1
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Delaitre S, Visser ME, van Oers K, Caro SP. Odours of caterpillar-infested trees increase testosterone concentrations in male great tits. Horm Behav 2024; 160:105491. [PMID: 38340412 DOI: 10.1016/j.yhbeh.2024.105491] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2023] [Revised: 12/22/2023] [Accepted: 01/21/2024] [Indexed: 02/12/2024]
Abstract
Trees release Herbivore-Induced Plant Volatiles (HIPVs) into the air in response to damage inflicted by insects. It is known that songbirds use those compounds to locate their prey, but more recently the idea emerged that songbirds could also use those odours as cues in their reproductive decisions, as early spring HIPVs may contain information about the seasonal timing and abundance of insects. We exposed pre-breeding great tits (Parus major) to the odours of caterpillar-infested trees under controlled conditions, and monitored reproduction (timing of egg laying, number of eggs, egg size) and two of its main hormonal drivers (testosterone and 17β-estradiol in males and females, respectively). We found that females exposed to HIPVs did not advance their laying dates, nor laid larger clutches, or larger eggs compared to control females. 17β-estradiol concentrations in females were also similar between experimental and control birds. However, males exposed to HIPVs had higher testosterone concentrations during the egg-laying period. Our study supports the hypothesis that insectivorous songbirds are able to detect minute amounts of plant odours. The sole manipulation of plant scents was not sufficient to lure females into a higher reproductive investment, but males increased their reproductive effort in response to a novel source of information for seasonal breeding birds.
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Affiliation(s)
| | - Marcel E Visser
- Department of Animal Ecology, Netherlands Institute of Ecology (NIOO-KNAW), P.O. Box 50, 6700 AB Wageningen, the Netherlands
| | - Kees van Oers
- Department of Animal Ecology, Netherlands Institute of Ecology (NIOO-KNAW), P.O. Box 50, 6700 AB Wageningen, the Netherlands
| | - Samuel P Caro
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, Montpellier, France.
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2
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Snell CL, Reudink MW, Otter KA. Hard of hearing: the effect of distance and experimental noise on mountain chickadee song transmission. BIOACOUSTICS 2023. [DOI: 10.1080/09524622.2023.2172080] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/11/2023]
Affiliation(s)
- C. L. Snell
- Natural Resources and Environmental Studies, University of Northern British Columbia, Prince George, BC, Canada
| | - M. W. Reudink
- Department of Biological Sciences, Thompson Rivers University, Kamloops, BC, Canada
| | - K. A. Otter
- Natural Resources and Environmental Studies, University of Northern British Columbia, Prince George, BC, Canada
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3
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Drones and sound recorders increase the number of bird species identified: A combined surveys approach. ECOL INFORM 2023. [DOI: 10.1016/j.ecoinf.2023.101988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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4
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Norris AR, Martin K, Cockle KL. Weather and nest cavity characteristics influence fecundity in mountain chickadees. PeerJ 2022; 10:e14327. [PMID: 36389406 PMCID: PMC9661973 DOI: 10.7717/peerj.14327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Accepted: 10/11/2022] [Indexed: 11/13/2022] Open
Abstract
