Waters Of Washington Research Articles

Summer distribution patterns of southern resident killer whales Orcinus orca: core areas and spatial segregation of social groups

A diverse range of marine wildlife species respond to dynamic environments and patchy resources with variations in their distribution pattern. For many cetacean species, highly structured social systems add to the complexity of modeling distribution patterns and understanding the effects on population viability. Southern resident killer whales Orcinus orca are comprised of 3 distinct, yet cohesive, matrilineally related social groups called pods, and recent population declines have prompted conservation actions in the US and Canada, including listings as an endangered species. Habitat protection is a major component of each listing, yet little is known about pod-specific core areas or patterns of space use for this population. Using 6 yr of sighting information within the inshore waters of Washington and British Columbia, we modeled pod-specific summer distribution and measured relative variation in the density of sightings on a uniform spatial grid. Our results indicate that the pods exhibit complex, non-uniform summer space-use patterns. Although some regions are used in common by all pods, some areas are used almost exclusively by individual pods or certain combinations of pods, indicating specialization to particular areas. Our results indicate that pod groups display variable patterns of space use; therefore, each pod may experience unique habitat conditions or exposure to potential risk factors. This result is highly relevant when considering pod- specific mortality rates and the relative contribution of each pod to overall population trends. Our analyses highlight important areas of conservation, and provide the necessary description for pod- focused conservation initiatives.

About the Cover.

Next article FreeAbout the CoverPDFPDF PLUSFull Text Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinked InRedditEmailQR Code SectionsMoreCoverThe sea star Pisaster ochraceus is a dominant intertidal predator in the northeast Pacific Ocean, and holds the distinction of being the original "keystone" species* used in framing the concept that the stability of a biological community can be disproportionately influenced by a single species-usually a predator. P. ochraceus feeds on a variety of sessile invertebrates, and controls local diversity by preying preferentially on competitively dominant mussels. It is abundant on rocky intertidal shores from Alaska to the Baja Peninsula in Mexico.Over most of this range, several color morphs are present, including orange and a variety intergrading purples and browns. Although multiple color morphs are present at most sites throughout the range (the animals shown on the cover were photographed in Pacific Grove, California), P. ochraceus populations in the protected waters of northern Puget Sound (Washington) and the southern Strait of Georgia (British Columbia) are almost entirely bright purple. The underlying causes of the P. ochraceus color polymorphism, and the regional variation in the frequency of color morphs, remain a mystery.As reported by Harley et al. on page 248 of this issue, genetic structure in P. ochraceus from Alaska to southern California, including the inland waters of Washington and British Columbia, is very low. This suggests that variation in color frequencies is not a vestige of population isolation during the last ice age. Color frequencies are also unrelated to adult size and the frequency of injury. There are, however, suggestive relationships between color morph frequency and diet and local salinity. The authors propose that the polymorphism may well have an underlying genetic component, but that the regional-scale patterns in color are under ecological control.Credits: Photo, Chris Harley (University of British Columbia); cover layout, Beth Liles (Marine Biological Laboratory).*Paine, R. T. 1969. A note on trophic complexity and community stability. Am Nat. 103:91-93. Next article DetailsFiguresReferencesCited by The Biological Bulletin Volume 211, Number 3December 2006 Published in association with the Marine Biological Laboratory Article DOIhttps://doi.org/10.1086/BBLv211n3cover Views: 173Total views on this site © 2006 by Marine Biological Laboratory. All rights reserved.PDF download Crossref reports no articles citing this article.

