Senescence in the wild: Insights from a long-term study on Seychelles warblers

Hammers, Martijn; Kingma, Sjouke A.; Bebbington, Kat; Crommenacker, Janske van de; Spurgin, Lewis G.; Richardson, David S.; Burke, Terry; Dugdale, Hannah L.; Komdeur, Jan

doi:10.1016/j.exger.2015.08.019

Cited by 56 publications

(91 citation statements)

References 127 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…According to our analysis, both male and female loons enjoy a high rate of survival until about their mid 20s, at which point the mortality rate increases by roughly a factor of four. While sparse data in older age‐classes prevented us from ascertaining the precise shape of the decline in survival, its extent appears comparable to that reported in other free‐living birds (Bouwhuis et al , Pardo et al , Hammers et al ).…”

Section: Discussionsupporting

confidence: 78%

The long shadow of senescence: age impacts survival and territory defense in loons

Piper

Brunk

Flory³

et al. 2017

Journal of Avian Biology

View full text Add to dashboard Cite

Senescence, increased mortality that occurs among animals of advanced age, impacts behavior and ecology in many avian species. We investigated actuarial, reproductive, and behavioral senescence using capture, marking, and resighting data from a 26‐year study of common loons Gavia immer. Territorial residents of both sexes exhibited high annual survival (0.94) until their mid 20s, at which point survival fell to 0.76 and 0.77 in males and females, respectively. Sexual symmetry in actuarial senescence is somewhat surprising in this species, because males make a substantially greater investment in territory defense and chick‐rearing and because males engage in lethal contests for territory ownership. Survival of displaced breeders (0.80) was lower than that of territorial residents in both young and old individuals. Old males and females also experienced slightly higher annual probability of eviction (0.16 for males; 0.17 for females) than prime‐aged breeders (0.13 for both sexes), indicating senescence in territory defense. Prime‐aged males reclaimed territories at a high rate (0.49), in contrast to females of the same age (0.33). However, old males resettled with success (0.35) similar to old females (0.31), suggesting that males decline in competitive ability as they age. Nonetheless males, but not females, showed an apparent increase in breeding success over the entire lifetime, a possible indication that very old males make a terminal investment in reproductive output at the cost of survival.

show abstract

Section: Discussionsupporting

confidence: 78%

The long shadow of senescence: age impacts survival and territory defense in loons

Piper

Brunk

Flory³

et al. 2017

Journal of Avian Biology

View full text Add to dashboard Cite

show abstract

“…Territories are stable year‐round (breeders usually remain present until death; Hammers et al. ) and are defended against intruding conspecifics (who are physically attacked; Kingma et al. ).…”

Section: Methodsmentioning

confidence: 99%

“…Breeding vacancies, which arise following breeder mortality, are limited as Seychelles warblers live up to 18 years (average life span from fledging = 5.5 year; Komdeur ; Hammers et al. ) and all suitable habitat on the island is occupied (Komdeur ; Komdeur et al. ).…”

Section: Methodsmentioning

confidence: 99%

Delayed dispersal and the costs and benefits of different routes to independent breeding in a cooperatively breeding bird

et al. 2016

Self Cite

View full text Add to dashboard Cite

Why sexually mature individuals stay in groups as nonreproductive subordinates is central to the evolution of sociality and cooperative breeding. To understand such delayed dispersal, its costs and benefits need to be compared with those of permanently leaving to float through the population. However, comprehensive comparisons, especially regarding differences in future breeding opportunities, are rare. Moreover, extraterritorial prospecting by philopatric individuals has generally been ignored, even though the factors underlying this route to independent breeding may differ from those of strict philopatry or floating. We use a comprehensive predictive framework to explore how various costs, benefits and intrinsic, environmental and social factors explain philopatry, prospecting, and floating in Seychelles warblers (Acrocephalus sechellensis). Not only floaters more likely obtained an independent breeding position before the next season than strictly philopatric individuals, but also suffered higher mortality. Prospecting yielded similar benefits to floating but lower mortality costs, suggesting that it is overall more beneficial than floating and strict philopatry. While prospecting is probably individual‐driven, although limited by resource availability, floating likely results from eviction by unrelated breeders. Such differences in proximate and ultimate factors underlying each route to independent breeding highlight the need for simultaneous consideration when studying the evolution of delayed dispersal.

show abstract

“…Reproductive performance may increase (Andrade and Kasumovic, 2005;Isaac and Johnson, 2005;Creighton et al, 2009;Weladji et al, 2010) or it may decline (Fig. 1C) (Finn, 1963;Newton et al, 1981;Descamps et al, 2009;Hammers et al, 2015;Warner et al, 2016) during a female's final reproductive event(s).…”

Section: Proposed Physiological Basis For Life-history Patternsmentioning

confidence: 99%

Current versus future reproduction and longevity: a re-evaluation of predictions and mechanisms

Zhang

Hood

2016

Journal of Experimental Biology

View full text Add to dashboard Cite

Oxidative damage is predicted to be a mediator of trade-offs between current reproduction and future reproduction or survival, but most studies fail to support such predictions. We suggest that two factors underlie the equivocal nature of these findings: (1) investigators typically assume a negative linear relationship between current reproduction and future reproduction or survival, even though this is not consistently shown by empirical studies; and (2) studies often fail to target mechanisms that could link interactions between sequential lifehistory events. Here, we review common patterns of reproduction, focusing on the relationships between reproductive performance, survival and parity in females. Observations in a range of species show that performance between sequential reproductive events can decline, remain consistent or increase. We describe likely bioenergetic consequences of reproduction that could underlie these changes in fitness, including mechanisms that could be responsible for negative effects being ephemeral, persistent or delayed. Finally, we make recommendations for designing future studies. We encourage investigators to carefully consider additional or alternative measures of bioenergetic function in studies of life-history trade-offs. Such measures include reactive oxygen species production, oxidative repair, mitochondrial biogenesis, cell proliferation, mitochondrial DNA mutation and replication error and, importantly, a measure of the respiratory function to determine whether measured differences in bioenergetic state are associated with a change in the energetic capacity of tissues that could feasibly affect future reproduction or lifespan. More careful consideration of the life-history context and bioenergetic variables will improve our understanding of the mechanisms that underlie the life-history patterns of animals.

show abstract

Senescence in the wild: Insights from a long-term study on Seychelles warblers

Cited by 56 publications

References 127 publications

The long shadow of senescence: age impacts survival and territory defense in loons

The long shadow of senescence: age impacts survival and territory defense in loons

Delayed dispersal and the costs and benefits of different routes to independent breeding in a cooperatively breeding bird

Current versus future reproduction and longevity: a re-evaluation of predictions and mechanisms

Contact Info

Product

Resources

About