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North Pacific Right Whale (Eubalaena Japonica) Seasonal And Diel Calling Patterns From Long-Term Acoustic Recordings In The Southeastern Bering Sea, 2000–2006, Lisa Munger, Sean Wiggins, Sue Moore, John Hildebrand

United States Department of Commerce: Staff Publications

We assessed North Pacific right whale (Eubalaena japonica) seasonal and daily calling patterns in the southeastern Bering Sea (SEBS) using long-term hydrophone recordings from October 2000 through January 2006. We detected right whale calls on the SEBS middle shelf (<100 m depth) as early as May, intermittently throughout summer and fall, and as late as December. Calls also were detected on one day in June 2005 on the SEBS slope (>1,000 m), but were not detected near Kodiak Island from April to August 2003. In months with calls, detections occurred on more days in July–October (≥6 d/mo), than from May to June or November to December (≤3 d/mo). Calls were clustered in time and were usually detected on 1–3 consecutive days with a median interval of 6.5 d …

Demographics And Spatio-Temporal Signature Of The Biotoxin Domoic Acid In California Sea Lion (Zalophus Californianus) Stranding Records, Adriana Bejarano, Frances Gulland, Tracey Goldstein, Judy St. Leger, Michele Hunter, Lori Schwacke, Frances Vandolah, Teri Rowles

United States Department of Commerce: Staff Publications

California sea lions (Zalophus californianus) in otherwise good nutritional condition have been consistently affected by the marine biotoxin domoic acid since the late 1990s. In this study we evaluated the temporal and spatial stranding patterns of suspected and confirmed cases of domoic acid intoxicated sea lions from 1998 to 2006, using records of strandings along the California coast obtained from members of the California Marine Mammal Stranding Network. The majority of domoic acid cases were adult females (47%–82% of the total annual domoic acid cases), a contrast to strandings that were not related to domoic acid, which were …

Arctic Report Card 2008: Tracking Recent Environmental Changes, J. Overland, J. Walsh, M. Wang, J. Richter-Menge, J. Comiso, W. Meier, S. Nghiem, D. Perovich, A. Proshutinsky, J. Morison, I. Ashik, E. Carmack, I. Frolov, J. C. Gascard, M. Itoh, R. Krishfield, F. Mclaughlin, I . Polyakov, B. Rudels, U. Schauer, K . Shimada, V. Sokolov, M. Steele, M.-L. Timmermans, J. Toole, V. Romanovsky, R. Armstrong, A. Shiklomanov, D. Walker, G. Jia, J. Box, J. Cappelen, D. Bromwich, L.-S. Bai, T. Mote, B. Veenhuis, N. Mikkelsen, A. Weidick, Michael Svoboda, D. Russell, M.J.J.E. Loonen, C. Zöckler, B. Ebbinge, M. Simpkins, C.D. Sawatzky, J.D. Reist

United States Department of Commerce: Staff Publications

There continues to be widespread and, in some cases, dramatic evidence of an overall warming of the Arctic system.

Atmosphere: 5° C temperature increases were recorded in autumn

Ocean: Observed increase in temperature of surface and deep ocean layers

Sea Ice: Near-record minimum summer sea ice extent

Greenland: Records set in both duration and extent of summer surface melt

Biology: Fisheries and marine mammals impacted by loss of sea ice

Land: Permafrost temperatures tend to increase, while snow extent tends to decrease The Arctic Report Card is introduced as a means of presenting clear, reliable and concise information on recent …

Florida Red Tide And Brevetoxins: Association And Exposure In Live Resident Bottlenose Dolphins (Tursiops Truncates) In The Eastern Gulf Of Mexico, U.S.A., Spencer Fire, Leanne Flewelling, Zhihong Wang, Jerome Naar, Michael Henry, Richard Pierce, Randall Wells

United States Department of Commerce: Staff Publications

Bottlenose dolphins (Tursiops truncatus) along the Gulf of Mexico are frequently exposed to blooms of the toxic alga, Karenia brevis, and brevetoxins associated with these blooms have been implicated in several dolphin mortality events. Studies on brevetoxin accumulation in dolphins have typically focused on analyses of carcasses from large-scale die-offs; however, data are scarce for brevetoxin loads in live individuals frequently exposed to K. brevis blooms. This study investigated in vivo brevetoxin exposure in free-ranging bottlenose dolphins resident to Sarasota Bay, Florida, utilizing samples collected during health assessments performed during multiple K. brevis blooms occurring from 2003 …

