Fine-Scale Variability in Harbor Seal Foraging Behavior

Understanding the variability of foraging behavior within a population of predators is important for determining their role in the ecosystem and how they may respond to future ecosystem changes. However, such variability has seldom been studied in harbor seals on a fine spatial scale (km). We used a combination of standard and Bayesian generalized linear mixed models to explore how environmental variables influenced the dive behavior of harbor seals. Time-depth recorders were deployed on harbor seals from two haul-out sites in the Salish Sea in 2007 (n = 18) and 2008 (n = 11). Three behavioral bout types were classified from six dive types within each bout; however, one of these bout types was related to haul-out activity and was excluded from analyses. Deep foraging bouts (Type I) were the predominant type used throughout the study; however, variation in the use of bout types was observed relative to haul-out site, season, sex, and light (day/night). The proportional use of Type I and Type II (shallow foraging/traveling) bouts differed dramatically between haul-out sites, seasons, sexes, and whether it was day or night; individual variability between seals also contributed to the observed differences. We hypothesize that this variation in dive behavior was related to habitat or prey specialization by seals from different haul-out sites, or individual variability between seals in the study area. The results highlight the potential influence of habitat and specialization on the foraging behavior of harbor seals, and may help explain the variability in diet that is observed between different haul-out site groups in this population

Control of California sea lion predation of winter-run steelhead at the Hiram M. Chittenden Locks, Seattle, December 1985-April 1986 with observations on sea lion abundance and distribution in Puget Sound

A study/predation control program was conducted at the Hiram M. Chittenden Locks in Seattle, Washington from 20 December through 23 April 1986. The principal objectives were to document the rate and effects of predation on winter-run steelhead (Salmo gairdneri Richardson) by California sea lions (Zalophus californianus); to control and minimize predation in order to increase the escapement of wild winter-runs to the Lake Washington watershed; to evaluate and recommend potential long term procedures for control of steelhead predation; and to document the abundance and distribution of California sea lions in Puget Sound

Developmental Trajectories and Reference Percentiles for the 6-Minute Walk Test for Children With Cerebral Palsy.

PURPOSE: The purposes of this study were to document longitudinal developmental trajectories in 6-minute walk test (6MWT) distances and to develop age-specific reference percentiles for children across different Gross Motor Function Classification System (GMFCS) levels. METHODS: A TOTAL OF: 456 children with cerebral palsy ages 3 to 12 years of, GMFCS levels I to III participated. Children\u27s motor function was classified on the GMFCS, and children completed the 6MWT 2 to 5 times in 2 years. RESULTS: Longitudinal developmental trajectories support that 6MWT distances increase with age followed by a tapering, as children approach their functional limit relative to their GMFCS level. Reference percentile graphs were created to monitor change over time. CONCLUSIONS: The 6MWT longitudinal developmental trajectories, reference percentiles, and interpretation of percentile change should assist collaborative and proactive intervention planning relative to functional walking capacity for children with cerebral palsy

PCB-Related Alteration of Thyroid Hormones and Thyroid Hormone Receptor Gene Expression in Free-Ranging Harbor Seals (Phoca vitulina)

Persistent organic pollutants are environmental contaminants that, because of their lipophilic properties and long half-lives, bioaccumulate within aquatic food webs and often reach high concentrations in marine mammals, such as harbor seals (Phoca vitulina). Exposure to these contaminants has been associated with developmental abnormalities, immunotoxicity, and reproductive impairment in marine mammals and other high-trophic-level wildlife, mediated via a disruption of endocrine processes. The highly conserved thyroid hormones (THs) represent one vulnerable endocrine end point that is critical for metabolism, growth, and development in vertebrates. We characterized the relationship between contaminants and specific TH receptor (TR ) gene expression in skin/blubber biopsy samples, as well as serum THs, from free-ranging harbor seal pups (n = 39) in British Columbia, Canada, and Washington State, USA. We observed a contaminant-related increase in blubber TR-α gene expression [total polychlorinated biphenyls (∑PCBs); r = 0.679; p < 0.001] and a concomitant decrease in circulating total thyroxine concentrations (∑PCBs; r = −0.711; p < 0.001). Consistent with results observed in carefully controlled laboratory and captive feeding studies, our findings suggest that the TH system in harbor seals is highly sensitive to disruption by environmental contaminants. Such a disruption not only may lead to adverse effects on growth and development but also could have important ramifications for lipid metabolism and energetics in marine mammals

Developmental Trajectories and Reference Percentiles for Range of Motion, Endurance, and Muscle Strength of Children With Cerebral Palsy.

