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1.
Proc Natl Acad Sci U S A ; 116(52): 26669-26673, 2019 Dec 26.
Article in English | MEDLINE | ID: mdl-31818941

ABSTRACT

Understanding why females of some mammalian species cease ovulation prior to the end of life is a long-standing interdisciplinary and evolutionary challenge. In humans and some species of toothed whales, females can live for decades after stopping reproduction. This unusual life history trait is thought to have evolved, in part, due to the inclusive fitness benefits that postreproductive females gain by helping kin. In humans, grandmothers gain inclusive fitness benefits by increasing their number of surviving grandoffspring, referred to as the grandmother effect. Among toothed whales, the grandmother effect has not been rigorously tested. Here, we test for the grandmother effect in killer whales, by quantifying grandoffspring survival with living or recently deceased reproductive and postreproductive grandmothers, and show that postreproductive grandmothers provide significant survival benefits to their grandoffspring above that provided by reproductive grandmothers. This provides evidence of the grandmother effect in a nonhuman menopausal species. By stopping reproduction, grandmothers avoid reproductive conflict with their daughters, and offer increased benefits to their grandoffspring. The benefits postreproductive grandmothers provide to their grandoffspring are shown to be most important in difficult times where the salmon abundance is low to moderate. The postreproductive grandmother effect we report, together with the known costs of late-life reproduction in killer whales, can help explain the long postreproductive life spans of resident killer whales.

2.
Mar Mamm Sci ; 37(4): 1428-1453, 2021 Oct.
Article in English | MEDLINE | ID: mdl-34690418

ABSTRACT

Availability of preferred salmonid prey and a sufficiently quiet acoustic environment in which to forage are critical to the survival of resident killer whales (Orcinus orca) in the northeastern Pacific. Although piscivorous killer whales rely on echolocation to locate and track prey, the relationship between echolocation, movement, and prey capture during foraging by wild individuals is poorly understood. We used acoustic biologging tags to relate echolocation behavior to prey pursuit and capture during successful feeding dives by fish-eating killer whales in coastal British Columbia, Canada. The significantly higher incidence and rate of echolocation prior to fish captures compared to afterward confirms its importance in prey detection and tracking. Extremely rapid click sequences (buzzes) were produced before or concurrent with captures of salmon at depths typically exceeding 50 m, and were likely used by killer whales for close-range prey targeting, as in other odontocetes. Distinctive crunching and tearing sounds indicative of prey-handling behavior occurred at relatively shallow depths following fish captures, matching concurrent observations that whales surfaced with fish prior to consumption and often shared prey. Buzzes and prey-handling sounds are potentially useful acoustic signals for estimating foraging efficiency and determining if resident killer whales are meeting their energetic requirements.

4.
J Psychiatr Res ; 176: 58-67, 2024 May 30.
Article in English | MEDLINE | ID: mdl-38843580

ABSTRACT

OBJECTIVE: The Buried in Treasures (BIT) workshop is a promising treatment for hoarding disorder (HD), though many participants struggle with home uncluttering. This randomized waitlist-controlled trial investigated the efficacy of a version of BIT, augmented with in-home uncluttering practice (BIT+). METHOD: Adults (N = 41) with hoarding disorder were recruited from the community and randomly assigned to BIT+ or waitlist. BIT+ consisted of 16 sessions of the BIT workshop and 10 uncluttering home visits over 18 weeks. Outcome measures included the Saving Inventory-Revised (self-report) and the Clutter Image Rating Scale (self and independent evaluator rated). Between group repeated measures analyses using general linear modeling examined the effect of BIT+ vs waitlist control on hoarding symptoms after 18 weeks. Within group analyses examined pre-post effects for all BIT+ participants combined after 18 weeks. RESULTS: After 18 weeks, BIT+ participants benefited significantly more than waitlist controls on hoarding severity with large effect size (Cohen's d = 1.5, p < .001). BIT+ was also associated with improvement reductions in hoarding symptoms, clutter, and functional impairment. CONCLUSIONS: The BIT+ intervention offers promise as a treatment option for hoarding. Adding in-home uncluttering practice may incrementally improve discarding practices. Future controlled trials are warranted.

5.
Behav Ecol ; 34(3): 373-386, 2023.
Article in English | MEDLINE | ID: mdl-37192928

ABSTRACT

In cooperative species, human-induced rapid environmental change may threaten cost-benefit tradeoffs of group behavioral strategies that evolved in past environments. Capacity for behavioral flexibility can increase population viability in novel environments. Whether the partitioning of individual responsibilities within social groups is fixed or flexible across populations is poorly understood, despite its relevance for predicting responses to global change at the population and species levels and designing successful conservation programs. We leveraged bio-logging data from two populations of fish-eating killer whales (Orcinus orca) to quantify patterns of fine-scale foraging movements and their relationships with demography. We reveal striking interpopulation differences in patterns of individual foraging behavior. Females from the endangered Southern Resident (SRKW) population captured less prey and spent less time pursuing prey than SRKW males or Northern Resident (NRKW) females, whereas NRKW females captured more prey than NRKW males. The presence of a calf (≤3 years) reduced the number of prey captured by adult females from both populations, but disproportionately so for SRKW. SRKW adult males with a living mother captured more prey than those whose mother had died, whereas the opposite was true for NRKW adult males. Across populations, males foraged in deeper areas than females, and SRKW captured prey deeper than NRKW. These population-level differences in patterns of individual foraging behavior challenge the existing paradigm that females are the disproportionate foragers in gregarious resident killer whales, and demonstrate considerable variation in the foraging strategies across populations of an apex marine predator experiencing different environmental stressors.