Background Examining direct and indirect effects on reproduction at multiple scales allows for a broad understanding of species' resilience to environmental change. We examine how the fecundity of the mountain chickadee (Poecile gambeli), a secondary cavity-nesting, insectivorous bird, varied in relation to factors at three scales: regional weather conditions, regional- and site-level food availability, site-level community dynamics, and nest-level cavity characteristics. We hypothesized that earlier laying dates and higher fecundity (clutch size, nest survival, brood size) would be associated with milder climatic conditions, increased food from insect outbreaks, lower densities of conspecifics and nest predators (red squirrel; Tamiasciurus hudsonicus), and safer (smaller, higher) cavities. Methods We collected data on laying date, clutch size, brood size, nest fate (success/failure), and cavity characteristics from 513 mountain chickadee nests in tree cavities in temperate mixed coniferous-broadleaf forest in interior British Columbia, Canada, from 2000 to 2011. We surveyed annual abundances of mountain chickadees and squirrels using repeated point counts, and mountain pine beetle (Dendroctonus ponderosae) and lepidopteran defoliators by monitoring host trees and by using regional-scale aerial overview forest insect survey data. We used weather data (temperature, rain, snow) from a local Environment and Climate Change Canada weather station. We modeled laying date, clutch size, daily nest survival, and brood size as a function of predictors at regional-, site-, and nest-scales. Results and Conclusions Measures of fecundity varied dramatically across years and spatial scales. At the regional (study-wide) scale, chickadees laid earlier and larger first clutches in warmer springs with minimal storms, and daily nest survival (DSR) increased with a 2-year lag in growing season temperature. Despite a doubling of mountain chickadee density that roughly accompanied the outbreaks of mountain pine beetle and lepidopteran defoliators, we found little evidence at the site scale that fecundity was influenced by insect availability, conspecific density, or predator density. At the nest scale, DSR and brood size increased with clutch size but DSR declined with nest cavity size indicating a positive reproductive effect of small-bodied cavity excavators. Double-brooding, rare in chickadees, occurred frequently in 2005 and 2007, coinciding with early breeding, high food availability from insect outbreaks, and warm spring temperatures with 0-1 spring storms. Our results support the idea that fecundity in secondary cavity-nesting species is impacted directly and indirectly by weather, and indirectly through changes in community dynamics (via cavity resource supply). We stress the importance of adopting holistic, community-level study frameworks to refine our understanding of fecundity in opportunistic and climate-sensitive species in future.
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Affiliation(s)
- Andrea R. Norris
- Science and Technology Branch, Wildlife Research Division, Environment and Climate Change Canada, Delta, BC, Canada,Department of Forest and Conservation Sciences, Faculty of Forestry, University of British Columbia, Vancouver, BC, Canada
| | - Kathy Martin
- Science and Technology Branch, Wildlife Research Division, Environment and Climate Change Canada, Delta, BC, Canada,Department of Forest and Conservation Sciences, Faculty of Forestry, University of British Columbia, Vancouver, BC, Canada
| | - Kristina L. Cockle
- Department of Forest and Conservation Sciences, Faculty of Forestry, University of British Columbia, Vancouver, BC, Canada,CONICET-Universidad Nacional de Misiones, Instituto de Biología Subtropical, Puerto Iguazú, Misiones, Argentina
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5
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González-Ruelas PS, Guadalupe Muñoz-González ZA, Santiago-Pérez AL, Ramírez-López LF, Uribe Mú CA, Rosas-Espinoza VC. Record of Nesting and Fledgling Depredation on Crested Caracara (Caracara cheriway) in its Peri-Urban Habitat in the Guadalajara Metropolitan Area, West-Central Mexico. WEST N AM NATURALIST 2021. [DOI: 10.3398/064.081.0414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Perla Sugey González-Ruelas
- Universidad de Guadalajara, Centro Universitario de Ciencias Biológicas y Agropecuarias, Camino Ing. Ramón Padilla Sánchez No. 2100, Nextipac, Zapopan, Jalisco, C.P. 45200, México
| | - Zayra Arery Guadalupe Muñoz-González
- Universidad de Guadalajara, Centro Universitario de Ciencias Biológicas y Agropecuarias, Camino Ing. Ramón Padilla Sánchez No. 2100, Nextipac, Zapopan, Jalisco, C.P. 45200, México
| | - Ana Luisa Santiago-Pérez
- Universidad de Guadalajara, Centro Universitario de Ciencias Biológicas y Agropecuarias, Camino Ing. Ramón Padilla Sánchez No. 2100, Nextipac, Zapopan, Jalisco, C.P. 45200, México
