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- Acoustic survey (1)
- Balaenoptera musculus (1)
- Blue whale (1)
- Covariates (1)
- Density changes (1)
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- Density dependence (1)
- Diporeia (1)
- Encounter rate (1)
- Feeding ground (1)
- Generalized linear models (1)
- Georgian Bay (1)
- Harbor seals (1)
- Iteratively weighted least squares (1)
- North Channel (1)
- Overdispersion (1)
- Polynuclear aromatic hydrocarbons (1)
- Population (1)
- Quasi models (1)
- Salmon (1)
- Toxicity (1)
- Visual survey (1)
- Zoobenthos (1)
Articles 1 - 26 of 26
Full-Text Articles in Physical Sciences and Mathematics
Western Gray Whales Off Sakhalin Island, Russia: A Joint Russia-U.S. Scientific Investigation July-September 2007, David W. Weller, Amanda L. Bradford, Aimée R. Lang, Hyun Woo Kim, Maxim Sidorenko, Grigory A. Tsidulko, Alexander M. Burdin, Robert L. Brownell Jr.
Western Gray Whales Off Sakhalin Island, Russia: A Joint Russia-U.S. Scientific Investigation July-September 2007, David W. Weller, Amanda L. Bradford, Aimée R. Lang, Hyun Woo Kim, Maxim Sidorenko, Grigory A. Tsidulko, Alexander M. Burdin, Robert L. Brownell Jr.
United States Department of Commerce: Staff Publications
A collaborative Russia-U.S. research program on western gray whales (Eschrichtius robustus) summering off northeastern Sakhalin Island, Russia, has been ongoing since 1995 and has produced important new information on the present day conservation status of this critically endangered population. This interim report reviews preliminary findings from 2007 research activities and combines such with data from previous years, in some cases ranging back to 1994. Photo-identification research conducted off Sakhalin Island in 2007 resulted in the identification of 83 whales, including nine calves and two previously unidentified non-calves. When combined with data from 1994-2006, a catalog of 169 photo-identified …
Arctic Report Card 2007: Tracking Recent Environmental Changes, J. Overland, L. Bengtsson, R. Przybylak, J. Walsh, J. Richter-Menge, S. Nghiem, D. Perovich, I. Rigor, A. Proshutinsky, J. Morison, V. Romanovsky, R. Armstrong, L.D. Hinzman, N. Oberman, A. Shiklomanov, E. Hanna, J. Box, P. Huybrechts, R. Van Bogaert, D. Walker, G.J. Jia, O. Grau, M. Hallinger, M. De Dapper, C. Jonasson, T.V. Callaghan, D. Russell, M.J.J.E. Loonen, C. Zöckler, B. Ebbinge
Arctic Report Card 2007: Tracking Recent Environmental Changes, J. Overland, L. Bengtsson, R. Przybylak, J. Walsh, J. Richter-Menge, S. Nghiem, D. Perovich, I. Rigor, A. Proshutinsky, J. Morison, V. Romanovsky, R. Armstrong, L.D. Hinzman, N. Oberman, A. Shiklomanov, E. Hanna, J. Box, P. Huybrechts, R. Van Bogaert, D. Walker, G.J. Jia, O. Grau, M. Hallinger, M. De Dapper, C. Jonasson, T.V. Callaghan, D. Russell, M.J.J.E. Loonen, C. Zöckler, B. Ebbinge
United States Department of Commerce: Staff Publications
Collectively, the observations indicate that the overall warming of the Arctic system continued in 2007. There are some elements that are stabilizing or returning to climatological norms. These mixed tendencies illustrate the sensitivity and complexity of the Arctic System.
Atmosphere: Hot spot shifts toward Europe
Ocean: North Pole Temperatures at depth returning to 1990s values
Sea Ice: Summer extent at record minimum
Greenland: Recent warm temperatures associated with net ice loss
Biology: increasing tundra shrub cover and variable treeline advance; up to 80% declines in some caribou herds while goose populations double
Land: Increase in permafrost temperatures
The Arctic Report …
Scientific Reports Of Soviet Whaling Expeditions In The North Pacific, 1955-1978, Y. V. Ivashchenko, P. J. Clapham, R. L. Brownell Jr.
