Breeding performance of Common Terns (Sterna hirundo) does not decline among older age classes

The Auk ◽  
2020 ◽  
Vol 137 (3) ◽  
Author(s):  
Ian C T Nisbet ◽  
David Iles ◽  
Andrew Kaneb ◽  
Carolyn S Mostello ◽  
Stéphanie Jenouvrier
Keyword(s):  
Reproductive Performance ◽  
Reproductive Effort ◽  
Older Age ◽  
Laying Date ◽  
Sterna Hirundo ◽  
Age Classes ◽  
Reproductive Senescence ◽  
Fledging Success ◽  
Common Terns ◽  
Age Related

Abstract Declines in reproductive performance among older age classes have been reported in many bird and mammal species, and are commonly presented as demonstrating reproductive senescence. However, no declines in performance could be demonstrated in studies of several bird species. We measured reproductive performance in Common Terns (Sterna hirundo) of known age (2–28 yr) during a 19-yr period at a site in Buzzards Bay, Massachusetts, USA. We measured 6 components of reproductive performance and used generalized additive mixed models (GAMMs) in a Bayesian framework to analyze dependence of each measure on parental age, while controlling for variations among years and indices of individual quality. Four measures of performance improved (earlier laying date, higher values of clutch size, fledging success, and productivity) with age, most rapidly between ages 2 and 10 yr; egg mass and hatching success varied only slightly with age. No measure of performance showed reversals among the older age classes; fledging success and productivity continued to increase through at least age 22 yr. These findings are consistent with results from an earlier study of the same species. Continued increase in reproductive performance through the oldest age classes is not incompatible with “reproductive senescence” (decline in physiological or other functions required for successful reproduction) if either reproductive effort or efficiency continue to increase. Studies within our population have yielded no evidence for age-related increase in reproductive effort, but 3 studies have suggested that older Common Terns can raise chicks more successfully than younger birds without increasing reproductive effort, probably by more efficient foraging and chick provisioning. Our findings suggest that Common Terns offset reproductive senescence by continuing to improve efficiency through at least age 22 yr. Age-related changes in efficiency should be investigated in other species with similar life-history traits.

The impact of dietary protein:carbohydrate balance on lifespan and reproduction in Protaetia brevitarsis (Coleoptera: Scarabaeidae: Cetoniinae)

2021 ◽  
pp. 1-8
Author(s):  
S.-H. Kim ◽  
H. Park ◽  
W. Kim ◽  
J.-H. Song ◽  
S.J. Roh ◽  
...  
Keyword(s):  
Reproductive Performance ◽  
Egg Production ◽  
Detailed Knowledge ◽  
Reproductive Senescence ◽  
Egg Hatchability ◽  
Edible Insect ◽  
Age Related ◽  
Medicinal Value ◽  
Egg Production Rate ◽  
The Impact

The establishment of efficient and sustainable production of industrially important insects necessitates the detailed knowledge of the optimal mixture of macronutrients required for maximising their performance and fitness. The white spotted flower chafer, Protaetia brevitarsis (Coleoptera: Scarabaeidae: Cetoniinae), is one of the most important edible insects in East Asia with high nutritional and medicinal value. Here, we report how the ratio of protein to digestible carbohydrate (P:C) in the diet influenced lifespan and reproductive performance in the adults of P. brevitarsis. Throughout their lifespan, beetles were fed ad libitum one of five diets with differing P:C ratio (0:1, 3:7, 1:1, 7:3, 1:0). Both lifespan and the number of eggs produced over the lifetime were maximised at the P:C ratio of 3:7 and declined as the ratio deviated away from this optimal P:C composition. Beetles fed a diet containing only protein (P:C 1:0) not only had the shortest lifespan but also exhibited substantially reduced lifetime egg production compared to those fed the other diets. However, the effects of dietary P:C ratio on daily egg production rate and egg hatchability were marginal. The number of eggs produced at each age stage peaked at the age of week 2 and then gradually declined with increasing age, showing the sign of reproductive senescence. Age-specific egg production was higher in beetles confined to three intermediate P:C ratios (3:7, 1:1, 7:3) than those confined to two extreme P:C ratios (0:1, 1:0) throughout their lifespan. The speed of age-related decrease in reproductive performance was the slowest at P:C 3:7. Our data have implications for optimising the production of this edible insect with emerging economic importance.

Chick provisioning by common terns in the southern Gulf of Maine, U.S.A.

2000 ◽  
Vol 78 (1) ◽  
pp. 158-160 ◽  
Author(s):  
C Reed Rossell, Jr. ◽  
Christine D Hamilton ◽  
Louise M Weber ◽  
Stephen W Kress
Keyword(s):  
Gulf Of Maine ◽  
Weather Conditions ◽  
Sterna Hirundo ◽  
Age Classes ◽  
Hatching Order ◽  
Common Terns ◽  
Older Siblings

We examined chick provisioning by common terns (Sterna hirundo) in relation to hatching order, chick stage, and weather on Stratton Island, Maine, U.S.A., during the summer of 1997. Provisioning rates, recorded at 10 nests during 30-min observation sessions (n = 256), were calculated for first-, second-, and third-hatched chicks in three age-classes (1-5, 6-10, and 11-15 days). Mean provisioning rates did not differ significantly with hatching order of chicks. However, a trend toward differential provisioning was evident during the earliest chick stage. Mean provisioning rates increased significantly from age-classs 1 to 2 and decreased significantly from age-classes 2 to 3. Weather had no significant effects on provisioning rates, owing to the unusually mild and consistent conditions. These results indicate that during the earliest chick stage, older siblings in a brood may have an advantage in obtaining food, even when weather conditions are highly favorable for provisioning chicks.

