Remembering Paul Johnsgard

Paul A. Johnsgard (1931–2021) was a friend of many, an artist, prolific author, teacher, and humble admirer of all living creatures. It was impossible to find someone at Nebraska Audubon Society or Nebraska Ornithologists’ Union meetings who did not know Paul Johnsgard. His more than 100 published books made him known not just in a community of ornithologists, birdwatchers, and bird lovers in the United States but also abroad. He was a world-renowned ornithologist and naturalist who remained deeply embedded in his local culture and its prairie environment. We invited about 75 people to write a short memory of Paul. We received about 40 responses, which are published in this book, along with Paul Johnsgard’s own writing on his life. Contributors to this volume include George Archibald, Cherrie Beam-Callaway, Jo D Blessing, Charles Brown, Linda Brown, Jackie Canterbury, John Carlini, Ron Cisar, David Duey, Richard Edwards, Michael Forsberg, Karine Gil, Sue Guild, Twyla Hansen, Chris Helzer, John Janovy, Allison Johnson, Michelle Johnson, Joel Jorgensen, Fujiyo Koizumi, Josef Kren, Thomas Labedz, Kam-Ching Leung, Thomas Mangelsen, Martin Massengale, Julie Masters, Marilyn McNabb, W. Don Nelson, Neal Ratzlaff, Arlys Reitan, James Rosowski, Paul Royster, William Scharf, Rachel Simpson, Tiffany Talbot, Rick Wright, and Christy Yuncker Happ. Cover: Paul Johnsgard at Cedar Point Biological Station, July 2006. Photo by Linda Brown With 60 color photographs ISBN 978-1-60962-289-3 ebook doi: 10.32873/unl.dc.zea.1500https://digitalcommons.unl.edu/zeabook/1142/thumbnail.jp

Increased risk of depression in non-depressed HIV infected men with sleep disturbance: Prospective findings from the Multicenter AIDS Cohort Study.

ObjectiveSleep disturbance is a known risk factor for depression, but it is not known whether sleep disturbance contributes to greater risk of depression in those infected with human immunodeficiency virus (HIV+) as compared to those uninfected with HIV (HIV-).MethodsUsing data from the Multicenter AIDS Cohort Study, a population-based prospective study of men who have sex with men (MSM), self-reported sleep disturbance (>2 weeks) and depressive symptoms (Clinical Epidemiologic Scale for Depression, CES-D) were assessed every 6 months over 12 years of follow-up. Adjusted mixed effects logistic regression analyses tested whether sleep disturbance predicted depression (CES-D ≥ 16) at the immediate subsequent visit, and so on over 12 years, in non-depressed HIV+(N = 1054; 9556 person-visits) and non-depressed HIV- (N = 1217; 12,680 person-visits). In HIV+ vs. HIV- MSM, linearly estimated average incidence of depression and normalized cumulative rate of depression over 12 years were compared.ResultsIn the HIV+ MSM, sleep disturbance was associated with a significant increase in depression 6 months later (OR = 1.6; 95% CI, 1.30, 1.96), which was significantly greater (P < .05) than in HIV- MSM (OR = 1.16; 95% CI, 0.94, 1.44). HIV status and sleep disturbance interacted (P < .001), such that incidence of depression and normalized cumulative rate of depression were greater in HIV+ with sleep disturbance than in HIV+ without sleep disturbance and HIV- groups (all P's < 0.001).ConclusionsHIV+ persons who report sleep disturbance represent a high risk group to be monitored for depression, and possibly targeted for insomnia treatment to prevent depression. FUND: National Institute of Allergy and Infectious Diseases

America is not losing its religion – population trends mean thatit is simply becoming more religiously diverse.

A recent Pew study found that there has been an increase in the number of Americans who claim to have ‘no-religion’. Does this mean that religion in the U.S. is on the way out? In new research which examines data from three national surveys, R. Khari Brown, Robert Joseph Taylor, and Linda M. Chatters find that African Americans and African Caribbean Americans are less likely than Non-Hispanic Whites, Hispanic Americans, and Asian Americans to identify as non-religious, with the latter group the most likely to identify as non-religious. They write that the recent shifts in religious affiliation may have less to do with Americans abandoning religion to America shifting towards increasing religious diversity

Testosterone and Group Size in Cliff Swallows: Testing the “Challenge Hypothesis” in a Colonial Bird

The “challenge hypothesis” states that increases in testosterone levels of male animals during the breeding season are directly related to the extent of intrasexual competition for resources or mates that they experience. Although often tested in territorial species, the challenge hypothesis has not been evaluated for colonial animals that live in groups of different sizes and that thus experience different intensities of intrasexual competition. We measured circulating testosterone levels of male and female cliff swallows (Petrochelidon pyrrhonota) in southwestern Nebraska, where these birds nest in colonies of widely different sizes. Males had significantly higher testosterone levels than females, as expected. For males especially, there was a seasonal rise in testosterone levels early in the nesting cycle, corresponding to the period when birds were establishing nest ownership and egg laying, and then a fall as they switched to parental duties. Testosterone levels varied significantly with colony size; for both sexes, birds in larger colonies had higher levels of testosterone than those in smaller colonies when controlling for date. Age and body mass were not related to testosterone levels. Higher levels of testosterone for birds of both sexes in larger colonies probably reflect greater com-petition for matings, often extra pair, in the more social nesting situations. The results support the predictions of the challenge hypothesis

