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Anecdotal and quantitative evidence of the Cougar's (Puma concolor) ability to swim across large bodies of water remains limited in the scientific literature. Here we report a 1.1-km swim by a dispersing male Cougar from the Olympic Peninsula to Squaxin Island in Puget Sound, Washington. We then predict the total number of islands in the Salish Sea that may be accessible to Cougars via swimming, using this Cougar's movement as a potential upper threshold distance, and present sightings records from islands in the Salish Sea to confirm or refute our results. We estimated that 3808 of 6153 islands in the Salish Sea could be accessible to Cougars with ≥1 or more 1.1-km swims, and we confirmed Cougar presence on 18 of those islands. Four islands with confirmed sightings required swims closer to 2 km. Increasing the threshold distance to 2 km yielded an additional 775 potentially accessible islands, including the 4 not captured by the 1.1-km threshold. Cougars are an umbrella species used to identify wildlife corridors across their range. We believe that improving our understanding of Cougar swimming abilities will aid us in determining the extent of habitat connectivity existing in the Pacific Northwest, where current habitat fragmentation characteristic of the Anthropocene may threaten Cougar metapopulation connectivity important to maintaining genetic health of the species. [ABSTRACT FROM AUTHOR]

The inland waters of Washington State are inhabited regularly by 10 species of marine mammals. Updated and comprehensive information regarding marine mammal occurrence, distribution, and behavior in the area is critical when addressing local anthropogenic impact, management, and conservation concerns. We conducted a total of 16,198 km of observation effort during systematic line-transect surveys from a high-wing, twin-engine airplane throughout Puget Sound in all 4 seasons during 2013 to 2016, and in the Strait of Juan de Fuca and San Juan Islands area during summer 2014 and spring 2015. Ten marine mammal species were confirmed across 5772 groups of an estimated 10,673 individuals sighted, including some seasonal patterns of occurrence. The most commonly sighted species in terms of individuals were Harbor Seals (n = 8012), Harbor Porpoises (n = 2168), California Sea Lions (n = 238) and Steller Sea Lions (n = 77). The most common behavior states documented across species among the total 5670 groups were rest (73%) and medium travel (16%); probable foraging was observed among 13 groups (0.2%) and included Gray Whale foraging pits in tidal mudflats. Potential behavioral reactions to the aircraft were rare (0.3% of total individuals), primarily by Harbor Seals and Harbor Porpoises. Results of these surveys represent the most comprehensive up-to-date information available on marine mammal occurrence, distribution, and behavior across seasons in the Puget Sound region. [ABSTRACT FROM AUTHOR]

The Pacific Sand Lance (Ammodytes personatus) is a major component of the forage base for many species of marine birds, mammals, and fishes. Despite its ecological importance, relatively little is known regarding basic biology or life-history parameters for this species. Information on age and growth is particularly lacking for Pacific Sand Lance in the Salish Sea, an inland sea that encompasses the San Juan Archipelago in Washington State. Here, we present information on age and growth of Pacific Sand Lance from this region and then contrast it with a previous study based in Cook Inlet, Alaska. These 2 regions comprise the latitudinal extremes of the Gulf of Alaska large marine ecosystem. We found evidence for possible differences in growth of Pacific Sand Lance between the 2 regions, with San Juan Island fish generally being smaller at age than fish in Cook Inlet. We interpret these results with respect to regional and temporal differences in environmental conditions and resource availability linked to duration and magnitude of seasonal production, which we hypothesize affects the period of winter dormancy employed by this species as a strategy to cope with resource limitation. [ABSTRACT FROM AUTHOR]

