112 resultados para United States. Action. Inspector General Division.
em Aquatic Commons
Resumo:
Observations on maturation stages of nineteen species of economically important finfish off the Northeast coast of the USA were analyzed to examine relationships between fish size or age, and maturity. Maturation schedules and median lengths (L50) and ages (A50) at maturation were derived by fitting the logistic model to the observed proportions. Analyses were generally restricted to observations from 1985 to 1990 obtained during stratified random bottom trawl surveys conducted in spring and autumn by the Northeast Fisheries Science Center and the Commonwealth of Massachusetts Division of Marine Fisheries in waters of the continental shelf from Nova Scotia to Cape Hatteras, North Carolina. Butterfish, Peprilus triacanthus, attained sexual maturity at the smallest median length (11.4 cm, males) and pollock, Pollachius virens, at the highest (41.8 em, males). Median length at maturity for gadiforms ranged from 22.2 to 41.8 em. Within the pleuronectiforms, median length at maturity ranged from 19.1 to 30.4 cm. Median lengths for the pelagic and miscellaneous demersal species were in the same ranges as the pleuronectiforms. Butterfish also attained sexual maturity at the youngest median age (0.9 yr, both sexes) whereas redfish, Sebastes fasciatus, were the latest to mature (5.5 yr, both sexes). For gadids, the median age at maturity ranged from 1.3 to 2.3 yr. Within the pleuronectiforms, median age at maturity ranged from 1.3 to 4.4 yr and, for pelagic species, from 0.9 to 3.0 yr. Median lengths and ages for many species are lower than those reported in earlier studies of the same general region of the Northwest Atlantic. (PDF file contains 72 pages.)
Resumo:
Executive Summary: For over three decades, scientists have been documenting the decline of coral reef ecosystems, amid increasing recognition of their value in supporting high biological diversity and their many benefits to human society. Coral reef ecosystems are recognized for their benefits on many levels, such as supporting economies by nurturing fisheries and providing for recreational and tourism opportunities, providing substances useful for medical purposes, performing essential ecosystem services that protect against coastal erosion, and provid-ing a diversity of other, more intangible contributions to many cultures. In the past decade, the increased awareness regarding coral reefs has prompted action by governmental and non-governmental organizations, including increased funding from the U.S. Congress for conservation of these important ecosystems and creation of the U.S. Coral Reef Task Force (USCRTF) to coordinate activities and implement conservation measures [Presidential Executive Order 13089]. Numerous partnerships forged among Federal agencies and state, local, non-governmental, academic and private partners support activities that range from basic science to systematic monitoring of ecosystem com-ponents and are conducted by government agencies, non-governmental organizations, universities, and the private sector. This report shares the results of many of these efforts in the framework of a broad assessment of the condition of coral reef ecosystems across 14 U.S. jurisdictions and Pacific Freely Associated States. This report relies heavily on quantitative, spatially-explicit data that has been collected in the recent past and comparisons with historical data, where possible. The success of this effort can be attributed to the dedication of over 160 report contributors who comprised the expert writing teams for each jurisdiction. The content of the report chapters are the result of their considerable collaborative efforts. The writing teams, which were organized by jurisdiction and comprised of experts from numerous research and management institutions, were provided a basic chapter outline and a length limit, but the content of each chapter was left entirely to their discretion. Each jurisdictional chapter in the report is structured to: 1) describe how each of the primary threats identified in the National Coral Reef Action Strategy (NCRAS) has manifested in the jurisdiction; 2) introduce ongoing monitoring and assessment activities relative to three major categories of inquiry – water quality, benthic habitats, and associated biological communities – and provide summary results in a data-rich format; and 3) highlight recent management activities that promote conservation of coral reef ecosystems.
