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41.
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The majority of the freshwater fishes in the ornamental trade now originate from captive‐bred sources, as do a large proportion of the freshwater species exhibited in public aquariums. In contrast, commercial operators who also supply marine specimens to the ornamental trade remove directly from the wild approximately 98% of the marine fishes and invertebrates exhibited in public aquariums. The common perception prevails that captive propagation is inherently a better alternative to obtaining animals from the wild. Although captive propagation has been shown to have many benefits for terrestrial species, there are a number of features unique to marine species that challenge the idea that every species should be bred in captivity. Some of the key issues relating to the development of widespread conservation‐oriented captive propagation programs include: 1) the high taxonomic diversity in marine animals; 2) the resultant variety in their reproductive methods; 3) their ecological, behavioral, physiological, and nutritional needs; and 4) our general lack of knowledge on their husbandry and medical care. There are several characteristics of marine fish and invertebrate populations that make them suitable candidates for sustainable harvest. For instance, marine teleosts are “r‐selected,” meaning that they have an extremely high fecundity, and most marine teleosts have a wide distribution and the ability to disperse over long distances. In locations considered for fish collection, appropriate management techniques should be employed to ensure that fishes and invertebrates are collected with as little impact on the ecosystem as possible. The collection of marine fishes and invertebrates for public aquariums and the hobby trade should be managed like a fishery to ensure long‐term sustainability. The public aquarium community should support marine organism certification initiatives, such as the Marine Aquarium Council (MAC). Marine organism certification will create market incentives that encourage and support quality and sustainable practices by creating consumer demand and confidence for certified organisms, practices, and industry participants. The creation of refuges that supply propagules to harvested areas, the rotation of areas fished, species‐specific size limits and seasons, and standardization of collecting, handling, and transportation techniques should be used to manage these fisheries and harvest areas. Zoo Biol 22:519–527, 2003. © 2003 Wiley‐Liss, Inc. 相似文献
43.
In Portugal there are few culture collections of filamentous fungi and these are mostly in-house, and located mainly in the Lisbon area. Furthermore, open access to Portuguese databases on microorganisms is not well established. This knowledge and the continuing experimental activity in mycology, combined with an interest from the University in creating and financing reliable services to support research, led to the organization of a filamentous fungal culture collection, hosted at the Biological Engineering Centre of Minho University, in the North of Portugal. The Micoteca da Universidade do Minho (MUM), was established in 1996, with the aim of maintaining and providing strains for research on biotechnology and for use in teaching laboratories, and to act as a centre of expertise, information and training, complying with international quality standards. The use of a computerized system for the management of recorded data and the collection's holdings was envisaged from the start. The collection now holds 128 identified species, including recognized standard or test strains and isolates derived from research activities, mainly of the genera Penicillium and Aspergillus. The microbial strain database was built in-house and runs on Windows 2000. To ensure widespread availability of details of the collection's holdings, the fields intended for general searching and viewing are available on-line at http://www.micoteca.deb.uminho.pt/. 相似文献
44.
W. J. Kress W. R. Heyer P. Acevedo J. Coddington D. Cole T. L. Erwin B. J. Meggers M. Pogue R. W. Thorington R. P. Vari M. J. Weitzman S. H. Weitzman 《Biodiversity and Conservation》1998,7(12):1577-1587
Data from 3991 records of museum collections representing 421 species of plants, arthropods, amphibians, fish, and primates were analyzed with GIS to identify areas of high species diversity and endemism in Amazonia. Of the 472 1 × 1° grid cells in Amazonia, only nine cells are included in the highest species diversity category (43–67 total species) and nine in the highest endemic species diversity category (4–13 endemic species). Over one quarter of the grid cells have no museum records of any of the organisms in our study. Little correspondence exists between the centers of species diversity identified by our collections-based data and those areas recommended for conservation in an earlier qualitative study of Amazonian biodiversity. Museum collections can play a vital role in identifying species-rich areas for potential conservation in Amazonia, but a concerted and structured effort to increase the number and distribution of collections is needed to take maximum advantage of the information they contain. 相似文献
45.
J. P. W. Scharlemann 《International journal of biometeorology》2001,45(4):208-211
Museum collections hold large amounts of data on collecting dates and localities of eggs collected over the past 150 years.
