Exceptionally high apparent adult survival in three tropical species of plovers in Madagascar

Steroid hormones have similar functions across vertebrates, but circulating concentrations can vary dramatically among species. We examined the hypothesis that variation in titres of corticosterone (Cort) and testosterone (T) is related to life-history traits of avian species. We predicted that Cort would reach higher levels under stress in species with higher annual adult survival rates since Cort is thought to promote physiological and behavioural responses that reduce risk to the individual. Conversely, we predicted that peak T during the breeding season would be higher in short-lived species with high mating effort as this hormone is known to promote male fecundity traits. We quantified circulating hormone concentrations and key life-history traits (annual adult survival rate, breeding season length, body mass) in males of free-living bird species during the breeding season at a temperate site (northern USA) and a tropical site (central Panama). We analysed our original data by themselves, and also combined with published data on passerine birds to enhance sample size. In both approaches, variation in baseline Cort (Cort0) among species was inversely related to breeding season length and body mass. Stress-induced corticosterone (MaxCort) also varied inversely with body mass and, as predicted, also varied positively with annual adult survival rates. Furthermore, species from drier and colder environments exhibited lower MaxCort than mesic and tropical species; T was lowest in species from tropical environments. These findings suggest that Cort0, MaxCort and T modulate key vertebrate life-history responses to the environment, with Cort0 supporting energetically demanding processes, MaxCort promoting survival and T being related to mating success.

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Climate predicts which sex acts as helpers among cooperatively breeding bird species

Biology Letters ◽

10.1098/rsbl.2016.0863 ◽

2017 ◽

Vol 13 (1) ◽

pp. 20160863 ◽

Cited By ~ 7

Author(s):

Guoyue Zhang ◽

Qingtian Zhao ◽

Anders Pape Møller ◽

Jan Komdeur ◽

Xin Lu

Keyword(s):

Bird Species ◽

Adult Survival ◽

Sex Bias ◽

Tropical Species ◽

Ecological Constraints ◽

Breeding Bird ◽

Adult Females ◽

Cooperatively Breeding ◽

Demographic Response ◽

Potential Determinant

Among avian cooperative breeders, help in raising offspring is usually provided by males or by both sexes. Sex bias in helping should evolve in response to sex-specific ecological constraints on independent reproduction, with mate shortage for males and breeding vacancy shortage for each sex. Given that male-biased adult sex ratios are prevalent among birds, we predict that male-only helping mainly occurs in temperate species where fast population turnovers deriving from low adult annual survival allow all adult females to hold breeding vacancies, whereas some males overflow as helpers, and both-sex helping in tropical species where saturated habitats prevent not only males, but also females from breeding themselves. As expected, we found that across species, adult survival increased towards tropical zones and warmer climates, and higher adult survival tended to be associated with both-sex helping. Furthermore, sex bias in helping was predicted by latitude and ambient temperature. Our findings of demographic response of species to climate as a potential determinant of bias in helper sex uncover how ecological constraints operate to limit independent reproduction in sex-specific ways.

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Survival of a long-lived single island endemic, the Raso lark Alauda razae, in relation to age, fluctuating population and rainfall

Scientific Reports ◽

10.1038/s41598-019-55782-8 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 3

Author(s):

E. G. Dierickx ◽

R. A. Robinson ◽

M. de L. Brooke

Keyword(s):

Strong Evidence ◽

Survival Rates ◽

Adult Survival ◽

Tropical Species ◽

High Survival ◽

Cape Verdean ◽

Island Endemic ◽

The Face ◽

Dry Conditions ◽

Population Sizes

AbstractEstimating and understanding variation in survival rates is crucial for the management of threatened species, especially those with limited population sizes and/or restricted ranges. Using a capture-resighting dataset covering 2004–2017, we estimate adult survival in the Raso lark Alauda razae, a Critically Endangered single-island Cape Verdean endemic, whose population varied 25-fold during the study. Average annual adult survival was similar for males (0.813 ± 0.011) and females (0.826 ± 0.011) over the period. These values are high for a temperate passerine but not unusual for an insular tropical species like the lark. The oldest bird was recorded 13 years after first ringing. There was strong evidence that survival varied among years (between 0.57 and 0.95), being generally higher in wetter years. Survival, especially of males, was lower when the population was large, but only in drier years. Survival declined with age but there was no evidence that this decline was other than linear. High survival, even in the face of dry conditions, at least when the population is depressed, has probably contributed to the persistence of the species on its 7 km2 island home over several centuries.

