Avian Reproduction in a Warming World

Frontiers in Ecology and Evolution, Journal Year: 2020, Volume and Issue: 8

Published: Oct. 8, 2020

Weather influences both the distribution and life-history strategies of birds. Temperature ranks amongst more important weather parameters in this regard since warming springs temperate high latitudes frequent heat-waves globally have caused major changes breeding phenology negatively affected adult juvenile survival, respectively. Both long-term stochastic temperature can fundamental consequences for avian reproduction even when effects are not lethal, such as via thermal constraints on parental provisioning chick growth. To date, most what we know about nestling development effort during is based correlative data. In addition, an increasing amount evidence indicates that change also significantly affects birds breed cooler areas, which so far has been somewhat overlooked. Therefore, perspective piece, outline existing literature behaviour, with emphasis needs to be done address causal under climate change. We finish by providing outlook over future avenues research, give suggestions some specific areas might especially promising developing field research.

Language: Английский

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Heat dissipation capacity influences reproductive performance in an aerial insectivore

Journal of Experimental Biology, Journal Year: 2020, Volume and Issue: unknown

Published: Jan. 1, 2020

Climatic warming is predicted to increase the frequency of extreme weather events, which may reduce an individual's capacity for sustained activity because thermal limits. We tested whether risk overheating limit parental provisioning aerial insectivorous bird in population decline. For many seasonally breeding birds, parents are thought operate close energetic ceiling during 2-3 week chick-rearing period. The factors determining remain unknown, although it be set by dissipate body heat (the dissipation limitation hypothesis). Over two seasons we experimentally trimmed ventral feathers female tree swallows (Tachycineta bicolor) provide a window. then monitored maternal and paternal rates, nestling growth rates fledging success. found effect our experimental treatment was context dependent. Females with enhanced fed their nestlings at higher than controls when conditions were hot, but reverse true under cool conditions. Control females mates both reduced foraging hot In contrast, male partners maintained constant feeding rate across temperatures, suggesting attempts match partners. On average, heavier controls, did not have probability fledging. suggest that removal constraint allowed additionally provided advantage via increased transfer brooding. Our data support hypothesis depending on temperature, can influence reproductive success insectivores.

Language: Английский

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Experimental evidence that hyperthermia limits offspring provisioning in a temperate-breeding bird

Royal Society Open Science, Journal Year: 2020, Volume and Issue: 7(10), P. 201589 - 201589

Published: Oct. 1, 2020

In many vertebrates, parental care can require long bouts of daily exercise that span several weeks. Exercise, especially in the heat, raises body temperature, and lead to hyperthermia. Typical strategies for regulating temperature during endurance include modifying performance avoid hyperthermia (anticipatory regulation) allowing rise above normothermic levels brief periods time (facultative hyperthermia). Facultative is commonly employed by desert birds economize on water, but this strategy may also be important chick-rearing reducing offspring provisioning when thermoregulatory demands are high. study, we tested how balance their own against need provision dependent offspring. We experimentally increased heat dissipation capacity breeding female tree swallows ( Tachycineta bicolor ) trimming ventral feathers remotely monitored rates, probability Birds with an dissipate (i.e. trimmed treatment) maintained higher feeding rates than controls at high ambient temperatures (greater or equal 25°C), while maintaining lower temperatures. However, highest individuals became hyperthermic. These results provide evidence use both anticipatory regulation facultative performance. With rising global temperatures, increase frequency maintain nestling provisioning, thereby maximize reproductive success.

Language: Английский

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Measuring body temperature in birds – the effects of sensor type and placement on estimated temperature and metabolic rate

Journal of Experimental Biology, Journal Year: 2023, Volume and Issue: 226(24)

Published: Nov. 16, 2023

Several methods are routinely used to measure avian body temperature, but different vary in invasiveness. This may cause stress-induced increases temperature and/or metabolic rate and, hence, overestimation of both parameters. Choosing an adequate measurement method is therefore key accurately characterizing animal's thermal and phenotype. Using great tits (Parus major) four common with levels invasiveness (intraperitoneal, cloacal, subcutaneous, cutaneous), we evaluated the preciseness measurements effects on resting (RMR) over a 40°C range ambient temperatures. None caused or underestimation RMR compared un-instrumented birds, skin estimates did not differ between thermoneutrality. However, was lower all other below These results provide empirical guidance for future research that aims small bird models.