Acoustic Pingers Eliminate Beaked Whale Bycatch In A Gill Net Fishery, James Carretta, Jay Barlow, Lyle Enriquez

United States Department of Commerce: Staff Publications

Bycatch of beaked whales in gill net fisheries has been documented worldwide (Nicholson 1954, Di Natale 1994, Read 1994, Siliciliano 1994, Julian and Beeson 1998, Waring et al. 2006). Acoustic pingers have been successfully used to reduce bycatch of harbor porpoises (Phocoena phocoena) (Kraus et al. 1997, Trippel et al. 1999, Gearin et al. 2000) and common dolphins (Delphinus delphis) (Barlow and Cameron 2003), but pinger efficacy in reducing beaked whale bycatch has never been evaluated due to the rarity of beaked whale entanglements in fisheries.We report that bycatch of beaked whales in a California drift …

An Assessment Of Shore-Based Counts Of Gray Whales, David Rugh, Marcia Muto, Roderick Hobbs, James Lerczak

United States Department of Commerce: Staff Publications

Counts of migrating whales depend on accurate sightings data. In this study, teams of shore-based observers independently tracked whale pods during the southbound migration of gray whales (Eschrichtius robustus) while a routine (“standard watch”) census was underway. A comparison of sighting records showed that time and location accuracy was limited to 45 s, 3◦ (magnetic) horizontally, and 0.0057◦ (0.2 reticles) vertically. Of 242 attempts to track whale groups, 72 failed, 120 were “good tracks,” and 83 qualified as “best tracks” because they had ≥8 sightings/pod, ≥16-min observation time, and unequivocal matches to sightings in the standard watch during …

A General Framework For The Analysis Of Animal Resource Selection From Telemetry Data, Devin S. Johnson, Dana L. Thomas, Jay M. Ver Hoef, Aaron Christ

United States Department of Commerce: Staff Publications

We propose a general framework for the analysis of animal telemetry data through the use of weighted distributions. It is shown that several interpretations of resource selection functions arise when constructed from the ratio of a use and availability distribution. Through the proposed general framework, several popular resource selection models are shown to be special cases of the general model by making assumptions about animal movement and behavior. The weighted distribution framework is shown to be easily extended to readily account for telemetry data that are highly auto-correlated; as is typical with use of new technology such as global positioning …

Eastern Temperate North Pacific Offshore Killer Whales (Orcinus Orca): Occurrence, Movements, And Insights Into Feeding Ecology, Marilyn Dahlheim, Alisa Schulman-Janiger, Nancy Black, Richard Ternullo, Dave Ellifrit, Kenneth Balcomb Iii

United States Department of Commerce: Staff Publications

Beginning in the late 1980s, large groups of previously unidentified killer whales (Orcinus orca) were sighted off the west coast of Vancouver Island and in the Queen Charlotte Islands, British Columbia. Scientists working in this region produced two killer whale photo-identification catalogues that included both transient (mammal-eating) whales and 65 individual whales that investigators believed represented a distinct killer whale community (Ford et al. 1992, Heise et al. 1993). It was thought that these killer whales maintained a generally offshore distribution and were provisionally termed “offshores”; a term that has since been used as a population identifier for …

False Killer Whales (Pseudorca Crassidens) Around The Main Hawaiian Islands: Long-Term Site Fidelity, Inter-Island Movements, And Association Patterns, Robin Baird, Antoinette Gorgone, Daniel Mcsweeney, Daniel Webster, Dan Salden, Mark Deakos, Allan Ligon, Gregory Schorr, Jay Barlow, Sabre Mahaffy

United States Department of Commerce: Staff Publications

Despite their world-wide distribution throughout the tropics and subtropics, false killer whales (Pseudorca crassidens) are one of the lesser-known large odontocetes. Genetic evidence indicates a demographically isolated population around the main Hawaiian Islands. We examine site fidelity, movements and association patterns in this population using data from directed surveys and opportunistic photographs from 1986 to 2007. This species was only infrequently encountered, and while found in depths from 38 to 4,331 m, sighting rates were greatest in depths>3,000 m. We photo-identified 152 distinctive individuals. Resighting rates were high, with an average of 76.8% of distinctive individuals within …

