size also tended to increase with latitude for both species. In populations where both species were abundant, adult females of P. pugio were longer and heavier and produced heavier egg masses comprised of fewer, larger eggs. INTRODUCTION In a classic paper, Hutchinson (1961) raised the issue of how so many similar species are able to coexist in the plankton given the prediction, from the principle of competitive exclusion (Gause, 1934; Hardin, 1960), that one species should outcompete the others. Coexistence of similar species is exemplified by the "grass shrimps" Palaemonetes pugio Holthuis and Palaemonetes vulgaris (Say) that abound in marshes and bays of the Atlantic and Gulf coasts of North America. These two closely related species often co-occur in estuarine sites (Williams, 1984). Although both species exhibit similar distribution patterns across their geographic ranges, they exhibit differences in within-habitat usage. In previous studies, it has been shown that habitat partitioning in these species is a consequence of interspecific differences in physiological tplerances toward salinity (Thorp and Hoss, 1975; Knowlton and Kirby, 1984; Present address: Department of Entomology & Center for Population Biology, One Shields Avenue, University of California, Davis, CA 95616. 2 Corresponding author. 36 VIRGINIA JOURNAL OF SCIENCE Knowlton and Schoen, 1984; Khan et al., 1995, 1997) and dissolved oxygen (Welsh, 1975), substrate and cover preferences (Arguin et al., 1989; Knowlton et al., 1994; Khan et al., 1995, 1997), and interference competition (Thorp, 1976). In the present study, we examine whether differences in reproductive strategies could also promote resource partitioning between P. pugio and P. vulgaris and how these differences are maintained across a range of environmental conditions. There is some evidence to suggest that reproductive strategies di
在美国特拉华州、马里兰州和弗吉尼亚州的5个沿海海湾取样了雌性草虾(Palaemonetes pugio和P. vulgaris)种群，比较了它们的生殖特征和生活史特征。我们观察到种间在繁殖时间、甲壳长度、甲壳长度与体长之比、体重、窝重、窝大小和卵量等方面的差异。在p.p ulgaris繁殖的开始落后于p.p ugio。虽然卵数与甲壳长度的关系无显著性差异，但pugio的甲壳长度/体长大于vulgaris。多变量方差分析表明，不同种类、不同种群及其相互作用对甲壳长度、卵重、体重、卵数和卵体积的影响显著。在所有地点，p.p ugio产的卵都比p.p ulgaris大。尽管两个物种的繁殖努力没有差异，但两个物种的繁殖努力都随着纬度的增加而增加。两个物种的卵群大小也随纬度的增加而增加。在这两个物种都很丰富的种群中，pugio p.p ugio的成年雌性更长、更重，并产生由更少、更大的卵组成的更重的卵团。在一篇经典论文中，Hutchinson(1961)从竞争排斥原理提出了一个问题，即在预测的情况下，浮游生物中如何能够共存这么多相似的物种(Gause, 1934;哈丁，1960)，一个物种应该胜过其他物种。类似物种共存的例子是“草虾”Palaemonetes pugio Holthuis和Palaemonetes vulgaris (Say)，它们大量存在于大西洋和北美海湾沿岸的沼泽和海湾。这两个密切相关的物种经常在河口地区共同出现(Williams, 1984)。尽管这两个物种在其地理范围内表现出相似的分布模式，但它们在栖息地内的利用表现出差异。在以前的研究中，已经表明这些物种的栖息地划分是种间盐度生理耐受差异的结果(Thorp和Hoss, 1975;诺尔顿和柯比，1984;现地址:加州大学戴维斯分校希尔兹大道一号昆虫学系及种群生物学中心，加州95616。2通讯作者。36弗吉尼亚科学杂志诺尔顿和舍恩，1984;Khan et al.， 1995,1997)和溶解氧(Welsh, 1975)，基质和覆盖物偏好(Arguin et al.， 1989;Knowlton et al.， 1994;Khan et al.， 1995,1997)和干扰竞争(Thorp, 1976)。在本研究中，我们研究了繁殖策略的差异是否也会促进p.p pugio和p.p vulgaris之间的资源分配，以及这些差异如何在一系列环境条件下保持。有证据表明，这两个物种的繁殖策略不同。Chambers(1982)和Yan(1987)发现，在相同的繁殖努力(性腺重量与体重之比)下，马萨诸塞州的p.p ugio种群比p.p vulgaris表现出更大的平均卵数。尽管人们认为普吉奥绒螯蟹和俗绒螯蟹的季节繁殖周期相似(Knowlton, 1970)，但Hoffman(1980)观察到，特拉华州的普吉奥绒螯蟹种群在一个季节内产下3窝或更多的卵，而俗绒螯蟹种群在一个季节内产下的卵不超过2窝。在一个物种内，由于温度、光照周期和盐度的差异，生殖特征可能会根据季节和地理位置而变化。在鸟类、鱼类和哺乳动物中已经观察到卵数的纬度曲线，如卵数随纬度增加而增加(Fleming和Gross, 1990)。这种卵窝大小的变化可能反映了生长季节的不同。盐度也可能影响河口生物的卵窝大小。例如，Alon和stanyk(1982)发现p.p ugio的繁殖力随着长时间暴露于较低的盐度而增加。本研究的目的是探讨在多大程度上，这一差异的普吉欧和生殖和检查这些差异在一系列的环境条件。因此，我们比较了P. pugio和P. vulgaris在切萨皮克和弗吉尼亚州、马里兰州和特拉华州的“外”(大西洋)海湾的五个海洋和河口地点的生殖属性，这些地点跨越了很大的盐度梯度和广泛的纬度范围。我们研究了物种和种群水平变异对生殖特征的影响。为了确定繁殖策略的更广泛的地理格局，我们将Delmarva种群的研究结果与其他地区种群的研究结果进行了比较。方法:长叶线虫;
{"title":"Reproductive Differences among Delmarva Grass Shrimp (Palaemonetes pugio and P. vulgaris) Populations","authors":"Holly H. Ganz, R. E. Knowlton","doi":"10.25778/N9CQ-4S17","DOIUrl":"https://doi.org/10.25778/N9CQ-4S17","url":null,"abstract":"Populations of female grass shrimps (Palaemonetes pugio and P. vulgaris) were sampled from five coastal embayments in Delaware, Maryland, and Virginia (Delmarva) and compared with respect to reproductive and life history attributes. We observed interspecific differences in timing ofreproduction, carapace length, ratio of carapace length to total body length, body weight, clutch weight, clutch size, and egg volume. Onset of reproduction in P. vulgaris lagged behind P. pugio. Although there was no difference in the relationship between clutch size and carapace length for the two species, carapace length/total body length in P. pugio was greater than that in P. vulgaris. A multivariate analysis of variance indicated significant differences in carapace length, clutch weight, body weight, clutch size, and egg volume attributable to effects of species, population, and interactions between them. At all sites, P. pugio produced larger eggs than P. vulgaris. Although the two species did not differ in reproductive effort, both species exhibited increases in reproductive effort with latitude. Clutch size also tended to increase with latitude for both species. In populations where both species were abundant, adult females of P. pugio were longer and heavier and produced heavier egg masses comprised of fewer, larger eggs. INTRODUCTION In a classic paper, Hutchinson (1961) raised the issue of how so many similar species are able to coexist in the plankton given the prediction, from the principle of competitive exclusion (Gause, 1934; Hardin, 1960), that one species should outcompete the others. Coexistence of similar species is exemplified by the \"grass shrimps\" Palaemonetes pugio Holthuis and Palaemonetes vulgaris (Say) that abound in marshes and bays of the Atlantic and Gulf coasts of North America. These two closely related species often co-occur in estuarine sites (Williams, 1984). Although both species exhibit similar distribution patterns across their geographic ranges, they exhibit differences in within-habitat usage. In previous studies, it has been shown that habitat partitioning in these species is a consequence of interspecific differences in physiological tplerances toward salinity (Thorp and Hoss, 1975; Knowlton and Kirby, 1984; Present address: Department of Entomology & Center for Population Biology, One Shields Avenue, University of California, Davis, CA 95616. 