scholarly journals It’s time to mate: population-level plasticity of wild boar reproductive timing and synchrony in a changing environment

2021 ◽  
Author(s):  
Rudy Brogi ◽  
Enrico Merli ◽  
Stefano Grignolio ◽  
Roberta Chirichella ◽  
Elisa Bottero ◽  
...  
Keyword(s):  
Wild Boar ◽  
Breeding Season ◽  
Environmental Changes ◽  
Reproductive Traits ◽  
Population Level ◽  
Reproductive Phenology ◽  
Reproductive Timing ◽  
Season Length ◽  
Reproductive Patterns ◽  
Breeding Seasons

Abstract On a population-level, individual plasticity in reproductive phenology can provoke either anticipations or delays in the average reproductive timing in response to environmental changes. However, a rigid reliance on photoperiodism can constraint such plastic responses in populations inhabiting temperate latitudes. The regulation of breeding season length may represent a further tool for populations facing changing environments. Nonetheless, this skill was reported only for equatorial, non-photoperiodic populations. Our goal was to evaluate whether species living in temperate regions and relying on photoperiodism to trigger their reproduction may also be able to regulate breeding season length. During 10 years, we collected 2,500 female reproductive traits of a mammal model species (wild boar Sus scrofa) and applied a novel analytical approach to reproductive patterns in order to observe population-level variations of reproductive timing and synchrony under different weather and resources availability conditions. Under favorable conditions, breeding seasons were anticipated and population synchrony increased (i.e., shorter breeding seasons). Conversely, poor conditions induced delayed and less synchronous (i.e., longer) breeding seasons. The potential to regulate breeding season length depending on environmental conditions may entail a high resilience of the population reproductive patterns against environmental changes, as highlighted by the fact that almost all mature females were reproductive every year.

scholarly journals Breeding season length predicts duet coordination and consistency in Neotropical wrens (Troglodytidae)

2020 ◽  
Vol 287 (1941) ◽  
pp. 20202482
Author(s):  
Emily L. Keenan ◽  
Karan J. Odom ◽  
Marcelo Araya-Salas ◽  
Kyle G. Horton ◽  
Matthew Strimas-Mackey ◽  
...  
Keyword(s):  
Clutch Size ◽  
Breeding Season ◽  
Vegetation Density ◽  
Season Length ◽  
Evolutionary Patterns ◽  
Breeding Behaviour ◽  
Breeding Seasons ◽  
Vocal Duets

Many animals produce coordinated signals, but few are more striking than the elaborate male–female vocal duets produced by some tropical songbirds. Yet, little is known about the factors driving the extreme levels of vocal coordination between mated pairs in these taxa. We examined evolutionary patterns of duet coordination and their potential evolutionary drivers in Neotropical wrens (Troglodytidae), a songbird family well known for highly coordinated duets. Across 23 wren species, we show that the degree of coordination and precision with which pairs combine their songs into duets varies by species. This includes some species that alternate their song phrases with exceptional coordination to produce rapidly alternating duets that are highly consistent across renditions. These highly coordinated, consistent duets evolved independently in multiple wren species. Duet coordination and consistency are greatest in species with especially long breeding seasons, but neither duet coordination nor consistency are correlated with clutch size, conspecific abundance or vegetation density. These results suggest that tightly coordinated duets play an important role in mediating breeding behaviour, possibly by signalling commitment or coalition of the pair to mates and other conspecifics.

scholarly journals Density-mediated carry-over effects explain variation in breeding output across time in a seasonal population

2013 ◽  
Vol 9 (5) ◽  
pp. 20130582 ◽  
Author(s):  
Gustavo S. Betini ◽  
Cortland K. Griswold ◽  
D. Ryan Norris
Keyword(s):  
Breeding Season ◽  
Population Level ◽  
Vital Rates ◽  
Previous Season ◽  
Per Capita ◽  
Carry Over ◽  
Individual Success ◽  
Breeding Seasons ◽  
Number Of Individuals ◽  
Seasonal Population

In seasonal environments, where density dependence can operate throughout the annual cycle, vital rates are typically considered to be a function of the number of individuals at the beginning of each season. However, variation in density in the previous season could also cause surviving individuals to be in poor physiological condition, which could carry over to influence individual success in the following season . We examine this hypothesis using replicated populations of Drosophila melanogaster , the common fruitfly, over 23 non-overlapping generations with distinct breeding and non-breeding seasons. We found that the density at the beginning of the non-breeding season negatively affected the fresh weight of individuals that survived the non-breeding season and resulted in a 25% decrease in per capita breeding output among those that survived to the next season to breed. At the population level, per capita breeding output was best explained by a model that incorporated density at the beginning of the previous non-breeding season (carry-over effect, COE) and density at the beginning of the breeding season. Our results support the idea that density-mediated COEs are critical for understanding population dynamics in seasonal environments.