| | - Luis Fernando Ramírez-López
- Universidad de Guadalajara, Centro Universitario de Ciencias Biológicas y Agropecuarias, Camino Ing. Ramón Padilla Sánchez No. 2100, Nextipac, Zapopan, Jalisco, C.P. 45200, México
| | - Claudia Aurora Uribe Mú
- Universidad de Guadalajara, Centro Universitario de Ciencias Biológicas y Agropecuarias, Camino Ing. Ramón Padilla Sánchez No. 2100, Nextipac, Zapopan, Jalisco, C.P. 45200, México
| | - Verónica Carolina Rosas-Espinoza
- Universidad de Guadalajara, Centro Universitario de Ciencias Biológicas y Agropecuarias, Camino Ing. Ramón Padilla Sánchez No. 2100, Nextipac, Zapopan, Jalisco, C.P. 45200, México
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6
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Smith BL, Snell CL, Reudink MW, Otter KA. Urban-nesting mountain chickadees have a reduced response to a simulated predator. BEHAVIOUR 2021. [DOI: 10.1163/1568539x-bja10122] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Abstract
Anti-predator behaviour is common among birds, but little research exists on whether differences in the predator landscape between urban and rural habitats results in differential anti-predator behaviour. We compared nest-defence behaviour of mountain chickadees (Poecile gambeli) in urban and rural habitats in Kamloops, BC, Canada to a simulated predator model (snake) on top of nest boxes while incubating females were away from nests on foraging bouts. Upon their return, we recorded proximity to the predator model, latency to contact the nest box and enter the nest, and number of gargle and chick-a-dee calls as measures of anti-predator behaviour and compared multivariate “predator aversion scores” across birds occupying either rural or urban landscapes. Rural-nesting birds had more aversive reactions to the predator model than the urban-nesting birds, which may suggest differences in perceived threat of the model, in combination with increased boldness associated with urban-nesting birds.
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Affiliation(s)
- Blaire L. Smith
- University of Northern British Columbia, 3333 University Way, Prince George, BC, Canada V2N 4Z9
| | - Cara L. Snell
- University of Northern British Columbia, 3333 University Way, Prince George, BC, Canada V2N 4Z9
| | | | - Ken A. Otter
- University of Northern British Columbia, 3333 University Way, Prince George, BC, Canada V2N 4Z9
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7
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Stephens CRA, McAmmond BM, Van Hamme JD, Otter KA, Reudink MW, Bottos EM. Analysis of bacterial communities associated with Mountain Chickadees ( Poecile gambeli) across urban and rural habitats. Can J Microbiol 2021; 67:572-583. [PMID: 33656947 DOI: 10.1139/cjm-2020-0320] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Host-associated microbial communities play important roles in wildlife health, but these dynamics can be influenced by environmental factors. Urbanization has numerous effects on wildlife; however, the degree to which wildlife-associated bacterial communities and potential bacterial pathogens vary across urban-rural/native habitat gradients remains largely unknown. We used 16S rRNA gene amplicon sequencing to examine bacterial communities found on Mountain Chickadee (Poecile gambeli) feathers and nests in urban and rural habitats. The feathers and nests in urban and rural sites had similar abundances of major bacterial phyla and dominant genera with pathogenic members. However, richness of bacterial communities and potential pathogens on birds were higher in urban habitats, and potential pathogens accounted for some of the differences in bacterial occurrence between urban and rural environments. We predicted habitat using potential pathogen occurrence with a 90% success rate for feather bacteria, and a 72.2% success rate for nest bacteria, suggesting an influence of urban environments on the presence of potential pathogens. We additionally observed similarities in bacterial communities between nests and their occupants, suggesting bacterial transmission between them. These findings improve our understanding of the bacterial communities associated with urban wildlife and suggest that urbanization impacts the composition of wildlife-associated bacterial communities.