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Population Dynamics and Biological Feasibility of Sustainable Harvesting as a Conservation Strategy for Tropical and Temperate Freshwater Turtles

10.1101/786806 ◽

2019 ◽

Author(s):

Angga Rachmansah ◽

Darren Norris ◽

James P. Gibbs

Keyword(s):

Life History ◽

Population Growth ◽

Sexual Maturity ◽

Life History Traits ◽

Conservation Strategy ◽

Adult Survival ◽

Freshwater Turtle ◽

Tropical Species ◽

Sustainable Harvest ◽

Turtle Species

AbstractBackgroundConservation strategies are urgently needed for tropical turtles. Studies conducted exclusively in the temperate zone have revealed that the suite of life history traits that characterizes turtles and includes delayed sexual maturity and high adult survivorship makes sustainable harvest programs an unviable strategy for turtle conservation. However, most turtles are tropical in distribution and the tropics have higher, more constant and more extended ambient temperature regimes that, in general, are more favorable for population growth.MethodsTo estimate the capacity of freshwater turtle species from temperate and tropical regions to sustain harvest we synthesized life history traits from 165 freshwater turtle species in 12 families (Carettochelydae, Chelidae, Chelydridae, Dermatemydidae, Emydidae, Geoemydidae, Kinosternidae, Pelomedusidae, Platysternidae, Podocnemididae, Staurotypidae and Trionychidae). The influence of climate variables and latitude on freshwater turtle life history traits (clutch size, clutch frequency, age at sexual maturity, and annual adult survival) were examined using Generalized Additive Models. The biological feasibility of sustainable harvest in temperate and tropical species was evaluated using a sensitivity analysis of population growth rates obtained from stage structured matrix population models.ResultsTurtles at low latitudes (tropical zones) exhibit smaller clutch sizes, higher clutch frequency, and earlier age at sexual maturity than those at high latitudes (temperate zone). Adult survival increased weakly with latitude and declined significantly with increasing bioclimatic temperature (mean temperature of warmest quarter). A modeling synthesis of these data indicates that the interplay of life history traits does not create higher harvest opportunity in adults of tropical species. Yet we found potential for sustainable exploitation of eggs in tropical species.ConclusionsSustainable harvest as a conservation strategy for tropical turtles appears to be as biologically problematic as in temperature zones and likely only possible if the focus is on limited harvest of eggs. Further studies are urgently needed to understand how the predicted population surplus in early life stages can be most effectively incorporated into conservation programs for tropical turtles increasingly threatened by unsustainable exploitation, climate change and deforestation.

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Experimentally increased costs of parental care are shunted to offspring in species with extended care

10.32942/osf.io/y8wx4 ◽

2019 ◽

Author(s):

Gretchen F. Wagner ◽

Emeline Mourocq ◽

Michael Griesser

Keyword(s):

Life History ◽

Parental Care ◽

Total Duration ◽

Bird Species ◽

Life History Strategy ◽

Experimental Treatment ◽

Cost Of Care ◽

Adult Survival ◽

Supporting Evidence ◽

Trade Offs

Biparental care systems are a valuable model to examine conflict, cooperation, and coordination between unrelated individuals, as the product of the interactions between the parents influences the fitness of both individuals. A common experimental technique for testing coordinated responses to changes in the costs of parental care is to temporarily handicap one parent, inducing a higher cost of providing care. However, dissimilarity in experimental designs of these studies has hindered interspecific comparisons of the patterns of cost distribution between parents and offspring. Here we apply a comparative experimental approach by handicapping a parent at nests of five bird species using the same experimental treatment. In some species, a decrease in care by a handicapped parent was compensated by its partner, while in others the increased costs of care were shunted to the offspring. Parental responses to an increased cost of care primarily depended on the total duration of care that offspring require. However, life history pace (i.e., adult survival and fecundity) did not influence parental decisions when faced with a higher cost of caring. Our study highlights that a greater attention to intergenerational trade-offs is warranted, particularly in species with a large burden of parental care. Moreover, we demonstrate that parental care decisions may be weighed more against physiological workload constraints than against future prospects of reproduction, supporting evidence that avian species may devote comparable amounts of energy into survival, regardless of life history strategy.

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Persistence of giants: population dynamics of the limpet Scutellastra laticostata on rocky shores in Western Australia

Marine Ecology Progress Series ◽

10.3354/meps13364 ◽

2020 ◽

Vol 646 ◽

pp. 79-92

Author(s):

RE Scheibling ◽

R Black

Keyword(s):