scholarly journals Evidence for use of both capital and income breeding strategies in the mangrove tree crab, Aratus pisonii

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Jade Carver ◽  
Morgan Meidell ◽  
Zachary J. Cannizzo ◽  
Blaine D. Griffen
Keyword(s):  
Breeding Season ◽  
Breeding Strategy ◽  
Reproductive Period ◽  
Breeding Strategies ◽  
Mangrove Tree ◽  
Income Breeding ◽  
Aratus Pisonii ◽  
Breeding Seasons ◽  
And Storage ◽  
Capital And Income Breeding

AbstractTwo common strategies organisms use to finance reproduction are capital breeding (using energy stored prior to reproduction) and income breeding (using energy gathered during the reproductive period). Understanding which of these two strategies a species uses can help in predicting its population dynamics and how it will respond to environmental change. Brachyuran crabs have historically been considered capital breeders as a group, but recent evidence has challenged this assumption. Here, we focus on the mangrove tree crab, Aratus pisonii, and examine its breeding strategy on the Atlantic Florida coast. We collected crabs during and after their breeding season (March–October) and dissected them to discern how energy was stored and utilized for reproduction. We found patterns of reproduction and energy storage that are consistent with both the use of stored energy (capital) and energy acquired (income) during the breeding season. We also found that energy acquisition and storage patterns that supported reproduction were influenced by unequal tidal patterns associated with the syzygy tide inequality cycle. Contrary to previous assumptions for crabs, we suggest that species of crab that produce multiple clutches of eggs during long breeding seasons (many tropical and subtropical species) may commonly use income breeding strategies.

scholarly journals Increased summer food supply decreases non-breeding movement in black-legged kittiwakes

2020 ◽  
Vol 16 (1) ◽  
pp. 20190725 ◽  
Author(s):  
Shannon Whelan ◽  
Scott A. Hatch ◽  
David B. Irons ◽  
Alyson McKnight ◽  
Kyle H. Elliott
Keyword(s):  
Breeding Season ◽  
Food Supply ◽  
Light Level ◽  
Food Supplementation ◽  
Reproductive Phenology ◽  
Rissa Tridactyla ◽  
Breeding Behaviour ◽  
Unlimited Supply ◽  
Migration Phenology ◽  
Carry Over

Individual condition at one stage of the annual cycle is expected to influence behaviour during subsequent stages, yet experimental evidence of food-mediated carry-over effects is scarce. We used a food supplementation experiment to test the effects of food supply during the breeding season on migration phenology and non-breeding behaviour. We provided an unlimited supply of fish to black-legged kittiwakes ( Rissa tridactyla ) during their breeding season on Middleton Island, Alaska, monitored reproductive phenology and breeding success, and used light-level geolocation to observe non-breeding behaviour. Among successful breeders, fed kittiwakes departed the colony earlier than unfed controls. Fed kittiwakes travelled less than controls during the breeding season, contracting their non-breeding range. Our results demonstrate that food supply during the breeding season affects non-breeding phenology, movement and distribution, providing a potential behavioural mechanism underlying observed survival costs of reproduction.

The ecology of the deer mouse Peromyscus maniculatus in a coastal coniferous forest. II. Reproduction

1974 ◽  
Vol 52 (1) ◽  
pp. 119-131 ◽  
Author(s):  
R. M. F. S. Sadleir
Keyword(s):  
Deer Mouse ◽  
Coniferous Forest ◽  
Deer Mice ◽  
Reproductive Phenology ◽  
Corpora Lutea ◽  
Temperature Changes ◽  
Four Seasons ◽  
Different Types ◽  
Breeding Condition ◽  
Breeding Seasons

The duration and intensity of reproduction in deer mice was followed for four seasons by live and dead trapping. Three populations living in different types of forest habitat had synchronous breeding seasons, although there were major differences between years in the time of onset and cessation of breeding and in the proportion of females in breeding condition. No consistent relationships were found between either density changes or the incidence of parasitism and reproductive phenology. In the absence of overt food fluctuations there was a relationship between unseasonable temperature changes and breeding. Sudden increases in temperature may have stimulated the onset of breeding but its cessation before the autumn equinox was always associated with a considerable decrease in temperature if this occurred after April. In 57 pregnancies the corpora lutea count was 4.75 ± 1.12 and embryo count was 4.52 ± 1.16. [Formula: see text].