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Affiliation(s)
- Colton R A Stephens
- Department of Biological Sciences, Thompson Rivers University, 805 TRU Way, Kamloops, BC V2C 0C8, Canada
| | - Breanne M McAmmond
- Department of Biological Sciences, Thompson Rivers University, 805 TRU Way, Kamloops, BC V2C 0C8, Canada
| | - Jonathan D Van Hamme
- Department of Biological Sciences, Thompson Rivers University, 805 TRU Way, Kamloops, BC V2C 0C8, Canada
| | - Ken A Otter
- Natural Resources and Environmental Studies, University of Northern British Columbia, 3333 University Way, Prince George, BC V2N 4Z9, Canada
| | - Matthew W Reudink
- Department of Biological Sciences, Thompson Rivers University, 805 TRU Way, Kamloops, BC V2C 0C8, Canada
| | - Eric M Bottos
- Department of Biological Sciences, Thompson Rivers University, 805 TRU Way, Kamloops, BC V2C 0C8, Canada
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8
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Abstract
Urbanization poses a major threat to biodiversity worldwide. We focused on birds as a well-studied taxon of interest, in order to review literature on traits that influence responses to urbanization. We review 226 papers that were published between 1979 and 2020, and aggregate information on five major groups of traits that have been widely studied: ecological traits, life history, physiology, behavior and genetic traits. Some robust findings on trait changes in individual species as well as bird communities emerge. A lack of specific food and shelter resources has led to the urban bird community being dominated by generalist species, while specialist species show decline. Urbanized birds differ in the behavioral traits, showing an increase in song frequency and amplitude, and bolder behavior, as compared to rural populations of the same species. Differential food resources and predatory pressure results in changes in life history traits, including prolonged breeding duration, and increases in clutch and brood size to compensate for lower survival. Other species-specific changes include changes in hormonal state, body state, and genetic differences from rural populations. We identify gaps in research, with a paucity of studies in tropical cities and a need for greater examination of traits that influence persistence and success in native vs. introduced populations.
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9
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An avian urban morphotype: how the city environment shapes great tit morphology at different life stages. Urban Ecosyst 2021. [DOI: 10.1007/s11252-020-01077-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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10
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Urbanization is associated with differences in age class structure in black-capped chickadees (Poecile atricapillus). Urban Ecosyst 2020. [DOI: 10.1007/s11252-020-01039-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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11
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Glądalski M, Mainwaring MC, Bańbura M, Kaliński A, Markowski M, Skwarska J, Wawrzyniak J, Bańbura J, Hartley IR. Consequences of hatching deviations for breeding success: a long-term study on blue tits Cyanistes caeruleus. THE EUROPEAN ZOOLOGICAL JOURNAL 2020. [DOI: 10.1080/24750263.2020.1787532] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Affiliation(s)
- M. Glądalski
- Lancaster Environment Centre, Lancaster University, Lancaster, UK
- Department of Experimental Zoology and Evolutionary Biology, Faculty of Biology and Environmental Protection, University of Łódź, Łódź, Poland
| | - M. C. Mainwaring
- Lancaster Environment Centre, Lancaster University, Lancaster, UK
| | - M. Bańbura
- Museum of Natural History, Faculty of Biology and Environmental Protection, University of Łódź, Łódź, Poland
| | - A. Kaliński
- Department of Experimental Zoology and Evolutionary Biology, Faculty of Biology and Environmental Protection, University of Łódź, Łódź, Poland
| | - M. Markowski
- Department of Experimental Zoology and Evolutionary Biology, Faculty of Biology and Environmental Protection, University of Łódź, Łódź, Poland
| | - J. Skwarska
- Department of Experimental Zoology and Evolutionary Biology, Faculty of Biology and Environmental Protection, University of Łódź, Łódź, Poland
| | - J. Wawrzyniak