Testosterone and Group Size in Cliff Swallows: Testing the “Challenge Hypothesis” in a Colonial Bird

The “challenge hypothesis” states that increases in testosterone levels of male animals during the breeding season are directly related to the extent of intrasexual competition for resources or mates that they experience. Although often tested in territorial species, the challenge hypothesis has not been evaluated for colonial animals that live in groups of different sizes and that thus experience different intensities of intrasexual competition. We measured circulating testosterone levels of male and female cliff swallows (Petrochelidon pyrrhonota) in southwestern Nebraska, where these birds nest in colonies of widely different sizes. Males had significantly higher testosterone levels than females, as expected. For males especially, there was a seasonal rise in testosterone levels early in the nesting cycle, corresponding to the period when birds were establishing nest ownership and egg laying, and then a fall as they switched to parental duties. Testosterone levels varied significantly with colony size; for both sexes, birds in larger colonies had higher levels of testosterone than those in smaller colonies when controlling for date. Age and body mass were not related to testosterone levels. Higher levels of testosterone for birds of both sexes in larger colonies probably reflect greater com-petition for matings, often extra pair, in the more social nesting situations. The results support the predictions of the challenge hypothesis

Effects of Endogenous Steroid Hormone Levels on Annual Survival in Cliff Swallows

The hormone corticosterone is an important part of animals’ response to environmental stress, modulating short-term adaptive changes in behavior and physiology. The hormone testosterone is also critical, especially for males, in regulating the expression of sexual behavior and parental care. These hormones can have costly consequences, however, and within populations individuals show variation in endogenous levels of both corticosterone and testosterone. We studied how annual survival varied as a function of natural levels of these hormones in colonially breeding Cliff swallows (Petrochelidon pyrrhonota) in southwestern Nebraska, USA, in 2000–2003. We sampled hormone levels of birds caught at colonies and using mark–recapture, monitored their survival through subsequent years in the study area. Maximum-likelihood estimation and model fitting (with program MARK) revealed that birds sampled for corticosterone in colonies of all sizes late in the season had curvilinear survival; individuals with very low and very high levels of corticosterone had lower survival than those with intermediate levels. Annual survival of birds sampled earlier in the season, however, generally declined with increasing corticosterone level. More birds than expected, given the survival functions, had the very low corticosterone levels in nonfumigated colonies later in the year, suggesting perhaps a compensatory benefit unrelated to survival for very low corticosterone levels. In a more limited analysis, testosterone appeared to have little effect on annual survival, although some evidence suggested that females with endogenous testosterone levels below the mean for a given date might have survived better

Glucocorticoid Hormone Levels Increase with Group Size and Parasite Load in Cliff Swallows

Animals often cope with adverse events by releasing glucocorticoid hormones, which in turn promote increased energy assimilation. In captive animals, crowding also leads to increased glucocorticoid activity, probably because of increased levels of social competition. We investigated how group size and ectoparasite infestations affected endogenous levels of the glucocorticoid hormone, corticosterone, in colonial cliff swallows, Petrochelidon pyrrhonota, in southwestern Nebraska, USA. Parasites were removed from some colonies by fumigating nests. Baseline levels of corticosterone in breeding adults varied significantly with whether parasites were present, colony size (measured by total number of active nests at a site), and nesting stage. Across all analyses, birds from fumigated colonies averaged significantly lower baseline levels of corticosterone. These levels in adults increased with colony size at nonfumigated sites, especially during the period when nestlings were being fed, but no relation or the opposite one was found for birds in fumigated colonies. Baseline corticosterone levels were unrelated to sex, age, body weight, or testosterone levels in adults. Corticosterone concentrations tended to increase during a bad-weather event when food was scarce. Patterns in nestling and recently fledged juveniles were consistent with those in adults. The increased baseline levels of corticosterone in birds of larger colonies appear related to the larger number of parasites there. Higher levels of corticosterone probably facilitate increased allocation of time and energy to foraging and greater energy assimilation during challenging events such as bad weather, parasitism by blood-feeding bugs in large colonies, and the period when young are becoming independent of their parents

Effects of Endogenous Steroid Hormone Levels on Annual Survival in Cliff Swallows

The hormone corticosterone is an important part of animals’ response to environmental stress, modulating short-term adaptive changes in behavior and physiology. The hormone testosterone is also critical, especially for males, in regulating the expression of sexual behavior and parental care. These hormones can have costly consequences, however, and within populations individuals show variation in endogenous levels of both corticosterone and testosterone. We studied how annual survival varied as a function of natural levels of these hormones in colonially breeding Cliff swallows (Petrochelidon pyrrhonota) in southwestern Nebraska, USA, in 2000–2003. We sampled hormone levels of birds caught at colonies and using mark–recapture, monitored their survival through subsequent years in the study area. Maximum-likelihood estimation and model fitting (with program MARK) revealed that birds sampled for corticosterone in colonies of all sizes late in the season had curvilinear survival; individuals with very low and very high levels of corticosterone had lower survival than those with intermediate levels. Annual survival of birds sampled earlier in the season, however, generally declined with increasing corticosterone level. More birds than expected, given the survival functions, had the very low corticosterone levels in nonfumigated colonies later in the year, suggesting perhaps a compensatory benefit unrelated to survival for very low corticosterone levels. In a more limited analysis, testosterone appeared to have little effect on annual survival, although some evidence suggested that females with endogenous testosterone levels below the mean for a given date might have survived better