Resumo:
One goal of Gray’s Reef National Marine Sanctuary (NMS) is to protect the unique community found within the Sanctuary’s boundaries. An understanding of the ecological interactions, including trophic structure, among these organisms is necessary to realize this goal. Therefore, diet information for 184 fish species was summarized from 113 published studies. Among the fish included are 84 fish species currently known to reside in Gray’s Reef NMS. The locations of these studies ranged from the Atlantic Ocean off the coast of the northeast United States to northern Brazil, the Gulf of Mexico, and the Caribbean. All of the species described in this bibliography occur in the southeast United States and are, therefore, current or potential residents of Gray’s Reef National Marine Sanctuary. Each entry includes the objectives, brief methods, and conclusions of the article. The bibliography is also indexed by species. (PDF contains 64 pages.)
Resumo:
From the mid-1950's to the mid-1960's a series of quantitative surveys of the macrobenthic invertebrate fauna were conducted in the offshore New England region (Maine to Long Island, New York). The surveys were designed to 1) obtain measures of macrobenthic standing crop expressed in terms of density and biomass; 2) determine the taxonomic composition of the fauna (ca. 567 species); 3) map the general features of macrobenthic distribution; and 4) evaluate the fauna's relationships to water depth, bottom type, temperature range, and sediment organic carbon content. A total of 1,076 samples, ranging from 3 to 3,974 m in depth, were obtained and analyzed. The aggregate macrobenthic fauna consists of 44 major taxonomic groups (phyla, classes, orders). A striking fact is that only five of those groups (belonging to four phyla) account for over 80% of both total biomass and number of individuals of the macrobenthos. The five dominant groups are Bivalvia, Annelida, Amphipoda, Echninoidea, and Holothuroidea. Other salient features pertaining to the macrobenthos of the region are the following: substantial differences in quantity exist among different geographic subareas within the region, but with a general trend that both density and biomass increase from northeast to southwest; both density and biomass decrease with increasing depth; the composition of the bottom sediments significantly influences both the kind and quantity of macrobenthic invertebrates, the largest quantities of both measures of abundance occurring in the coarser grained sediments and diminishing with decreasing particle size; areas with marked seasonal changes in water temperature support an abundant and diverse fauna, whereas a uniform temperature regime is associated with a sparse, less diverse fauna; and no detectable trends are evident in the quantitative composition of the macrobenthos in relation to sediment organic carbon content. (PDF file contains 246 pages.)
Resumo:
This manual treats the six species of dicyemid mesozoans that have been reported in three species of hosts (Octopus vulgaris, O. joubini, and O. briareus) from the eastern coast of North America and the Gulf of Mexico, including the Florida Keys. All are parasites of species of Octopus and are in the genus Dicyema, family Dicyemidae. In the introduction, the life cycle, as known, and the general morphology of dicyemids are briefly described, and methods are given for collecting and preparing material for study. These are followed by a key to species and by an annotated checklist, which includes data, some hitherto unpublished, on their known prevalence in hosts from various localities including Bimini and Bermuda.(PDF file contains 20 pages.)
Resumo:
Forty-nine species of erect Bryozoa from a broad range of Cyclostome, Ctenostome, and Cheilostome families are described and illustrated, and an artificial dichotomous key is provided for their identification. In general, the marine bryozoan faunas of the northeastern coasts of the United States are poorly known; species records are sparse and voucher collections few, and it is certain that many more species occur in this region than are presently known. The species described here occur in intertidal, coastal or offshore habitats; some are well known and have been recorded on numerous previous occasions, others have been only rarely reported, while a few are known to occur commonly in the north of the region but have yet to be recorded south of Cape Cod. Some of the species described have not been recorded at all on northeastern coasts of the United States, but are widely distributed in North Atlantic continental shelf habitats and perhaps occur in similar parts of the outer shelf of this region. This fauna is thus provisional, but is intended to stimulate further work on the Bryozoa. (PDF file contains 52 pages.)
Resumo:
This manual includes an introduction to the general biology, a selected bibliography, and an illustrated key to 11 genera and 17 species of copepods of the Crustacea, Subclass Copepoda, Order Cyclopoida, Families Archinotodelphyidae, Notodelphyidae and Ascidicolidae, associated with ascidians from the Atlantic Coast of the United States. Species distributed from the Gulf of Maine to Long Island Sound are emphasized. An annotated systematic list, with statements of the world distribution and new records of association with hosts, and a systematic index are also provided. (PDF file contains 44 pages.)