Eastern Temperate North Pacific Offshore Killer Whales (Orcinus Orca): Occurrence, Movements, And Insights Into Feeding Ecology, Marilyn Dalheim, Alisa Schulman-Janiger, Nancy Black, Richard Ternullo, Dave Ellifrit, Kenneth Balcomb Iii

United States Department of Commerce: Staff Publications

Beginning in the late 1980s, large groups of previously unidentified killer whales (Orcinus orca) were sighted off the west coast of Vancouver Island and in the Queen Charlotte Islands, British Columbia. Scientists working in this region produced two killer whale photo-identification catalogues that included both transient (mammal-eating) whales and 65 individual whales that investigators believed represented a distinct killer whale community (Ford et al. 1992, Heise et al. 1993). It was thought that these killer whales maintained a generally offshore distribution and were provisionally termed “offshores”; a term that has since been used as a population identifier for …

Use Of Chemical Tracers To Assess Diet And Persistent Organic Pollutants In Antarctic Type C Killer Whales, Margaret Krahn, Robert Pitman, Douglas Burrows, David Herman, Ronald Pearce

United States Department of Commerce: Staff Publications

Measuring chemical tracers in tissues of marine predators provides insight into the prey consumed and the predator’s contaminant exposure. In this study, samples from Type C killer whales (Orcinus orca) biopsied in Antarctica were analyzed for chemical tracers (i.e., stable isotopes of carbon and nitrogen, fatty acids, and persistent organic pollutants [POPs]). Profiles of these individual tracers were very different from those of killer whale populations that have been studied in the eastern North and eastern Tropical Pacific. For example, δ¹³C and δ¹⁵N stable isotope values and most POP concentrations were significantly lower in …

Diel Variation In Beaked Whale Diving Behavior, Robin Baird, Daniel Webster, Gregory Schorr, Daniel Mcsweeney, Jay Barlow

United States Department of Commerce: Staff Publications

We investigate diel variation in beaked whale diving behavior using data from time–depth recorders deployed on six Blainville’s (Mesoplodon densirostris) (255 h) and two Cuvier’s (Ziphius cavirostris) (34 h) beaked whales. Deep foraging dives (>800 m) occurred at similar rates during the day and night for Blainville’s beaked whales, and there were no significant diel differences in ascent rates, descent rates, or mean or maximum depths or durations for deep dives. Dive to mid-water depths (100–600 m) occurred significantly more often during the day (mean = 1.59 h−1) than at night (mean = 0.26 h−1). …

Geographic Variation In Killer Whale Attacks On Humpback Whales In The North Pacific: Implications For Predation Pressure, Gretchen H. Steiger, John Calambokidis, Janice M. Straley, Louis M. Herman, Salvatore Cerchio, Dan R. Salden, Jorge Urban-R., Jeff K. Jacobsen, Olga Von Ziegesar, Kenneth C. Balcomb, Christine M. Gabriele, Marilyn E. Dahlheim, Senzo Uchida, John K. B. Ford, Paloma Ladron De Guevara-P., Manami Yamaguchi, Jay Barlow

United States Department of Commerce: Staff Publications

We examined the incidence of rake mark scars from killer whales Orcinus orca on the flukes of humpback whales Megaptera novaeangliae throughout the North Pacific to assess geo- graphic variation in predation pressure. We used 3650 identification photographs from 16 wintering or feeding areas collected during 1990 to 1993 to determine conservative estimates in the percentage of whales with rake mark scarring. Dramatic differences were seen in the incidence of rake marks among regions, with highest rates on wintering grounds off Mexico (26 vs. 14 % at others) and feeding areas off California (20 vs. 6% at others), 2 areas …

Seasonal And Annual Variation In Body Condition Of Western Gray Whales Off Northeastern Sakhalin Island, Russia, Amanda L. Bradford, David W. Weller, Yulia V. Ivashchenko, Alexander M. Burdin, Robert L. Brownell Jr.