BACKGROUND: Children with cerebral palsy (CP) frequently present with secondary impairments in spinal alignment and extremity range of motion, endurance for activity, and muscle strength. Creation of developmental trajectories for these impairments will help guide clinical decision-making. OBJECTIVE: For children in each level of the Gross Motor Function Classification System (GMFCS) this study aimed to: (1) create longitudinal developmental trajectories for range of motion (Spinal Alignment and Range of Motion Measures [SAROMM]), endurance (Early Activity Scale for Endurance [EASE]), and functional strength (Functional Strength Assessment [FSA]); and (2) develop age-specific reference percentiles and amount of change typical over 1 year for these outcomes. DESIGN: This study used a longitudinal cohort design. METHODS: Participants comprised 708 children with CP across GMFCS levels, aged 18 months up to the 12th birthday, and their families. In 2 to 5 assessments every 6 months over 2 years, trained therapists performed the SAROMM and FSA, and parents completed the EASE questionnaire. For children in each GMFCS level, longitudinal trajectories using linear and nonlinear mixed-effects models from all visits, and reference percentiles using quantile regression from the first, 12-month, and 24-month visits were created for each measure. RESULTS: Longitudinal trajectories and percentile graphs for SAROMM, FSA, and EASE were primarily linear, with different performance scores among GMFCS levels. There was much variability in both longitudinal trajectories and percentiles within GMFCS levels. LIMITATIONS: Limitations included a convenience sample and varying numbers of participants assessed at each visit. CONCLUSIONS: The longitudinal trajectories and percentile graphs have application for monitoring how children with CP are performing and changing over time compared with other children with CP. The resources presented allow therapists and families to collaboratively make decisions about intervention activities targeted to children\u27s unique needs

Longitudinal trajectories and reference centiles for the impact of health conditions on daily activities of children with cerebral palsy.

AIM: First, to describe the impact of health conditions on daily activities over time in children with cerebral palsy (CP) and to create age-specific reference centiles. Second, to determine the amount of change typical over a 1-year period, across Gross Motor Function Classification System (GMFCS) levels. METHOD: A prospective, cohort design, with five assessments over 2 years, involved 708 children with a confirmed diagnosis of CP participating in the On Track Study (396 males, 312 females; mean age 6y [SD 2y 7mo]; range 18mo-12y at first assessment; 32.1% in GMFCS level I, 22.7% in GMFCS level II, 11.2% in GMFCS level III, 18.2% in GMFCS level IV, 15.7% in GMFCS level V). The impact of health conditions on daily activities was assessed using the Child Health Conditions Questionnaire. Data were analyzed using mixed-effects models and quantile regression. RESULTS: Linear longitudinal trajectories describe the relatively stable impact of health conditions over time for each functional level for children aged 2 years to 12 years, with the lowest scores (least impact) in GMFCS level I and the highest scores (highest impact) in GMFCS level V. Centiles were created for children in each GMFCS level. A system to interpret the magnitude of change over time in centiles was developed. INTERPRETATION: Longitudinal trajectories of co-occurring health conditions assist with understanding children\u27s prognoses. Centiles assist in understanding a child\u27s experience relative to children in similar GMFCS levels. Guidelines are provided to determine if children are progressing \u27as expected\u27, \u27better than expected\u27 or \u27more poorly than expected\u27 in regard to the impact of health conditions on daily activities. WHAT THIS PAPER ADDS: For children with cerebral palsy, the mean impact of health conditions on daily activities is relatively stable. Significant intraindividual and interindividual variability for the impact of health conditions exists, which complicates prognosis. Centiles enable interpretation of the impact of health conditions relative to Gross Motor Function Classification System level