Resumo:
The biography of Charles Bradford Hudson that follows this preface had its seeds about 1965 when I (VGS) was casually examining the extensive files of original illustrations of fishes stored in the Division of Fishes, National Museum of Natural History, Smithsonian Institution. I happened upon the unpublished illustration of a rainbow trout by Hudson and was greatly impressed with its quality. The thought occurred to me then that the artist must have gone on to do more than just illustrate fishes. During the next 20 years I occasionally pawed through those files, which contained the work of numerous artists, who had worked from 1838 to the present. In 1985, I happened to discuss the files with my supervisor, who urged me to produce a museum exhibit of original fish illustrations. This I did, selecting 200 of the illustrations representing 21 artists, including, of course, Hudson. As part of the text for the exhibit, Drawn from the Sea, Art in the Service of Ichthyology, I prepared short biographies of each of the artists. The exhibit, with an available poster, was shown in the Museum for six months, and a reduced version was exhibited in U.S. and Canadian museums during the next 3 years.
Resumo:
ABSTRACT—Bycatch mortality of Pacific halibut, Hippoglossus stenolepis, in nontarget fisheries is composed primarily of immature fish, and substantial reductions in yield to directed halibut fisheries result from this bycatch. Distant-water bottomtrawl fleets operating off the North American coast, beginning in the mid 1960’s, experienced bycatch mortality of over 12,000 t annually. Substantial progress on reducing this bycatch was not achieved until the of extension fisheries jurisdictions by the United States and Canada in 1977. Bycatch began to increase again during the expansion of domestic catching capacity for groundfish, and by the early 1990’s it had returned to levels seen during the period of foreign fishing. Collaborative action by Canada and the United States through the International Pacific Halibut Commission has resulted in substantial reductions in bycatch mortality in some areas. Methods of control have operated at global, fleet, and individual vessel levels. We evaluate the hierarchy of effectiveness for these control measures and identify regulatory needs for optimum effects. New monitoring technologies offer the promise of more cost-effective approaches to bycatch reduction.
Resumo:
EXTRACT (SEE PDF FOR FULL ABSTRACT): Four broad regions of the western United States within which annual streamflows exhibit strong spatial coherence are identified using principal component analysis with a varimax rotation. Geographically, the four regions encompass the Pacific Northwest, Far West-Great Basin, Central Rockies-High Plains, and Northern Great Plains. These regions are really consistent with previously documented, descriptively derived streamflow regimes as well as with general atmospheric circulation and precipitation modes of variation. Collectively, the four regional components account for nearly 63 percent of the total annual variation in western U.S. streamflow. The time history of most principal component patterns exhibit little or no persistence.
Resumo:
The ecological integrity of coral reef ecosystems in the U.S. Caribbean is widely considered to have deteriorated in the last three decades due to a range of threats and stressors from both human and non-human processes Rothenberger 2008, Wilkinson 2008). In response to the threats to Caribbean coral reef ecosystems and other regions around the world, the United States Government authorized the Coral Reef Conservation Act of 2000 to: (1) preserve, sustain, and restore the condition of coral reef ecosystems; (2) promote the wise management and sustainable use of coral reef ecosystems to benefit local communities and the Nation; and (3) develop sound scientific information on the condition of coral reef ecosystems and the threats to such ecosystems. The Act also resulted in the formation of a National Coral Reef Action Strategy and a Coral Reef Conservation Program. The Action Strategy (Goal 2 of Action Theme 1) outlined the importance of monitoring and assessing coral reef health as a mechanism toward reducing many threats to these ecosystems. Monitoring was considered of high importance in addressing impacts from climate change; disease; overfishing; destructive fishing practices; habitat destruction; invasive species; coastal development; coastal pollution; sedimentation/runoff and overuse from tourism. The strategy states that successful coral reef ecosystem conservation requires adaptive management that responds quickly to changing environmental conditions. This, in turn, depends on monitoring programs that track trends in coral reef ecosystem health and reveal patterns in their condition before irreparable harm occurs. As such, monitoring plays a vital role in guiding and supporting the establishment of complex or potentially controversial management strategies such as no-take ecological reserves, fishing gear restrictions, or habitat restoration, by documenting the impacts of gaps in existing management schemes and illustrating the effectiveness of new measures over time. Long-term monitoring is also required to determine the effectiveness of various management strategies to conserve and enhance coral reef ecosystems.