United States Department of Commerce: Staff Publications

The western gray whale population (Eschrichtius robustus) is critically endangered and its potential for recovery is uncertain. Along with other natural and anthropogenic threats, western gray whales are susceptible to nutritional stress, known from regular observations of individual whales in compromised body condition. Thus, the ability to visually quantify the relative body condition of free-ranging western gray whales and evaluate how this condition varies seasonally and annually is needed. A photo-identification study of western gray whales on their feeding ground off the northeastern coast of Sakhalin Island, Russia, produced a large dataset of digital, film, and video images …

Diet Of The Striped Dolphin, Stenella Coeruleoalba, In The Eastern Tropical Pacific Ocean, William F. Perrin, Kelly M. Robertson, William A. Walker

United States Department of Commerce: Staff Publications

Knowledge of the trophic ecology of pelagic dolphins is important to understanding the ecosystem of the eastern tropical Pacific. Mesopelagic species predominated in the diet of 131 striped dolphins; the myctophid Lampanyctus parvicauda, a melamphaeid Melamphaes sp., and the enoploteuthid squid Abraliopsis affinis were the most numerous and most prevalent. Composition varied among four regions; fish predominated in three southerly regions, and fish and cephalopods occurred in about equal numbers in a region close to the northern tropical convergence. Prey for which length could be estimated ranged from about 2 to 17 cm in length. Most feeding occurred at …

Environmental Policy Aid Under Uncertainty, J. Mysiak, J. D. Brown, J. M. L. Jansen, N. W. T. Quinn

United States Department of Commerce: Staff Publications

Recent emphasis on uncertainty in environmental decision making reflects numerous changes in environmental science and policy making over the past few decades. Firstly, environmental policy problems increasingly involve large, interconnected and complex social choices. For example, climate change, ozone depletion, biodiversity loss, genetically-engineered crops, environment-related diseases and health risks involve large scale, long-term impacts, whose precise causes and consequences are often poorly understood. Given these uncertainties and the risk of irreversible environmental changes, different perspectives about the nature, policy implications, or even the existence of a problem, are inevitable (Rittel and Webber, 1973; Sarewitz, 2004).

Genetic Isolation And Morphological Divergence Of Black Sea Bottlenose Dolphins, Karine A. Viaud-Martineza, Robert L. Brownell Jr., Andrew J. Bohonak, Anastasia Komnenouc

United States Department of Commerce: Staff Publications

The Black Sea is a semi-enclosed body of water that differs from the adjacent Mediterranean Sea in terms of its biodiversity, oceanographical and ecological characteristics. There is growing international concern about pollution in the Black Sea and other anthropogenic threats to its fauna. The bottlenose dolphin (Tursiops truncatus) is one of three species of cetaceans living in the Azov-Black Sea basin. Despite considerable research on bottlenose dolphins elsewhere, the extent of human impacts on the Black Sea populations is unknown. Previous attempts to award special conservation status to Black Sea cetaceans have failed specifically because policy makers have viewed their …

Some Fungi And Water Molds In Waters Of Lake Michigan With Emphasis On Those Associated With The Benthic Amphipod Diporeia Spp., Bozena Kiziewicz, Thomas F. Nalepa

United States Department of Commerce: Staff Publications

To determine types of fungi in the water and associated with the benthic amphipod Diporeia spp., samples were collected at various depths in Lake Michigan in an area where the Diporeia population was in a severe state of decline. No fungi were found associated with living, freshly-dead, or dried Diporeia cultured separately from Lake Michigan water. When dead Diporeia and other organic substrates (snake skin and hemp seeds) were used to grow fungi in Lake Michigan water, a rich and diverse fungal and water mold community was revealed. A total of 31 species were found, with the most common genera …

Letter To The Editor: Comment On ‘‘Toxicity Of Weathered Exxon Valdez Crude Oil To Pink Salmon Embryos’’, Ron A. Heintz, Jeffrey W. Short, Stanley D. Rice, Mark G. Carls

United States Department of Commerce: Staff Publications

We take issue with an article by Brannon et al. in Environmental Toxicology and Chemistry questioning the validity of our work on the toxicity of petroleum-derived polycyclic aromatic hydrocarbons (PAHs) to the early life stages of fish. Beginning in 1997, we published a series of articles demonstrating adverse effects in response to PAH exposure at concentrations in the low parts per billion. Based on their attempt to reproduce our results, Brannon et al. argue that the effects we described were an artifact caused by contact with PAH-laden oil microdroplets instead of dissolved PAHs and, therefore, that our results likely are …