Within-season and age-related patterns of reproductive performance in female tree swallows (Tachycineta bicolor)

1988 ◽  
Vol 66 (4) ◽  
pp. 827-834 ◽  
Author(s):  
Bridget J. Stutchbury ◽  
Raleigh J. Robertson
Keyword(s):  
Clutch Size ◽  
Breeding Season ◽  
Reproductive Performance ◽  
Tachycineta Bicolor ◽  
Foraging Efficiency ◽  
Tree Swallows ◽  
Age Classes ◽  
Age Related ◽  
Female Tree ◽  
Second Year

In many species of birds, clutch size decreases as the season progresses, but this is confounded by the fact that young birds not only often have smaller clutches but also breed later than older females. We examined the effect of time of season on clutch size, hatching success, and fledging success of female tree swallows (Tachycineta bicolor) in their second year (SY) and after their second year (ASY), and compared their reproductive performance while controlling for time of season. For both SY and ASY females, clutch size decreased significantly with later first egg dates, which caused number hatched and number fledged per brood to also decline as the season progressed. However, neither the proportion of eggs hatched nor the proportion of young fledged was correlated with first egg date. The within-season decline in clutch size was not due simply to replacement clutches or female age, and we argue that it is also not due to a decrease in food abundance over the breeding season. Age-related differences in reproductive success depended on the time of season. Early in the breeding season, ASY females were superior to SY females in every measure of reproductive performance; however, there were no significant differences between age-classes late in the season. ASY females were more successful than SY females in raising clutches of five or six eggs, which were most common early in the season, but there was no difference between age-classes in raising clutches of four eggs. We suggest that an age-related difference in foraging efficiency and within-season changes in the cost of competition could explain this pattern.

Individual changes underlie age-specific pattern of laying date and egg-size in female common terns Sterna hirundo

2004 ◽  
Vol 145 (2) ◽  
pp. 129-136 ◽  
Author(s):  
Jacob Gonz�lez-Sol�s ◽  
Peter H. Becker ◽  
Lluis Jover ◽  
Xavier Ruiz
Keyword(s):  
Egg Size ◽  
Specific Pattern ◽  
Laying Date ◽  
Sterna Hirundo ◽  
Common Terns

The Biological Clock and Sleep in the Elderly

2006 ◽  
Vol 19 (1) ◽  
pp. 45-51 ◽  
Author(s):  
Myriam Juda ◽  
Mirjam Münch ◽  
Anna Wirz-Justice ◽  
Martha Merrow ◽  
Till Roenneberg
Keyword(s):  
Circadian Rhythms ◽  
Biological Clock ◽  
The Elderly ◽  
Early Morning ◽  
Behavioral Changes ◽  
Older Age ◽  
Age Related ◽  
Theoretical Considerations ◽  
Sleep Difficulties ◽  
Circadian Biology

Abstract: Among many other changes, older age is characterized by advanced sleep-wake cycles, changes in the amplitude of various circadian rhythms, as well as reduced entrainment to zeitgebers. These features reveal themselves through early morning awakenings, sleep difficulties at night, and a re-emergence of daytime napping. This review summarizes the observations concerning the biological clock and sleep in the elderly and discusses the documented and theoretical considerations behind these age-related behavioral changes, especially with respect to circadian biology.

scholarly journals Age-Related Frailty: A Clinical Model for Geroscience?

2020 ◽  
Vol 24 (10) ◽  
pp. 1140-1143 ◽  
Author(s):  
Catherine Takeda ◽  
D. Angioni ◽  
E. Setphan ◽  
T. Macaron ◽  
P. De Souto Barreto ◽  
...  
Keyword(s):  
Heart Failure ◽  
Congestive Heart Failure ◽  
Medical History ◽  
Older Age ◽  
The Other ◽  
Everyday Practice ◽  
Clinical Model ◽  
Main Contributor ◽  
Age Related ◽  
History Of

AbstractIn their everyday practice, geriatricians are confronted with the fact that older age and multimorbidity are associated to frailty. Indeed, if we take the example of a very old person with no diseases that progressively becomes frail with no other explanation, there is a natural temptation to link frailty to aging. On the other hand, when an old person with a medical history of diabetes, arthritis and congestive heart failure becomes frail there appears an obvious relationship between frailty and comorbidity. The unsolved question is: Considering that frailty is multifactorial and in the majority of cases comorbidity and aging are acting synergistically, can we disentangle the main contributor to the origin of frailty: disease or aging? We believe that it is important to be able to differentiate age-related frailty from frailty related to comorbidity. In fact, with the emergence of geroscience, the physiopathology, diagnosis, prognosis and treatment will probably have to be different in the future.

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