Resumo:
In the past decade, increased awareness regarding the declining condition of U.S. coral reefs has prompted various actions by governmental and non-governmental organizations. Presidential Executive Order 13089 created the U.S. Coral Reef Task Force (USCRTF) in 1998 to coordinate federal and state/territorial activities (Clinton, 1998), and the Coral Reef Conservation Act of 2000 provided Congressional funding for activities to conserve these important ecosystems, including mapping, monitoring and assessment projects carried out through the support of NOAA’s CRCP. Numerous collaborations forged among federal agencies and state, local, non-governmental, academic and private partners now support a variety of monitoring activities. This report shares the results of many of these monitoring activities, relying heavily on quantitative, spatially-explicit data that has been collected in the recent past and comparisons with historical data where possible. The success of this effort can be attributed to the dedication of over 270 report contributors who comprised the expert writing teams in the jurisdictions and contributed to the National Level Activities and National Summary chapters. The scope and content of this report are the result of their dedication to this considerable collaborative effort. Ultimately, the goal of this report is to answer the difficult but vital question: what is the condition of U.S. coral reef ecosystems? The report attempts to base a response on the best available science emerging from coral reef ecosystem monitoring programs in 15 jurisdictions across the country. However, few monitoring programs have been in place for longer than a decade, and many have been initiated only within the past two to five years. A few jurisdictions are just beginning to implement monitoring programs and face challenges stemming from a lack of basic habitat maps and other ecosystem data in addition to adequate training, capacity building, and technical support. There is also a general paucity of historical data describing the condition of ecosystem resources before major human impacts occurred, which limits any attempt to present the current conditions within an historical context and contributes to the phenomenon of shifting baselines (Jackson, 1997; Jackson et al., 2001; Pandolfi et al., 2005).
Resumo:
General Circulation Models (GCMs) may be useful in estimating the ecological impacts of global climatic change. We analyzed seasonal weather patterns over the conterminous United States and determined that regional patterns of rainfall seasonality appear to control the distributions of the Nation's major biomes. These regional patterns were compared to the output from three GCMs for validation. The models appear to simulate the appropriate seasonal climates in the northern tier of states. However, the spatial extent of these regions is distorted. None of the models accurately portrayed rainfall seasonalities in the southern tier of states, where biomes are primarily influenced by the Bermuda High.
Resumo:
EXTRACT (SEE PDF FOR FULL ABSTRACT): A local climate model (LCM) has been developed to simulate the modern and 18 ka climate of the southwestern United States. ... LCM solutions indicate summers were about 1°C cooler and winters 11°C cooler at 18 ka. Annual PREC increased 68% at 18 ka, with large increases in spring and fall PREC and diminished summer monsoonal PREC. ... Validation of simulations of 18 ka climate indicate general agreement with proxy estimates of climate for that time. However, the LCM estimates of summer temperatures are about 5 to 10°C higher than estimates from proxy reconstructions.
Resumo:
Wintertime precipitation in the mountains of the western United States during a warm or cool period has a pronounced influence on streamflow. During a warm year, streamflow at intermediate elevations responds more immediately to precipitation events; during a cold year, much of the discharge is delayed until the snow melts in spring and summer. Previous efforts at studying these extremes have been hampered by a limited number and length of observational analyses. In this study, we augment this limited observational record by analyzing a simplified general circulation model.