Dear territory or dear partner? Causes and consequences of breeding dispersal in a highly territorial bird of prey with a strong pair bond

Behavioral Ecology and Sociobiology, Journal Year: 2023, Volume and Issue: 77(10)

Published: Sept. 23, 2023

Abstract Territorial species are unlikely to show extensive movements between breeding seasons. This is especially true for long-lived species, which often have strong pair bonding and can occupy the same territory years. However, also in such individuals may face situations that lead a shift. Here, we use comprehensive dataset documenting 40 years of behavior tawny owl ( Strix aluco ) – with high site tenacity mate fidelity examine factors affecting decisions whether or not move another how far, as well fitness consequences thereof. We found likelihood distance movement either sexes strongly associated change partner, indicating loss cause dispersal. Moreover, change, new territory, had negative effects on subsequent reproductive performance: changed partner were more likely skip reproduction year and, those cases they bred, produced smaller clutches raised fewer offspring. Our findings indicate owls almost exclusively when searching has profound their performance. Overall, our study provides evidence territoriality monogamy linked fitness, but be important than fidelity, because involved specific tasks cooperation ensures success consequently, increases fitness. Significance statement Breeding dispersal, sites, entail costs animal territorial display fidelity. studied dispersal performances ), highly species. moved frequently died. Either showed an equal probability move, effect was stronger females males after change. delayed reproduction, clutch higher reproduction. share holding territory.

Language: Английский

Dispersal patterns of the endangered Crested Ibis suggest high breeding densities drive natal dispersal

Ornithological Applications, Journal Year: 2022, Volume and Issue: 125(1)

Published: Oct. 28, 2022

Abstract Although dispersal is a key driver of population dynamics and species distributions, we still know little about how it affects the endangered restricted-range species. Density-dependent effects on in particular may be critical for range expansion recovering populations. After 1981, when last 7 wild individuals Crested Ibis (Nipponia nippon) were discovered China, remained confined to single location (“original nesting area”) until 2000 (<24 breeding pairs). Then, began significant spatial numerical toward new sites (“secondary areas”). Our analyses long-term (1993–2017) individual resighting data (n = 193) found that natal was common (~77.2%), whereas rare (~2.1%). Breeding density negatively related productivity, more likely low-density areas. The Weibull distribution provided best fit observed distances, indicating presence long-distance dispersers. cannot rule out effect mechanisms inherent regardless density, our findings suggest probability density-dependent, implying role intraspecific competition spreading region. We expect spread throughout region if conservation programs can identify protect potential reintroduction areas at large scale allow dispersing settle into

Language: Английский

Incubation behaviour of a boreal, food-caching passerine nesting in sub-zero temperatures

Published: Jan. 13, 2024

Our understanding of avian incubation behaviour is primarily derived from species that nest in the temperate conditions spring and summer. This leaves uncertainties about strategies employed by a relatively small number adapted to breed under sub-zero, winter-like conditions. We used in-nest temperature loggers (iButtons) monitor behaviours Canada Jays, cache-reliant, year-round residents boreal sub-alpine environments late winter/early have female-only incubation. Females had high levels daytime attentiveness (92 ± 3% spent on nest; SD), taking an average only 5.5 (± 0.1) off-bouts per day with mean duration 13.3 0.2) min. bout. Variation was driven off-bout duration, suggesting may be limited reduce activity around avoid attracting predators. In contrast expectations, weather (mean daily total rainfall) were not associated variation either or off-bouts. results suggest Jays are likely shaped prevailing but instead predation threat availability cached food, latter which reduces foraging opportunity costs allowing females reliably acquire sufficient food during few times they leave each day.

Language: Английский