2 Corresponding author. 36 VIRGINIA JOURNAL OF SCIENCE Knowlton and Schoen, 1984; Khan et al., 1995, 1997) and dissolved oxygen (Welsh, 1975), substrate and cover preferences (Arguin et al., 1989; Knowlton et al., 1994; Khan et al., 1995, 1997), and interference competition (Thorp, 1976). In the present study, we examine whether differences in reproductive strategies could also promote resource partitioning between P. pugio and P. vulgaris and how these differences are maintained across a range of environmental conditions. There is some evidence to suggest that reproductive strategies di","PeriodicalId":23516,"journal":{"name":"Virginia journal of science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82396014","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A colonial cyanoprokaryote, Aphanocapsa holsatica and autotrophic picoplankton abundance were monitored weekly over a two year period in Lake Joyce, Virginia. Significant differences were observed in both the cyanoprokaryote and picoplankton abundance over the study period and an inverse relationship was observed between these two plankton groups. Disaggregation of colonies was shown to contribute to picoplankton populations where water temperature and precipitation input apparently trigger colony dispersion. This relationship is suggested to occur in other aquatic habitats. Results of this work and its implications for ecosystem dynamics are discussed. INTRODUCTION Picoplankton is defined as plankton between 0.2 and 2.0μm in size (Sieburth et al., 1978) and may include a variety of both heterotrophic and autotrophic organisms (Marshall, 2002). Numerous studies have shown picoplankton as an abundant and productive component within a variety of oceanic, estuarine and freshwater environments (Li, et al., 1983; Fahnensteil and Carrick, 1992; Marshall and Nesius, 1993; Affronti and Marshall, 1994). However, questions remain as to the relationship of picoplankton in aquatic food web dynamics (Stockner and Shortreed, 1989; Fogg, 1995; Marshall, 2002). To answer these questions, more detailed information is required on factors which influence picoplankton composition dynamics. With this information, a better understanding of the availability of picoplankton as a link or sink for nutrients can be determined. The objectives of this study are: 1) identify variation in both autotrophic picoplankton and colonial cyanoprokaryotic abundance using a high frequency sampling regime and 2) identify the effects, if any that water temperature and storm water runoff have on colonial cyanoprokaryotic and autotrophic picoplankton population dynamics in Lake Joyce, Virginia. Lake Joyce, Virginia (36° 54' 44" Lat., 76° 7' 19" Long.) is a 60ha freshwater lake whose overflow empties via Pleasure House Creek and the Lynnhaven River into the lower Chesapeake Bay. The Virginia Department of Environmental Quality ( 1994) has described this water body as an unstratified, hypereutrophic system whose average depth is 1.1 m. The major nonpoint source input is from urban storm water runoff. Lake Joyce is representative of other lakes in the Norfolk/Virginia Beach area where its general usage includes fishing, boating, and water skiing. METHODS During this study, three replicate surface grab samples (125 mL) were collected weekly at one station in Lake Joyce over a 24 month period (May 29, 2000 to May 20, 200 VIRGINIA JOURNAL OF SCIENCE Plcoplankton Abundance
在为期两年的时间里，每周对弗吉尼亚州乔伊斯湖的一群蓝藻原核生物、全斑藻和自养小浮游生物的丰度进行监测。在研究期间，蓝藻原核生物和微浮游生物的丰度均存在显著差异，两者之间呈反比关系。在水温和降水输入明显触发群落分散的情况下，群落的分解被证明有助于微浮游生物种群的形成。这种关系似乎也存在于其他水生生境中。讨论了本研究的结果及其对生态系统动力学的影响。微浮游生物被定义为大小在0.2 - 2.0μm之间的浮游生物(Sieburth et al.， 1978)，可能包括各种异养和自养生物(Marshall, 2002)。许多研究表明，在各种海洋、河口和淡水环境中，浮游生物是一个丰富而富有成效的组成部分(Li等，1983;Fahnensteil and Carrick, 1992;Marshall和Nesius, 1993;Affronti and Marshall, 1994)。然而，关于浮游生物在水生食物网动态中的关系的问题仍然存在(Stockner和Shortreed, 1989;福格,1995;马歇尔,2002)。为了回答这些问题，需要更详细地了解影响浮游生物组成动态的因素。有了这些信息，就可以更好地了解微浮游生物作为营养物质的链接或汇的可用性。本研究的目的是:1)利用高频采样制度确定自养微浮游生物和群落蓝藻原核生物丰度的变化;2)确定水温和暴雨径流对弗吉尼亚乔伊斯湖群落蓝藻原核生物和自养微浮游生物种群动态的影响(如果有的话)。弗吉尼亚乔伊斯湖(北纬36°54' 44")(长76°7' 19”)是一个60公顷的淡水湖，其溢流通过欢乐屋溪和林恩黑文河流入切萨皮克湾下游。弗吉尼亚环境质量部(1994)将该水体描述为一个平均深度为1.1米的非分层、富营养化系统。主要的非点源输入来自城市雨水径流。乔伊斯湖是诺福克/弗吉尼亚海滩地区其他湖泊的代表，其一般用途包括钓鱼，划船和滑水。方法在24个月的时间里(2000年5月29日至2000年5月20日)，在乔伊斯湖的一个站点每周收集3个重复的表面抓取样本(125 mL)