- Department of Experimental Zoology and Evolutionary Biology, Faculty of Biology and Environmental Protection, University of Łódź, Łódź, Poland
| | - J. Bańbura
- Department of Experimental Zoology and Evolutionary Biology, Faculty of Biology and Environmental Protection, University of Łódź, Łódź, Poland
| | - I. R. Hartley
- Lancaster Environment Centre, Lancaster University, Lancaster, UK
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12
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Caterpillar phenology predicts differences in timing of mountain chickadee breeding in urban and rural habitats. Urban Ecosyst 2019. [DOI: 10.1007/s11252-019-00884-4] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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13
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Glądalski M, Bańbura M, Kaliński A, Markowski M, Skwarska J, Wawrzyniak J, Zieliński P, Bańbura J. Hatching delays in great tits and blue tits in response to an extreme cold spell: a long-term study. INTERNATIONAL JOURNAL OF BIOMETEOROLOGY 2018; 62:1437-1445. [PMID: 29667035 PMCID: PMC6063324 DOI: 10.1007/s00484-018-1541-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Revised: 04/03/2018] [Accepted: 04/03/2018] [Indexed: 05/15/2023]
Abstract
Variation in ambient temperature affects various life stages of organisms. It has been suggested that climate change not only implies higher global temperatures but also more unpredictable weather and more frequent extreme weather events. Temperature has a major influence on the optimal laying-incubation-hatching dates of insectivorous passerines, because it poses energetic constraints and affects the timing of food abundance. We have been studying breeding characteristics of great tits Parus major and blue tits Cyanistes caeruleus in two areas, an urban parkland and a deciduous forest, around the city of Łódź since 2002. During the egg-laying period in 2017, both tit species at both study areas faced an unusual cold spell as reflected by a sudden decrease in the mean ambient temperature to ca. 2-3 °C for about 5 days, which caused mean hatching delays of up to 6 days. Since flexibility of behavior plays a major role in adjusting to unpredictable weather conditions, examining its limits may be an important goal for future research.
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Affiliation(s)
- Michał Glądalski
- Department of Experimental Zoology and Evolutionary Biology, Faculty of Biology and Environmental Protection, University of Łódź, Banacha 12/16, 90-237, Łódź, Poland.
| | - Mirosława Bańbura
- Museum of Natural History, Faculty of Biology and Environmental Protection, University of Łódź, Kilińskiego 101, 90-011, Łódź, Poland
| | - Adam Kaliński
- Department of Experimental Zoology and Evolutionary Biology, Faculty of Biology and Environmental Protection, University of Łódź, Banacha 12/16, 90-237, Łódź, Poland
| | - Marcin Markowski
- Department of Experimental Zoology and Evolutionary Biology, Faculty of Biology and Environmental Protection, University of Łódź, Banacha 12/16, 90-237, Łódź, Poland
| | - Joanna Skwarska
- Department of Experimental Zoology and Evolutionary Biology, Faculty of Biology and Environmental Protection, University of Łódź, Banacha 12/16, 90-237, Łódź, Poland
| | - Jarosław Wawrzyniak
- Department of Experimental Zoology and Evolutionary Biology, Faculty of Biology and Environmental Protection, University of Łódź, Banacha 12/16, 90-237, Łódź, Poland
| | - Piotr Zieliński
- Department of Ecology and Vertebrate Zoology, Faculty of Biology and Environmental Protection, University of Łódź, Banacha 12/16, 90-237, Łódź, Poland
| | - Jerzy Bańbura
- Department of Experimental Zoology and Evolutionary Biology, Faculty of Biology and Environmental Protection, University of Łódź, Banacha 12/16, 90-237, Łódź, Poland
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14
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Bonderud ES, Otter KA, Burg TM, Marini KLD, Reudink MW. Patterns of extra-pair paternity in mountain chickadees. Ethology 2018. [DOI: 10.1111/eth.12747] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Erica S. Bonderud
- Natural Resources and Environmental Studies; University of Northern British Columbia; Prince George BC Canada
| | - Ken A. Otter
- Natural Resources and Environmental Studies; University of Northern British Columbia; Prince George BC Canada
| | - Theresa M. Burg
- Department of Biological Sciences; University of Lethbridge; Lethbridge AB Canada