scholarly journals Density and Flock Size of the Raven (Corvus corax) In the Orawa - Nowy Targ Basin During Non-Breeding Season

Ring ◽  
2006 ◽  
Vol 28 (2) ◽  
pp. 119-125
Author(s):  
Michał Ciach ◽  
Dominik Wikar ◽  
Małgorzata Bylicka
Keyword(s):  
Breeding Season ◽  
Early Spring ◽  
Food Resources ◽  
High Density ◽  
Line Transect ◽  
Flock Size ◽  
Early Winter ◽  
Corvus Corax ◽  
Line Transect Method ◽  
Breeding Seasons

Density and Flock Size of the Raven (Corvus corax) In the Orawa - Nowy Targ Basin During Non-Breeding Season During the 2002/2003-2004/2005 non-breeding seasons the density of the Raven in the open habitats of the Orawa - Nowy Targ Basin was studied by line transect method. The results were analysed in four periods (autumn, early winter, winter and early spring). The median density of Ravens did not differ significantly between individual periods and was respectively: 3.5, 3.8, 4.8 and 3.8 indiv. / 10 km. Number of birds during particular controls varied from 1.0 to 24.8 indiv. / 10 km. However, while excluding flocks, the median density of single individuals and pairs of the Raven was considerably lower and in subsequent periods reached respectively: 2.2, 2.4, 2.2 and 1.7 indiv. / 10 km. Flock size did not differ significantly between individual periods. Single individuals and, less often, groups of two birds were recorded mostly. Small (3-5 indiv.) and medium (6-15 indiv.) flocks were recorded rarely and large flocks (16 indiv. and above) - only exceptionally. The high density and strong fluctuations of abundance of Ravens were determined by flocks presence, which was probably linked to irregular occurrence of food resources.

scholarly journals Reef development and Sea level changes drive Acanthaster Population Expansion in the Indo-Pacific region

2020 ◽  
Author(s):  
P.C. Pretorius ◽  
T.B. Hoareau
Keyword(s):  
Population Size ◽  
Sea Level ◽  
Environmental Changes ◽  
Sequence Data ◽  
Demographic History ◽  
Population Expansion ◽  
Population Level ◽  
Sea Level Changes ◽  
Reef Development ◽  
Curve Fitting Method

AbstractMolecular clock calibration is central in population genetics as it provides an accurate inference of demographic history, whereby helping with the identification of driving factors of population changes in an ecosystem. This is particularly important for coral reef species that are seriously threatened globally and in need of conservation. Biogeographic events and fossils are the main source of calibration, but these are known to overestimate timing and parameters at population level, which leads to a disconnection between environmental changes and inferred reconstructions. Here, we propose the Last Glacial Maximum (LGM) calibration that is based on the assumptions that reef species went through a bottleneck during the LGM, which was followed by an early yet marginal increase in population size. We validated the LGM calibration using simulations and genetic inferences based on Extended Bayesian Skyline Plots. Applying it to mitochondrial sequence data of crown-of-thorns starfish Acanthaster spp., we obtained mutation rates that were higher than phylogenetically based calibrations and varied among populations. The timing of the greatest increase in population size differed slightly among populations, but all started between 10 and 20 kya. Using a curve-fitting method, we showed that Acanthaster populations were more influenced by sea-level changes in the Indian Ocean and by reef development in the Pacific Ocean. Our results illustrate that the LGM calibration is robust and can probably provide accurate demographic inferences in many reef species. Application of this calibration has the potential to help identify population drivers that are central for the conservation and management of these threatened ecosystems.

scholarly journals Large-scale comparison of biomass and reproductive phenology among native and non-native populations of the seagrass Zostera japonica

2021 ◽  
Vol 675 ◽  
pp. 1-21
Author(s):  
MA Ito ◽  
HJ Lin ◽  
MI O’Connor ◽  
M Nakaoka
Keyword(s):  
North America ◽  
North American ◽  
Large Scale ◽  
Reproductive Phenology ◽  
Reproductive Timing ◽  
Zostera Japonica ◽  
Tropical Asia ◽  
Maximum Biomass ◽  
Peak Biomass ◽  
Native Populations