{"title":"Environmental Factors Contributing to the Disaggregation of a Colonial Cyanoprokaryote and Its Influence on Picoplankton Abundance within Lake Joyce, Virginia","authors":"L. Affronti, B. Duquette","doi":"10.25778/abd2-8637","DOIUrl":"https://doi.org/10.25778/abd2-8637","url":null,"abstract":"A colonial cyanoprokaryote, Aphanocapsa holsatica and autotrophic picoplankton abundance were monitored weekly over a two year period in Lake Joyce, Virginia. Significant differences were observed in both the cyanoprokaryote and picoplankton abundance over the study period and an inverse relationship was observed between these two plankton groups. Disaggregation of colonies was shown to contribute to picoplankton populations where water temperature and precipitation input apparently trigger colony dispersion. This relationship is suggested to occur in other aquatic habitats. Results of this work and its implications for ecosystem dynamics are discussed. INTRODUCTION Picoplankton is defined as plankton between 0.2 and 2.0μm in size (Sieburth et al., 1978) and may include a variety of both heterotrophic and autotrophic organisms (Marshall, 2002). Numerous studies have shown picoplankton as an abundant and productive component within a variety of oceanic, estuarine and freshwater environments (Li, et al., 1983; Fahnensteil and Carrick, 1992; Marshall and Nesius, 1993; Affronti and Marshall, 1994). However, questions remain as to the relationship of picoplankton in aquatic food web dynamics (Stockner and Shortreed, 1989; Fogg, 1995; Marshall, 2002). To answer these questions, more detailed information is required on factors which influence picoplankton composition dynamics. With this information, a better understanding of the availability of picoplankton as a link or sink for nutrients can be determined. The objectives of this study are: 1) identify variation in both autotrophic picoplankton and colonial cyanoprokaryotic abundance using a high frequency sampling regime and 2) identify the effects, if any that water temperature and storm water runoff have on colonial cyanoprokaryotic and autotrophic picoplankton population dynamics in Lake Joyce, Virginia. Lake Joyce, Virginia (36° 54' 44\" Lat., 76° 7' 19\" Long.) is a 60ha freshwater lake whose overflow empties via Pleasure House Creek and the Lynnhaven River into the lower Chesapeake Bay. The Virginia Department of Environmental Quality ( 1994) has described this water body as an unstratified, hypereutrophic system whose average depth is 1.1 m. The major nonpoint source input is from urban storm water runoff. Lake Joyce is representative of other lakes in the Norfolk/Virginia Beach area where its general usage includes fishing, boating, and water skiing. METHODS During this study, three replicate surface grab samples (125 mL) were collected weekly at one station in Lake Joyce over a 24 month period (May 29, 2000 to May 20, 200 VIRGINIA JOURNAL OF SCIENCE Plcoplankton Abundance","PeriodicalId":23516,"journal":{"name":"Virginia journal of science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75514590","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Antibiotic Resistance Patterns (ARPs) of Enterococcus spp. were used as a phenotypic fingerprint to compare and categorize unknown-source isolates in an impaired segment of the Roanoke River, Roanoke County, Virginia. Antibiotic resistance analysis (ARA) of enterococci has been effectively used to differentiate among sources of fecal contamination in many geographic regions in the United States. Enterococcus spp. were used as a fecal indicator in a library consisting of 1,562 known-source isolates. Two-way analysis indicated that approximately 95% of the unknown-source isolates collected were of animal origin. A 3-way analysis indicated that 61 % of the unknowns were of livestock origin while 34% were of wildlife origin. Of the isolates determined to be of wildlife origin, almost all were from raccoons and geese while enterococci from deer were present at low percentages. For one sample date, 20% of the isolates at one site were of human origin. This bacterial source tracking (BST) data will prove valuable for the development of TMDLs for this impaired waterway. INTRODUCTION To date 3,486 km of the 78,000 km of streams and rivers in Virginia are listed as impaired, with only one third being adequately monitored (FOR VA). The Roanoke River, used as a source of drinking water and recreation, originates in the mountains of Montgomery County, runs eastward through the highly populated areas of Roanoke County, Salem City, and Roanoke City, continues into North Carolina and empties into Albemarle Sound, North Carolina. In the Roanoke area, land usage is both agricultural, on which horses, cattle and other agriculturally important animals are present, as well as urban from which human indicator bacteria may originate. Large numbers of resident geese and ducks as well as other wildlife are also present. Of the 803 stream segments in Virginia that are listed as impaired waters, fecal indicator bacteria are the leading cause of the impairment (DEQ). In the next 10 years, Virginia must develop TMDLs (Total Maximum Daily Load) for 600 impaired segments (DEQ). Public watersheds can be restricted from human recreational use if they exceed the Environmental Protection Agency (EPA) standard of 126 Escherichia coli or 33 Enterococcus colony forming units (cfu) per 100 mL (geometric mean) in fresh water (EPA). Diseases caused by enteric pathogens potentially transmitted through contaminated water include cholera (Vibrio cholerae), gasteroenteritis (Escherichia coli) , giardiasis (Giardia) , salmonellosis and typhoid fever (Salmonella sp.), shigellosis (dysentery, Shigella sp.), and viruses, such as hepatitis A and Norwalk group viruses (Parveen et al., 1999; United States Environmental Protection Agency, 2001). 158 VIRGINIA JOURNAL OF SCIENCE With current water testing procedures, the presence of fecal indicator organisms indicate the presence of fecal material but not the source of the contamination. Transforming a non-point source into a point source is valuable