KILLER WHALE ATTACKS ON MINKE WHALES: PREY CAPTURE AND ANTIPREDATOR TACTICS

We describe nine incidents of predation or attempted predation of minke whales (Balaenoptera acutorostrata) by mammal-hunting “transient” killer whales (Orcinus orca) in coastal waters of British Columbia, Washington, and southeastern Alaska. Pursuits of minke whales were characterized by prolonged chases on a straight heading at velocities of 15–30 km/h. In four of the nine cases the adultsized minke whale gradually outdistanced the killer whales, which abandoned the high-speed pursuit after 0.5–1 h. In one case the minke beached itself and died. Four attacks were successful. In one instance a subadult minke was killed in open water following a chase. In two cases the fleeing minke entered a confined bay and was killed by the killer whales. One adult minke was taken after apparently attempting to seek cover beside a large sailboat. Minke whales made no attempt to physically defend themselves and were killed by repeated ramming or by asphyxiation. Although killer whales are capable of sprinting speeds greater than those of minke whales, it appears that adult minkes can maintain higher sustained speeds and evade capture if sufficient space for an extended escape trajectory is available. Successful predation of minke whales in coastal waters is rare compared to pinnipeds and small cetaceans, the main prey of transient killer whales.

EVALUATION OF THE CONSEQUENCES OF VARIOUS RESPONSE OPTIONS USING MODELING OF FATE, EFFECTS AND NRDA COSTS OF OIL SPILLS INTO WASHINGTON WATERS

ABSTRACT Oil spill fate and effects modeling and analysis were performed to evaluate the implications of spill response options being considered by the Washington State Department of Ecology in their rulemaking related to oil spill preparedness (WA State Contingency Plan Rule). The impacts of potential spills in Washington's outer coast, sound and river environments were modeled varying response options and operational timing, including use of conventional mechanical containment and recovery operations; dispersant application with concurrent mechanical containment and recovery; and in-situ burning with concurrent mechanical containment and recovery. US Coast Guard federal response capability standards, current Washington State standards, and potential theoretical higher response capability standards were simulated for scenarios involving spills of crude oil, bunker fuel and diesel into Washington waters (in the Strait of Georgia, Strait of Juan de Fuca, outer coast, and lower and upper Columbia River). The modeling was performed in probabilistic mode, i.e., by randomly varying location along tanker routes, spill date, and time, and so environmental conditions during and after the release among potential conditions that would occur. The model results were analyzed to estimate mean, standard deviation (SD), and 5th, 50th and 95th percentile results for surface water and shoreline oiling, water column and sediment contamination, biological impacts, and natural resource damages (NRD). NRD costs were based on the Washington Compensation Schedule and Oil Pollution Act (OPA) NRD procedures involving compensatory restoration scaling and associated costs. Response costs and socioeconomic damages were evaluated in a companion study by D.S. Etkin (Environmental Research Consulting). The fates, impacts and NRD cost results for two scenarios are presented here: those for the outer coast spills assuming (1) only protective booming and (2) protective booming plus the mechanical removal up to Washington State standards. The results of these and other scenarios are being incorporated into a rulemaking process and cost-benefit analysis by the Department of Ecology.

Factors influencing the diving behaviour of fish-eating killer whales: sex differences and diel and interannual variation in diving rates

Diving behaviour of air-breathing vertebrates may be influenced by a variety of factors including age, body size, and changes in prey behaviour and (or) abundance over both short and long timescales. We studied the diving behaviour of a highly sexually dimorphic odontocete cetacean, the killer whale, Orcinus orca (L., 1758), using suction-cup-attached time-depth recorders (TDRs). We tested the hypotheses that dive rates (no. of dives/h greater than or equal to specific depths) of fish-eating killer whales varied between males and females, with age, between day and night, and among pods and years. Data were used from 34 TDR deployments between 1993 and 2002 in the inshore waters of southern British Columbia, Canada, and Washington, USA. Dive rates did not change with age or differ among pods or between males and females, although analyses restricted to adults showed that adult males dove deep significantly more frequently than adult females during the day. For all whales, dive rates and swim speeds were greater during the day than at night, suggesting decreased activity levels at night. Dive rates to deeper depths during the day decreased over the study, suggesting a long-term change in prey behaviour or abundance, though uncertainty regarding the diet of this population precludes determination of the cause of such changes.