Language: Английский

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Experimental facilitation of heat loss affects work rate and innate immune function in a breeding passerine bird

Journal of Experimental Biology, Journal Year: 2020, Volume and Issue: unknown

Published: Jan. 1, 2020

The capacity to get rid of excess heat produced during hard work is a possible constraint on parental effort reproduction (heat dissipation limit [HDL] theory). We released hard-working blue tits (Cyanistes caeruleus) from this by experimentally removing ventral plumage. then assessed if changed their reproductive (feeding rate and nestling size) levels self-maintenance (change in body mass innate immune function). Feather-clipped females reduced the number feeding visits increased constitutive immunity compared unclipped but did not fledge smaller nestlings. Thus, they without compromising current output. In contrast, feather-clipping affect or function males, despite loss rate. Our results show that analyses physiological parameters, such as function, can be important when trying understand sources variation investment versus risk overheating influence reproduction.

Language: Английский

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Limits to sustained energy intake XXXII: Hot again: dorsal shaving increases energy intake and milk output in golden hamsters (Mesocricetus auratus)

Journal of Experimental Biology, Journal Year: 2020, Volume and Issue: unknown

Published: Jan. 1, 2020

Golden hamsters have four times the body size of mice, raise very large litters and are required to produce quantities milk during 18-day lactation period. We previously proposed that they may be prone being limited by their heat dissipation capacity. Studies where lactating females shaved elevate capacity yielded conflicting data so far. With short pregnancy ∼18 days, reported high skin temperatures, serve as an ideal model elucidate role epilation for energy budgets in mammals. one group dorsally on sixth day lactation, tested if elevated would enable them higher intakes better food-to-milk conversion rates. Indeed, we observed from had 6% mass 0.78°C lower temperature than control lactation. When focusing phase peak significantly (10%) gross intake food 23.4% more output females, resulting 3.3 g individual pup weights. conclude shaving off females' fur, even though restricted dorsal surface, consequences female metabolism improved production growth line with our previous work limitation. Our new golden confirm a limiting factor sustained metabolic rate some small mammals emphasise effects relatively manipulation such fur removal females.

Language: Английский

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Body temperature is a repeatable trait in a free-ranging passerine bird

Journal of Experimental Biology, Journal Year: 2021, Volume and Issue: 224(20)

Published: Sept. 9, 2021

ABSTRACT Body temperature (Tb) affects animal function through its influence on rates of biochemical and biophysical reactions, the molecular structures proteins tissues, and, ultimately, organismal performance. Despite importance in driving physiological processes, there are few data how much variation Tb exists within populations organisms, whether this consistently differs among individuals over time (i.e. repeatability a trait). Here, using thermal radio-frequency identification implants, we quantified Tb, both context fixed average environment (∼21°C) across ambient temperatures (6–31°C), free-living population tree swallows (Tachycineta bicolor, n=16). By experimentally trimming ventral plumage subset female (n=8), also asked is influenced by capacity to dissipate body heat. We found that male swallow was repeatable at 21°C (R=0.89–92), but less than (Rfemale=0.10, Rmale=0.58), which may be due differences parental investment. Trimmed birds had lower control (by ∼0.5°C), did not differ as heat dissipation capacity. This suggests trimmed adjusted their account for effects loss Tb. Our study provides first critical step toward understanding responsive natural selection, predicting will respond climatic warming.