我们在此报告了来自已知粪便来源的粪便肠球菌ARA，结合判别分析(DA)，有效地预测了从四个罗阿诺克河采样点采集的三个样本日期的分离株来源。我们加强了细菌源追踪方法，并报告了这些日期罗阿诺克河粪便污染的程度和粪便污染的来源。材料与方法细菌文库将已知来源(马、人、浣熊、羊、鸡、牛、白尾鹿、加拿大鹅和麝鼠)的新鲜粪便(从拭子到几克不等)用无菌蒸馏水稀释。来自人类的样本被认为是来自移动厕所或抽水卡车的几个人的分离株的混合物。收集多个粪便样本并混合，而鹅分离物来自单个个体。对几匹马进行了擦洗以获取粪便。将100 L粪便悬浮液移液到每个mEnterococcus agar (Difeo)平板上，并用无菌玻璃曲棍球棒铺匀。倒置，37℃孵育48h。用无菌牙签摘取酒红色和粉红色菌落，置于无菌96孔板中200μL肠球菌肉汤(BBL)中。黑井(肠球菌阳性)。使用48叉式复制板将分离物转移到胰酶大豆琼脂与卵磷脂和聚山梨酸酯80 (BBL)抗生素板上(表1)。抗生素板倒置，在37℃下孵育48小时。抗生素和终盘
{"title":"Identifying Sources of Fecal Pollution in the Roanoke River, Roanoke County, Virginia","authors":"J. Crozier, B. Clark, H. Weber","doi":"10.25778/XEAE-XV83","DOIUrl":"https://doi.org/10.25778/XEAE-XV83","url":null,"abstract":"Antibiotic Resistance Patterns (ARPs) of Enterococcus spp. were used as a phenotypic fingerprint to compare and categorize unknown-source isolates in an impaired segment of the Roanoke River, Roanoke County, Virginia. Antibiotic resistance analysis (ARA) of enterococci has been effectively used to differentiate among sources of fecal contamination in many geographic regions in the United States. Enterococcus spp. were used as a fecal indicator in a library consisting of 1,562 known-source isolates. Two-way analysis indicated that approximately 95% of the unknown-source isolates collected were of animal origin. A 3-way analysis indicated that 61 % of the unknowns were of livestock origin while 34% were of wildlife origin. Of the isolates determined to be of wildlife origin, almost all were from raccoons and geese while enterococci from deer were present at low percentages. For one sample date, 20% of the isolates at one site were of human origin. This bacterial source tracking (BST) data will prove valuable for the development of TMDLs for this impaired waterway. INTRODUCTION To date 3,486 km of the 78,000 km of streams and rivers in Virginia are listed as impaired, with only one third being adequately monitored (FOR VA). The Roanoke River, used as a source of drinking water and recreation, originates in the mountains of Montgomery County, runs eastward through the highly populated areas of Roanoke County, Salem City, and Roanoke City, continues into North Carolina and empties into Albemarle Sound, North Carolina. In the Roanoke area, land usage is both agricultural, on which horses, cattle and other agriculturally important animals are present, as well as urban from which human indicator bacteria may originate. Large numbers of resident geese and ducks as well as other wildlife are also present. Of the 803 stream segments in Virginia that are listed as impaired waters, fecal indicator bacteria are the leading cause of the impairment (DEQ). In the next 10 years, Virginia must develop TMDLs (Total Maximum Daily Load) for 600 impaired segments (DEQ). Public watersheds can be restricted from human recreational use if they exceed the Environmental Protection Agency (EPA) standard of 126 Escherichia coli or 33 Enterococcus colony forming units (cfu) per 100 mL (geometric mean) in fresh water (EPA). Diseases caused by enteric pathogens potentially transmitted through contaminated water include cholera (Vibrio cholerae), gasteroenteritis (Escherichia coli) , giardiasis (Giardia) , salmonellosis and typhoid fever (Salmonella sp.), shigellosis (dysentery, Shigella sp.), and viruses, such as hepatitis A and Norwalk group viruses (Parveen et al., 1999; United States Environmental Protection Agency, 2001). 158 VIRGINIA JOURNAL OF SCIENCE With current water testing procedures, the presence of fecal indicator organisms indicate the presence of fecal material but not the source of the contamination. Transforming a non-point source into a point source is valuable","PeriodicalId":23516,"journal":{"name":"Virginia journal of science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80559950","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ovaries of black drum, Pogonias cromis, collected fromthe Chesapeake Bay region in 1992, were used to describe reproductive strategy and fecundity. Histological examination showed that black drum spawn in the Chesapeake Bay region from April through early June. Distributions of oocyte diameter showed distinct oocyte-developmental groups indicating that Chesapeake Bay black drum are group-synchronous batch spawners. Female black drum are extremely fecund ranging from 414,000 to 3,736,000 hydrated oocytes (mean = 1,389,000) per batch with a spawning periodicity of 3.8 days. Estimates of spawning strategy, spawning periodicity, and batch fecundity for black drum from the Chesapeake Bay region were similar to reported estimates from the Gulf of Mexico. INTRODUCTION In U.S. waters, where the primary range for black drum, Pogonias cromis, in the Northwest Atlantic is from the Delaware .Bay south to Florida and through the Gulf of Mexico (Welsh and Breder, 1923; Hildebrand and Schroeder, 1928; Silverman, 1979), there are at least two known populations: one