17 Restoration Techniques For Nereocystis Luetkeana (Mertens) Postels Et Ruprecht (Bull Kelp)

The establishment and growth of Nereocystis luetkeana communities are limited by many environmental and biotic factors. Temperature, light quantity and quality, turbidity, salinity, wave motion, and competition for space and light all determine where populations of this annual kelp will establish and persist from season to season. Like much of the nearshore marine vegetation in Puget Sound and the San Juan Archipelago, Nereocystis is negatively impacted by anthropogenic disturbances, such as shoreline development and sediment loading from terrestrial erosion. These events can alter or eliminate optimal habitat and conditions that support adult populations, as well as interfere with the development of the microscopic life stages. Various techniques to establish a Nereocystis bed in the northern waters of Washington, USA are examined and will serve as a model for future restoration efforts. Techniques being investigated are as follows: 1) out‐planting Nereocystis during different seasons; 2) out‐planting at different stages of maturity, i.e., zoospore and microscopic sporophyte (0.5–1.0 mm blade length) from cultures; 3) out‐planting directly on natural substratum versus at elevated positions; 4) transplanting juveniles (10 cm stipe length); and, 5) seeding natural substratum with out‐planted sori (sporophylls), bypassing the lab culturing phase. Results of this study will help define the optimal restoration procedure, including environmental parameters, for Nereocystis in order to aid coastal managers in the implementation of nearshore restoration projects. Preliminary results will be presented.

Trends and Status of Harbor Seals in Washington State: 1978-1999

In the first half of the 20th century, harbor seal (Phoca vitulina richardsi) numbers were severely reduced in Washington state by a state-financed population control program. Seal numbers began to recover after the cessation of bounties in 1960 and passage of the Marine Mammal Protection Act (MMPA) in 1972. From 1978 to 1999, aerial surveys were flown at midday low tides during pupping season to determine the distribution and abundance of harbor seals in Washington. We used exponential and generalized logistic models to examine population trends and size relative to maximum net productivity level (MNPL) and carrying capacity (K). Observed harbor seal abundance has increased 3-fold since 1978, and estimated abundance has increased 7 to 10-fold since 1970. Under National Marine Fisheries Service (NMFS) management, Washington harbor seals are divided into 2 stocks: coastal and inland waters. The observed population size for 1999 is very close to the predicted Kfor both stocks. The current management philosophy for marine mammals that assumes a density-dependent response in population growth with MNPL > K/2 is supported by growth of harbor seal stocks in Washington waters.

Innovative International Protection Efforts in Washington and British Columbia Waters

ABSTRACT In recognition of the value of the marine resources throughout Puget Sound, the Strait of Juan de Fuca and its approaches along the Washington coast and the outer coast of British Columbia, several recent international collaborations have been undertaken which provide important information regarding vessel tracking through these sensitive areas. The first endeavor, undertaken by the National Oceanic and Atmospheric Administration's (NOAA's) Olympic Coast National Marine Sanctuary (OCNMS), involves the utilization of a desktop Geographic Information System (GIS) to analyze and display vessel track data collected by the Canadian Coast Guard from their radar-based Cooperative Vessel Traffic Management System (CVTMS) located at Tofino on Vancouver Island, British Columbia. The OCNMS system has allowed Sanctuary managers to verify compliance by mariners with guidance regarding the Area To Be Avoided (ATBA) within and proximal to the OCNMS. A second undertaking, enacted by an international coalition of marine shipping industry interests, involves the near real-time tracking of tugboat assets within the Strait of Juan de Fuca, Puget Sound, and the Strait of Georgia. The International Tug of Opportunity System (ITOS) involves the use of a Differential Geographic Positioning System (DGPS) and radio modem-based Automated Information System (AIS) whereby the positions of participating tugboats are tracked in near real-time, displayed on an Electronic Chart Display and Information System (ECDIS), and integrated with a database containing critical information about tugboat capabilities. ITOS watchstanders can identify the nearest available participating resources to any vessel requiring assistance and provide the U.S. or Canadian Coast Guard or the vessel master with time-critical emergency contact information.