After initial colonization of the Strait of Georgia in the late 19th and early 20th centuries, nesting populations and number of colonies of Pelagic Cormorant (Phalacrocorax pelagicus) and Double-crested Cormorant (P. auritus) increased in abundance until 1987, but subsequently both species declined by 2000. To update population status, we conducted surveys of 45 Pelagic Cormorant and 24 Double-crested Cormorant nesting colonies in 2014, and supplemented this survey with recent and historic counts conducted from 1955 to 2015. We modeled changes in population size over 6 decades to measure long-term population changes, and found strong nonlinear trends that varied widely among colonies. Using years when all known colonies in the Strait of Georgia were surveyed, we documented that the Pelagic Cormorant population increased from 961 to 2234 nests in 1959-1974, remained fairly stable (approximately 2250-2450 nests) from 1974 to 1987, decreased after 1987 to approximately 1100 nests in 2000, and then rose slightly to approximately 1400 nests in 2014. The Double-crested Cormorant population increased from approximately 250 nests from 1959-1960, to approximately 1900 nests in 1987, before decreasing to approximately 600 nests in 2000, and remaining at this level through 2014. Many smaller colonies of both cormorant species no longer exist, and the majority of Pelagic and Double-crested Cormorants currently nest on Mandarte Island, Mitlenatch Island, and 3 bridge locations (Second Narrows, and Burrard & Granville) in Vancouver. The main factors apparently causing decline after 1987 are increased predation and disturbance by Bald Eagles (Haliaeetus leucocephnlus), a potential reduction in availability of forage-fish prey, and human disturbance. Remaining large colonies offer some protection from eagle impacts (cliff habitats or man-made structures) or alternate avian prey for Bald Eagles, such as Glaucous-winged Gulls (larus glaucesems) at Mandarte and Mitlenatch islands. In 2013-2015, small numbers of Brandt's Cormorants (P. penicillatus) nested at Mandarte Island. Continued monitoring is needed to track changes in populations and nesting locations and to inform management of cormorants in the Strait of Georgia. [ABSTRACT FROM AUTHOR]

Breeding within the Salish Sea by Pelagic Cormorant ( Phalacrocorax pelagicus), Double-crested Cormorant ( P. auritus) and Brandt's Cormorant ( P. penicillatus) was summarized from published and unpublished sources for the 1891-1955 period. None of the 3 cormorant species were recorded breeding in the Salish Sea between 1792 and 1891 although sporadic breeding may have been missed. Pelagic Cormorants were first reported breeding at Mandarte Island, British Columbia, in 1891 and afterwards bred there regularly; by 1955, 22 colonies had formed in the central and northern Salish Sea, including the San Juan Islands ( n = 9), Gulf Islands ( n = 5), inner Strait of Juan de Fuca ( n = 4), and northern Strait of Georgia ( n = 4). Before regular breeding by Double-crested Cormorants began at Mandarte Island (1927) and Ballingall Islets (1934), they apparently bred sporadically at St. John's Point (Hornby Island) in the northern Salish Sea (1896) and Mandarte Island (1900). By 1955, 8 colonies had formed in the central and northern Salish Sea, including the San Juan Islands ( n = 3), Gulf Islands ( n = 3) and northern Strait of Georgia ( n = 2). Brandt's Cormorants only bred sporadically in the San Juan Islands at Flattop Island (1928), Matia Island (1940) and Lopez Island (<1953). Evidence of breeding in the central Salish Sea by all 3 cormorant species suggested resettlement of individuals from colonies on the outer west coast of Washington through the Strait of Juan de Fuca. Subsequent expansion by Pelagic and Double-crested cormorants in the central and northern Salish Sea suggested local growth after colonization, although impacts from human disturbance and predators affected certain colonies. Reduced harvesting by the shrinking population of indigenous peoples at cormorant colonies on the outer coast of Washington likely prompted colonization of the Salish Sea. [ABSTRACT FROM AUTHOR]

Central questions of ecology concern how and why organisms distribute themselves in time and space. Answers to these questions contribute to our understanding of the fitness of organisms and provide baseline information against which to compare future distributions in the face of environmental change. Here we characterize daily and yearly fluctuations in counts of Glaucous-winged Gulls ( Larus glaucescens) in 5 connected habitats associated with a large seabird colony in the Salish Sea, Washington State. Daily fluctuations in the 5 habitats differed markedly and were driven by day of year, time of day, solar elevation, tide height, barometric pressure, and ambient temperature. Seasonal peak numbers in all habitats occurred between mid-March and mid-September. No gulls remained on their breeding territories past late September, and few gulls remained on the island between late September and mid-January. Numbers rose steadily from early February to March. [ABSTRACT FROM AUTHOR]