| | - Kristen L. D. Marini
- Department of Biological Sciences; Thompson Rivers University; Kamloops BC Canada
| | - Matthew W. Reudink
- Department of Biological Sciences; Thompson Rivers University; Kamloops BC Canada
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15
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Bonderud ES, Otter KA, Murray BW, Marini K, Burg TM, Reudink MW. Effects of parental condition and nesting habitat on sex allocation in the mountain chickadee. BEHAVIOUR 2017. [DOI: 10.1163/1568539x-00003460] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
When the reproductive value of sons vs. daughters differs, sex allocation theory predicts females should bias the sex ratio of their broods towards the higher-value sex. Females in numerous bird species appear to bias offspring sex in response to self and mate condition, and breeding habitat quality. Over three breeding seasons, we monitored mountain chickadees breeding along a rural to urban habitat gradient. We did not find female condition or the condition of the putative father or true genetic father to influence offspring sex. We found marginal evidence for sex allocation in relation to habitat urbanization, though opposite to our predictions. In urban habitat, offspring were more likely to be female as the degree of habitat urbanization increased. We suggest habitat quality may be influential in mountain chickadee reproductive decisions; however, the ecology of mountain chickadees may not fulfill the assumptions of sex allocation theory.
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Affiliation(s)
- Erica S. Bonderud
- Natural Resources and Environmental Studies, University of Northern British Columbia, Prince George, BC, Canada
| | - Ken A. Otter
- Natural Resources and Environmental Studies, University of Northern British Columbia, Prince George, BC, Canada
| | - Brent W. Murray
- Natural Resources and Environmental Studies, University of Northern British Columbia, Prince George, BC, Canada
| | - Kristen L.D. Marini
- Department of Biological Sciences, Thompson Rivers University, Kamloops, BC, Canada
| | - Theresa M. Burg
- Department of Biological Sciences, University of Lethbridge, Lethbridge, AB, Canada
| | - Matthew W. Reudink
- Department of Biological Sciences, Thompson Rivers University, Kamloops, BC, Canada
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16
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Marini KL, Reudink MW, LaZerte SE, Otter KA. Urban mountain chickadees (Poecile gambeli) begin vocalizing earlier, and have greater dawn chorus output than rural males. BEHAVIOUR 2017. [DOI: 10.1163/1568539x-00003464] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Vocal output during the dawn chorus is often an honest indicator of male quality, where males with greater access to food and in better condition produce more vocalizations. We compare the vocal output among male mountain chickadees living along an urbanization gradient to assess how urbanization affects male signalling. Chickadees forage in the canopy, and because urban habitats are associated with lower canopy volume, we predicted that urban habitats may offer lower food and thus lead to reduced song output. Contrary to our predictions, males in more urbanized habitats had greater vocal output. We suggest that despite decreased canopy cover, urban birds may have greater access to food in both the breeding and pre-breeding seasons due to differences in both supplementary resources and vegetation composition of urban vs rural landscapes in our area. Living in urban habitats may allow males to enter the breeding season in better condition.
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Affiliation(s)
- Kristen L.D. Marini
- Department of Biological Sciences, Thompson Rivers University, 805 TRU Way, Kamloops, BC, Canada V2C 0C8
| | - Matthew W. Reudink
- Department of Biological Sciences, Thompson Rivers University, 805 TRU Way, Kamloops, BC, Canada V2C 0C8
| | - Stefanie E. LaZerte
- Department of Geography, Thompson Rivers University, 805 TRU Way, Kamloops, BC, Canada V2C 0C8
- Natural Resources and Environmental Studies, University of Northern British Columbia, 3333 University Way, Prince George, BC, Canada V2N 4Z9
| | - Ken A. Otter
- Natural Resources and Environmental Studies, University of Northern British Columbia, 3333 University Way, Prince George, BC, Canada V2N 4Z9
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