Atlantic salmon in the North Pacific

The first catches of Atlantic salmon, Salmo salar L., in British Columbia (BC) waters occurred in 1987. The first reported escape of Atlantic salmon (2000 individuals) occurred in 1988. From 1988 to 1995, 97 799 Atlantic salmon were reported escaped from net pens in BC but the true number was higher as not all escapes are reported. Since 1987 a total of 9096 Atlantic salmon was caught in the coastal marine waters of BC, Washington and Alaska, and 188 were caught in fresh water. Most catches occurred in the Johnstone Strait area, where the abundance of salmon farms is highest. The most distant recovery occurred in 1994 when an Atlantic salmon was caught near the western end of the Alaska Peninsula. There have been no reports of successful reproduction of Atlantic salmon in the wild and no feral juveniles have been found. Atlantic salmon caught in the ocean in BC have substantial amounts of adipose tissue and they are heavier at length than fish caught in Alaska. The proportion of fish with prey items in their stomachs is generally low but higher in Alaska (13.1%) than in BC (5.8%). Most fish caught in fresh water are either maturing or mature.

Temporal and Spatial Variation in Fecundity of Yellowtail Rockfish

Abstract Fecundities of the commercially important yellowtail rockfish Sebastes flavidus were compared to determine interannual variability and geographic variation, which will assist in stock assessment, characterization, and management. Gravimetrically estimated fecundities were compared in 1985–1991 between California, the southern extent of the species' distribution, and coastal waters of Washington, near the center of the species' abundance, where yellowtail rockfish are most heavily fished. California yellowtail rockfish were older, smaller in weight and length, and had smaller mesenteric fat deposits and more extensive disease and parasite pathologies than Washington fish. Egg production of this comparatively fecund viviparous fish increased linearly and sigmoidally with body weight and length, and asymptotically with age. Significant interannual differences were found in fecundities of young fish ( age 14) or in ...

Toxic diatoms in western Washington waters (U.S. west coast)

Members of the planktonic diatom genus Pseudonitzschia H. Peragallo, P. pungens (Grun.) Hasle f. multiseries (Hasle) Hasle and P. australis Frenguelli, that may produce the marine biotoxin, domoic acid, have been recognized in western Washington waters. Their distribution is not well-known in this area, probably because they often have been misidentified. However, they appear to be relatively common and may be abundant, especially in late spring and summer Domoic acid, a potent neurotoxin, was found at levels up to 154 μg g − 1 wet weight in razor clams, Siliqua patula Dixon, and Dungeness crabs, Cancer magister Dana, on the Pacific coast of Washington in late October 1991. It was also found in trace amounts in blue mussels, Mytilus edulis L., and oysters, Crassostrea gigas Thun., in the inland waters of northern Puget Sound in summer 1992.

Evidence for multiple recruitment-cohorts of Puget Sound Dungeness crab, Cancer magister

While sampling intertidally in Puget Sound, Washington, USA, for juvenile Dungeness crab (Cancer magister) in 1984, we found evidence of two distinct “cohorts” of the same year-class based on sizes of first-instar juveniles (J1) and the spatial/temporal patterns of settlement. In 1988, three distinct cohorts were observed to settle in Puget Sound and its approaches. Settlement of one cohort occurred during May in the Strait of Juan de Fuca and in those areas of Puget Sound closest to the Strait. J1 individuals of this cohort were large (x=7.4 mm carapace width, CW) and comparable in both size and timing of settlement to populations along the Washington coast (e.g. Grays Harbor and Willapa Bay). Initial settlement density of the May cohort was as high as 215 crabs/m2 in intertidal eelgrass beds along the Strait of Juan de Fuca and decreased to <2 crabs/m2 within Puget Sound and the Strait of Georgia. A second cohort apparently originated in Hood Canal (a deep inland fjord), its size upon settlement in June was significantly smaller (J1 x= 5.3 mm CW) than the May cohort, and it was limited to Hood Canal and areas of Puget Sound close to the mouth of Hood Canal. A third cohort, which settled in late July and August, was the smallest of the three cohorts (J1 x= 4.8 mm CW), and was widely distributed around Puget Sound from Seattle in the south to the USA/Canadian border in the north. We hypothesize that most juvenile recruitment in Hood Canal and Puget Sound originates from parental stocks endemic to their respective basins (“Hood Canal” and “Puget Sound” cohorts), but that, on occasion, oceanographic conditions allow substantial influx of Pacific Ocean Dungeness crab larvae (“oceanic” cohort) through the Strait of Juan de Fuca into Puget Sound. Tracking of spatial/temporal settlement patterns and comparison of J1 sizes proved useful for estimating the probable sources and dispersion of Dungeness crab larvae. Differences in size and time of settlement between various larval cohorts of C. magister may prove useful as “biomarkers” for tracing circulation patterns within and between inland waters of Washington and the Pacific Ocean. Causes of smaller size and later settlement of the “Puget Sound” cohort relative to oceanic conspecifics of the same year-class are discussed.