Scientific Reports Of Soviet Whaling Expeditions In The North Pacific, 1955-1978, Y. V. Ivashchenko, P. J. Clapham, R. L. Brownell Jr.
United States Department of Commerce: Staff Publications
The translated and annotated materials in this volume constitute a collection of 18 formerly secret internal reports written by Soviet scientists working aboard whaling factory ships in the North Pacific. The reports cover the period from 1955 to 1978. During most of this time, the USSR was engaged in a massive campaign of illegal whaling worldwide; these illegal catches continued until introduction of the International Whaling Commission’s International Observer Scheme in 1972. The reports were copied from the archives of the Pacific Research and Fisheries Center (TINRO) in Vladivostok by Alfred A. Berzin, the former director of TINRO’s marine mammal …
Population Assessment Of Western Gray Whales In 2007, Justin G. Cooke, David W. Weller, Amanda L. Bradford, Alexander M. Burdin, Robert L. Brownell Jr.
Population Assessment Of Western Gray Whales In 2007, Justin G. Cooke, David W. Weller, Amanda L. Bradford, Alexander M. Burdin, Robert L. Brownell Jr.
United States Department of Commerce: Staff Publications
A population assessment of the western gray whale (Eschrichtius robustus) was conducted using photo-identification data collected off Sakhalin Island under the joint Russia-U.S. program from 1994 to 2006. This is an update of the assessments by Reeves et al (2005) and Cooke et al. (2006) which used data up to 2003 and 2005 respectively, fitted to the same, individually-based population model. New median estimates of key population parameters (with 90% Bayesian confidence intervals) are 0.982 (0.972 - 0.991) for the noncalf annual survival rate; 0.76 (0.66 - 0.85) for the survival rate from calf to yearling; 2.9% per …
Status Of Blue Whales Off Isla De Chiloe, Chile, During 2007 Field Season, Bárbara Galletti Vernazzani, Carole A. Carlson, Elsa Cabrera, Robert L. Brownell Jr.
Status Of Blue Whales Off Isla De Chiloe, Chile, During 2007 Field Season, Bárbara Galletti Vernazzani, Carole A. Carlson, Elsa Cabrera, Robert L. Brownell Jr.
United States Department of Commerce: Staff Publications
Since 2004, a collaborative research program of the Alfaguara Project on blue whales off Isla de Chiloe, Chile, has produce important new information on present day conservation status of this population. This paper presents preliminary findings from 2007 and compares such data with that reported in previous years. Land-based monitoring in 2007 resulted in 36 days of observations with 262.85 h of land-based effort. The maximum number of individuals sighted from land ranged from 2 to 44, with an average of 18.14 individuals per day (SD=12.00 ; CI95% =14.08 - 22.20). Preliminary results on fifteen of seventeen photo-identification surveys conducted …
Proposed Updates To The List Of Recognised Species Of Cetaceans, W. F. Perrin, Robert L. Brownell Jr.
Proposed Updates To The List Of Recognised Species Of Cetaceans, W. F. Perrin, Robert L. Brownell Jr.