Egg collections hold the longest available time series for a wide range of bird species on a large spatial scale. Using data
for two British species I investigate whether egg collection data can be used in phenological research. A method is presented
allowing laying dates to be estimated from collecting dates. Problems and biases in the data are highlighted. Both the dipper
and song thrush have started laying earlier over the past 150 years. The advance in laying is significantly correlated with
mean March temperature.
Received: 25 October 2000 / Revised: 14 May 2001 / Accepted: 16 May 2001 相似文献
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The Department of Invertebrate Zoology at the SantaBarbara Museum of Natural History houses a smallcollection of nemerteans from the Eastern PacificOcean. At present the collection containsapproximately 2000 specimen lots stored in alcohol. The historically important elements of the collectionwere obtained in transfers from the Allan HancockFoundation of the University of Southern California,the Kerkoff Marine Laboratory of the CaliforniaInstitute of Technology, and the Benthic InvertebrateMuseum of Scripps Institution of Oceanography. Thespecimens in these three collections voucher manyof the species treated in Wesley R. Coe's 1940revision of the nemerteans of the west coast of theAmericas. Type specimens were located for 4 of the 5new species group taxa and for 1 new subspecies grouptaxon erected in that publication. The Allan HancockFoundation material utilized by Coe was collected inthe 1930's during Pacific expeditions of the R/V Velero III. The material assembled by George andNettie MacGinitie at the Kerkoff lab contained anumber of specimens collected during the same timeperiod. The specimens from Coe's material at ScrippsInstitution of Oceanography were collected by TheodoreBullock and students in central California in 1939. 相似文献
48.
Microcystins (MCN), β-N-methylamino-L-alanine (BMAA) and anatoxin-a were investigated in Antarctic cyanobacterial mats collected from Ross Island and the McMurdo Ice Shelf, East Antarctica during Captain Scott’s ‘Discovery’ National Antarctic Expedition (1901–1904). Ultra-performance liquid chromatography-photodiode array detection (UPLC-PDA) and tandem mass spectrometry (MS/MS) analysis were used to quantify the cyanotoxins in seven cyanobacterial mat samples. MCNs were identified in six of the mat samples at concentrations from 0.5 to 16.1 µg?g–1 dry weight. BMAA was found in one sample (528 ng?g–1 dry weight, total BMAA), as well as two BMAA isomers, 2,4-diaminobutyric acid (DAB) and N-(2-aminoethyl) glycine (AEG) in six samples up to 6.56 and 6.79 μg?g–1 dry weight, respectively. No anatoxin-a was detected. The findings confirm that MCNs, BMAA and BMAA isomers are preserved under dry herbarium conditions. The ‘Discovery’ cyanobacterial mat samples represent the oldest polar cyanobacterial samples found to contain cyanotoxins to date and provide new baseline data for cyanotoxins in Antarctic freshwater cyanobacterial mats from prior to human activity in Antarctica, the development of the ozone hole and current levels of climatic change. 相似文献
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A journey through time: exploring temporal patterns amongst digitized plant specimens from Australia
MD. Mohasinul Haque David A. Nipperess John B. Baumgartner Linda J. Beaumont 《分类学与生物多样性》2018,16(6):604-613
Online access to species occurrence records has opened new windows into investigating biodiversity patterns across multiple scales. The value of these records for research depends on their spatial, temporal, and taxonomic quality. We assessed temporal patterns in records from the Australasian Virtual Herbarium, asking: (1) How temporally consistent has collecting been across Australia? (2) Which areas of Australia have the most reliable records, in terms of temporal consistency and inventory completeness? (3) Are there temporal trends in the completeness of attribute information associated with records? We undertook a multi-step filtering procedure, then estimated temporal consistency and inventory completeness for sampling units (SUs) of 50?km ×?50?km. We found temporal bias in collecting, with 80% of records collected over the period 1970–1999. South-eastern Australia, the Wet Tropics in north-east Queensland, and parts of Western Australia have received the most consistent sampling effort over time, whereas much of central Australia has had low temporal consistency. Of the SUs, 18% have relatively complete inventories with high temporal consistency in sampling. We also determined that 25% of digitized records had missing attribute information. By identifying areas with low reliability, we can limit erroneous inferences about distribution patterns and identify priority areas for future sampling. 相似文献