Factors Related to Variability in Feeding Intensity of Juvenile Coho Salmon and Chinook Salmon

Variations in the feeding intensity of juvenile coho salmon Oncorhynchus kisutch and chinook salmon O. tshawytscha collected in coastal waters of Washington and Oregon were examined with respect to year, month, and area of collection and to light intensity, chlorophyll concentration, zooplankton biomass, and salmon abundance measured at the location of capture. Although the absolute amount of food in stomachs increased with increasing predator length, there was not a significant relation between stomach contents (as percent body weight) and predator length for either salmon species. Variations by year and month (but not by area) of collection were significant when examined independently for coho salmon; area (but not year and month) of collection was a significant variable for chinook salmon. Chlorophyll concentration (for coho salmon) and light intensity (for chinook salmon) contributed somewhat to the variability in feeding intensity as determined by a multiple-regression analysis but the abundance of salmon at the location of capture did not. Feeding intensity of juvenile coho salmon was also positively related to the biomass of plankton in surface waters but not to the overall biomass throughout the water column. Feeding success was not adequately described by any one variable examined, apparently because of the interactions among the levels of each variable.

Development of Dispersant Pre-Approval for Washington and Oregon Coastal Waters

ABSTRACT Washington State has initiated the development process for a dispersant pre-approval policy. In order to be more effective under the aegis of the Regional Response Team (RRT), the preapproval policy should, however, cover all of Region X, rather than only a given state within the region. The Region X RRT has, therefore, instigated an environmental impact statement (EIS) for dispersant use in the coastal waters of Washington and Oregon. The objective of this study is to develop recommendations for pre-approval so that a spill response can be immediate and therefore efficient and effective. Preparation of the EIS has been funded by industry through a Clean Sound Cooperative contract to Woodward-Clyde Consultants. The first step in the study is to define those operational factors that limit the areas to be considered. The study then follows the dispersant decision guides summarized by the American Petroleum Institute2 to further define oil types, spill situations and geographical areas where dispersants are a viable option. Finally, there is an analysis of the environmental trade-offs associated with alternative treatment methods and with nontreatment, using the comparative modeling technique developed by S. L. Ross Environmental Research, Ltd. The EIS document will be issued by the Washington Department of Ecology (WDOE) and will focus on areas where dispersant use could be beneficial in terms of ecological trade-offs. Based on the study, a statement from the State of Washington Department of Ecology is anticipated to be promulgated by the end of 1990.

Mortality of harbor seal pups at different sites in the inland waters of Washington.

We examined the mortality rates and causes of death of harbor seal (Phoca vitulina) pups in three regions of the inland waters of Washington (USA) in 1984. One hundred eight pups were collected during 239 searches of the shoreline areas near harbor seal haulout sites or through public reports. Minimum neonatal (up to 1 mo after birth) mortality rates at these regions ranged from 12% to 26% of the pups born. Neonatal mortality was highest in the Strait of Juan de Fuca; 33 of the estimated 105 (31%) pups born at the primary site died. Causes of death varied by location. In southern Puget Sound predation by coyotes (Canis latrans) was the primary cause of death, accounting for eight of 43 (19%) of the dead pups examined; starvation was the next most common cause of death. Mortality at study sites in the Strait of Juan de Fuca was related to premature parturition; 19 of 49 (39%) of the pups found dead were born prematurely. Nine species of bacteria were identified in samples taken from 42 pups; Proteus sp. and Escherichia coli were the most common.