United States Department of Commerce: Staff Publications
Addition of three species to the list is recommended based on recent literature. (Orcaella brevirostris) has been split into the Irrawaddy dolphin (O. brevirostris) and the Australian snubfin dolphin (O. heinsohni). Sotalia fluviatilis has been split into the riverine tucuxi (S. fluviatilis) and the marine "costero" (S. guianensis). Evidence to support both of these splits is convincing, and we recommend that they be recognized in the list. The existence of the Bryde's-whale-like species described in 2003 as Balaenoptera omurai has been confirmed with additional genetic (nuclear) data. While the species …
State Of The Climate In 2006 Executive Summary, A. Arguez, A.M. Waple, A.M. Sanchez-Lugo
State Of The Climate In 2006 Executive Summary, A. Arguez, A.M. Waple, A.M. Sanchez-Lugo
United States Department of Commerce: Staff Publications
On the heels of 2005’s record-breaking weather events, 2006 was also a year of records. This was especially the case over the polar regions, where the largest Antarctic ozone hole on record occurred in 2006. Sea ice extent in the Antarctic reached records at times for both maximum and minimum extent, and in the Arctic, scientists observed the second smallest sea ice extent on record (behind 2005). These record events came as attention to the polar regions gained greater focus, thanks in large part to the International Polar Year, during which an unprecedented effort is underway to monitor the Arctic …
Skin Lesions On Blue Whales Off Southern Chile: Possible Conservation Implications?, Robert L. Brownell Jr., Carole A. Carlson, Barbara Galletti Vernazzani, Elsa Cabrera
Skin Lesions On Blue Whales Off Southern Chile: Possible Conservation Implications?, Robert L. Brownell Jr., Carole A. Carlson, Barbara Galletti Vernazzani, Elsa Cabrera
United States Department of Commerce: Staff Publications
We report on three types of skin lesions in a population of blue whales, Balaenoptera musculus, off the northwestern coast of Isla Grande de Chiloe, Chile. These lesions were: (1) cookie-cutter shark, Isistius brasilensis, bites, (2) vesicular or blister lesions, and (3) a tattoo-like skin disease. The presence of these lesions was determined by the examining photos collected in 2006 and 2007 for a blue whale photo-identification project. We examined 289 photographs of 68 individuals for lesions. The cookie-cutter shark lesions are common on these blue whales and similar to those reported from other species of cetaceans. Skin …
“A Doubt Is At Best An Unsafe Standard”: Measuring Sugar In The Early Bureau Of Standards, David Singerman
“A Doubt Is At Best An Unsafe Standard”: Measuring Sugar In The Early Bureau Of Standards, David Singerman
United States Department of Commerce: Staff Publications
In 1900, measuring the purity of sugar was a problem with serious economic consequences, and Congress created the Bureau of Standards in part to create accurate standards for saccharimetry. To direct the Polarimetry Section, Director Stratton hired the young chemist Frederick Bates, who went on to make significant contributions to the discipline of sugar chemistry. This paper explores four of Bates’s greatest accomplishments: identifying the error caused by clarifying lead acetate, inventing the remarkable quartz-compensating saccharimeter with adjustable sensibility, discovering the significant error in the prevailing Ventzke saccharimetric scale, and reviving the International Commission for Uniform Methods of Sugar Analysis …
Estimating The Number Of Whales Entering Trade Using Dna Profiling And Capture-Recapture Analysis Of Market Products, C. Scott Baker, Justin G. Cooke, Shane Lavery, Merel L. Dalebout, Robert L. Brownell Jr., Yong-Un Ma, Naoko Funahashi, Colm Carraher