Biological Background On Bottlenose Dolphins (Tursiops Spp.) In The 'Live-Capture' Trade And Specifically On The Indo-Pacific Bottlenose Dolphin, T. Aduncus, Robert L. Brownell Jr., Randall Reeves

United States Department of Commerce: Staff Publications

The most significant cetacean trade items until commercial whaling all but ceased in the 1990s (aside from scientific exchanges of tissues etc.) were meat and blubber from baleen whales for human consumption. Since then, live dolphins and 'small' whales for display (and to some extent for research, military use, and 'therapy') have become the most significant cetacean 'products' in international trade. Trade in live cetaceans is presently dominated by bottlenose dolphins (Tursiops spp.), beluga whales (Debhinapterns leucas) and to a lesser extent killer whales (Orcinus orca) (Fisher and Reeves 2005). In the past, most of …

Hunting Cetaceans With Sound: A Worldwide Review, Robert L. Brownell Jr., Douglas P. Nowacek, Katherine Ralls

United States Department of Commerce: Staff Publications

Cetaceans are sensitive to a variety of anthropogenic sounds because they normally use sound to navigate, communicate and capture prey. This paper reviews some fisheries that have taken advantage of this sensitivity by using sound to help capture numerous species of dolphins and whales. Fishermen in many parts of the world have independently developed methods that use sounds to drive (herd) various species of small cetaceans so that they can be killed and used for food, culled (i.e. to offset competition for fish), help capture fish (e.g. in the Eastern Tropical Pacific) or be taken into captivity. It is well …

An Animal Movement Model Incorporating Home Range And Habitat Selection, Aaron Christ, Jay Ver Hoef, Dale L. Zimmerman

United States Department of Commerce: Staff Publications

Wildlife biologists are often interested in how an animal uses space and the habitat resources within that space. We propose a single model that estimates an animal’s home range and habitat selection parameters within that range while accounting for the inherent autocorrelation in frequently sampled telemetry data. The model is applied to brown bear telemetry data in southeast Alaska.

Spatial Methods For Plot-Based Sampling Of Wildlife Populations, Jay M. Ver Hoef

United States Department of Commerce: Staff Publications

Classical sampling methods can be used to estimate the mean of a finite or infinite population. Block kriging also estimates the mean, but of an infinite population in a continuous spatial domain. In this paper, I consider a finite population version of block kriging (FPBK) for plot-based sampling. The data are assumed to come from a spatial stochastic process. Minimizing mean-squared-prediction errors yields best linear unbiased predictions that are a finite population version of block kriging. FPBK has versions comparable to simple random sampling and stratified sampling, and includes the general linear model. This method has been tested for several …

Determining Spatial And Temporal Scales For Management: Lessons From Whaling, P J. Clapham, Alex Aguilar, Leila Hatch

United States Department of Commerce: Staff Publications

Selection of the appropriate management unit is critical to the conservation of animal populations. Defining such units depends upon knowledge of population structure and upon the timescale being considered. Here, we examine the trajectory of eleven subpopulations of five species of baleen whales to investigate temporal and spatial scales in management. These subpopulations were all extirpated by commercial whaling, and no recovery or repopulation has occurred since. In these cases, time elapsed since commercial extinction ranges from four decades to almost four centuries. We propose that these subpopulations did not recover either because cultural memory of the habitat has been …

Harbor Seal Population Decline In The Aleutian Archipelago, Robert Small, Peter Boveng, G. Vernon Byrd, David Withrow

United States Department of Commerce: Staff Publications

Populations of Steller sea lions, northern fur seals, and northern sea otters declined substantially during recent decades in the Bering Sea and Aleutian Islands region, yet the population status of harbor seals has not been assessed adequately. We determined that counts obtained during skiff-based surveys conducted in 1977–1982 represent the earliest estimate of harbor seal abundance throughout the Aleutian Islands. By comparing counts from 106 islands surveyed in 1977–1982 (8,601 seals) with counts from the same islands during a 1999 aerial survey (2,859 seals), we observed a 67% decline over the ∼20-yr period. Regionally, the largest decline of 86% was …

Design And Field Methods For Sighting Surveys Of Cetaceans In Coastal And Riverine Habitats, Steve Dawson, Paul Wade, Elisabeth Slooten, Jay Barlow

United States Department of Commerce: Staff Publications

1. Dolphins and porpoises in coastal and/or riverine habitats face serious conservation threats, yet surveys of their abundance are often especially difficult due to the challenges imposed by the habitats. Because many of these species occur in developing countries, lack of resources imposes a further set of challenges.