along the U.S. East Coast and one or more in the Gulf of Mexico (Gold et al. 1995; Jones and Wells 1998). Many essential elements of the reproductive life history are well understood for stocks in the Gulf of Mexico (Fitzhugh et al. , 1993; Nieland and Wilson, 1993; Saucier and Baltz, 1993; Fitzhugh and Beckman, 1987). Specifically, black drum fromthe Gulf of Mexico mature at five years, are group-synchronous spawners, with a batch fecundity of 1.4 to 1.6 million hydrated oocytes, and have a spawning periodicity of 3 4 days (Fitzhugh et al. , 1993; Nieland and Wilson, 1993). In contrast to the Gulf of Mexico black drum, littl~ is known about the reproductive biology of black drum along the U.S. East Coast. Studies of adult black drum in Eastern Florida and in the Chesapeake Bay have been limited to estimating the age at maturity and spawning season. Murphy and Taylor (1989) showed that the age at first maturity is five to six years and the spawning season along Northeast Florida is from January to May with peak spawning in March and April, while Alshuth and Gilmore ( 1995) found a more protracted spawning season from October to late March. In Virginia waters Bobko (1991) observed a spawning season of April through May, and noted that all fish were mature by age six. Although the length of the spawning season and age of maturity have been documented, spawning strategy has not been described nor batch fecundity estimated for black drum from along the U.S. East Coast. Estimates of batch fecundity are essential to understanding life-time reproductive output. However, this information is difficult to obtain because an age-specific migration pattern exists for this population. Although black drum of all ages are present E-mail : bkwellswork@cs.com
本文采用1992年在切萨皮克湾地区采集的黑鼓(Pogonias cromis)的子房来描述其繁殖策略和繁殖力。组织学检查显示，从4月到6月初，黑鼓鱼在切萨皮克湾地区产卵。卵母细胞直径分布显示出不同的卵母细胞发育群体，表明切萨皮克湾黑鼓鱼是群体同步分批产卵者。雌性黑鼓鱼的产卵量非常大，每批次有414,000至3,736,000个水合卵母细胞(平均= 1,389,000)，产卵周期为3.8天。切萨皮克湾地区黑鼓鱼的产卵策略、产卵周期和批量繁殖力的估计与墨西哥湾的报告估计相似。在西北大西洋的美国水域，黑鼓鱼的主要分布范围是从特拉华湾向南到佛罗里达并穿过墨西哥湾(Welsh and Breder, 1923;希尔德布兰德和施罗德，1928;Silverman, 1979)，至少有两个已知的种群:一个在美国东海岸，一个或多个在墨西哥湾(Gold et al. 1995;Jones and Wells, 1998)。墨西哥湾鱼类繁殖生活史的许多基本要素已得到很好的了解(Fitzhugh等人，1993;Nieland and Wilson, 1993;Saucier and Baltz, 1993;菲茨休和贝克曼，1987)。具体而言，墨西哥湾的黑鼓鱼5年成熟，为群体同步产卵，一批产卵量为140 - 160万个水合卵母细胞，产卵周期为34天(Fitzhugh et al.， 1993;Nieland and Wilson, 1993)。与墨西哥湾的黑鼓相比，人们对美国东海岸黑鼓的生殖生物学知之甚少。对佛罗里达东部和切萨皮克湾的成年黑鼓鱼的研究仅限于估计其成熟年龄和产卵季节。Murphy and Taylor(1989)发现初成熟年龄为5 - 6岁，佛罗里达东北部的产卵季节为1 - 5月，高峰期在3 - 4月，而Alshuth and Gilmore(1995)发现产卵季节较长，从10月到3月下旬。在弗吉尼亚水域，Bobko(1991)观察到4月到5月的产卵季节，并注意到所有的鱼在6岁时都成熟了。虽然产卵季节的长度和成熟年龄已经被记录下来，但产卵策略没有被描述，也没有对美国东海岸的黑鼓鱼的批量繁殖力进行估计。估计批次繁殖力对于了解终生生殖产量是必不可少的。然而，这一信息很难获得，因为这一人群存在特定年龄的迁移模式。虽然所有年龄段的黑鼓都在场E-mail: bkwellswork@cs.com
{"title":"Reproduction of Black Drum, Pogonias cromis, from the Chesapeake Bay Region","authors":"B. Wells, Cynthia M. Jones","doi":"10.25778/NCMY-PM70","DOIUrl":"https://doi.org/10.25778/NCMY-PM70","url":null,"abstract":"Ovaries of black drum, Pogonias cromis, collected fromthe Chesapeake Bay region in 1992, were used to describe reproductive strategy and fecundity. Histological examination showed that black drum spawn in the Chesapeake Bay region from April through early June. Distributions of oocyte diameter showed distinct oocyte-developmental groups indicating that Chesapeake Bay black drum are group-synchronous batch spawners. Female black drum are extremely fecund ranging from 414,000 to 3,736,000 hydrated oocytes (mean = 1,389,000) per batch with a spawning periodicity of 3.8 days. Estimates of spawning strategy, spawning periodicity, and batch fecundity for black drum from the Chesapeake Bay region were similar to reported estimates from the Gulf of Mexico. INTRODUCTION In U.S. waters, where the primary range for black drum, Pogonias cromis, in the Northwest Atlantic is from the Delaware .Bay south to Florida and through the Gulf of Mexico (Welsh and Breder, 1923; Hildebrand and Schroeder, 1928; Silverman, 1979), there are at least two known populations: one along the U.S. East Coast and one or more in the Gulf of Mexico (Gold et al. 1995; Jones and Wells 1998). Many essential elements of the reproductive life history are well understood for stocks in the Gulf of Mexico (Fitzhugh et al. , 1993; Nieland and Wilson, 1993; Saucier and Baltz, 1993; Fitzhugh and Beckman, 1987). Specifically, black drum fromthe Gulf of Mexico mature at five years, are group-synchronous spawners, with a batch fecundity of 1.4 to 1.6 million hydrated oocytes, and have a spawning periodicity of 3 4 days (Fitzhugh et al. , 1993; Nieland and Wilson, 1993). In contrast to the Gulf of Mexico black drum, littl~ is known about the reproductive biology of black drum along the U.S. East Coast. Studies of adult black drum in Eastern Florida and in the Chesapeake Bay have been limited to estimating the age at maturity and spawning season. Murphy and Taylor (1989) showed that the age at first maturity is five to six years and the spawning season along Northeast Florida is from January to May with peak spawning in March and April, while Alshuth and Gilmore ( 1995) found a more protracted spawning season from October to late March. In Virginia waters Bobko (1991) observed a spawning season of April through May, and noted that all fish were mature by age six. Although the length of the spawning season and age of