Estimating The Number Of Whales Entering Trade Using Dna Profiling And Capture-Recapture Analysis Of Market Products, C. Scott Baker, Justin G. Cooke, Shane Lavery, Merel L. Dalebout, Robert L. Brownell Jr., Yong-Un Ma, Naoko Funahashi, Colm Carraher
United States Department of Commerce: Staff Publications
Surveys of commercial markets combined with molecular taxonomy (i.e. molecular monitoring) provide a means to detect products from illegal, unregulated and/or unreported (IUU) exploitation, including the sale of fisheries bycatch and wild meat (bushmeat). Capture-recapture analyses of market products using DNA profiling have the potential to estimate the total number of individuals entering the market. However, these analyses are not directly analogous to those of living individuals because a ‘market individual’ does not die suddenly but, instead, remains available for a time in decreasing quantities, rather like the exponential decay of a radioactive isotope. Here we use mitochondrial DNA (mtDNA) …
Past And Present Distribution, Densities And Movements Of Blue Whales Balaenoptera Musculus In The Southern Hemisphere And Northern Indian Ocean, T. A. Branch, K. M. Stafford, D. M. Palacios, C. Allison, J. L. Bannister, C. L. K. Burton, E. Cabrera, C. A. Carlson, B. Galletti Vernazzani, P. C. Gill, R. Hucke-Gaete, K. C. S. Jenner, M.-N. M. Jenner, K. Matsuoka, Y. A. Mikhalev, T. Miyashita, M. G. Morrice, S. Nishiwaki, V. J. Sturrock, D. Tormosov, R. C. Anderson, A. N. Baker, P. B. Best, P. Borsa, R. L. Brownell Jr., S. Childerhouse, K. P. Findlay, T. Gerrodette, A. D. Ilangakoon, M. Joergensen, B. Kahn, D. K. Ljungblad, B. Maughan, R. D. Mccauley, S. Mckay, T. F. Norris, Oman Whale, Dolphin Research Group, R. M. Warneke, S. Rankin, F. Samaran, D. Thiele, K. Van Waerebeek
Past And Present Distribution, Densities And Movements Of Blue Whales Balaenoptera Musculus In The Southern Hemisphere And Northern Indian Ocean, T. A. Branch, K. M. Stafford, D. M. Palacios, C. Allison, J. L. Bannister, C. L. K. Burton, E. Cabrera, C. A. Carlson, B. Galletti Vernazzani, P. C. Gill, R. Hucke-Gaete, K. C. S. Jenner, M.-N. M. Jenner, K. Matsuoka, Y. A. Mikhalev, T. Miyashita, M. G. Morrice, S. Nishiwaki, V. J. Sturrock, D. Tormosov, R. C. Anderson, A. N. Baker, P. B. Best, P. Borsa, R. L. Brownell Jr., S. Childerhouse, K. P. Findlay, T. Gerrodette, A. D. Ilangakoon, M. Joergensen, B. Kahn, D. K. Ljungblad, B. Maughan, R. D. Mccauley, S. Mckay, T. F. Norris, Oman Whale, Dolphin Research Group, R. M. Warneke, S. Rankin, F. Samaran, D. Thiele, K. Van Waerebeek
United States Department of Commerce: Staff Publications
1. Blue whale locations in the Southern Hemisphere and northern Indian Ocean were obtained from catches (303 239), sightings (4383 records of ≥ 8058 whales), strandings (103), Discovery marks (2191) and recoveries (95), and acoustic recordings.
2. Sighting surveys included 7 480 450 km of effort plus 14 676 days with unmeasured effort. Groups usually consisted of solitary whales (65.2%) or pairs (24.6%); larger feeding aggregations of unassociated individuals were only rarely observed. Sighting rates (groups per 1000 km from many platform types) varied by four orders of magnitude and were lowest in the waters of Brazil, South Africa, the …
Use Of Chemical Tracers In Assessing The Diet And Foraging Regions Of Eastern North Pacific Killer Whales, Margaret M. Krahn, David P. Herman, Craig O. Matkin, John W. Durban, Lance Barrett-Lennard, Douglas G. Burrows, Marilyn E. Dahlheim, Nancy Black, Richard G. Leduc, Paul R. Wade
Use Of Chemical Tracers In Assessing The Diet And Foraging Regions Of Eastern North Pacific Killer Whales, Margaret M. Krahn, David P. Herman, Craig O. Matkin, John W. Durban, Lance Barrett-Lennard, Douglas G. Burrows, Marilyn E. Dahlheim, Nancy Black, Richard G. Leduc, Paul R. Wade