2. We offer advice on designing and conducting line-transect surveys with a focus on sound, practical, design rather than analytical sophistication, and we attempt, where possible, to offer simple, inexpensive solutions.

3. We guide the reader through the questions of what kind of survey should be done, whether by boat or aircraft, …

Population Abundance And Growth Rate Of Western Gray Whales Eschrichtius Robustus, Amanda L. Bradford, David W. Weller, Paul R. Wade, Alexander M. Burdin, Robert L. Brownell Jr.

United States Department of Commerce: Staff Publications

The western population of gray whales Eschrichtius robustus is one of the most endangered whale populations in the world. Recent studies of this population off the northeastern coast of Sakhalin Island, Russia, have produced a photographic dataset that was utilized for the first mark-recapture assessment of western gray whale abundance. Given encounter histories of 129 individually identified whales spanning 25 monthly capture occasions from 1997 to 2003, a closed capture estimator was employed to estimate the number of individuals using the study area in each year. Temporary emigration probabilities were then applied to the closed capture estimates to enumerate the …

Taking Account Of Dependent Species In Management Of The Southern Ocean Krill Fishery: Estimating Crabeater Seal Abundance Off East Antarctica, Colin Southwell, Charles G. M. Paxton, David Borchers, Peter Boveng, William De La Mare

United States Department of Commerce: Staff Publications

1. The crabeater seal Lobodon carcinophaga is considered to be a key species in the krill-based food web of the Southern Ocean. Reliable estimates of the abundance of this species are necessary to allow the development of multispecies, predator–prey models as a basis for management of the krill fishery in the Southern Ocean.

2. A survey of crabeater seal abundance was undertaken in 1500 000 km² of pack-ice off east Antarctica between longitudes 64–150° E during the austral summer of 1999/2000. Sighting surveys, using double observer line transect methods, were conducted from an icebreaker and two helicopters to estimate …

Linking Colonies To Fisheries: Spatio-Temporal Overlap Between Common Murres (Uria Aalge) From Tatoosh Island And Coastal Gillnet Fisheries In The Pacific Northwest, Usa, Nathalie J. Hamela, Julia K. Parrisha, Jeff Laake

United States Department of Commerce: Staff Publications

The population-level impact of seabird bycatch is difficult to assess because colony-of-origin is often unknown. As an alternative and complementary approach to ship-derived observations, we assessed the relative potential for bycatch of a known seabird population by quantifying spatio-temporal overlap with local fisheries. Common murres (Uria aalge) have been reported as the most abundant seabird inadvertently caught in Washington and British Columbia coastal gillnet fisheries. In 1999–2001, we tracked 48 common murres from Tatoosh Island, the closest colony to the fisheries, during post-breeding. Using capture- mark-recapture models, we estimated weekly murre movement probabilities to/from three strata (offshore of, …

Abundances Of The Amphipod Diporeia Spp. And The Mussels Dreissena Polymorpha And Dreissena Rostriformis Bugensis In Lake Michigan In 1994-1995, 2000, And 2005, Thomas F. Nalepa, David L. Fanslow, Gregory A. Lang, Derek B. Lamarand, Laurie G. Cummins, Glenn S. Carter

United States Department of Commerce: Staff Publications

This technical report provides basic results of benthic surveys conducted in Lake Michigan in 1994-1995, 2000, and 2005. The focus of these surveys was to assess lakewide trends in abundances of the amphipod Diporeia spp., the zebra mussel (Dreissena polymorpha), and the quagga mussel (Dreissena rostriformis bugensis). These lakewide surveys were an expansion of a monitoring program in the southern basin that has examined trends in the abundance and composition of the macroinvertebrate community since 1980 (Nalepa 1987, Nalepa et al. 1998). The original purpose of the monitoring program was to assess the response of the …