Population Dynamics ◽

Western Australia ◽

Size Structure ◽

Survival Rates ◽

Maximum Size ◽

High Rate ◽

Adult Survival ◽

Rocky Shores ◽

Adult Size ◽

Decadal Time Scale

Population dynamics and life history traits of the ‘giant’ limpet Scutellastra laticostata on intertidal limestone platforms at Rottnest Island, Western Australia, were recorded by interannual (January/February) monitoring of limpet density and size structure, and relocation of marked individuals, at 3 locations over periods of 13-16 yr between 1993 and 2020. Limpet densities ranged from 4 to 9 ind. m-2 on wave-swept seaward margins of platforms at 2 locations and on a rocky notch at the landward margin of the platform at a third. Juvenile recruits (25-55 mm shell length) were present each year, usually at low densities (<1 m-2), but localized pulses of recruitment occurred in some years. Annual survival rates of marked limpets varied among sites and cohorts, ranging from 0.42 yr-1 at the notch to 0.79 and 0.87 yr-1 on the platforms. A mass mortality of limpets on the platforms occurred in 2003, likely mediated by thermal stress during daytime low tides, coincident with high air temperatures and calm seas. Juveniles grew rapidly to adult size within 2 yr. Asymptotic size (L∞, von Bertalanffy growth model) ranged from 89 to 97 mm, and maximum size from 100 to 113 mm, on platforms. Growth rate and maximum size were lower on the notch. Our empirical observations and simulation models suggest that these populations are relatively stable on a decadal time scale. The frequency and magnitude of recruitment pulses and high rate of adult survival provide considerable inertia, enabling persistence of these populations in the face of sporadic climatic extremes.

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Adult Survival and Imperfect Assessment of Parentage: Effects on Male Parenting Decisions

The American Naturalist ◽

10.2307/2463745 ◽

1999 ◽

Vol 154 (1) ◽

pp. 99

Author(s):

Mauck ◽

Marschall ◽

Parker

Keyword(s):

Adult Survival

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Diversity, Composition and Functional Inference of Gut Microbiota in Indian Cabbage white Pieris canidia (Lepidoptera: Pieridae)

Life ◽

10.3390/life10110254 ◽

2020 ◽

Vol 10 (11) ◽

pp. 254

Author(s):

Ying Wang ◽

Jianqing Zhu ◽

Jie Fang ◽

Li Shen ◽

Shuojia Ma ◽

...

Keyword(s):

Gut Microbiota ◽

16S Rrna Gene Sequencing ◽

Adult Survival ◽

Rrna Gene ◽

Life Stages ◽

Microbial Composition ◽

Significant Difference ◽

Functional Inference ◽

Rrna Gene Sequencing ◽

Insect Fitness

We characterized the gut microbial composition and relative abundance of gut bacteria in the larvae and adults of Pieris canidia by 16S rRNA gene sequencing. The gut microbiota structure was similar across the life stages and sexes. The comparative functional analysis on P. canidia bacterial communities with PICRUSt showed the enrichment of several pathways including those for energy metabolism, immune system, digestive system, xenobiotics biodegradation, transport, cell growth and death. The parameters often used as a proxy of insect fitness (development time, pupation rate, emergence rate, adult survival rate and weight of 5th instars larvae) showed a significant difference between treatment group and untreated group and point to potential fitness advantages with the gut microbiomes in P. canidia. These data provide an overall view of the bacterial community across the life stages and sexes in P. canidia.

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Non-native poeciliids in hot water: the role of thermal springs in facilitating invasion of tropical species

Hydrobiologia ◽

10.1007/s10750-021-04669-9 ◽

2021 ◽

Author(s):

Quenton M. Tuckett ◽

Katelyn M. Lawson ◽

Taylor N. Lipscomb ◽

Jeffrey E. Hill ◽

Wesley M. Daniel ◽

...

Keyword(s):

Hot Water ◽

Thermal Springs ◽

Tropical Species

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A novel non-trichome based whitefly resistance QTL in Solanum galapagense

Euphytica ◽

10.1007/s10681-021-02770-7 ◽

2021 ◽

Vol 217 (3) ◽

Author(s):

Joris Santegoets ◽

Marcella Bovio ◽

Wendy van’t Westende ◽

Roeland E. Voorrips ◽

Ben Vosman

Keyword(s):

Frankliniella Occidentalis ◽

Recombinant Inbred Lines ◽

Glandular Trichomes ◽

Glandular Trichome ◽

Trialeurodes Vaporariorum ◽

Inbred Lines ◽

Adult Survival ◽

Greenhouse Whitefly ◽

Major Threat ◽

Type Iv

AbstractThe greenhouse whitefly Trialeurodes vaporariorum is a major threat in tomato cultivation. In greenhouse grown tomatoes non-trichome based whitefly resistance may be better suited than glandular trichome based resistance as glandular trichomes may interfere with biocontrol, which is widely used. Analysis of a collection of recombinant inbred lines derived from a cross between Solanum lycopersicum and Solanum galapagense showed resistance to the whitefly T. vaporariorum on plants without glandular trichomes type IV. The resistance affected whitefly adult survival (AS), but not oviposition rate. This indicates that S. galapagense, in addition to trichome based resistance, also carries non-trichome based resistance components. The effectiveness of the non-trichome based resistance appeared to depend on the season in which the plants were grown. The resistance also had a small but significant effect on the whitefly Bemisia tabaci, but not on the thrips Frankliniella occidentalis. A segregating F2 population was created to map the non-trichome based resistance. Two Quantitative trait loci (QTLs) for reduced AS of T. vaporariorum were mapped on chromosomes 12 and 7 (explaining 13.9% and 6.0% of the variance respectively). The QTL on chromosome 12 was validated in F3 lines.

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