Implementing the U.S.‐CANADA pacific salmon treaty: The struggle to move from “fish wars”; to cooperative fishery management

Abstract On January 28, 1985, the Pacific Salmon Treaty was signed in Ottawa, Canada, culminating 15 years of negotiations to end an increasingly tense “fish war”; between the United States and Canada. The treaty provides a means to manage, conserve, and rebuild stocks of the five species of salmon that inhabit coastal waters of Oregon, Washington, Alaska, and British Columbia Canada. The primary purpose of the treaty is to address equitably the problem of ‘'interceptions''—that is, the harvest of one country's salmon by foreign fishermen. The treaty established the Pacific Salmon Commission as its decision‐making body. To say the Commission's task is difficult is an understatement. Implementing the treaty involves international rules, numerous parties, and several competing interests. The Commission deals with five species of salmon, three major commercial gear groups, and both sport and native American fishermen. In addition, the Commission faces the sensitive task of dealing with four governments (Canada, Alaska, Washington, and Oregon) and various Indian tribes with a treaty right to a share of the harvestable fish passing their traditional fishing grounds. During its first three years of implementing the treaty, the Commission grappled with a number of issues, including those of interpreting treaty ambiguities.

A review of noise effects studies from the U.S. west coast

Concern over the possibility of effects from geophysical activity on marine organisms has recently generated several research studies in California. Results of effects studies by compressed air releases from airguns (seismic energy releases) on fish dispersion and upon physical effects to fish have been obtained. This information includes the physical effects of a simulated, towed geoseismic array on northern anchovy (Engraulis mordax) eggs, larvae, and adults. Other studies have produced data about the schooling behavior of rockfish (Sebastes spp.) exposed to airgun releases. Additional research addressing the effects of seismic energy releases on Dungenesse crab (Cancer magister) eggs and larvae and on rockfish behavior are being planned for the waters of California and Washington.

Incidence of Vibrio cholerae from estuaries of the United States West Coast.

The incidence of Vibrio cholerae in shellfish, sediment, and waters of California, Oregon, and Washington was determined during the summer of 1984. Samples from 24 distinct estuaries were analyzed qualitatively. V. cholerae non-O1 was found in 23 estuaries and in 44.6% of the 529 samples examined. V. cholerae O1 Inaba was isolated from water samples in Morro Bay, Calif. Vibrio mimicus was found in 2.3% of the samples. Cholera enterotoxin was not found in cell-free filtrates of the 100 isolates tested in the Y-1 mouse adrenal cell assay, but heat-labile cytotoxic activity was observed with 3% of the isolates.

Density-Dependent Growth of Age 1 English Sole (Parophrys vetuls) in Oregon and Washington Coastal Waters

We tested whether English sole (Parophrys vetulus) in Oregon and Washington waters show density-dependent growth. We found that there is a significant negative effect of cohort abundance on annual growth rate of age 1 fish, but not on growth of ages 2–7. Unlike most similar studies of density dependence, this result was not confounded by time trends in abundance and growth. The multiple regression of age 1 growth on cohort abundance and temperature accounted for 91% of the interannual variation in growth, which was a significant increase in r2 over that of the previously published relation with temperature alone. However, stock assessments which take into account only the previously published temperature effect on growth for this stock will probably not seriously overestimate the impact of management regulations which increase cohort abundance.

A key to the Mysidacea of the Pacific Northwest

A key to 28 species of Mysidacea of the coastal and inland waters of Oregon, Washington, and British Columbia is presented. The literature on taxonomic revisions, continuing taxonomic problems, and recently described species is reviewed. Diagnostic illustrations and an annotated species list containing the geographic distribution and general ecology of each mysid are also included.