Large-scale analysis along latitude or temperature gradients can be an effective method for exploring the potential roles of light and temperature in controlling seagrass phenology. In this study, we investigated effects of latitude and temperature on seagrass biomass and reproductive seasonality. Zostera japonica is an intertidal seagrass with a wide latitudinal distribution expanding from tropical to temperate zones in its native range in Asia, with an additional non-native distribution in North America. We collated available data on phenological traits (timings of peak biomass or reproduction, durations of biomass growth and reproductive season, and maximum biomass or reproductive ratio) from publications and our own observations. Traits were compared among geographic groups: Asia-tropical, Asia-temperate, and North America-temperate. We further examined relationships between traits and latitude and temperature for 3 population groups: Asian, North American, and all populations. Our analysis revealed significant variation among geographic groups in maximum biomass, peak reproductive timing, and maximum reproductive ratio, but not in other traits. Maximum biomass and peak reproductive timing for Asian and all populations were significantly correlated with latitude and temperature. Maximum biomass was highest at mid-latitudes or intermediate temperatures and decreased toward distribution range limits, and peak reproductive timing occurred later in the year at higher latitudes or cooler sites. North American populations showed shorter growth durations and greater reproductive ratios at higher latitude. Different responses observed for North American populations may reflect effects of introduction. Our study demonstrates potential variation among geographic regions and between native and non-native populations.

scholarly journals Lovesick: Immunological Costs of Mating of Male Sagebrush Crickets

2008 ◽  
Vol 31 ◽  
pp. 109-114
Author(s):  
Joseph Lehman ◽  
Carie Weddle ◽  
Jeannine St. John ◽  
Angela Kerr ◽  
Susan Gershman ◽  
...  
Keyword(s):  
Immune Response ◽  
Cell Walls ◽  
Reproductive Traits ◽  
Sexual Signals ◽  
Mating Status ◽  
Encapsulation Rate ◽  
Investment In Reproduction ◽  
Virgin Male ◽  
Cyphoderris Strepitans ◽  
Breeding Seasons

A growing body of evidence suggests that resources invested in sexual signals and other reproductive traits often come at the expense of the ability to mount an immune response. Male sagebrush crickets, Cyphoderris strepitans, offer an unusual nuptial food gift to females during mating: females chew on the tips of males' fleshy hind wings and ingest hemolymph seeping from the wounds they inflict. Previous research has shown that once a male has mated, his probability of obtaining an additional copulation is reduced relative to that of a virgin male seeking his first mating. One hypothesis to account for this effect is that wing wounding triggers an energetically costly immune response, such that non­ virgin males are unable to sustain the costly acoustical signaling needed to attract additional females. To test this hypothesis, we injected virgin males with lipopolysaccharides (LPS), a non-living component of bacterial cell walls that leads to upregulation of the insect immune system. Males were released in the field and recaptured over the course of the breeding season to monitor their mating success. Over two breeding seasons, LPS-injected males took significantly longer to secure matings than sham-injected virgin males. An encapsulation rate assay showed no difference in the encapsulation response of males of different mating status, but virgin males had significantly higher levels of phenoloxidase than non-virgin males. These results suggest that males trade off investment in reproduction and investment in immunity.

Phenotypic plasticity of the montane vole (Microtus montanus) in unpredictable environments

1992 ◽  
Vol 70 (11) ◽  
pp. 2121-2124 ◽  
Author(s):  
Norman C. Negus ◽  
Patricia J. Berger ◽  
Aelita J. Pinter
Keyword(s):  
Phenotypic Plasticity ◽  
Breeding Season ◽  
Growth Rates ◽  
Adaptive Strategy ◽  
Severe Drought ◽  
Microtus Montanus ◽  
Age Cohort ◽  
Montane Meadow ◽  
Study Sites ◽  
Breeding Seasons

From 1987 to 1989, the cohort dynamics of Microtus montanus populations were studied at two montane meadow sites approximately 160 km apart, in northwestern Wyoming. The 1987 and 1988 breeding seasons differed markedly from each other. In 1987, melt off occurred in April, and the first cohort was born in May (cohort 1). The entire breeding season was favorable owing to frequent rainfall throughout the summer. Cohort 1 animals grew rapidly and females began breeding at 4–5 weeks of age. Likewise, cohort 2 (June) animals exhibited rapid growth and females were breeding at 7–8 weeks of age. Cohort 3 (July and August) animals grew more slowly and most entered the winter as prepubertal animals of subadult size. At the end of the summer, cohort 3 animals represented >70% of the voles recruited during the breeding season. In 1988, following melt off in late April, precipitation was below normal and the situation intensified to severe drought through the summer. The growth rates of cohort 1 and 2 animals were significantly lower than 1987 growth rates, and very few females attained sexual maturity. At the end of the summer, cohort 3 animals represented <25% of the total recruitment at both study sites. Such apparent phenotypic plasticity of growth and maturation appears to be an evolved adaptive strategy that is responsive to several environmental cues. Both study sites, although widely separated, exhibited virtually identical patterns throughout the study.

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