Language: Английский

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Variation in reproductive investment increases body temperature amplitude in a temperate passerine

Oecologia, Journal Year: 2021, Volume and Issue: 197(2), P. 365 - 371

Published: Sept. 7, 2021

Many birds and mammals show substantial circadian variation in body temperature, which has been attributed to fluctuations ambient temperature energy reserves. However, fully understand the over course of day, we also need consider effects work rate. We made use a dataset on during resting active periods female marsh tits (Poecile palustris) that bred temperate area were subjected experimental changes reproductive investment through brood size manipulations. Furthermore, amplitude increased with daytime, but unaffected by nighttime, temperature. Amplitudes females manipulated broods 44% above predictions based inter-specific allometric relationships. In extreme cases, amplitudes > 100% predicted values. no individual realised maximum potential (8.5 °C, i.e. difference between highest lowest within population) seemed prioritise either reduction at night or an increase day. This suggests might be constrained costs preclude extensive both low nighttime high daytime temperatures same individual. range found here (0.5-6.7 °C) have previously mostly reported from sub-tropical and/or arid habitats. comparable values can amongst relatively cool, regions, partly due pronounced

Language: Английский

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Mid‐summer arrival by Blue Grosbeaks at the northern extent of their breeding range: evidence for dual breeding?

Journal of Field Ornithology, Journal Year: 2021, Volume and Issue: 92(2), P. 127 - 142

Published: June 1, 2021

Anecdotal observations of mid-summer arrival Blue Grosbeaks (Passerina caerulea) in South Dakota, the northern portion their breeding range, suggest that this species may show a pattern at grounds differs from other migrant birds. We assessed possibility using three different approaches: (1) data mining citizen-science database for Dakota bird observations, (2) roadside surveys 2019 and 2020, (3) analyses temporal occurrence patterns eBird southern portions range. Observations eastern central, but not western, peaked late June through early August, later than birds occupying similar habitats. Results revealed 57 (2020) to 76% (2019) population central arrived after mid-June. Finally, Grosbeak decreased May mid-June August range (Texas Oklahoma), increased Dakota. Mid-summer phenology are consistent with hypothesis dual North America, first brood second part However, possible explanations these differences patterns, such as wandering failed acquire territories have yet been conclusively ruled out. If strategy is confirmed, would represent documentation south-then-north New World. Llegada mediados del verano de Passerina caerulea la extensión norte su área reproducción: ¿evidencia reproducción dual? Observaciones anecdóticas llegada picogrueso azul Sur, en parte reproducción, sugieren que esta especie puede mostrar un patrón los criaderos difiere otras especies aves migratorias. Evaluamos posibilidad utilizando tres enfoques diferentes: extracción datos una base ciencia ciudadana para las observaciones encuestas al borde carretera Sur y análisis ocurrencia entre patrones porciones sur reproducción. Las P. oriental pero no occidental, alcanzaron punto máximo desde finales junio hasta principios agosto, más tardía migratorias ocupan hábitats similares. Los resultados carreteras revelaron 57% población reproductora el este centro llegó después junio. Finalmente, disminuyó mayo agosto aumentó distribución Sur. La fenología diferentes son consistentes con hipótesis porción América Norte, primera cría segundo Sin embargo, aún se han descartado manera concluyente posibles explicaciones estas diferencias temporales ocurrencia, como errantes lograron adquirir territorios distribución. Si confirma estrategia dual, esto representaría documentación sur-luego-norte Nuevo Mundo. Fig. S1. Weekly kernel density estimates by ordinal date all checklists spatially explicit each state throughout April season. Red, yellow green high, intermediate low density, respectively. S2. Cumulative frequency accumulation curves season function six benchmark species. Data Grosbeak, Field Sparrow, Dickcissel, Indigo Bunting, Orchard Oriole presented Texas Oklahoma, Rose-breasted Bobolink cumulative (for comparison Grosbeak) only because do nest S3. meeting quality control criteria states (Texas, Kansas, Nebraska, Dakota) corrected uneven sampling effort among scaling weekly number submitted For we randomly selected sub-set among-state analyses. yellow, intermediate, Please note: The publisher responsible content or functionality any supporting information supplied authors. Any queries (other missing content) should be directed corresponding author article.

Language: Английский

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