6.
J Psychiatr Res ; 137: 597-602, 2021 05.
Article in English | MEDLINE | ID: mdl-33309063

ABSTRACT

Hoarding disorder (HD), characterized by difficulty parting with possessions and functionally impairing clutter, affects 2-6% of the population. Originally considered part of Obsessive-Compulsive Disorder (OCD), HD became a distinct diagnostic entity in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) in 2013. While sleep impacts OCD, little is known about sleep in HD. As HD patients often report poor sleep in clinical settings, understanding global subjective sleep quality and disturbances may lead to novel therapeutic targets. To address this gap, the authors used a sample of convenience: an existing data set designed to screen research study eligibility and explore the psychopathology and phenomenology of OCD and HD. The data set included information collected from individuals with HD (n = 38), OCD (n = 26), and healthy participants (n = 22) about insomnia, sleep quality, and mood using interviews and structured instruments including the Insomnia Severity Index (ISI), Pittsburgh Sleep Quality Index (PSQI), and Depression Anxiety Stress Scales (DASS). In this data set, HD and OCD groups reported significantly greater insomnia symptoms and poorer sleep quality compared with healthy controls while controlling for depression, age, and gender. A sizable minority of HD and OCD individuals met criteria for comorbid sleep disorders. OCD and HD groups differed in delayed sleep phase prevalence. To our knowledge, this is the first study examining subjective sleep quality and insomnia in HD as compared to healthy individuals and those with OCD, while controlling for relevant clinical characteristics. Given that there are evidence-based treatments for insomnia and other sleep disorders, our study raises the possibility that treatment interventions targeting sleep may improve HD outcomes.


Subject(s)
Hoarding Disorder , Hoarding , Obsessive-Compulsive Disorder , Adult , Diagnostic and Statistical Manual of Mental Disorders , Hoarding Disorder/epidemiology , Humans , Obsessive-Compulsive Disorder/complications , Obsessive-Compulsive Disorder/epidemiology , Prevalence , Sleep
7.
J Psychiatr Res ; 107: 145-150, 2018 12.
Article in English | MEDLINE | ID: mdl-30419524

ABSTRACT

Hoarding disorder is characterized by difficulty parting with possessions and by clutter that impairs the functionality of living spaces. Cognitive behavioral therapy conducted by a therapist (individual or in a group) for hoarding symptoms has shown promise. For those who cannot afford or access the services of a therapist, one alternative is an evidence-based, highly structured, short-term, skills-based group using CBT principles but led by non-professional facilitators (the Buried in Treasures [BIT] Workshop). BIT has achieved improvement rates similar to those of psychologist-led CBT. Regardless of modality, however, clinically relevant symptoms remain after treatment, and new approaches to augment existing treatments are needed. Based on two recent studies - one reporting that personalized care and accountability made treatments more acceptable to individuals with hoarding disorder and another reporting that greater number of home sessions were associated with better clinical outcomes, we tested the feasibility and effectiveness of adding personalized, in-home uncluttering sessions to the final weeks of BIT. Participants (n = 5) had 15 sessions of BIT and up to 20 hours of in-home uncluttering. Reductions in hoarding symptoms, clutter, and impairment of daily activities were observed. Treatment response rate was comparable to rates in other BIT studies, with continued improvement in clutter level after in-home uncluttering sessions. This small study suggests that adding in-home uncluttering sessions to BIT is feasible and effective.


Subject(s)
Hoarding Disorder/therapy , Outcome Assessment, Health Care , Psychotherapy, Group/methods , Activities of Daily Living , Adult , Aged , Feasibility Studies , Female , Humans , Middle Aged , Pilot Projects
8.
Mov Ecol ; 5: 3, 2017.
Article in English | MEDLINE | ID: mdl-28239473

ABSTRACT

BACKGROUND: We sought to quantitatively describe the fine-scale foraging behavior of northern resident killer whales (Orcinus orca), a population of fish-eating killer whales that feeds almost exclusively on Pacific salmon (Oncorhynchus spp.). To reconstruct the underwater movements of these specialist predators, we deployed 34 biologging Dtags on 32 individuals and collected high-resolution, three-dimensional accelerometry and acoustic data. We used the resulting dive paths to compare killer whale foraging behavior to the distributions of different salmonid prey species. Understanding the foraging movements of these threatened predators is important from a conservation standpoint, since prey availability has been identified as a limiting factor in their population dynamics and recovery. RESULTS: Three-dimensional dive tracks indicated that foraging (N = 701) and non-foraging dives (N = 10,618) were kinematically distinct (Wilks' lambda: λ16 = 0.321, P < 0.001). While foraging, killer whales dove deeper, remained submerged longer, swam faster, increased their dive path tortuosity, and rolled their bodies to a greater extent than during other activities. Maximum foraging dive depths reflected the deeper vertical distribution of Chinook (compared to other salmonids) and the tendency of Pacific salmon to evade predators by diving steeply. Kinematic characteristics of prey pursuit by resident killer whales also revealed several other escape strategies employed by salmon attempting to avoid predation, including increased swimming speeds and evasive maneuvering. CONCLUSIONS: High-resolution dive tracks reconstructed using data collected by multi-sensor accelerometer tags found that movements by resident killer whales relate significantly to the vertical distributions and escape responses of their primary prey, Pacific salmon.

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