maturity have been documented, spawning strategy has not been described nor batch fecundity estimated for black drum from along the U.S. East Coast. Estimates of batch fecundity are essential to understanding life-time reproductive output. However, this information is difficult to obtain because an age-specific migration pattern exists for this population. Although black drum of all ages are present E-mail : bkwellswork@cs.com","PeriodicalId":23516,"journal":{"name":"Virginia journal of science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"91515095","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We assessed the status of furbearing mammals on Fort A.P. Hill, Caroline County, Virginia during the 199 8-1999 trapping season with the cooperation of local licensed trappers. Our analyses were based on 345 captures representing of 10 mammal species, ranging from one bobcat (Lynx rufus) to 157 beavers (Castor canadensis). Mean number of captures per 100 trap nights was 17.0. Captures varied from 11.9 to 17.9 per 100 trap nights for conibear traps and 9.7 to 18.3 per 100 trap nights for leg-hold traps. External measurements of six species were similar to those reported for other populations in the region. We suggest that valuable insights into the ecology and trends of furbearer populations can be obtained from studies conducted on government installations such as Fort A. P. Hill. Management plans that include evaluations of infectious disease reservoirs and transmission and impacts of furbearers on wetlands, other wildlife, and human activities would aid in long-term evaluation of these mammals from ecosystem and health perspectives.
{"title":"A Baseline Assessment of Furbearers on the Upper Coastal Plain of Virginia","authors":"A. Bellows, J. Mitchell","doi":"10.25778/5zts-y543","DOIUrl":"https://doi.org/10.25778/5zts-y543","url":null,"abstract":"We assessed the status of furbearing mammals on Fort A.P. Hill, Caroline County, Virginia during the 199 8-1999 trapping season with the cooperation of local licensed trappers. Our analyses were based on 345 captures representing of 10 mammal species, ranging from one bobcat (Lynx rufus) to 157 beavers (Castor canadensis). Mean number of captures per 100 trap nights was 17.0. Captures varied from 11.9 to 17.9 per 100 trap nights for conibear traps and 9.7 to 18.3 per 100 trap nights for leg-hold traps. External measurements of six species were similar to those reported for other populations in the region. We suggest that valuable insights into the ecology and trends of furbearer populations can be obtained from studies conducted on government installations such as Fort A. P. Hill. Management plans that include evaluations of infectious disease reservoirs and transmission and impacts of furbearers on wetlands, other wildlife, and human activities would aid in long-term evaluation of these mammals from ecosystem and health perspectives.","PeriodicalId":23516,"journal":{"name":"Virginia journal of science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2002-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83847692","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
On December 23-25, 1998, a major ice storm struck southeastern Virginia The storm-deposited glaze ice felled trees and limbs, causing a power outage and highway blockage. Between Februmy and April, 1999, we recorded occurrence, severity, and type of damage to trees over 2.5 cm dbh in nine mostly gently sloping plots in Matoaka Woods at the College of William and Macy. Frequency and severity of damage varied with species and with size of trees. Canopy damage occurred in 75% of large Fagus grandifolia trees, but in only 6% of small Sassafras a/bidum stems. As a group, small (2.5 to 15 cm dbh) trees were less likely to be damaged than large ( 15 cm dbh) trees, but about as likely to be severely damaged. Damage type also varied among the species and size. Despite severe damage to public utilities, damage within the forest was not great. Since few trees lost their entire crown, canopy gap sizes were small, and it not clear that much change in forest composition will result from this storm. However, increased density of ground litter will contribute to greater mineral release, and this plus small gaps may promote growth of already present seedlings and saplings. INTRODUCTION On December 23, 24, and 25, 1998, a major ice storm affected southeastern Virginia. Precipitation in the form of sleet and freezing rain accumulated to 1-3 cm of ice across the region, with Williamsburg reporting 3 cm of precipitation for the three-day period. In the City of Williamsburg and surrounding counties, 400,000 customers lost power for three to ten days following the storm. Many roads, including portions of Interstate 64 near Lightfoot, VA, were rendered impassable by fallen branches and trees (NCDC 1998a,b). The storm's impact on the community was certainly severe, and much of the infrastructure damage was caused by ice-felled branches and trees along roadsides and on forest margins. Based on the degree of damage readily observable from the roads, we felt that this storm presented an ideal opportunity to detennine the effects of ice accumulation on local forests. The great damage to roadside and forest margin trees, however, was due to their peculiar location. Without adjacent vegetation of comparable height to support their accumulated weight in ice, and with either asymmetric or fuller crowns due to lack of competition for light, individuals in the open would likely be more susceptible to damage than those in the forest. Nevertheless, preliminaiy investigation-of our potential study sites indicated that, although the damage within the forest was not as heavy as on its margins, it did appear significantenough t9 provide data for a meaningful study on the dominant tree species of the area. We surmised that the College Woods (also called Matoaka Woods), a forested area owned by the College of William and Macy, was an ideal place for a small-scale 4 VIRGINIA JOURNAL OF SCIENCE investigation into the susceptibility to ice of several major tree species on the Coastal Plain o