United States Department of Commerce: Staff Publications
Top predators in the marine environment integrate chemical signals acquired from their prey that reflect both the species consumed and the regions from which the prey were taken. These chemical tracers—stable isotope ratios of carbon and nitrogen; persistent organic pollutant (POP) concentrations, patterns and ratios; and fatty acid profiles—were measured in blubber biopsy samples from North Pacific killer whales (Orcinus orca) (n = 84) and were used to provide further insight into their diet, particularly for the offshore group, about which little dietary information is available. The offshore killer whales were shown to consume prey species that were …
Use Of Chemical Tracers In Assessing The Diet And Foraging Regions Of Eastern North Pacific Killer Whales, Margaret M. Krahn, David P. Herman, Craig O. Matkin, John W. Durban, Lance Barrett-Lennard, Douglas G. Burrows, Marilyn E. Dahlheim, Nancy Black, Richard G. Leduc, Paul R. Wade
Use Of Chemical Tracers In Assessing The Diet And Foraging Regions Of Eastern North Pacific Killer Whales, Margaret M. Krahn, David P. Herman, Craig O. Matkin, John W. Durban, Lance Barrett-Lennard, Douglas G. Burrows, Marilyn E. Dahlheim, Nancy Black, Richard G. Leduc, Paul R. Wade
United States Department of Commerce: Staff Publications
Top predators in the marine environment integrate chemical signals acquired from their prey that reflect both the species consumed and the regions from which the prey were taken. These chemical tracers—stable isotope ratios of carbon and nitrogen; persistent organic pollutant (POP) concentrations, patterns and ratios; and fatty acid profiles—were measured in blubber biopsy samples from North Pacific killer whales (Orcinus orca) (n = 84) and were used to provide further insight into their diet, particularly for the offshore group, about which little dietary information is available. The offshore killer whales were shown to consume prey species that were …
Space–Time Zero-Inflated Count Models Of Harbor Seals, Jay M. Ver Hoef, John K. Jansen
Space–Time Zero-Inflated Count Models Of Harbor Seals, Jay M. Ver Hoef, John K. Jansen
United States Department of Commerce: Staff Publications
Environmental data are spatial, temporal, and often come with many zeros. In this paper, we included space–time random effects in zero-inflated Poisson (ZIP) and ‘hurdle’ models to investigate haulout patterns of harbor seals on glacial ice. The data consisted of counts, for 18 dates on a lattice grid of samples, of harbor seals hauled out on glacial ice in Disenchantment Bay, near Yakutat, Alaska. A hurdle model is similar to a ZIP model except it does not mix zeros from the binary and count processes. Both models can be used for zero-inflated data, and we compared space–time ZIP and hurdle …
Characterization Of Eight Microsatellite Loci In Steller Sea Lions (Eumetopias Jubatus), Ryan M. Huebinger, Edward E. Louis Jr., Thomas Gelatt, Lorrie D. Rea, John W. Bickham
Characterization Of Eight Microsatellite Loci In Steller Sea Lions (Eumetopias Jubatus), Ryan M. Huebinger, Edward E. Louis Jr., Thomas Gelatt, Lorrie D. Rea, John W. Bickham
United States Department of Commerce: Staff Publications
Steller sea lions (Eumetopias jubatus) are listed as an endangered species in western Alaska and have exhibited a significant population decline throughout their range. Eight microsatellite loci were isolated from genomic DNA libraries. In addition, all these markers were found to be variable in nine individuals of the California sea lion (Zalophus californicus). This panel of markers was developed to analyze population structure in Steller sea lions throughout their range.