Collecting long-term population trend data on indicator species contributes to our understanding of overall ecosystem health. The Pigeon Guillemot, a burrow-nesting piscivore, was identified as one of many indicators of health in Puget Sound, Washington. We observed the local guillemot population size, burrow occupancy, chick diet composition (identified as single fish carried in adult bills), and prey delivery rates to chicks on Whidbey Island, WA, between 2009 and 2014. Observations were conducted by trained volunteers from the Whidbey Audubon Society and the former Island County Beach Watchers (now Sound Water Stewards) who counted adults, verified burrow occupancy, and recorded prey delivery frequency and composition. Using the maximum counts across all Whidbey Island colonies, the index of abundance observed annually was an average of 991 individuals. A mean of 240 occupied burrows were observed each year. The peak rate of prey delivery occurred between the weeks of 12 July and 2 August, annually. Types of delivered prey consisted of 57.6% gunnel or prickleback (Pholidae or Stichaeidae), 25.6% sculpin (Cottidae), and 16.5% other or unknown prey. These data serve as a diet and reproductive baseline for assessing changes over time. [ABSTRACT FROM AUTHOR]

Pacific Sand Lance ( Ammodytes personatus) are energy-rich schooling fish that are thought to be important drivers of marine food webs in Alaska (USA) and British Columbia (Canada). Despite a number of studies characterizing their distribution and habitat use in Alaska and British Columbia, surprisingly little is known about population attributes in the Salish Sea. We compiled and analyzed 15,192 records collected from 1630 sites, primarily by beach seine or tow net in nearshore shallow areas between 1970 and 2009, to determine Sand Lance spatial and seasonal distribution in the inland waters of Washington State. Sand Lance were present along 78% of the shoreline that was sampled and were captured during every month of the year. The maximum number captured in individual nets increased between May and August. Fork length ranged from 1.7 to 19.0 cm and average fork length did not vary by month. The shortest minimum fork lengths were documented during April through July, likely representing annual recruits, but size at maturity is not known for the local population. Their widespread distribution throughout the region and peak abundance during summer suggests that they are an important potential prey source and could be a driver of marine food webs in this region. [ABSTRACT FROM AUTHOR]

A single incident of attempted predation of a Harbor Seal ( Phoca vitulina) pup by an American Mink ( Neovision vision) was observed on Blakely Island, Washington in 2015. San Juan County Marine Mammal Stranding Network members responded, investigated the event, and performed a necropsy on the seal. Predation is the most parsimonious explanation for the attack due to the American Mink's opportunistic predatory tendencies and the vulnerability of the moribund Harbor Seal. With both the American Mink and Harbor Seal populations documented as abundant or at carrying capacity, respectively, mink predation on vulnerable Harbor Seal pups could increase or influence Harbor Seal haul-out behavior. [ABSTRACT FROM AUTHOR]

Efforts are underway to restore the Salish Sea, a 16,925 km2 inland sea shared by Washington State, USA, and British Columbia, Canada. A list of the birds and mammals that use this marine ecosystem is lacking. We compiled information from varied sources and identified 172 bird and 37 mammal species that depend on the Salish Sea marine ecosystem. Of these species, 72 bird and 29 mammal species are both highly dependent on intertidal or marine habitat as well as on marine derived food. One hundred bird species and 8 mammal species that use the Salish Sea marine ecosystem have varying degrees of dependence on the marine and terrestrial ecosystems to meet significant life history needs. These interactions between the marine and terrestrial ecosystems indicate the need to integrate marine and terrestrial restoration efforts to achieve long-term conservation of the suite of birds and mammals that use and depend on the marine ecosystem. This comprehensive list of avian and mammal fauna for the Salish Sea serves as a foundation for determining the occurrence of new species and the disappearance of others, enables selection of species as indicators for ecosystem health, and also provides a basis for identifying the mechanisms responsible for marine bird and mammal declines. [ABSTRACT FROM AUTHOR]

The Harbor Porpoise normally occurs in groups of 2 to 5 individuals. We report a sighting of 74 Harbor Porpoises near the entrance to Vancouver Harbor, Canada. When corrected for detection underestimate, this group was possibly as numerous as 1894 individuals, which we call a super pod [ABSTRACT FROM AUTHOR]