1998年12月23日至25日，一场大型冰暴袭击了弗吉尼亚州东南部，风暴沉积的冰霜吹倒了树木和树枝，造成停电和公路堵塞。1999年2月至4月间，我们在威廉和梅西学院Matoaka森林的9个缓坡地块上记录了超过2.5 cm dbh树木的发生情况、严重程度和类型。破坏的频率和严重程度因树种和树木大小而异。75%的大叶子革发生了冠层破坏，而只有6%的小檫树发生了冠层破坏。作为一个整体，小树(2.5 - 15cm dbh)比大树(15cm dbh)更不容易受到损害，但受到严重损害的可能性大致相同。损害类型也因种类和大小而异。尽管公共设施遭到严重破坏，但森林内部的破坏并不大。由于很少有树木失去了整个树冠，冠层间隙大小很小，目前尚不清楚这场风暴是否会导致森林成分发生很大变化。然而，地面凋落物密度的增加将有助于更多的矿物质释放，这加上小的间隙可能促进已经存在的幼苗和树苗的生长。1998年12月23日、24日和25日，一场大型冰暴影响了弗吉尼亚州东南部。整个地区以雨夹雪和冻雨形式的降水累积了1-3厘米的冰，威廉斯堡报告称三天内降雨量为3厘米。在威廉斯堡市及周边县，40万用户在风暴过后断电3到10天。许多道路，包括弗吉尼亚州莱特富特附近64号州际公路的部分路段，都因倒下的树枝和树木而无法通行(NCDC 1998a,b)。风暴对社区的影响当然是严重的，大部分基础设施的损坏是由路边和森林边缘被冰刮倒的树枝和树木造成的。根据从道路上容易观察到的破坏程度，我们认为这场风暴提供了一个理想的机会来确定冰积聚对当地森林的影响。然而，对路边和森林边缘树木的巨大破坏是由于它们的特殊位置。如果没有相邻的高度相当的植被来支撑它们在冰中的累积重量，并且由于缺乏对光的竞争，树冠不对称或更饱满，那么露天中的个体可能比森林中的个体更容易受到伤害。然而，我们对潜在研究地点的初步调查表明，尽管森林内部的破坏不像森林边缘那样严重，但它确实足以为研究该地区的优势树种提供有意义的数据。我们推测学院森林(也叫马托卡森林)是威廉和梅西学院拥有的森林地区，是《弗吉尼亚科学杂志》对弗吉尼亚沿海平原上几种主要树种对冰的易感性进行小规模调查的理想场所。Matoaka森林由各种小而均匀的林分组成，以冠层物种为主，如郁金香杨树(Liriodendron tulipifera)、橡树(Quercus spp.)、山毛榉(Fagus tifolia)和火炬松(Pinus taeda)。树木的马赛克图案(扇形和森林斑块由于各种原因在不同的时间被遗弃或最后被砍伐)允许物种的多样性，也确保了广泛的大小类别的平等代表。在这项研究中，我们的主要目标是衡量对Matoaka森林中每一种更丰富的树种的损害的数量和类型。其次，我感兴趣的是同一物种的不同大小的个体之间的损害比较。方法:1999年2月3日至4月7日，我们在威廉玛丽学院的Matoaka森林进行了实地调查。在圣诞风暴结束和我们的普查完成之间，没有再发生破坏森林的自然现象。根据优势个体的组成种和表观年龄选择采样点，寻找以栎、郁金香杨、火炬松和山毛榉为优势种的林分，比较同一种或属不同树龄林分之间以及不同树种之间的损害情况。采样点广泛分布在整个森林中。我们选择遵循Seischab等人(1993)的方法。我们在每个采样点标记了一个20x40米的地块。为了便于采样，每个子图被分成4个10 × 20米的子图。在每个子样地，大于2.5 cm dbh的树木按物种划分，并被分为两个大小类别:2.5 - 15 cm dbh和大于15 cm dbh。总体上，小尺度的树属于亚冠层，大尺度的树属于冠层。
{"title":"Ice Storm Damage to Virginia Coastal Plain Forests During the Christmas 1998 Ice Storm","authors":"P. Elstner, S. Ware","doi":"10.25778/PCAD-EW27","DOIUrl":"https://doi.org/10.25778/PCAD-EW27","url":null,"abstract":"On December 23-25, 1998, a major ice storm struck southeastern Virginia The storm-deposited glaze ice felled trees and limbs, causing a power outage and highway blockage. Between Februmy and April, 1999, we recorded occurrence, severity, and type of damage to trees over 2.5 cm dbh in nine mostly gently sloping plots in Matoaka Woods at the College of William and Macy. Frequency and severity of damage varied with species and with size of trees. Canopy damage occurred in 75% of large Fagus grandifolia trees, but in only 6% of small Sassafras a/bidum stems. As a group, small (2.5 to 15 cm dbh) trees were less likely to be damaged than large ( 15 cm dbh) trees, but about as likely to be severely damaged. Damage type also varied among the species and size. Despite severe damage to public utilities, damage within the forest was not great. Since few trees lost their entire crown, canopy gap sizes were small, and it not clear that much change in forest composition will result from this storm. However, increased density of ground litter will contribute to greater mineral release, and this plus small gaps may promote growth of already present seedlings and saplings. INTRODUCTION On December 23, 24, and 25, 1998, a major ice storm affected southeastern Virginia. Precipitation in the form of sleet and freezing rain accumulated to 1-3 cm of ice across the region, with Williamsburg reporting 3 cm of precipitation for the three-day period. In the City of Williamsburg and surrounding counties, 400,000 customers lost power for three to ten days following the storm. Many roads, including portions of Interstate 64 near Lightfoot, VA, were rendered impassable by fallen branches and trees (NCDC 1998a,b). The storm's impact on the community was certainly severe, and much of the infrastructure damage was caused by ice-felled branches and trees along roadsides and on forest margins. Based on the degree of damage readily observable from the roads, we felt that this storm presented an ideal opportunity to detennine the effects of ice accumulation on local forests. The great damage to roadside and forest margin trees, however, was due to their peculiar location. Without adjacent vegetation of comparable height to support their accumulated weight in ice, and with either asymmetric or fuller crowns due to lack of competition for light, individuals in the open would likely be more susceptible to damage than those in the forest. Nevertheless, preliminaiy investigation-of our potential study sites indicated that, although the damage within the forest was not as heavy as on its margins, it did appear significantenough t9 provide data for a meaningful study on the dominant tree species of the area. We surmised that the College Woods (also called Matoaka Woods), a forested area owned by the College of William and Macy, was an ideal place for a small-scale 4 VIRGINIA JOURNAL OF SCIENCE investigation into the susceptibility to ice of several major tree species on the Coastal Plain o","PeriodicalId":23516,"journal":{"name":"Virginia journal of science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78218432","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Bellows, J. Mitchell, J. F. Pagels, Heather Mansfield