Provisioning Strategies Of Antarctic Fur Seals And Chinstrap Penguins Produce Different Responses To Distribution Of Common Prey And Habitat, Taro Ichii, John Bengston, Peter Boveng, Yoshimi Takao, John Jansen, Lisa Hiruki-Raring, Michael Cameron, Hiroshi Okamura, Tomonari Hayashi, Mikio Naganobu
Provisioning Strategies Of Antarctic Fur Seals And Chinstrap Penguins Produce Different Responses To Distribution Of Common Prey And Habitat, Taro Ichii, John Bengston, Peter Boveng, Yoshimi Takao, John Jansen, Lisa Hiruki-Raring, Michael Cameron, Hiroshi Okamura, Tomonari Hayashi, Mikio Naganobu
United States Department of Commerce: Staff Publications
Central-place foragers that must return to a breeding site to deliver food to offspring are faced with trade-offs between prey patch quality and distance from the colony. Among colonial animals, pinnipeds and seabirds may have different provisioning strategies, due to differences in their ability to travel and store energy. We compared the foraging areas of lactating Antarctic fur seals and chinstrap penguins breeding at Seal Island, Antarctica, to investigate whether they responded differently to the distribution of their prey (Antarctic krill and myctophid fish) and spatial heterogeneity in their habitat. Dense krill concentrations occurred in the shelf region near the …
Estimating Abundance Of Killer Whales In The Nearshore Waters Of The Gulf Of Alaska And Aleutian Islands Using Line-Transect Sampling, Alexandre N. Zerbini, Janice M. Waite, John W. Durban, Rick Leduc, Marilyn E. Dahlheim, Paul R. Wade
Estimating Abundance Of Killer Whales In The Nearshore Waters Of The Gulf Of Alaska And Aleutian Islands Using Line-Transect Sampling, Alexandre N. Zerbini, Janice M. Waite, John W. Durban, Rick Leduc, Marilyn E. Dahlheim, Paul R. Wade
United States Department of Commerce: Staff Publications
Killer whale (Orcinus orca Linnaeus, 1758) abundance in the North Pacific is known only for a few populations for which extensive longitudinal data are available, with little quantitative data from more remote regions. Line-transect ship surveys were conducted in July and August of 2001–2003 in coastal waters of the western Gulf of Alaska and the Aleutian Islands. Conventional and Multiple Covariate Distance Sampling methods were used to estimate the abundance of different killer whale ecotypes, which were distinguished based upon morphological and genetic data. Abundance was calculated separately for two data sets that differed in the method by which …
Killer Whales And Marine Mammal Trends In The North Pacific—A Re-Examination Of Evidence For Sequential Megafauna Collapse And The Prey-Switching Hypothesis, Paul R. Wade, Vladimir N. Burkanov, Marilyn E. Dahlheim, Nancy A. Friday, Lowell W. Fritz, Thomas R. Loughlin, Sally A. Mizroch, Marcia M. Muto, Dale W. Rice, Lance G. Barrett-Leonard, Nancy Black, Alexander Burdin, John Calambokidis, Sal Cerchio, John K. B. Ford, Jeff Jacobsen, Craig Matkin, Dena Matkin, Amee Mehta, Robert Small, Janice Straley, Shannon Mccluskey, Glenn Vanblaricomm, P J. Clapham
Killer Whales And Marine Mammal Trends In The North Pacific—A Re-Examination Of Evidence For Sequential Megafauna Collapse And The Prey-Switching Hypothesis, Paul R. Wade, Vladimir N. Burkanov, Marilyn E. Dahlheim, Nancy A. Friday, Lowell W. Fritz, Thomas R. Loughlin, Sally A. Mizroch, Marcia M. Muto, Dale W. Rice, Lance G. Barrett-Leonard, Nancy Black, Alexander Burdin, John Calambokidis, Sal Cerchio, John K. B. Ford, Jeff Jacobsen, Craig Matkin, Dena Matkin, Amee Mehta, Robert Small, Janice Straley, Shannon Mccluskey, Glenn Vanblaricomm, P J. Clapham
United States Department of Commerce: Staff Publications