Three new species of Dolichogenidea Viereck (Hymenoptera, Braconidae, Microgastrinae) from Australia with exceptionally long ovipositors

The subfamily Microgastrinae contains an extraordinarily rich diversity of parasitoid wasps which parasitise larval lepidopterans. The Australian fauna has generally been poorly studied, particularly for the very speciose genera. One such genus is Dolichogenidea Vierek, which in Australia is known from only six described species. Here we describe three new species of Dolichogenidea from Australia, which are distinguished by possessing extremely long ovipositors compared with the typical form for the genus. These are D. finchi Fagan-Jeffries &amp;amp; Austin, sp. n., D. mediocaudata Fagan-Jeffries &amp;amp; Austin, sp. n., and D. xenomorph Fagan-Jeffries &amp;amp; Austin, sp. n. In describing these new species we also discuss relationships within the genus, and the diversity and biology of the Australian fauna

Long Distance Movements and Disjunct Spatial Use of Harbor Seals (Phoca Vitulina) in the Inland Waters of the Pacific Northwest

Background Worldwide, adult harbor seals (Phoca vitulina) typically limit their movements and activity toresult, the ecological impact of harbor seals is viewed as limited to relatively small spatial scales. Harbor seals in the Pacific Northwest are believed to remainsite, one of several contributing factors to the current stock designation. However, movement patterns within the region are not well understood because previous studies have used radio-telemetry, which has range limitations. Our objective was to use satellite-telemetry to determine the regional spatial scale of movements. Methodology Satellite tags were deployed on 20 adult seals (n=16 males and 4 females) from two rocky reefs and a mudflat-bay during April–May 2007. Standard filtering algorithms were used to remove outliers, resulting in an average (± SD) of 693 (±377) locations per seal over 110 (±32) days. A particle filter was implemented to interpolate locations temporally and decrease erroneous locations on land. Minimum over-water distances were calculated between filtered locations and each seal\u27s capture site to show movement of seals over time relative to their capture site, and we estimated utilization distributions from kernel density analysis to reflect spatial use. Eight males moved \u3e100 km from their capture site at least once, two of which traveled round trip to and from the Pacific coast, a total distance \u3e400 km. Disjunct spatial use patterns observed provide new insight into general harbor seal behavior. Conclusions/Significance Long-distance movements and disjunct spatial use of adult harbor seals have not been reported for the study region and are rare worldwide in such a large proportion of tagged individuals. Thus, the ecological influence of individual seals may reach farther than previously assumed

Fish consumption by harbor seals (Phoca vitulina) in the San Juan Islands, Washington

The harbor seal (Phoca vitulina) is a large-bodied and abundant predator in the Salish Sea ecosystem, and its population has recovered since the 1970s after passage of the Marine Mammal Protection Act and the cessation of bounties. Little is known about how this large predator population may affect the recovery of fish stocks in the Salish Sea, where candidate marine protected areas are being proposed. We used a bioenergetics model to calculate baseline consumption rates in the San Juan Islands, Washington. Salmonids (Oncorhynchus spp.) and herring (Clupeidae) were the 2 most energetically important prey groups for biomass consumed by harbor seals. Estimated consumption of salmonids was 783 (±380 standard deviation [SD]) metric tons (t) in the breeding season and 675 (±388 SD t in the nonbreeding season. Estimated consumption of herring was 646 (±303 SD) t in the breeding season and 2151 (±706 SD) t in the nonbreeding season. Rockfish, a depressed fish stock currently in need of population recovery, composed one of the minor prey groups consumed by harbor seals (84 [±26 SD] t in the nonbreeding season). The variables of seal body mass and proportion of prey in seal diet explained >80% of the total variation in model outputs. Prey groups, such as rockfish, that are targeted for recovery may still be affected by even low levels of predation. This study highlights the importance of salmonids and herring for the seal population and provides a framework for refining consumption estimates and their confidence intervals with future data