Fort A.P. Hill (APH) is a 30,329 ha military training installation (U.S. Army) located in the upper Coastal Plain of Caroline County, Virginia. It was formed in 1941 and named in honor of Civil War Confederate Lt. General Ambrose Powell Hill. The current landscape includes a mosaic of habitats that range from old fields to hardwood forests. Forty species of mammals are known to exist on or near the installation. These include one marsupial, five insectivores, 9 chiropterans, one lagomorph, 12 rodents, 10 carnivores, and one cervid. We have studied many of the species on APH since 1997. In this paper w,e describe the physical environment of the area and 7 important habitats used by mammals. We also summarize the ecology and natural history of each species and provide statistical summaries of original measurements from mammals caught on the installation. The results of several recent studies on APH allow us to describe habitat affiliations and relative abundance of most of the mammals native to the mid-Atlantic region. Old fields and clearcuts support a total of 20 species, including several found predominately in this habitat. Pine stands and pine plantations support the fewest number of mammal species (17) of any habitat on the installation. Mixed pine and hardwood forests, hardwood forests, and riparian forests support the largest number of species (29-36). With the possible exception of pine plantations, the habitat mosaic found on APH provides abundant resources for mammal communities. We also include an evaluation of age and health attributes of the deer population and describe the hunting program on the base. Number of deer harvested annually 1985-2000 varied from 460 to 1765. Management activities since 1996 when the deer population exceeded carrying capacity have improved herd health. Because much of Caroline County and eastern Virginia is in extensive agriculture and the remaining hardwood forests are Current address: Deparbnent of Biological Sciences, Old Dominion University, Norfolk, VA 23529. Current e-mail address: abell008@odu.edu. 164 VIRGINIA JOURNAL OF SCIENCE being clearcut, APH is becoming a valuable habitat island for the mammalian fauna of the upper Coastal Plain of Virginia and the mid-Atlantic region.
{"title":"Mammals of Fort A. P. Hill, Caroline County, Virginia and Vicinity","authors":"A. Bellows, J. Mitchell, J. F. Pagels, Heather Mansfield","doi":"10.25778/4XH3-FH93","DOIUrl":"https://doi.org/10.25778/4XH3-FH93","url":null,"abstract":"Fort A.P. Hill (APH) is a 30,329 ha military training installation (U.S. Army) located in the upper Coastal Plain of Caroline County, Virginia. It was formed in 1941 and named in honor of Civil War Confederate Lt. General Ambrose Powell Hill. The current landscape includes a mosaic of habitats that range from old fields to hardwood forests. Forty species of mammals are known to exist on or near the installation. These include one marsupial, five insectivores, 9 chiropterans, one lagomorph, 12 rodents, 10 carnivores, and one cervid. We have studied many of the species on APH since 1997. In this paper w,e describe the physical environment of the area and 7 important habitats used by mammals. We also summarize the ecology and natural history of each species and provide statistical summaries of original measurements from mammals caught on the installation. The results of several recent studies on APH allow us to describe habitat affiliations and relative abundance of most of the mammals native to the mid-Atlantic region. Old fields and clearcuts support a total of 20 species, including several found predominately in this habitat. Pine stands and pine plantations support the fewest number of mammal species (17) of any habitat on the installation. Mixed pine and hardwood forests, hardwood forests, and riparian forests support the largest number of species (29-36). With the possible exception of pine plantations, the habitat mosaic found on APH provides abundant resources for mammal communities. We also include an evaluation of age and health attributes of the deer population and describe the hunting program on the base. Number of deer harvested annually 1985-2000 varied from 460 to 1765. Management activities since 1996 when the deer population exceeded carrying capacity have improved herd health. Because much of Caroline County and eastern Virginia is in extensive agriculture and the remaining hardwood forests are Current address: Deparbnent of Biological Sciences, Old Dominion University, Norfolk, VA 23529. Current e-mail address: abell008@odu.edu. 164 VIRGINIA JOURNAL OF SCIENCE being clearcut, APH is becoming a valuable habitat island for the mammalian fauna of the upper Coastal Plain of Virginia and the mid-Atlantic region.","PeriodicalId":23516,"journal":{"name":"Virginia journal of science","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2001-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89774767","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
京公网安备 11010802042870号
京ICP备2023020795号-1
扫码关注我们
求助内容：
应助结果提醒方式：