Springer et al. (2003) contend that sequential declines occurred in North Pacific populations of harbor and fur seals, Steller sea lions, and sea otters. They hypothesize that these were due to increased predation by killer whales, when industrial whaling’s removal of large whales as a supposed primary food source precipitated a prey switch. Using a regional approach, we reexamined whale catch data, killer whale predation observations, and the current biomass and trends of potential prey, and found little support for the prey-switching hypothesis. Large whale biomass in the Bering Sea did not decline as much as suggested by Springer et …
Long-Term Trends In Benthic Macroinvertebrate Populations In Lake Huron Over The Past Four Decades, Thomas F. Nalepa, David L. Fanslow, Steven A. Pothoven, Andrew J. Foley Iii, Gregory A. Lang
Long-Term Trends In Benthic Macroinvertebrate Populations In Lake Huron Over The Past Four Decades, Thomas F. Nalepa, David L. Fanslow, Steven A. Pothoven, Andrew J. Foley Iii, Gregory A. Lang
United States Department of Commerce: Staff Publications
Surveys of the benthic macroinvertebrate community were conducted in the main basin of Lake Huron in 2000 and 2003, and in Georgian Bay and North Channel in 2002. Results were compared to surveys conducted in the 1960s and early 1970s. Although data of earlier surveys were inconsistent, our best estimates suggest that total density of the four major benthic taxa (Diporeia spp., Oligochaeta, Sphaeriidae, and Chironomidae) in the main basin declined dramatically between the early 1970s and 2000. Populations of all major taxa continued to decline between 2000 and 2003, particularly Diporeia and Sphaeriidae. Diporeia was rare or absent …
Antler Size Of Alaskan Moose Alces Alces Gigas: Effects Of Population Density, Hunter Harvest And Use Of Guides, Jennifer I. Schmidt, Jay M. Ver Hoef, R. Terry Bowyer
Antler Size Of Alaskan Moose Alces Alces Gigas: Effects Of Population Density, Hunter Harvest And Use Of Guides, Jennifer I. Schmidt, Jay M. Ver Hoef, R. Terry Bowyer
United States Department of Commerce: Staff Publications
Moose Alces alces gigas in Alaska, USA, exhibit extreme sexual dimorphism, with adult males possessing large, elaborate antlers. Antler size and conformation are influenced by age, nutrition and genetics, and these bony structures serve to establish social rank and affect mating success. Population density, combined with anthropogenic effects such as harvest, is thought to influence antler size. Antler size increased as densities of moose decreased, ostensibly a density-dependent response related to enhanced nutrition at low densities. The vegetation type where moose were harvested also affected antler size, with the largest-antlered males occupying more open habitats. Hunts with guides occurred in …
Saving The Vaquita: Immediate Action, Not More Data, Armando Jaramillo-Legorreta, Lorenzo Rojas-Bracho, Robert L. Brownell Jr., Andrew J. Read, Randall R. Reeves, Katherine Ralls, Barbara L. Taylor
Saving The Vaquita: Immediate Action, Not More Data, Armando Jaramillo-Legorreta, Lorenzo Rojas-Bracho, Robert L. Brownell Jr., Andrew J. Read, Randall R. Reeves, Katherine Ralls, Barbara L. Taylor
United States Department of Commerce: Staff Publications
The recent likely extinction of the baiji (Chinese river dolphin [Lipotes vexillifer]) (Turvey et al. 2007) makes the vaquita (Gulf of California porpoise [Phocoena sinus]) the most endangered cetacean. The vaquita has the smallest range of any porpoise, dolphin, or whale and, like the baiji, has long been threatened primarily by accidental deaths in fishing gear (bycatch) (Rojas-Bracho et al. 2006). Despite repeated recommendations from scientific bodies and conservation organizations, no effective actions have been taken to remove nets from the vaquita’s environment. Here, we address three questions that are important to vaquita conservation: (1) How …
The Whaling Issue: Conservation, Confusion, And Casuistry, Phillip J. Clapham, Simon Childerhouse, Nicolas J. Gales, Lorenzo Rojas-Bracho, Michael F. Tillman, Robert L. Brownell Jr.
The Whaling Issue: Conservation, Confusion, And Casuistry, Phillip J. Clapham, Simon Childerhouse, Nicolas J. Gales, Lorenzo Rojas-Bracho, Michael F. Tillman, Robert L. Brownell Jr.
United States Department of Commerce: Staff Publications
Morishita’s “multiple analysis”of the whaling issue [Morishita J. Multiple analysis of the whaling issue: Understanding the dispute by a matrix. Marine Policy 2006;30:802–8] is essentially a restatement of the Government of Japan’s whaling policy, which confuses the issue through selective use of data, unsubstantiated facts, and the vilification of opposing perspectives. Here, we deconstruct the major problems with Morishita’s article and provide an alternative view of the whaling dispute. For many people in this debate, the issue is not that some whales are not abundant, but that the whaling industry cannot be trusted to regulate itself or to honestly assess …
Quasi-Poisson Vs. Negative Binomial Regression: How Should We Model Overdispersed Count Data?, Jay M. Ver Hoef, Peter L. Boveng
Quasi-Poisson Vs. Negative Binomial Regression: How Should We Model Overdispersed Count Data?, Jay M. Ver Hoef, Peter L. Boveng
United States Department of Commerce: Staff Publications
Quasi-Poisson and negative binomial regression models have equal numbers of parameters, and either could be used for overdispersed count data. While they often give similar results, there can be striking differences in estimating the effects of covariates. We explain when and why such differences occur. The variance of a quasi-Poisson model is a linear function of the mean while the variance of a negative binomial model is a quadratic function of the mean. These variance relationships affect the weights in the iteratively weighted least-squares algorithm of fitting models to data. Because the variance is a function of the mean, large …
Chronic Exposure To Polynuclear Aromatic Hydrocarbons In Natal Habitats Leads To Decreased Equilibrium Size, Growth, And Stability Of Pink Salmon Populations, Ron A. Heintz
United States Department of Commerce: Staff Publications
The immediate and delayed effects of embryonic exposure to low levels of polynuclear aromatic hydrocarbons (PAHs) have been shown to reduce survival to maturity by 50% in exposed pink salmon populations. This suggests that chronically exposed populations could be extirpated over relatively few generations, but the effect of density dependence on extirpation rate is unknown. This study examines the interaction of PAH effects and randomly varying density dependence on a simulated population. The simulation derives from 70 years of observations made on a single pink salmon population and toxicity studies involving a hatchery population in the same watershed. Results from …
Blue Whale Visual And Acoustic Encounter Rates In The Southern California Bight, Erin M. Oleson, John Calambokidis, Jay Barlow, John A. Hildebrand
Blue Whale Visual And Acoustic Encounter Rates In The Southern California Bight, Erin M. Oleson, John Calambokidis, Jay Barlow, John A. Hildebrand
United States Department of Commerce: Staff Publications
The relationship between blue whale (Balaenoptera musculus) visual and acoustic encounter rates was quantitatively evaluated using hourly counts of detected whales during shipboard surveys off southern California. Encounter rates were estimated using temporal, geographic, and weather variables within a generalized additive model framework. Visual encounters (2.06 animals/h, CV = 0.10) varied with subregion, Julian day, time of day, and year. Acoustic encounters of whales producing pulsed A and tonal B call sequences (song; 0.65 animals/h, CV = 0.06) varied by Julian day, survey mode (transit or stationary), and subregion, and encounters of whales producing downswept (D) calls (0.41 …
Noaa's Climate Database Modernization Program: Rescuing, Archiving, And Digitizing History, Lesley-Ann Dupigny-Giroux, Thomas F. Ross, Joe D. Elms, Raymond Truesdell, Stephen R. Doty
Noaa's Climate Database Modernization Program: Rescuing, Archiving, And Digitizing History, Lesley-Ann Dupigny-Giroux, Thomas F. Ross, Joe D. Elms, Raymond Truesdell, Stephen R. Doty
United States Department of Commerce: Staff Publications
Historic weather, climate, and ocean observations from as far back as the mid-1700s are being made easily available on the Internet for use in studying global climate variability and change and for helping to improve mitigation and response. The National Oceanic and Atmospheric Administration (NOAA) Climate Database Modernization Program (CDMP) began in 2000 with a major emphasis on imaging and keying worldwide climate and environmental records from the eighteenth through the twentieth centuries. This multimillion dollar program is an ongoing effort to process data from the United States and elsewhere, improve its access, and maintain a permanent data archive. The …